Diabetes is a chronic disease that will lead to complication in multiple organs in the body on long term especially if poorly controlled. Global increase in diabetes is due to population ageing, sedentary life style, obesity and altered dietary habits.
Type 2 diabetes remain undiagnosed until the complication develops. One third of people living with diabetes is undiagnosed. Sceening program will help in detecting early recognition of diabetes. All those people who are at high risk for developing diabetes should be screened.
Criteria for screening asymptomatic people.
(a) Individual at 45 years and above particularly if BMI more than 25kg/m2. If normal it should be repeated at 3 yearly interval.
(b) Testing should be done in younger age especially if they have risk factors.
1. Physically inactive.
2. First degree relatives with diabetes mellitus.
3. Members of high risk ethnic group such as African Americans, Native American, Lation, Asian American, Pacific Islander.
4. Females with history of gestational diabetes or delivered a baby more than 9 lb.
5. Females with polycystic ovarian syndrome.
6. Hypertensive people with BP more than 140/90 mm of Hg.
7. Those with Triglyceride more than 250mg/dl or HDL cholesterol less than 35 mg/dl.
8. Previous test showed impaired glucose tolerance or fasting glucose.
9. People with other clinical features of insulin resistance eg. Acanthosis Nigricans.
10. People with heart disease.
Screening test
To detect future diabetes the following test are used
Fasting glucose test(FBS)
Oral glucose tolerance test ( 2 hours after taking 75gm of glucose blood test is done).
The cumulative incidence of diabetes over 5-6 yrs based on above test Normal FBS, normal oral glucose tolerance - low risk 4 - 5%.
Impaired FBS, normal oral glucose tolerance - intermediate risk 20-34%.
Normal FBS, Impaired oral glucose tolerance - intermediate risk 20-34%.
Impaired FBS, Impaired oral glucose tolerance - 38-65%.
Blood glucose level 2 hours after food intake (postprandial blood sugar )is directly related to the mortality and morbidity in heart disease, so 2 hour oral glucose tolerance test is done as screening procedure in people with heart disease.
Fasting glucose test is more convenient to people, more reproducible and cost effective hence ADA recommend fasting blood glucose test as the screening test.
