Aims: The aims of the study were to compare the recently evolved Indian Diabetes Risk Score (IDRS), in subjects with different grades of glucose intolerance and to evaluate its usefulness as an indicator of cardiovascular risk in Asian Indians, a high risk group for diabetes and coronary artery disease (CAD).
Methods: The data for the present study were obtained from the Phase 3 (n = 2350, response rate: 90.4%) of the Chennai Urban Rural Epidemiology Study, a population-based study done in Chennai, the largest city in southern India. IDRS was developed based on multiple logistic regression analysis using four simple parameters namely age, abdominal obesity, family history of type 2 diabetes and physical activity. In all subjects, family history of diabetes was obtained, and details on physical activity were assessed using a validated questionnaire. Subjects with an IDRS of <30 was categorized as low risk, 30-50 as medium risk and those with > or =60 as high risk for diabetes. Biochemical and anthropometric measurements were done using standardized procedures. Minnesota coding was used to grade 12-lead electrocardiogram.
Results: The mean IDRS increased significantly with worsening glucose intolerance [normal glucose tolerance (NGT) subjects: 48 +/- 17, impaired glucose tolerance (IGT): 57 +/- 16, newly diagnosed diabetics (NDD): 61 +/- 15 and known diabetics (KD): 68 +/- 12; p for trend <0.001]. Among NGT group, the prevalence of cardiovascular risk factors increased progressively in low-, medium- to high-risk score groups; hypertension: 9.4, 22.1 and 38.2% (p for trend: < 0.001), hypertriglyceridemia: 8.8, 19.9 and 25.3% (p for trend: < 0.001), hypercholesterolemia: 7.2, 20.3 and 34.9% (p for trend: < 0.001) and metabolic syndrome: 1.8, 14.6 and 30.3% (p for trend: < 0.001), respectively. The prevalence of CAD was also significantly higher in individuals with high risk compared with those with low risk (p = 0.030) and the medium risk (p = 0.050) in the NGT group.
Conclusions: The results suggest that in Asian Indians, (i) the diabetes risk score increases with increasing glucose intolerance, and (ii) it can serve as an effective indicator of metabolic syndrome and cardiovascular risk even among subjects with NGT.