Obesity, Diabetes, and Risk of Cardiovascular Disease in the Elderly

There is an age-related increase in total body fat and visceral adiposity until age 65 years that often is accompanied by diabetes or impaired glucose tolerance. The prevalence of type 2 diabetes increases progressively with age, peaking at 16.5% in men and 12.8% in women at age 75-84 years. Over age 65, diabetes or glucose intolerance was present in 30%-40% of Framingham Study subjects. There has been an alarming increase, of epidemic proportions, in both obesity and diabetes in the general population. Type 2 diabetes and obesity are both associated with a clustering of atherogenic risk factors, and when three or more are present it generally signifies an insulin resistance syndrome. This is promoted by weight gain and visceral adiposity. The risk of macrovascular disease is increased before glucose levels reach the diagnostic threshold for "diabetes," and 25% of newly diagnosed diabetics already have overt cardiovascular disease. In the Framingham Study, increased risk of cardiovascular disease was two-fold in men and three-fold in women, eliminating the female advantage over men for all outcomes except stroke. Coronary disease is the most common and lethal sequela, and unrecognized myocardial infarctions are three times more common in diabetic than nondiabetic men. Following a myocardial infarction, diabetes imposes a high rate of recurrence, heart failure, and death, more so in women than men. The risk of cardiovascular sequelae in diabetics is variable, the majority of events occurring in those with two or more additional risk factors. Because of the variable risk of cardiovascular disease in either the diabetic or obese person, risk stratification is necessary to determine the hazard of impending cardiovascular disease. This is readily accomplished with Framingham cardiovascular risk formulations. For persons with diabetes or obesity, the chief goal is to avoid the common cardiovascular sequelae. Comprehensive care should include not only normalization of the blood sugar, but also weight reduction, dietary fat restriction, strict blood pressure and lipid control, exercise, and avoidance of tobacco. Trial data indicate that preventive measures benefit obese diabetics even more than nondiabetics.