Prospective study of C-reactive protein in relation to the development of diabetes and metabolic syndrome in the Mexico City Diabetes Study

OBJECTIVE - Recent evidence suggests that C-reactive protein (CRP) may predict development of diabetes in Caucasian populations. We evaluated CRP as a possible risk factor of the development of diabetes and metabolic syndrome in a 6-year study of 515 men and 729 women from the Mexico City Diabetes Study. RESEARCH DESIGN AND METHODS - Baseline CRP, indexes of adiposity, and insulin resistance (homeostasis model assessment [HOMA-IR]) were used to predict development of the metabolic syndrome defined as including two or more of the following: 1) dyslipidemia (triglyceride greater than or equal to2.26 mmol/l or HDL cholesterol less than or equal to0.91 mmol/l in men and less than or equal to1.17 mmol/l in women; <35 and 40 mg/dl for men and women); 2) hypertension (blood pressure > 140/90 mmHg or on hypertensive medication); or 3) diabetes (1999 World Health Organization criteria). RESULTS - At baseline, CRP correlated significantly (P < 0.001) with all metabolic indexes in women, but less so in men. After 6 years, 14.2% of men and 16.0% of women developed the metabolic syndrome. Compared with tertile 1, women with CRP in the highest tertile had an increased relative risk of developing the metabolic syndrome by 4.0 (95% CI 2.0-7.9) and diabetes by 5.5 (2.2-13.5); these risks changed minimally after adjusting for BMI or HOMA-IR. The area under receiver-operating characteristic (ROC) curve for the prediction of the development of the syndrome was 0.684 for CRP, increasing to 0.706 when combined with BMI and to 0.710 for a complex model of CRP, BMI, and HOMA-IR. CONCLUSIONS - CRP was not a significant predictor of the development of the metabolic syndrome in men. Our data strongly support the notion that inflammation is important in the pathogenesis of diabetes and metabolic disorders in women.