Diabetes mellitus type 1 (also known as type 1 diabetes, or T1DM; formerly insulin dependent

diabetes or juvenile diabetes) is a form of diabetes mellitus that results

fromautoimmune destruction of insulin-producing beta cells of the pancreas.[2] The subsequent lack

of insulin leads to increased blood and urine glucose. The classical symptoms are polyuria(frequent

urination), polydipsia (increased thirst), polyphagia (increased hunger), and weight loss.[3]

Incidence varies from 8 to 17 per 100,000 in Northern Europe and the U.S. with a high of about 35

per 100,000 in Scandinavia to a low of 1 per 100,000 in Japan and China.[4]

Untreated, type 1 diabetes is ultimately fatal, but the disease can be controlled with supplemental

insulin. Insulin is most commonly administered by injection at periodic intervals several times per

day, though other options, such as insulin pumps, exist. Transplantation, both of the entire

pancreas and pancreatic islet cells, is a possible cure in some cases.

Type 1 diabetes can be distinguished from type 2 by autoantibody testing - glutamic acid

decarboxylase autoantibodies (GADA), islet cell autoantibodies (ICA), insulinoma-associated (IA-2)

autoantibodies, and zinc transporter autoantibodies (ZnT8) are present in individuals with type 1

diabetes, but not type 2. The C-peptide assay, which measures endogenous insulin production, can

also be used.

Treatment must be continued indefinitely and does not usually impair normal daily activities. Patients

are usually trained to manage their disease independently, but for some individuals this can be a

challenge. Complications may arise from both low blood sugar and high blood sugar, both due to the

non-physiological manner in which insulin is replaced. Low blood sugar may lead to seizures or

episodes of unconsciousness, and requires emergency treatment. High blood sugar may lead to

increased fatigue and can cause long-term damage to organs

Signs and symptoms[edit]

Overview of the most significant symptoms of diabetes

The classical symptoms of type 1 diabetes include: polyuria (frequent

urination), polydipsia (increased thirst), Xerostomia (dry mouth), polyphagia (increased hunger),

fatigue, and weight loss.[3]Type 1 diabetics are often first diagnosed when they present with diabetic

ketoacidosis. These symptoms could be xeroderma (dry skin), rapid deep breathing,

drowsiness, abdominal pain, and vomiting.[5]

Cause[edit]

Diabetes type 1 is induced by one or more of the following: genetic susceptibility, a diabetogenic

trigger and/or exposure to a driving antigen.[6]

Boston Children’s Hospital research also identified ATP/P2X7R protein as a possible trigger.

Genetics[edit]

Type 1 diabetes is a polygenic disease, meaning many different genes contribute to its onset.

Depending on locus or combination of loci, it can be dominant, recessive, or somewhere in between.

The strongest gene, IDDM1, is located in the MHC Class II region on chromosome 6, at staining

region 6p21. Certain variants of this gene increase the risk for

decreasedhistocompatibility characteristic of type 1. Such variants include DRB1 0401, DRB1 0402,

DRB1 0405, DQA 0301, DQB1 0302 and DQB1 0201, which are common in North Americans of

European ancestry and in Europeans.[7] Some variants also appear to be protective.[7]

The risk of a child developing type 1 diabetes is about 10% if the father has it, about 10% if a sibling

has it, about 4% if the mother has type 1 diabetes and was aged 25 or younger when the child was

born, and about 1% if the mother was over 25 years old when the child was born.[8]

Environmental[edit]

Environmental factors can influence expression of type 1. For identical twins, when one twin had

type 1 diabetes, the other twin only had it 30%–50% of the time. Despite having exactly the same

genome, one twin had the disease, where the other did not; this suggests environmental factors, in

addition to genetic factors, can influence disease prevalence.[9] Other indications of environmental

influence include the presence of a 10-fold difference in occurrence among Caucasians living in

different areas of Europe, and a tendency to acquire the incidence of the disease of the destination

country for people who migrate.[6]

Virus[edit]

One theory, discussed by DeLisa Fairweather and Noel R. Rose, among others,[10] proposes that

type 1 diabetes is a virus-triggered autoimmune response in which the immune system attacks virus-

infected cells along with the beta cells in the pancreas. The Coxsackie virus family or rubella is

implicated, although the evidence is inconclusive. In type 1, pancreatic beta cells in the islets of

Langerhans are destroyed, decreasing endogenous insulin production. This distinguishes type 1's

origin from type 2. The type of diabetes a patient has is determined only by the cause—

fundamentally by whether the patient is insulin resistant (type 2) or insulin deficient without insulin

resistance (type 1).

This vulnerability is not shared by everyone, for not everyone infected by the suspected virus

develops type 1 diabetes. This has suggested presence of a genetic vulnerability[11] and there is

indeed an observed inherited tendency to develop type 1. It has been traced to

particular HLA genotypes, though the connection between them and the triggering of an autoimmune

reaction is still poorly understood.

Diet[edit]

Some researchers believe the autoimmune response is influenced by antibodies against cow's

milk proteins.[12]

Vitamin D in doses of 2000 IU per day given during the first year of a child's life has been connected

in one study in northern Finland (where intrinsic production of Vitamin D is low due to low natural

light levels) with an 80% reduction in the risk of getting type 1 diabetes later in life.[citation needed]

Having a short breastfeeding period as well as short attendance at day care are associated with an

elevated risk of type 1 diabetes in Czech children.[13]

Chemicals and drugs[edit]

Some chemicals and drugs preferentially destroy pancreatic cells. Pyrinuron (Vacor, N-3-

pyridylmethyl-N'-p-nitrophenyl urea), a rodenticide introduced in the United States in 1976,

selectively destroys pancreatic beta cells, resulting in type 1 diabetes after accidental or intentional

ingestion. Vacor was withdrawn from the U.S. market in 1979, but is still used in some countries.

Zanosar is the trade name for streptozotocin, an antibiotic and antineoplastic agent used in

chemotherapy for pancreatic cancer; it also kills beta cells, resulting in loss of insulin production.

Other pancreatic problems, including trauma, pancreatitis or tumors (either malignant or benign), can

also lead to loss of insulin production.

Pathophysiology[edit]

The pathophysiology in diabetes type 1 is a destruction of beta cells in the pancreas, regardless of

which risk factors or causative entities have been present.

Individual risk factors can have separate pathophysiological processes to, in turn, cause this beta

cell destruction. Still, a process that appears to be common to most risk factors is an autoimmune

response towards beta cells, involving an expansion of autoreactive CD4+ T helper cells and CD8+

T cells, autoantibody-producing B cells and activation of the innate immune system.[7][14]

Diagnosis[edit]

See also: Glycated hemoglobin and Glucose tolerance test

Diabetes diagnostic criteria[15][16]  edit

Condition 2 hour glucose Fasting glucose HbA1c

mmol/l(mg/dl) mmol/l(mg/dl) %

Normal <7.8 (<140) <6.1 (<110) <6.0

Impaired fasting glycaemia <7.8 (<140) ≥ 6.1(≥110) & <7.0(<126) 6.0–6.4

Impaired glucose

tolerance≥7.8 (≥140) <7.0 (<126) 6.0–6.4

Diabetes mellitus ≥11.1 (≥200) ≥7.0 (≥126) ≥6.5

Diabetes mellitus is characterized by recurrent or persistent hyperglycemia, and is diagnosed by

demonstrating any one of the following:[17]

Fasting plasma glucose level at or above 7.0 mmol/L (126 mg/dL).

Plasma glucose  at or above 11.1 mmol/L (200 mg/dL) two hours after a 75 g oral glucose load

as in a glucose tolerance test.

