Schizophrenia

Pallav Pareek M.D

HISTORY

Benedict Morel French 1809-1873, gave the term Demence Precoce

Emil Kraepelin German 1856-1926, furthered Morel’s work.

Father of Psychiatry, first doctor to differentiate the two major types of Psychosis , Maniac Depressive Psychosis, and Dementia( Distinct Cognitive Process) Precox( early onset) : He described them as having an early age of onset, long term detiriorating course and common symptoms of Hallucinations and delusions

Eugen Bleuler Swiss 1857-1939 Bleuler realized the condition was neither a dementia nor did it always occur in young people (praecox meaning early) and so gave the condition the purportedly less stigmatising but still controversial name from the Greek roots schizein "to split“ and phrēn, "mind“ . By Schizophrenia he meant a schism between thought, emotion and behavior

Kretschmer compiled data about personality types schizophrenia occurs more in the Asthenic a.k.a Leptosomic ( slender, lightly muscled physiques) Athletic or Dysplastic( a mixture of a few body types) body types, while the Pyknik body types (short, stocky) more commonly have mania/depression

Epidemiology

Prevalence : 1% except certain pockets like Ireland.

Equal distribution: M & F M: MAO: 15-25 F : MAO: Bimodal 25-35 ,

and then a second peak near menopause

Onset before and after 10-60 years extremely rare, If the onset is after 45 it’s called late onset SCZ

Etiology

Birth Season: Jan to April, Southern July to

September VIRAL HYPOTHESIS talks about viral (retroviruses) infection or virally activated autoimmune reactions which produce antibrain antibodies.

Cigarette smoking

75% SCZ patients are smokers , compare to 50% All Psych Patients , and 20.8% in General Population ( United states 2007 Source: Center for Disease Control and Prevention)

Smoking increases the metabolism – High Antipsychotic requirement

FACTS

WHY SCZ SMOKE SO MUCH Smoking reduces the drug related

parkinsonian effects ( Nicotine activates the DA in NIgrostriatal pathways)

Nicotine also Increases the threshold for perception of outside stimuli ( is very low in SCZ), thereby relieves symptoms such as Hallucinations, thus acts as a self medication for Patients

Socioeconomic factors

Downward Drift Hypothesis: ( More popular hypothesis) Affected people move into or fail to rise from Low SE Status

Social Causation Hypothesis: Stress experienced in Low SE groups may be a cause

Neurobiological Models

Pruning Hypothesis: Several lines of evidence support the notion that a substantial reorganization of cortical connections, involving a programmed synaptic “pruning”, takes place during adolescence in humans( Proposed reason for SCZ starting after a certain age). A review of neurobiological abnormalities in schizophrenia indicates that the neurobiological parameters that undergo peripubertal regressive changes may be abnormal in SCZ. An excessive pruning of certain areas of the Brain, may underlie schizophrenia.

DOPAMINE Hypothesis

Too much Dopaminergic activity Reasons to support1. Efficacy of

antidopaminergic( antipsychotic) drugs which act on D2 Receptors

2. Drugs which Increase DA, viz Amphetamines are Psychotomimetic

3. Plasma HVA levels , are proportionately higher in symptom severity of SCZ

Other NT’s Variously IMPLICATED NE Serotonin GABA Glutamate

Various Structural abnormalities in SCZ Brains Increased Ventricle Size Reduced Frontal lobe size ( and

activity) Decrease in Limbic System Size

Genetic Factors

Almost half the chromosomes have been implicated

Current Research focuses onLong Arm 5 11 18Short Arm 19 and X

Freud’s Explanation EGO DEFECT According to Freud, schizophrenia is a form

of regression “ back to the oral stage of development.  The oral stage is the first stage of psychosexual development.  A baby is born a bundle of id “ is self-indulgent and concerned only with a satisfaction of his/her needs.  People with schizophrenia are overwhelmed by anxiety because their egos are not strong enough to cope with id impulses.  In schizophrenia, this can lead to self-indulgent symptoms such as delusions of grandeur

Prevalence

General Population

Nontwin Sibling One Parent with Dizygotic Twin Two Parents Monozygotic Twin

1% 8% 12% 12% 40% 47%

DSM IV TR Criteria for SchizophreniaA) ( The criterion A ) Characteristic Symptoms: Two

( or more ) of the following each present for a significant portion of time during a one month period ( or less if treated successfully)

1. Delusions2. Hallucinations3. Disorganized Speech ( e.g frequent

derailment or incohrence)4. Grossly disorganised or catatonic

behavior5. Negative Symptoms ( flat affect, social

withdrawl, poverty of speech,

B) Social/Occupational Dysfunction: for a significant portion of time since illness, disturbance in work, interpersonal relations, and self care.

C) Duration: Persists for at least 6 months,with 1 Month of Active symptoms ( May be less if the pt recieve RX)

D) Exclude Schizoaffective and Mood disorders

E) Report Substance/GMC F) No History of Autism/PDD

Classification Of Longitudinal Course (If duration is > 1 Year) Episodic with interepisode residual

symptoms Episodic with no interepisodic Symptoms Continous ( prominent psychotic

symptoms throughout observed period) Single episode in full remission Single episode in partial remission Other or Unspecified Pattern

Types of SCZ

Paranoid Disorganised Catatonic Undifferentiated Residual

Paranoid type

Following criteria are met A) Preoccupation with one or more

delusions or auditory hallucinations B) None of the following is prominent

– disorganised speech, disorganised or catatonic behaviour , flat or inaapropriate effect

Disorganised Type

* Following criteria are met A) All of the following are prominent1. Disorganised speech2. Disorganised behavior3. Flat or inappropriate effect

B) Criteria for catatonic are not met

Catatonic Type

Two of the following are present1. Motoric immobility as evidenced by catalepsy or

stupor ( including Waxy Flexibility)2. Excessive Motor Activity. Is apparently

purposeless and not influenced by external stimuli

3. Extreme Negativism( an apparently motiveless resistance to all instuction ot maintenance of a rigid posture against attempts to be moved) or Mutism

4. Peculiarities of Voluntary movement as evidenced by posturing, stereotyped movements, prominent mannerisms or prominent grimacing

5. Echolalia or Echopraxia

Undifferentiated Type

Symptoms of Schizophrenia are met, but criteria for Paranoid, Disorganised or Catatonic type are not met

Residual Type

Following criteria are metA. Absence of prominent delusions,

hallucinations, disorganised speech , and grossly disorganised or catatonic behavior

B. There is evidence of disturbance, as indicated by Negative Symptoms , or two or more symptoms listed in Criterion A