Insulin resistance increases dyslipidemia-associated CHD risk
MedWire News: Findings from a US study suggest that incident coronary heart disease (CHD) risk associated with reduced high-density lipoprotein (HDL) cholesterol and elevated triglyceride levels is significantly increased in the presence of insulin resistance.
The researchers show that risk for CHD is nearly three times higher in individuals with insulin resistance and dyslipidemia (defined as lower-than-median HDL cholesterol or higher-than-median triglycerides levels), compared with those who do not have insulin resistance or dyslipidemia.
Writing in the journal Arteriosclerosis, Thrombosis, and Vascular Biology, the team says: "Our results appear to conform to more general studies showing that insulin resistance will independently predict the development of cardiovascular disease in general populations."
Sander Robins (Boston University, Massachusetts) and colleagues examined the effects of insulin resistance on the relationship between dyslipidemia and the development of CHD in nearly 3000 participants of the Framingham Heart Study who did not have diabetes.
A total of 128 individuals experienced an incident CHD event, defined as the first occurrence of nonfatal or fatal myocardial infarction or CHD death, during the mean 14-year follow-up period.
In the presence of insulin resistance, the 10-year incidence of CHD was 7% and 6% at lower-than-median levels of plasma HDL cholesterol and higher-than-median triglyceride levels, respectively, compared with just 2% in the absence of insulin resistance, and this remained significant after adjustments were made for major CHD risk factors.
Furthermore, in patients with insulin resistance, the risk for incident CHD was 2.83- and 2.50-times higher in those with lower HDL cholesterol or higher triglycerides, respectively, compared with the reference group (no insulin resistance or dyslipidemia).
In contrast, in the absence of insulin resistance there was no apparent increase in the risk for CHD, even in patients with dyslipidemia.
Robins et al stress that their results should not be interpreted to implicate insulin resistance as a direct cause of CHD events. However, they do say that instead of using measures of HDL cholesterol and triglycerides alone to identify individuals at high risk for CHD, it may be more suitable to use insulin resistance in conjunction with these lipid measurements.
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By Nikki Withers