Symptoms of hyperglycemia and casual plasma glucose at or above 11.1 mmol/L (200 mg/dL).

Glycated hemoglobin  (hemoglobin A1C) at or above 6.5. (This criterion was recommended by

the American Diabetes Association in 2010, although it has yet to be adopted by the WHO.)[18]

About a quarter of people with new type 1 diabetes have developed some degree of

diabetic ketoacidosis (a type of metabolic acidosis which is caused by high concentrations of ketone

bodies, formed by the breakdown of fatty acids and the deamination of amino acids) by the time the

diabetes is recognized. The diagnosis of other types of diabetes is usually made in other ways.

These include ordinary health screening, detection of hyperglycemia during other medical

investigations, and secondary symptoms such as vision changes or unexplainable fatigue. Diabetes

is often detected when a person suffers a problem that may be caused by diabetes, such as a heart

attack, stroke, neuropathy, poor wound healing or a foot ulcer, certain eye problems, certain fungal

infections, or delivering a baby withmacrosomia or hypoglycemia.

A positive result, in the absence of unequivocal hyperglycemia, should be confirmed by a repeat of

any of the above-listed methods on a different day. Most physicians prefer to measure a fasting

glucose level because of the ease of measurement and the considerable time commitment of formal

glucose tolerance testing, which takes two hours to complete and offers no prognostic advantage

over the fasting test.[19] According to the current definition, two fasting glucose measurements above

126 mg/dL (7.0 mmol/L) is considered diagnostic for diabetes mellitus.

Patients with fasting glucose levels from 100 to 125 mg/dL (5.6 to 6.9 mmol/L) are considered to

have impaired fasting glucose. Patients with plasma glucose at or above 140 mg/dL (7.8 mmol/L),

but not over 200 mg/dL (11.1 mmol/L), two hours after a 75 g oral glucose load are considered to

have impaired glucose tolerance. Of these two pre-diabetic states, the latter in particular is a major

risk factor for progression to full-blown diabetes mellitus and cardiovascular disease.[20]

Autoantibodies[edit]

The appearance of diabetes-related autoantibodies has been shown to be able to predict the

appearance of diabetes type 1 before any hyperglycemia arises, the main ones being islet cell

autoantibodies, insulin autoantibodies, autoantibodies targeting the 65-kDa isoform of glutamic acid

decarboxylase (GAD), autoantibodies targeting the phosphatase-related IA-2 molecule, and zinc

transporter autoantibodies (ZnT8).[6] By definition, the diagnosis of diabetes type 1 can be made first

at the appearance of clinical symptoms and/or signs, but the emergence of autoantibodies may itself

be termed "latent autoimmune diabetes". Not everyone with autoantibodies progresses to diabetes

type 1, but the risk increases with the number of antibody types, with three to four antibody types

giving a risk of progressing to diabetes type 1 of 60%–100%.[6] The time interval from emergence of

autoantibodies to frank diabetes type 1 can be a few months in infants and young children, but in

some people it may take years – in some cases more than 10 years.[6] Islet cell autoantibodies are

detected by conventional immunofluorescence, while the rest are measured with

specific radiobinding assays.[6]

Prevention[edit]

Type 1 diabetes is not currently preventable.[21] Some researchers believe it might be prevented at

the latent autoimmune stage, before it starts destroying beta cells.[7]

Immunosuppressive drugs[edit]

Cyclosporine A, an immunosuppressive agent, has apparently halted destruction of beta cells (on

the basis of reduced insulin usage), but its nephrotoxicity and other side effects make it highly

inappropriate for long-term use.[7]

Anti-CD3 antibodies, including teplizumab and otelixizumab, had suggested evidence of preserving

insulin production (as evidenced by sustained C-peptide production) in newly diagnosed type 1

diabetes patients.[7] A probable mechanism of this effect was believed to be preservation

of regulatory T cells that suppress activation of the immune system and thereby maintain immune

system homeostasis and tolerance to self-antigens.[7] The duration of the effect is still unknown,

however.[7] In 2011, Phase III studies with otelixizumab and teplizumab both failed to show clinical

efficacy, potentially due to an insufficient dosing schedule.[22][23]

An anti-CD20 antibody, rituximab, inhibits B cells and has been shown to provoke C-

peptide responses three months after diagnosis of type 1 diabetes, but long-term effects of this have

not been reported.[7]

Diet[edit]

Some research has suggested breastfeeding decreases the risk in later life;[24][25] various other

nutritional risk factors are being studied, but no firm evidence has been found.[26] Giving children

2000 IU of Vitamin D during their first year of life is associated with reduced risk of type 1 diabetes,

though the causal relationship is obscure.[27]

Children with antibodies to beta cell proteins (i.e. at early stages of an immune reaction to them) but

no overt diabetes, and treated with vitamin B3 the niacinamide version, had less than half the

diabetes onset incidence in a seven-year time span than did the general population, and an even

lower incidence relative to those with antibodies as above, but who received no niacinamide.[28]

Type 1 diabetes is also referred to as "sugar diabetes" due to the fact that a diet consisting of large

amounts of sugar can be fatal. Diets consisting of large quantities of fat (i.e. butter and oil) also put

the patient at a higher risk of cardiovascular disease.

Management[edit]

Further information: Diabetes management

Insulin therapy[edit]

Main article: Insulin therapy

Type 1 is treated with insulin replacement therapy—either via subcutaneous injection or insulin

pump, along with attention to dietary management, typically including carbohydrate tracking, and

careful monitoring of blood glucose levels using glucose meters. Today, the most common insulins

are biosynthetic products produced using genetic recombination techniques; formerly, cattle or pig

insulins were used, and even sometimes insulin from fish.[29] Major global suppliers include Eli Lilly

and Company, Novo Nordisk, and Sanofi-Aventis. A more recent trend, from several suppliers,

is insulin analogs which are slightly modified insulins with different onset or duration of action times.

Untreated type 1 diabetes commonly leads to coma, often from diabetic ketoacidosis, which is fatal if

untreated. Ketoacidosis causes cerebral edema (accumulation of liquid in the brain). This

complication is very life-threatening; it makes ketoacidosis the most common cause of death in

pediatric diabetes.[30]

Continuous glucose monitors can alert patients to the presence of dangerously high or low blood

sugar levels, but technical issues have limited the effect these devices have had on clinical

practice[citation needed].

Treatment of diabetes focuses on lowering blood sugar or glucose (BG) to the near normal range,

approximately 80–140 mg/dl (4.4–7.8 mmol/L).[31] The ultimate goal of normalizing BG is to avoid

long-term complications that affect the nervous system (e.g. peripheral neuropathy leading to pain

and/or loss of feeling in the extremities), and the cardiovascular system (e.g. heart attacks, vision

loss). People with type 1 diabetes always need to use insulin, but treatment can lead to low BG

(hypoglycemia), i.e. BG less than 70 mg/dl (3.9 mmol/l). Hypoglycemia is a very common occurrence

in people with diabetes, usually the result of a mismatch in the balance among insulin, food and

physical activity, although the nonphysiological method of delivery also plays a role.

Pancreas transplantation[edit]

Main article: Pancreas transplantation

In more extreme cases, a pancreas transplant can restore proper glucose regulation. However, the

surgery and accompanying immunosuppression required is considered by many physicians to be

more dangerous than continued insulin replacement therapy, so is generally only used with or some

time after a kidney transplant. One reason for this is that introducing a new kidney requires

taking immunosuppressive drugs such as cyclosporine. Nevertheless this allows the introduction of a

new, functioning pancreas to a patient with diabetes without any additional immunosuppressive

therapy. However, pancreas transplants alone can be wise in patients with extremely labile type 1

diabetes mellitus.[32]

Islet cell transplantation[edit]

Main article: Islet cell transplantation

Experimental replacement of beta cells (by transplant or from stem cells) is being investigated in

several research programs. Islet cell transplantation is less invasive than a pancreas transplant,

which is currently the most commonly used approach in humans.

