Heart attack patients with diabetes or a cluster of cardiovascular risk factors known as metabolic syndrome have an increased risk of another heart attack, stroke or death, but patients who lost weight after their heart attacks were less likely to become diabetic, according to a new study in the July 19, 2005, issue of the Journal of the American College of Cardiology.
“Metabolic syndrome had a strong impact in the prognosis of patients with previous heart attack,” said Roberto Marchioli, M.D., at the Consorzio Mario Negri Sud in Santa Maria Imbaro, Italy. “The diagnosis of metabolic syndrome in post-heart attack patients indicated a high risk of cardiovascular events as well as of late onset diabetes. But the study also showed that weight reduction in overweight metabolic syndrome patients had a favorable impact on prognosis,” he said.
“The most important clinical consequence of this analysis is that lifestyle modification (for example, weight reduction) has a very favorable prognosis in overweight metabolic syndrome patients. Patients who achieved even modest weight reduction significantly reduced their risk of late onset diabetes,” Dr. Marchioli said.
Metabolic syndrome is characterized by a cluster of risk factors related to insulin resistance and is considered to be an early indicator of impaired glucose metabolism; thus, these patients are at high risk of developing diabetes, which is strongly related to heart disease risk.
The researchers, including lead author Giacomo Levantesi, M.D., analyzed data on 11,323 patients who had suffered a recent heart attack. The information was originally collected as part of the GISSI-Prevenzione Study that was designed to study the effects of polyunsaturated fatty acid and vitamin E supplements on heart attack patients.
“It is the largest analysis that allows us to assess the impact of metabolic syndrome in patients with established coronary artery disease. Up to now, evidence on the role of metabolic syndrome in cardiovascular disease came mainly from studies in primary prevention; that is, preventing the first heart attack, and the real impact of metabolic syndrome in a large population of post-heart attack patients had not been studied before,” Dr. Marchioli said.
At the start of the study, about one in five (21 percent) of the heart attack patients had diabetes. Almost one in three (29 percent) had metabolic syndrome, and by the end of follow-up three-and-a-half years later, the patients with metabolic syndrome were almost twice as likely to develop diabetes (93 percent) as were the patients without metabolic syndrome.