Random fasting hyperglycemia as cardiovascular risk factor in the elderly: a 6-year longitudinal study

A large body of evidence suggests that diabetes increases the risk of coronary heart disease (CHD), but whether fasting hyperglycemia is associated with a major risk for CHD is still under debate. The aim of the present study was to investigate the role played by fasting hyperglycemia in the development of cardiovascular disease (CVD) in an elderly population when associated with common risk factors for CVD (i.e., hypertension, hypercholesterolemia, smoking, etc). We analyzed a sample of 455 subjects aged > or = 60 years. The risk factors taken into account were systolic and diastolic blood pressure levels, use of antihypertensive drugs, total serum cholesterol, serum triglycerides, and smoking habit. Glycemia was measured at entry on a fasting sample. During the follow-up period (mean 6 years), the occurrence of CVD was monitored (criteria for the occurrence of CVD included total cardiovascular mortality, fatal or nonfatal myocardial infarction, symptomatic coronary heart disease [stable and unstable angina], the need for percutaneous transluminal coronary angioplasty or coronary artery bypass graft, fatal or nonfatal stroke, and transient ischemic attack). A total of 427 subjects completed the follow-up. During this period, 73 subjects (17.10%) developed CVD according to the above criteria. A Cox proportional hazard model was designed to evaluate the contribution of variables in predicting CVD. Relative risks and 95% confidence intervals for CVD were calculated from the regression coefficients to study the association between the risk of developing CVD and predicting variables. We found a relation between occurrence of CVD and fasting hyperglycemia: subjects with fasting glycemia, > 126 mg/dl at enrollment, but without previous clinical diagnosis of diabetes, showed a 2.01 times higher risk than those with fasting glycemia < 126 mg/dl. Hence, random fasting hyperglycemia can predict the occurrence of CVD in elderly subjects.