In one variant of this procedure, islet cells are injected into the patient's liver, where they take up

residence and begin to produce insulin. The liver is expected to be the most reasonable choice

because it is more accessible than the pancreas, and islet cells seem to produce insulin well in that

environment. The patient's body, however, will treat the new cells just as it would any other

introduction of foreign tissue, unless a method is developed to produce them from the patient's own

stem cells or an identical twin is available who can donate stem cells. The immune system will attack

the cells as it would a bacterial infection or a skin graft. Thus, patients now also need to undergo

treatment involvingimmunosuppressants, which reduce immune system activity.

Recent studies have shown islet cell transplants have progressed to the point where 58% of the

patients in one study were insulin-independent one year after transplantation.[33] Scientists in New

Zealand with Living Cell Technologies are currently in human trials with Diabecell, placing pig islets

within a protective capsule derived of seaweed which enables insulin to flow out and nutrients to flow

in, while protecting the islets from immune system attack via white blood cells.

Stem Cell Educator Therapy[edit]

Stem Cell Educator Therapy induces immune balance by using cord blood-derived multipotent stem

cells[34] with embryonic and hematopoietic characteristics. A closed-loop system that circulates a

patient's blood through a blood cell separator, briefly co-cultures the patient's lymphocytes with

adherent cord blood stem cells in vitro, and returns the educated lymphocytes (but not the cord

blood stem cells) to the patient's circulation.[35] Through the Stem Cell Education process the

patient's lymphocytes are modified by the Autoimmune Regulator AIRE that activates

certain genes due to contact with the cord blood stem cells.

The clinical trial (NCT01350219) reveals that a single treatment with the Stem Cell Educator

provides lasting reversal of autoimmunity that allows improvement of metabolic control[36] in subjects

with long-standing type 1 diabetes. The on-going phase II clinical study about Stem Cell Educator

Therapy has proved 100% effectiveness in type 1 diabetics, even in patients who lost the ability to

produce their own insulin (C-peptide < 0,01 µg/l before treatment).

After treatment, the increased expression of co-stimulating molecules (specifically, CD28 and ICOS),

increases in the number of CD4+CD25+Foxp3+ Tregs, and restoration

of Th1/Th2/Th3 cytokine balance indicate this therapy reversesautoimmunity, induces tolerance and

promotes regeneration of islet beta cells[37] without showing any adverse effects so far.

Successful immune modulation by cord blood stem cells and the resulting clinical improvement in

patient status may have important implications for other autoimmune diseases but does not raise

any safety or ethical issues.

Psychological effects[edit]

Depression[edit]

Depression and depressive symptoms are generally more common in people living with type 1

diabetes. One review article suggested that the prevalence rate of depression is more than three

times higher in diabetics than non-diabetics; an average prevalence of 12% was found (range of

5.8–43.4% in studies reviewed)[38] Women with type 1 diabetes are more likely to be depressed than

men with type 1 diabetes,[38] and an increased incidence of depression has also been associated

with youth with type 1 diabetes.[39] According to the Canadian Diabetes Association, 15% of people

living with diabetes have major depression.[40] Psychological distress is also reported in the parents

of youth with type 1 diabetes.[41] Recent evidence has suggested that reduced pre-frontal cortical

thickness is associated with depression in people with type 1 diabetes. These neurological changes

may be caused by long-term reduced glycemic control and may increase risk of depression.[42]

Eating disorders[edit]

Recent research has found that eating disorders are more common in females with type 1

diabetes[43] (prevalence = 10.15%) than in females without it (prevalence = 4.5%), as were sub-

threshold eating disorders (13.8% vs. 7.6%)[44]Some participants (11.0%) in the same study reported

manipulating insulin dosages to promote weight loss. Higher blood-sugar levels are associated with

polyuria and reduced appetite, which can result in weight loss. Similarly, mean hemoglobin A1c

levels were higher in participant with a DSM-IV disorder (9.4%) than those without (8.6%). This

behavior was reported by 42% of participant who had a DSM-IV disorder.

The disorder of omission of insulin for weight control has been named diabulimia, a portmanteau of

diabetes and bulimia, although it is not currently recognized as a formal diagnosis in the medical

community.

Social cognition and self-care[edit]

Results from recent research suggest that people with type 1 diabetes may neglect precise self-care

due to social fear related to fear of hypoglycemia.[45] Type 1 diabetics may also neglect physical

activity due to reduced perceived position effects as well as increased perceived negative aspects of

that activity.[46]

Complications[edit]

Further information: Complications of diabetes mellitus

Complications of poorly managed type 1 diabetes mellitus may include cardiovascular

disease, diabetic neuropathy, and diabetic retinopathy, among others. However, cardiovascular

disease[47] as well as neuropathy[48] may have an autoimmune basis, as well.

Driving[edit]

Studies conducted in the United States[49] and Europe[50] showed that drivers with type 1 diabetes

had twice as many collisions as their nondiabetic spouses, demonstrating the increased risk

of driving collisions in the type 1 diabetes population. Diabetes can compromise driving safety in

several ways. First, long-term complications of diabetes can interfere with the safe operation of a

vehicle. For example, diabetic retinopathy (loss of peripheral vision or visual acuity), or peripheral

neuropathy (loss of feeling in the feet) can impair a driver's ability to read street signs, control the

speed of the vehicle, apply appropriate pressure to the brakes, etc.

Second, hypoglycemia can affect a person's thinking processes, coordination, and state

of consciousness.[51][52] This disruption in brain functioning, neuroglycopenia, can impair driving

ability.[51][53] A study involving people with type 1 diabetes found that individuals reporting two or more

hypoglycemia-related driving mishaps differ physiologically and behaviorally from their counterparts

who report no such mishaps.[54] For example, during hypoglycemia, drivers who had two or more

mishaps reported fewer warning symptoms, their driving was more impaired, and their body released

less epinephrine (a hormone that helps raise BG). Additionally, individuals with a history of

hypoglycemia-related driving mishaps appear to use sugar at a faster rate[55] and are relatively

slower at processing information.[56] These findings indicate that although anyone with type 1

diabetes may be at some risk of experiencing disruptive hypoglycemia while driving, there is a

subgroup of type 1 drivers who are more vulnerable to such events.

Given the above research findings, drivers with type 1 diabetes and a history of driving mishaps are

recommended to never drive when their BG is less than 80 mg/dl. Instead, these drivers are advised

to treat hypoglycemia and delay driving until their BG is above 90 mg/dl.[54] Such drivers should also

learn as much as possible about what causes their hypoglycemia, and use this information to avoid

future hypoglycemia while driving.

