Elevated triglycerides and risk of myocardial infarction in HIV-positive persons

OBJECTIVES: To explore the relationship between elevated triglyceride levels and the risk of myocardial infarction (MI) in HIV-positive persons after adjustment for total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C) and nonlipid risk factors. BACKGROUND: Although elevated triglyceride levels are commonly noted in HIV-positive individuals, it is unclear whether they represent an independent risk factor for MI. METHODS: The incidence of MI during follow-up was stratified according to the latest triglyceride level. Multivariable Poisson regression models were used to describe the independent association between the latest triglyceride level and MI risk after adjusting for TC and HDL-C, nonlipids cardiovascular disease (CVD) risk factors, HIV and treatment-related factors. RESULTS: The 33,308 persons included in the study from 1999 to 2008 experienced 580 MIs over 178,835 person-years. Unadjusted, the risk of MI increased by 67% relative risk (RR) 1.67, 95% confidence interval 1.54-1.80 per doubling in triglyceride level. After adjustment for the latest TC and HDL-C level, the RR dropped to 1.33 (95% confidence interval 1.21-1.45); this effect was further attenuated by other CVD risk factors and the RR was reduced to 1.17 (95% confidence interval 1.06-1.29). In models that additionally adjusted for HIV and treatment factors, the risk was further diminished, although remained significant (RR 1.11, 95% confidence interval 1.01-1.23). CONCLUSION: Higher triglyceride levels were marginally independently associated with an increased risk of MI in HIV-positive persons, although the extent of reduction in RR after taking account of latest TC, latest HDL-C and other confounders suggests that any independent effect is small.