Association of A1C with cardiovascular disease and metabolic syndrome in Asian Indians with normal glucose tolerance.
OBJECTIVE
This study examines the association of A1C with cardiovascular disease (CVD) risk factors, coronary artery disease (CAD), and metabolic syndrome in Asian Indians with normal glucose tolerance (NGT).


METHODS
This cross-sectional study recruited subjects from phase III of the Chennai Urban Rural Epidemiology Study (CURES), an epidemiological study in a representative population of Chennai (formerly Madras) in South India, conducted between January 2003 and June 2004. Included were 1,644 subjects with NGT, i.e., fasting plasma glucose <100 mg/dl (5.6 mmol/l) and 2-h postload plasma glucose <140 mg/dl (7.8 mmol/l). A1C was measured using the Biorad Variant machine. Metabolic syndrome was defined based on modified Adult Treatment Panel III guidelines.


RESULTS
The mean +/- SD A1C value in the study cohort was 5.5 +/- 0.4%. A1C showed a significant association with BMI (beta = 0.017, P < 0.001), systolic (beta = 0.002, P = 0.028) and diastolic (beta = 0.202, P = 0.017) blood pressure, waist circumference (beta = 0.007, P < 0.001), serum cholesterol (beta = 0.002, P < 0.001), triglycerides (beta = 0.001, P < 0.001), LDL cholesterol (beta = 0.002, P < 0.001), fasting insulin (beta = 0.009, P < 0.001), and homeostasis model assessment of insulin resistance (beta = 0.047, P < 0.001) after adjusting for age and sex. Regression analysis showed that A1C had a strong association with metabolic syndrome that persisted after adjusting for age and sex (odds ratio [OR] 2.9 [95% CI 2.08-4.00]; P < 0.001). A1C also had a strong association with CAD (2.6 [1.23-5.63]; P = 0.01), but the significance was lost when adjusted for age and sex.


CONCLUSIONS
There is a strong association of A1C with prevalent CVD risk factors in Asian-Indian subjects with NGT.
Dilley
James
J
Madras Diabetes Research Foundation & Dr. Mohan's Diabetes Specialities Centre, Gopalapuram, Chennai, India.
Ganesan
Anbazhagan
A
Deepa
Raj
R
Deepa
Mohan
M
Sharada
Gopalakrishnan
G
Williams
O Dale
OD
Mohan
Viswanathan
V
D000328:Adult; D000704:Analysis of Variance; D044466:Asian People; D001786:Blood Glucose / Q000378:metabolism*; D049628:Body Size; D002318:Cardiovascular Diseases / Q000097:blood*; D015331:Cohort Studies; D003327:Coronary Disease / Q000097:blood / Q000175:diagnosis; D003430:Cross-Sectional Studies; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D007194:India; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood*; D008875:Middle Aged; D012016:Reference Values
D001786:Blood Glucose; D006442:Glycated Hemoglobin