Studies funded by the National Institutes of Health (NIH) have demonstrated that face-to-face

training programs designed to help individuals with type 1 diabetes better anticipate, detect, and

prevent extreme BG can reduce the occurrence of future hypoglycemia-related driving mishaps.[57][58]

[59] An internet-version of this training has also been shown to have significant beneficial results.[60] Additional NIH funded research to develop internet interventions specifically to help improve

driving safety in drivers with type 1 diabetes is currently underway.[61]

Epidemiology[edit]

Type 1 diabetes causes an estimated 5–10% of all diabetes cases[62] or 11–22 million worldwide.[21] In 2006 it affected 440,000 children under 14 years of age and was the primary cause of diabetes

in those less than 10 years of age.[63] The incidence of type 1 diabetes has been increasing by about

3% per year.[63]

Rates vary widely by country. In Finland, the incidence is a high of 35 per 100,000 per year, in Japan

and China a low of 1 to 3 per 100,000 per year, and in Northern Europe and the U.S., an

intermediate of 8 to 17 per 100,000 per year.[4][64]

Type 1 diabetes was previously known as juvenile diabetes to distinguish it from type 2 diabetes,

which generally has a later onset; however, the majority of new-onset type 1 diabetes is seen in

adults. Studies using antibody testing (glutamic acid decarboxylase antibodies, islet cell antibodies,

and insulinoma-associated autoantibodies) to distinguish between type 1 and type 2 diabetes

demonstrate that most new-onset type 1 diabetes is seen in adults. Adult-onset type 1 autoimmune

diabetes is two to three times more common than classic childhood-onset autoimmune diabetes.[65]

Economics[edit]

In the US in 2008, about one million people were diagnosed with type 1 diabetes. The disease was

estimated to cause $10.5 billion in annual medical costs ($875 per month per diabetic) and an

additional $4.4 billion in indirect costs ($366 per month per person with diabetes).[66]

Research[edit]

Funding for research into type 1 diabetes originates from government, industry (e.g., pharmaceutical

companies), and charitable organizations. Government funding in the United States is distributed via

the National Institute of Health, and in the UK via the National Institute for Health Research or

the Medical Research Council. The Juvenile Diabetes Research Foundation, originally founded by

parents of children with type 1 diabetes, is the world's largest provider of charity based funding for

type 1 diabetes research. Other charities include the American Diabetes Association, Diabetes UK,

Diabetes Research and Wellness Foundation,[67] Diabetes Australia, the Canadian Diabetes

Association.

Types of research[edit]

A significant amount of research is being undertaken in type 1 diabetes, and these will be outlined in

the links that fund the research mentioned above. Clinical trials in type 1 diabetes that are currently

ongoing can also be found online.[68][69]

Generally the research can be divided into the following categories:

Before people get type 1 diabetes[edit]

Research here relates to prevention of type 1 diabetes in those deemed at risk.

After people get type 1 diabetes[edit]

Research here relates to therapies aimed at cure (islet transplant, pancreas transplant and stem

cells), the artificial pancreas, prevention of diabetic complications, new insulins and other drugs for

treating type 1 diabetes.

At the time people are diagnosed type 1 diabetes[edit]

People generally have some residual insulin producing beta cells present at the time they are

diagnosed with type 1 diabetes. The exact number of cells is difficult to know but current estimates

suggest that this can be anywhere between 10–25%. These cells are not sufficient to cope with the

body's insulin requirements (which is why the blood sugar levels are high), and the person will need

immediate insulin treatment. However preserving these cells has been shown to have long lasting

health benefits including reducing the rates of hypoglycaemia and risks of complications.[70] There is

therefore a significant amount of research now being undertaken in patients newly diagnosed with

type 1 diabetes to see if residual beta cells can be preserved. This research includes:

using drugs to suppress the autoimmune response against the remaining beta cells. Many of

these trials are coordinated via TRIALNET[71] – an international group of researchers with an

interest in preventing type 1 diabetes. These drugs can work either through suppressing the

whole immune response (e.g. anti CD3, anti CD20, CTLA4-Ig, anti-IL1 beta), or whether more

specific 'antigen specific' drugs can be found that just suppress the immune response against

the islet. The latter will clearly be better because it has less risk of side effects, but is harder to

achieve.

adopting a healthier lifestyle to preserve beta cells. Research has already shown that exercise is

very effective at preserving beta cells in people with type 2 diabetes. Therefore research is now

being conducted to see if exercise can have the same benefit in type 1 diabetes.[72]

Specific Areas of Research[edit]

GAD65 vaccine[edit]

Injections with a vaccine containing GAD65, an autoantigen involved in type 1 diabetes, has in

clinical trials delayed the destruction of beta cells when treated within six months of diagnosis.[7] Patients treated with the substance showed higher levels of regulatory cytokines, thought to

protect the beta cells.[73] Phase III trials are under way in the USA[74] and in Europe.[75][76][77] Two

prevention studies, where the vaccine is given to persons who have not yet developed diabetes are

underway.[78][79][80]

T helper cell shift[edit]

If a biochemical mechanism can be found to prevent the immune system from attacking beta cells, it

may be administered to prevent commencement of diabetes type 1. Several groups are trying to

achieve this by causing the activation state of the immune system to change from type 1 T helper

cell (Th1) state ("attack" by killer T Cells) to Th2 state (development of new antibodies). This Th1-

Th2 shift occurs via a change in the type of cytokine signaling molecules being released by T-cells.

Instead of proinflammatory cytokines, the T-cells begin to release cytokines that inhibit inflammation.[81] This phenomenon is commonly known as acquired immune tolerance.

Labile diabetes[edit]

Insulin-dependent diabetes characterized by dramatic and recurrent swings in glucose levels, often

occurring for no apparent reason, is sometimes known as brittle diabetes, unstable diabetes or labile

diabetes, although some experts say the "brittle diabetes" concept "has no biologic basis and should

not be used".[82] The results of such swings can be irregular and unpredictable hyperglycemias,

frequently involving ketosis, and sometimes serious hypoglycemias. Brittle diabetes occurs no more

frequently than in 1% to 2% of diabetics.[83] An insulin pump may be recommended for brittle

diabetes to reduce the number of hypoglycemic episodes and better control the morning rise of

blood sugar due to the dawn phenomenon.[84] In a small study, 10 of 20 brittle diabetic patients aged

18–23 years who could be traced had died within 22 years, and the remainder, though suffering high

rates of complications, were no longer brittle.[85] These results were similar to those of an earlier

study by the same authors which found a 19% mortality in 26 patients after 10.5 years.[86]

Because labile diabetes is defined as "episodes of hypoglycemia or hyperglycemia that, whatever

their cause, constantly disrupt a patient's life", it can have many causes, some of which include:[87]

errors in diabetes management, which can include too much insulin being given.

interactions with other medical conditions.

psychological problems.

biological factors that interfere with how insulin is processed within the body.

One of these biological factors is the production of insulin autoantibodies. High antibody titers can

cause episodes of hyperglycemia by neutralizing the insulin, cause clinical insulin

resistance requiring doses of over 200 IU/day. However, antibodies may also fail to buffer the

release of the injected insulin into the bloodstream after subcutaneous injection, resulting in

episodes of hypoglycemia. In some cases, changing the type of insulin administered can resolve this

problem.[87] There have been a number of reports that insulin autoantibodies can act as a "sink" for

insulin and affect the time to peak, half-life, distribution space, and metabolic clearance, though in

most patients these effects are small.[88]

Type 1 diabetes, once known as juvenile diabetes or insulin-dependent diabetes, is a chronic

condition in which the pancreas produces little or no insulin, a hormone needed to allow sugar

(glucose) to enter cells to produce energy. The far more common type 2 diabetes occurs when the

body becomes resistant to the effects of insulin or doesn't make enough insulin.

Various factors may contribute to type 1 diabetes, including genetics and exposure to certain

viruses. Although type 1 diabetes typically appears during childhood or adolescence, it also can

develop in adults.

Despite active research, type 1 diabetes has no cure, although it can be managed. With proper

treatment, people who have type 1 diabetes can expect to live longer, healthier lives than they did in

the past.

