High triglycerides tied to mortality in coronary heart disease

Severe hypertriglyceridemia significantly increased the long term risk of death among patients with established coronary heart disease, even after low-density lipoprotein cholesterol was accounted for, according to a large prospective study.

“This effect is graded – the higher the independent mortality risk,” said Sheba Medical Center in Tel-Hashomer, Israel.

Thus, patients whose triglycerides measured at least 500 mg/dL were 68 percent more likely to die in the next two decades than were patients with triglycerides levels of less than 100 mg/dL. The relative increase in risk was 29 percent for patients with levels between 200 and 499 mg/dL and 16 percent for those with levels between 150 and 200 mg/dL.

Prior studies of hypertriglyceridemia in patients with established congenital heart disease have been small, with short follow-up periods and inconclusive results. Therefore, they analyzed national registry mortality data and fasting triglyceride levels for 15,355 patients who had been screened for the Bezafibrate Infarction Prevention trial during 1990 and 1992. They grouped patients as low-normal (less than 100 mg/dL); high-normal (100-149 mg/dL); borderline hypertriglyceridemia (150-199 mg/dL); moderate hypertriglyceridemia (200-499 mg/dL); and severe hypertriglyceridemia (at least 500 mg/dL).

After researchers adjusted for age and sex, the overall survival rate during 22 years of follow-up was 41 percent in the low-normal triglycerides group and 37 percent, 36 percent, 35 percent, and 25 percent in the higher triglycerides cohorts, respectively. In the adjusted model, each one-unit natural logarithm increase in triglycerides corresponded with a six percent rise in the 22-year-risk of all-cause mortality.

Limited follow-up data after screening prevented the researchers from controlling for a variety of confounders, but the results nonetheless support consideration for lower triglyceride targets and highlight the need for prospective studies in “appropriately selected subjects.”