Overweight or obese people are at risk for myocardial infarction (heart attack) and ischemic heart disease (IHD) regardless of whether they also have the cluster of cardiovascular risk factors known as metabolic syndrome, which includes high blood pressure, high cholesterol and high blood sugar, a new study has revealed.

According to the study authors, being overweight or obese likely causes MI and IHD but whether co-existing metabolic syndrome is necessary for the conditions to develop is unknown.

Borge G. Nordestgaard, M.D., D. M.Sc., and Mette Thomsen, M.D., from Herlev Hospital, Copenhagen University Hospital, Denmark, investigated the associations by examining data from 71,527 participants in a general population study.

During nearly four years of follow-up, researchers identified 634 cases of MIs and 1,781 cases of IHDs. Relative to people with normal weight, the hazards of MI were increased with overweight and obesity and were statistically equivalent whether or not patients had metabolic syndrome.

There were also increasing cumulative incidences of MI and IHD among individuals both with and without metabolic syndrome from normal weight through overweight to obese individuals, according to the study results.

The study is published in JAMA Internal Medicine.