SymptomsBy Mayo Clinic staff

Controlling Your Diabetes

Type 1 diabetes signs and symptoms can come on quickly and may include:

Increased thirst and frequent urination

Extreme hunger

Weight loss

Fatigue

Blurred vision

When to see a doctor 

Consult your doctor if you notice any type 1 diabetes signs and symptoms.

CausesBy Mayo Clinic staff

The exact cause of type 1 diabetes is unknown. In most people with type 1 diabetes, the body's own

immune system — which normally fights harmful bacteria and viruses — mistakenly destroys the

insulin-producing (islet) cells in the pancreas. Genetics may play a role in this process, and exposure

to certain viruses may trigger the disease.

The role of insulin 

Once the islet cells are destroyed, you'll produce little or no insulin. Insulin is a hormone that comes

from the pancreas, a gland situated behind and below the stomach.

The pancreas secretes insulin into the bloodstream.

The insulin circulates, enabling sugar to enter your cells.

Insulin lowers the amount of sugar in your bloodstream.

As your blood sugar level drops, so does the secretion of insulin from your pancreas.

The role of glucose 

Glucose — a sugar — is a main source of energy for the cells that make up muscles and other

tissues.

Glucose comes from two major sources: food and your liver.

Sugar is absorbed into the bloodstream, where it enters cells with the help of insulin.

Your liver stores glucose as glycogen.

When your insulin levels are low, such as when you haven't eaten in a while, the liver converts

stored glycogen into glucose to keep your glucose level within a normal range.

In type 1 diabetes, there's no insulin to let glucose into the cells, so sugar builds up in your

bloodstream, where it can cause life-threatening complications.

The cause of type 1 diabetes is different from the cause of the more familiar type 2 diabetes. In type

2 diabetes, the islet cells are still functioning, but the body becomes resistant to insulin, or the

pancreas doesn't produce enough insulin or both.

Risk factorsBy Mayo Clinic staff

There aren't many known risk factors for type 1 diabetes, though researchers continue to find new

possibilities. Some known risk factors include:

A family history. Anyone with a parent or sibling with type 1 diabetes has a slightly increased risk of

developing the condition.

Genetics. The presence of certain genes indicates an increased risk of developing type 1 diabetes.

In some cases — usually through a clinical trial — genetic testing can be done to determine if

someone who has a family history of type 1 diabetes is at increased risk of developing the condition.

Geography. The incidence of type 1 diabetes tends to increase as you travel away from the

equator. People living in Finland and Sardinia have the highest incidence of type 1 diabetes — about

two to three times higher than rates in the United States and 400 times that of people living in

Venezuela.

Possible risk factors for type 1 diabetes include:

Viral exposure. Exposure to Epstein-Barr virus, coxsackievirus, mumps virus or cytomegalovirus

may trigger the autoimmune destruction of the islet cells, or the virus may directly infect the islet

cells.

Early vitamin D. Research suggests that vitamin D may be protective against type 1 diabetes.

However, early drinking of cow's milk — a common source of vitamin D — has been linked to an

increased risk of type 1 diabetes.

Other dietary factors. Omega-3 fatty acids may offer some protection against type 1 diabetes.

Drinking water that contains nitrates may increase the risk. Consuming dairy products, particularly

cow's milk, may increase infants' risk of the disease. Additionally, the timing of the introduction of

cereal into a baby's diet may affect risk. One clinical trial found that between ages 3 and 7 months

appears to be the optimal time for introducing cereal.

Some other possible risk factors include:

Having a mother younger than age 25 when she gave birth to you.

Having a mother who had preeclampsia during pregnancy.

Being born with jaundice.

Having a respiratory infection just after birth.

ComplicationsBy Mayo Clinic staff

Controlling Your Diabetes

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Type 1 diabetes can affect major organs in your body, including heart, blood vessels, nerves, eyes

and kidneys. Keeping your blood sugar level close to normal most of the time can dramatically

reduce the risk of many complications.

Long-term complications of type 1 diabetes develop gradually, over years. The earlier you develop

diabetes — and the less controlled your blood sugar — the higher the risk of complications.

Eventually, diabetes complications may be disabling or even life-threatening.

Heart and blood vessel disease. Diabetes dramatically increases your risk of various

cardiovascular problems, including coronary artery disease with chest pain (angina), heart attack,

stroke, narrowing of the arteries (atherosclerosis) and high blood pressure.

Nerve damage (neuropathy). Excess sugar can injure the walls of the tiny blood vessels

(capillaries) that nourish your nerves, especially in the legs. This can cause tingling, numbness,

burning or pain that usually begins at the tips of the toes or fingers and gradually spreads upward.

Poorly controlled blood sugar could cause you to eventually lose all sense of feeling in the affected

limbs. Damage to the nerves that affect the gastrointestinal tract can cause problems with nausea,

vomiting, diarrhea or constipation. For men, erectile dysfunction may be an issue.

Kidney damage (nephropathy). The kidneys contain millions of tiny blood vessel clusters that filter

waste from your blood. Diabetes can damage this delicate filtering system. Severe damage can lead

to kidney failure or irreversible end-stage kidney disease, which requires dialysis or a kidney

transplant.

Eye damage. Diabetes can damage the blood vessels of the retina (diabetic retinopathy), potentially

leading to blindness. Diabetes also increases the risk of other serious vision conditions, such as

cataracts and glaucoma.

Foot damage. Nerve damage in the feet or poor blood flow to the feet increases the risk of various

foot complications. Left untreated, cuts and blisters can become serious infections. Severe damage

might require toe, foot or even leg amputation.

Skin and mouth conditions. Diabetes may leave you more susceptible to skin problems, including

bacterial and fungal infections. Gum infections also may be a concern, especially if you have a

history of poor dental hygiene.

Osteoporosis. Diabetes may lead to lower than normal bone mineral density, increasing your risk of

osteoporosis.

Pregnancy complications. High blood sugar levels can be dangerous for both the mother and the

baby. The risk of miscarriage, stillbirth and birth defects are increased when diabetes isn't well

controlled. For the mother, diabetes increases the risk of diabetic ketoacidosis, diabetic eye

problems (retinopathy), pregnancy-induced high blood pressure and preeclampsia.

Hearing problems. Hearing impairments occur more often in people with diabetes.

ests and diagnosisBy Mayo Clinic staff

Controlling Your Diabetes

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In June 2009, an international committee of experts from the American Diabetes Association, the

European Association for the Study of Diabetes and the International Diabetes Federation

recommended that type 1 diabetes testing include the:

Glycated hemoglobin (A1C) test. This blood test indicates your average blood sugar level for the

past two to three months. It works by measuring the percentage of blood sugar attached to

hemoglobin, the oxygen-carrying protein in red blood cells. The higher your blood sugar levels, the

more hemoglobin you'll have with sugar attached. An A1C level of 6.5 percent or higher on two

separate tests indicates you have diabetes.

If the A1C test isn't available, or if you have certain conditions that can make the A1C test inaccurate

— such as if you're pregnant or have an uncommon form of hemoglobin (known as a hemoglobin

variant) — your doctor may use the following tests to diagnose diabetes:

Random blood sugar test. A blood sample will be taken at a random time. Blood sugar values are

expressed in milligrams per deciliter (mg/dL) or millimoles per liter (mmol/L). Regardless of when

you last ate, a random blood sugar level of 200 mg/dL (11.1 mmol/L) or higher suggests diabetes,

especially when coupled with any of the signs and symptoms of diabetes, such as frequent urination

and extreme thirst.

