New research indicates development of insulin resistance increases a person's risk for development of congestive heart failure, according to a study in the July 20 issue of JAMA.
Congestive heart failure (CHF) is a major cause of illness and death, according to background information in the article. The death rate for patients with CHF is 4 to 8 times that of the general population. The predominant causes of heart failure are hypertension and coronary heart disease.
Other established risk factors for CHF include diabetes and obesity, and both are associated with insulin resistance. More detailed characterizations of the association between diabetes and subsequent CHF are still lacking. In patients with manifest CHF, insulin resistance is associated with more-severe disease and a worse prognosis, but insulin resistance has not been investigated as a predictor of CHF.
Erik Ingelsson, M.D., of Uppsala University, Sweden, and colleagues conducted a study to examine whether insulin resistance is a predictor of CHF and is a link between obesity and CHF. The study, conducted in Uppsala, Sweden, included 1,187 elderly (70 years of age or older) men free from CHF and valvular disease at baseline between 1990 and 1995, with follow-up until the end of 2002. Variables reflecting insulin sensitivity and obesity were analyzed together with established risk factors (prior myocardial infarction, hypertension, diabetes, electrocardiographic left ventricular hypertrophy, smoking, and serum cholesterol level) as predictors of subsequent incidence of CHF.
One-hundred four men developed CHF during a median (middle value) follow-up of 8.9 years. "In this community-based sample of elderly men free of CHF and valvular disease at baseline, insulin resistance predicted CHF incidence independently of diabetes and other established risk factors for CHF," the authors write. "The previously described association between obesity and subsequent CHF may be mediated largely by insulin resistance. Further studies are needed to confirm our findings."