Metabolic syndrome and Framingham risk score for prediction of cardiovascular events in Caribbean Indian patients with blood glucose abnormalities

Abstract

Objective To evaluate the metabolic syndrome (MS) and Framingham risk score (FRS) as predictors of cardiovascular (CV) events in Caribbean Indian patients who have type 2 diabetes (T2D) or impaired glucose tolerance (IGT). Method A longitudinal and retrospective study was conducted involving patients classified as T2D or IGT in a first study in 1997 who responded for a second examination in 2006. Nonparametric tests and Cox's proportional hazards model were used. Hazard ratios (HRs) and their confidence intervals (95% CI) for risk of a first CV event, according to the presence of MS or a high FRS, were estimated. For MS, the models were adjusted for age, gender and smoking status. Results A total of 148 patients were included in the present study. The mean time without a CV event was 7.5 years (range 0.38–8.45 years). We noted 31 (25 nonfatal) first hospitalizations, for stroke ( n = 15), angina pectoris ( n = 8), acute coronary heart disease ( n = 7) and acute peripheral vascular disease ( n = 1). Ten (6.8%) patients died and six deaths were related to CV events. The HRs of CV events associated with metabolic syndrome, defined by the National Cholesterol Education Program's Adult Treatment Program III, were not significant. Conversely, HRs of CV events associated with the FRS were 4.78 (95% CI 1.65–13.5) and 2.94 (95% CI 1.42–6.06) for a risk score superior or equal to 10% and superior or equal to 20%, respectively. For coronary heart disease alone, the HRs associated with the FRS were 9.92 (95% CI 1.31–75.2) and 2.88 (95% CI 1.05–7.93), respectively. In these Caribbean Indian patients with blood glucose abnormalities, unlike the FRS, MS failed to identify subgroups at high cardiovascular risk in the short term (8.5 years). Nevertheless, the long-term risk-predictive value of these tools needs to be evaluated.