Fasting blood sugar test. A blood sample will be taken after an overnight fast. A fasting blood

sugar level less than 100 mg/dL (5.6 mmol/L) is normal. A fasting blood sugar level from 100 to 125

mg/dL (5.6 to 6.9 mmol/L) is considered prediabetes. If it's 126 mg/dL (7 mmol/L) or higher on two

separate tests, you have diabetes.

If you're diagnosed with diabetes, your doctor will also run blood tests to check for autoantibodies

that are common in type 1 diabetes. These tests help your doctor distinguish between type 1 and

type 2 diabetes. The presence of ketones — byproducts from the breakdown of fat — in your urine

also suggests type 1 diabetes, rather than type 2.

After the diagnosis 

Once you've been diagnosed with type 1 diabetes, you'll regularly visit your doctor to ensure good

diabetes management. During these visits, the doctor will check your A1C levels. Your target A1C

goal may vary depending on your age and various other factors, but the American Diabetes

Association generally recommends that A1C levels be below 7 percent, which translates to an

estimated average glucose of 154 mg/dL (8.5 mmol/L).

Compared with repeated daily blood sugar tests, A1C testing better indicates how well your diabetes

treatment plan is working. An elevated A1C level may signal the need for a change in your insulin

regimen, meal plan or both.

In addition to the A1C test, the doctor will also take blood and urine samples periodically to check

your cholesterol levels, thyroid function, liver function and kidney function. The doctor will also

examine you to assess your blood pressure, and he or she will check the sites where you test your

blood sugar and deliver insulin.

Treatments and drugsBy Mayo Clinic staff

Insulin pump

Controlling Your Diabetes

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Treatment for type 1 diabetes is a lifelong commitment to:

Taking insulin

Exercising regularly and maintaining a healthy weight

Eating healthy foods

Monitoring blood sugar

The goal is to keep your blood sugar level as close to normal as possible to delay or prevent

complications. Although there are exceptions, generally, the goal is to keep your daytime blood

sugar levels before meals between 80 and 120 mg/dL (4.4 to 6.7 mmol/L) and your bedtime

numbers between 100 and 140 mg/dL (5.6 to 7.8 mmol/L).

If managing your diabetes seems overwhelming, take it one day at a time. And remember that you're

not alone. You'll work closely with your diabetes treatment team to keep your blood sugar level as

close to normal as possible.

Insulin and other medications 

Anyone who has type 1 diabetes needs insulin therapy. After the diagnosis, there may be a

"honeymoon" period, during which blood sugar is controlled with little or no insulin. However, this

phase doesn't last.

Types of insulin are many and include:

Rapid-acting insulin

Long-acting insulin

Intermediate options

Examples are regular insulin (Humulin 70-30, Novolin 70/30, others), insulin isophane (Humulin N,

Novolin N), insulin lispro (Humalog) and insulin aspart (Novolog). Long-acting insulins include

glargine (Lantus) and detemir (Levemir).

Depending on your needs, your doctor may prescribe a mixture of insulin types to use throughout

the day and night.

Insulin can be administered using:

A fine needle and syringe

An insulin pen — a device that looks like an ink pen, except the cartridge is filled with insulin

An insulin pump — a device about the size of a cellphone worn on the outside of your body. A tube

connects a reservoir of insulin to a catheter that's inserted under the skin of your abdomen. There's

also a wireless pump option that's available in most areas. You wear a reservoir of insulin on your

body that has a tiny catheter that's inserted under your skin. The insulin pod can be worn on your

abdomen, lower back, or on a leg or an arm. The programming is done with a wireless device that

communicates with the pod.

Pumps are programmed to dispense specific amounts of rapid-acting insulin automatically. This

steady dose of insulin is known as your basal rate, and it replaces whatever long-acting insulin you

were using. When you eat, you program the pump with the amount of carbohydrates you're eating

and your current blood sugar, and it will give you what's called a "bolus" dose of insulin to cover your

meal and to correct your blood sugar if it's elevated. Some research has found that in some people

an insulin pump can be more effective at controlling blood sugar levels than injections.

An emerging treatment approach, not yet available, is closed loop insulin delivery, also known as the

artificial pancreas. It links a continuous glucose monitor to an insulin pump. The device automatically

delivers the correct amount of insulin when the monitor indicates the need for it. Testing has shown

encouraging results, but more research is needed.

Insulin can't be taken orally to lower blood sugar because stomach enzymes interfere with insulin's

action.

Oral medications, however, are sometimes prescribed, such as:

High blood pressure medications. Even if you don't have high blood pressure, your doctor may

prescribe medications known as angiotensin-converting enzyme (ACE) inhibitors or angiotensin II

receptor blockers (ARBs), because these medications also can help keep your kidneys healthy. It's

recommended that people with diabetes have blood pressures less than 130/80 millimeters of

mercury (mm Hg).

Aspirin. Your doctor may recommend you take baby or regular aspirin daily to protect your heart.

Cholesterol-lowering drugs. As with high blood pressure drugs, your doctor may not wait until your

cholesterol is elevated before he or she prescribes cholesterol-lowering agents known as statins.

Cholesterol guidelines are more aggressive for people with diabetes because of the elevated risk of

heart disease. The American Diabetes Association recommends that low-density lipoprotein (LDL, or

"bad") cholesterol be below 100 mg/dL (2.6 mmol/L) and that high-density lipoprotein (HDL, or

"good") cholesterol be over 50 mg/dL (1.3 mmol/L). Triglycerides, another type of blood fat, are ideal

when they're less than 150 mg/dL (1.7 mmol/L).

Your doctor might also prescribe pramlintide (Symlin). An injection of this medication before you eat

can slow the movement of food through your stomach to curb the sharp increase in blood sugar that

occurs after meals.

Healthy eating and monitoring carbohydrates 

Contrary to popular perception, there's no such thing as a diabetes diet. You won't be restricted to a

lifetime of boring, bland foods. Instead, you'll need to center your diet on nutritious, low-fat, high-fiber

foods such as:

Fruits

Vegetables

Whole grains

You'll eat fewer animal products and refined carbohydrates, such as white bread and sweets. This is

the best overall eating plan, even for people without diabetes.

You'll need to learn how to assess the carbohydrates in the foods you eat so that you can give

yourself enough insulin to properly metabolize those carbohydrates. A registered dietitian can help

you create a meal plan that fits your health goals, food preferences and lifestyle.

Physical activity 

Everyone needs regular aerobic exercise, and people who have type 1 diabetes are no exception.

Get your doctor's OK to exercise. Then choose activities you enjoy, such as walking, swimming or

biking. Make physical activity part of your daily routine. Aim for at least 30 minutes of aerobic

exercise most days of the week. Flexibility and strength training exercises are important, too. If you

haven't been active for a while, start slowly and build up gradually.

Remember that physical activity lowers blood sugar, often for long after you're done working out. If

you begin a new activity, check your blood sugar level more often than usual until you know how that

activity affects your blood sugar levels. You might need to adjust your meal plan or insulin doses to

compensate for the increased activity. If you use an insulin pump, you can set a temporary basal

rate to keep your blood sugar from dropping. Ask your doctor or diabetes educator to show you how.

Blood sugar monitoring 

Depending on what type of insulin therapy you select or require — twice daily injections, multiple

daily injections or insulin pump — you may need to check and record your blood sugar level at least

four times a day, and possibly more often. Careful monitoring is the only way to make sure that your

blood sugar level remains within your target range. Be sure to wash your hands before checking

your blood sugar levels.

Even if you take insulin and eat on a rigid schedule, the amount of sugar in your blood can change

unpredictably. With help from your diabetes treatment team, you'll learn how your blood sugar level

changes in response to:

Food. What and how much you eat will affect your blood sugar level. Blood sugar is typically highest

one to two hours after a meal.

