Etiology of type 2 diabetes mellitus

1. DIABETOGENIC LIFESTYLE - (ie, excessive caloric intake, inadequate caloric expenditure, obesity) - BMI at which excess weight increases risk for diabetes varies with different

racial groups:

Persons of Asian ancestry are at increased risk for diabetes at lower levels of overweight compared to Europeans.

Hypertension and prehypertension are associated with a greater risk of developing diabetes in whites than in African Americans.

- In addition, an in utero environment resulting in low birth weight may predispose some individuals to develop type 2 diabetes mellitus.

- Infant weight velocity has a small indirect effect on adult insulin resistance

2. GENETIC INFLUENCES

- The genetics of type 2 diabetes are complex and not completely understood.

- multiple genes in pancreatic beta-cell failure and insulin resistance but the one with the strongest effect on susceptibility is the transcription factor 7–like 2 (TCF7L2) gene .

-The syndrome historically known as maturity onset diabetes of

youth (MODY) ,autosomal dominant a variety of defects in beta-cell function

- 2-5% of individuals with type 2 diabetes who present at a young age and have mild disease.

3. DEPRESSION - Antidepressant use may be a marker of more severe, chronic, or

recurrent depression - may increase diabetes risk, possibly by altering glucose

homeostasis or promoting weight gain.

4. SCHIZOPHRENIA =Schizophrenia is a mental disorder often characterized by abnormal social behavior and

failure to recognize what is real. Common symptoms include false beliefs, unclear or confused thinking,

auditory hallucinations, reduced social engagement and emotional expression, and inactivity

- risk for type 2 diabetes. - Dysfunctional signaling involving protein kinase B (Akt) is a possible

mechanism for schizophrenia - acquired Akt defects are associated with impaired regulation of

blood glucose

5. Pre-eclampsia and gestational hypertension =preeclampsia is a disorder of pregnancy characterized by high blood pressure and large

amounts of protein in the urine.

=Gestational hypertension or pregnancy-induced hypertension (PIH) is defined as the development of new arterial hypertension in a pregnant woman after 20 weeks gestation without the presence of protein in the urine

- Pregnant women with either preelampsia or gestational hypertension have higher risk to develop type 2 diabetes.