Physical activity. Physical activity moves sugar from your blood into your cells. The more active

you are, the lower your blood sugar level. To compensate, you might need to lower your insulin dose

before unusual physical activity.

Medication. You need insulin to lower your blood sugar level. But other medications you take may

affect your blood sugar level as well, sometimes requiring changes in your diabetes treatment plan.

Illness. During a cold or other illness, your body may produce hormones that raise your blood sugar

level. This might require changes in your diabetes treatment plan.

Alcohol. Alcohol can cause either high or low blood sugar, depending on how much you drink and if

you eat at the same time. If you choose to drink, do so in moderation, which means no more than

one drink a day for women and two drinks or fewer daily for men.

Stress. The hormones your body may produce in response to prolonged stress may prevent insulin

from working properly.

For women, fluctuations in hormone levels. As your hormone levels fluctuate during your

menstrual cycle, so can your blood sugar level — particularly in the week before your period.

Menopause may trigger fluctuations in your blood sugar level as well.

Continuous glucose monitoring (CGM) is the newest way to monitor blood sugar levels, and may be

most helpful for people who have developed hypoglycemia unawareness. Continuous glucose

monitors attach to the body using a fine needle just under the skin that checks blood glucose level

every few minutes. CGM isn't yet considered as accurate as standard blood sugar monitoring, so it's

not considered a replacement method for keeping track of blood sugar, but an additional measure

for some people.

Situational concerns 

Certain life circumstances call for different considerations.

Driving. Hypoglycemia can occur at any time, even when you're driving. It's a good idea to check

your blood sugar anytime you're getting behind the wheel. If it's below 70 mg/dL (3.9 mmol/L), have

a snack and then retest again in 15 minutes to make sure it's risen to a safe level. Low blood sugar

makes it hard to concentrate or to react as rapidly as you might need to when you're driving.

Working. In the past, people with type 1 diabetes were often refused certain jobs because they had

diabetes. Fortunately, advances in diabetes management and anti-discrimination laws have made

such blanket bans largely a thing of the past. However, type 1 diabetes can pose some challenges in

the workplace. For example, if you work in a job that involves driving or operating heavy machinery,

hypoglycemia could pose a serious risk to you and those around you. You may need to work with

your doctor and your employer to ensure that certain accommodations are made, such as your

having a quick break for blood sugar testing and fast access to food and drink anytime, so you can

properly manage your diabetes and prevent low blood sugar levels. There are federal and state laws

in place that require employers to make reasonable accommodations for people with diabetes.

Being pregnant. Because the risk of pregnancy complications is higher for women with type 1

diabetes, experts recommend that women have a preconception evaluation and that A1C readings

should be less than 7 percent before you attempt to get pregnant. Some drugs, such as high blood

pressure medications and cholesterol-lowering medications, may need to be stopped before

pregnancy. The risk of birth defects is increased for women with type 1 diabetes, particularly when

diabetes is poorly controlled during the first six to eight weeks of pregnancy, so planning your

pregnancy is key. Careful management of your diabetes during pregnancy can decrease your risk of

complications.

Being older. As long as you're still active and have normal cognitive abilities, your diabetes

management goals will likely be the same as they were when you were younger. But, for those who

are frail, sick or have cognitive deficits, tight control of blood sugar may not be practical. If you're

caring for a loved one with type 1 diabetes, ask his or her doctor what the new diabetes goals should

be.

Investigational treatments

Pancreas transplant. With a successful pancreas transplant, you would no longer need insulin. But

pancreas transplants aren't always successful — and the procedure poses serious risks. You would

need a lifetime of potent immune-suppressing drugs to prevent organ rejection. These drugs can

have serious side effects, including a high risk of infection and organ injury. Because the side effects

can be more dangerous than the diabetes itself, pancreas transplants are generally reserved for

those with very difficult-to-control diabetes.

Islet cell transplantation. Researchers are experimenting with islet cell transplantation, which

provides new insulin-producing cells from a donor pancreas. Although this experimental procedure

has met with problems in the past, new techniques and better drugs to prevent islet cell rejection

may improve its future chance for success. However, islet cell transplantation still requires the use of

immune-suppressing medications, and just as it did with its own natural islet cells, the body often

destroys transplanted islet cells, making the time off injected insulin short-lived. Additionally, a

sufficient supply of islet cells isn't available for this treatment to become more widespread.

Stem cell transplant. In a 2007 Brazilian study, a small number of people newly diagnosed with

type 1 diabetes were able to stop using insulin after being treated with stem cells made from their

own blood. Although stem cell transplants — which involve shutting down the immune system and

then building it up again — can be risky, the technique may one day provide an additional treatment

option for type 1 diabetes.

Signs of trouble 

Despite your best efforts, sometimes problems will arise. Certain short-term complications of type 1

diabetes require immediate care. Left untreated, these conditions can cause seizures and loss of

consciousness (coma).

Low blood sugar (hypoglycemia). This occurs when your blood sugar level drops below your

target range. Ask your doctor what's considered a low blood sugar level for you. Blood sugar levels

can drop for many reasons, including skipping a meal, getting more physical activity than normal or

injecting too much insulin.

Learn the symptoms of low blood sugar, and test your blood sugar if you think your blood sugar

levels are dropping. When in doubt, always do a blood sugar test. Early signs and symptoms of low

blood sugar include:

Sweating

Shakiness

Hunger

Weakness

Anxiety

Dizziness or lightheadedness

Pale skin

Rapid or irregular heart rate

Fatigue

Headaches

Blurred vision

Irritability

Later signs and symptoms of low blood sugar, which can sometimes be mistaken for alcohol

intoxication in teens and adults include:

Lethargy

Confusion

Behavior changes, sometimes dramatic

Poor coordination

Convulsions

If you develop hypoglycemia during the night, you might wake with sweat-soaked pajamas or a

headache. Thanks to a natural rebound effect, nighttime hypoglycemia might cause an unusually

high blood sugar reading first thing in the morning.

If you have a low blood sugar reading:

Have some fruit juice, glucose tablets, hard candy, regular (not diet) soda or another source of

sugar.

Retest your blood sugar in about 15 minutes to make sure it's normal.

If it's not normal, have more juice, candy, glucose tablets or other source of sugar, and retest in

another 15 minutes.

Repeat until you get a normal reading.

Eat a mixed food source, such as peanut butter and crackers, to help stabilize your blood sugar.

If a blood glucose meter isn't readily available, treat for low blood sugar anyway if you have

symptoms of hypoglycemia, and then test as soon as possible.

Always carry a source of fast-acting sugar with you. Left untreated, low blood sugar will cause you to

lose consciousness. If this occurs, you may need an emergency injection of glucagon — a hormone

that stimulates the release of sugar into the blood. Be sure you always have a glucagon emergency

kit available — at home, at work, when you're out — and make sure it hasn't expired.

Hypoglycemia unawareness. Some people may lose the ability to sense that their blood sugar

levels are getting low, because they've developed a condition known as hypoglycemia unawareness.

With hypoglycemia unawareness, the body no longer reacts to a low blood sugar with symptoms

such as lightheadedness or headaches. The more you experience low blood sugars, the more likely

you are to develop hypoglycemia unawareness. The good news is that if you can avoid having a

hypoglycemic episode for several weeks, you may start to become more aware of impending lows.

High blood sugar (hyperglycemia). Your blood sugar can rise for many reasons, including eating

too much, eating the wrong types of foods, not taking enough insulin or illness.

Watch for:

Frequent urination

Increased thirst

Blurred vision

Fatigue

Nausea

Irritability

Hunger

Difficulty concentrating

If you suspect hyperglycemia, check your blood sugar. You might need to adjust your meal plan or

medications. If your blood sugar is higher than your target range, you'll likely need to administer a

"correction" using an insulin shot or through an insulin pump. A correction is an additional dose of

insulin that should bring your blood sugar back into the normal range. High blood sugar levels don't

come down as quickly as they go up. Ask your doctor how long to wait until you recheck. If you use

an insulin pump, random high blood sugar readings may mean you need to change the pump site.

If you have two consecutive blood sugar readings above 250 mg/dL (13.9 mmol/L), test for ketones

using a urine test stick. Don't exercise if your blood sugar level is very high or if ketones are present.

If only a trace or small amounts of ketones are present, drink extra fluids to flush out the ketones.

If your blood sugar is persistently above 300 mg/dL (16.7 mmol/L), call your doctor or seek

emergency care.

Increased ketones in your urine (diabetic ketoacidosis). If your cells are starved for energy, your

body may begin to break down fat — producing toxic acids known as ketones.

Signs and symptoms of this serious condition include:

Nausea

Vomiting

Abdominal pain

A sweet, fruity smell on your breath

Weight loss

If you suspect ketoacidosis, check your urine for excess ketones with an over-the-counter ketones

test kit. If you have large amounts of ketones in your urine, call your doctor right away or seek

emergency care. Also, call your doctor if you have vomited more than once and you have ketones in

your urine.

Lifestyle and home remediesBy Mayo Clinic staff

Controlling Your Diabetes

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Type 1 diabetes is a serious disease. Following your diabetes treatment plan takes round-the-clock

commitment, which can be frustrating at times. But realize that your efforts are worthwhile. Careful

management of type 1 diabetes can reduce your risk of serious — even life-threatening —

complications. Consider these tips:

Make a commitment to managing your diabetes. Take your medications as recommended. Learn

all you can about type 1 diabetes. Make healthy eating and physical activity part of your daily

routine. Establish a relationship with a diabetes educator, and ask your diabetes treatment team for

help when you need it.

Identify yourself. Wear a tag or bracelet that says you have diabetes. Keep a glucagon kit nearby

in case of a low blood sugar emergency — and make sure your friends and loved ones know how to

use it.

Schedule a yearly physical exam and regular eye exams. Your regular diabetes checkups aren't

meant to replace yearly physicals or routine eye exams. During the physical, your doctor will look for

any diabetes-related complications, as well as screen for other medical problems. Your eye care

specialist will check for signs of retinal damage, cataracts and glaucoma.

Keep your immunizations up to date. High blood sugar can weaken your immune system. Get a

flu shot every year, and get a tetanus booster shot every 10 years. Your doctor will likely recommend

the pneumonia vaccine, as well. The Centers for Disease Control and Prevention (CDC) also

currently recommends hepatitis B vaccination if you haven't previously been vaccinated against

hepatitis B and you're an adult ages 19 to 59 with type 1 or type 2 diabetes. The most recent CDC

guidelines advise vaccination as soon as possible after diagnosis with type 1 or type 2 diabetes. If

you're age 60 or older and have diabetes and haven't previously received the vaccine, talk to your

doctor about whether it's right for you.

Take care of your teeth. Diabetes may leave you prone to gum infections. Brush your teeth at least

twice a day, floss your teeth once a day and schedule dental exams at least twice a year. Consult

your dentist right away if your gums bleed or look red or swollen.

Pay attention to your feet. Wash your feet daily in lukewarm water. Dry them gently, especially

between the toes, and moisturize with lotion. Check your feet every day for blisters, cuts, sores,

redness or swelling. Consult your doctor if you have a sore or other foot problem that doesn't heal.

Keep your blood pressure and cholesterol under control. Eating healthy foods and exercising

regularly can go a long way toward controlling high blood pressure and cholesterol. Medication may

be needed, too.

If you smoke or use other forms of tobacco, ask your doctor to help you quit. Smoking

increases your risk of various diabetes complications, including heart attack, stroke, nerve damage

and kidney disease. In fact, smokers who have diabetes are three times more likely to die of

cardiovascular disease than are nonsmokers who have diabetes, according to the American

Diabetes Association. Talk to your doctor about ways to stop smoking or to stop using other types of

tobacco.

If you drink alcohol, do so responsibly. Alcohol can cause either high or low blood sugar,

depending on how much you drink and if you eat at the same time. If you choose to drink, do so only

in moderation and always with a meal.

Maintain a healthy weight. Good diabetes control is easier when you're at a healthy weight. If you

need to lose weight, ask your doctor about healthy ways to reduce. Some people manipulate their

insulin use to induce diabetic ketoacidosis to lose weight — a condition known as diabulimia. This is

an unhealthy way to lose weight and extremely dangerous.

Take stress seriously. If you're stressed, it's easy to abandon your usual diabetes management

routine. The hormones your body may produce in response to prolonged stress may prevent insulin

from working properly, which only makes matters worse. To take control, set limits. Prioritize your

tasks. Learn relaxation techniques. Get plenty of sleep.

Above all, stay positive. The good habits you adopt today can help you enjoy an active, healthy life

with type 1 diabetes.

PreventionBy Mayo Clinic staff

Controlling Your Diabetes

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There's no known way to prevent the type 1 diabetes. But researchers are working on preventing the

disease or further destruction of the islet cells in people who are newly diagnosed. Ask your doctor if

you might be eligible for one of these trials, but carefully weigh the risks and benefits of any

treatment available in a clinical trial.

You can find more information on the types of research being done from TrialNet, a collaboration of

diabetes researchers. TrialNet is also conducting a natural history study to check for diabetes genes

in parents, children and siblings of people with type 1 diabetes.

What is Type 1 Diabetes?The more severe form of diabetes is type 1, or insulin-dependent diabetes. It’s

sometimes called “juvenile” diabetes, because type 1 diabetes usually develops in

children and teenagers, though it can develop at any age.  

Immune System Attacks

With type 1 diabetes, the body’s immune system attacks part of its own pancreas.

Scientists are not sure why. But the immune system mistakenly sees the insulin-

producing cells in the pancreas as foreign, and destroys them. This attack is known

as "autoimmune" disease.

These cells – called “islets” (pronounced EYE-lets) – are the ones that sense glucose

in the blood and, in response, produce the necessary amount of insulin to normalize

blood sugars.

Insulin serves as a “key” to open your cells, to allow the glucose to enter -- and

allow you to use the glucose for energy.  

Without insulin, there is no “key.”   So, the sugar stays -- and builds up-- in the

blood. The result: the body’s cells starve from the lack of glucose.  

And, if left untreated, the high level of “blood sugar” can damage eyes, kidneys,

nerves, and the heart, and can also lead to coma and death. 

Insulin Therapy

So, a person with type 1 treats the disease by taking insulin injections.

This outside source of insulin now serves as the “key” -- bringing glucose to the

body’s cells. 

The challenge with this treatment is that it’s often not possible to know precisely

how much insulin to take. The amount is based on many factors, including:

Food Exercise Stress Emotions and general health

Balancing Act 

These factors fluctuate greatly throughout every day. So, deciding on what dose of

insulin to take is a complicated balancing act.  

If you take too much, then your body burns too much glucose -- and your blood

sugar can drop to a dangerously low level. This is a condition calledhypoglycemia,

which, if untreated, can be potentially life-threatening.  

If you take too little insulin, your body can again be starved of the energy it needs,

and your blood sugar can rise to a dangerously high level -- a condition

called hyperglycemia. This also increases the chance of long-term complications.