Coronary Revascularization Outcomes Associated with HIV Infection

Joan C. Lo, UC Los Angeles

Numerous studies suggest an increased risk of coronary heart disease (CHD) in HIV-positive patients that may, in part, be attributable to differences in vascular risk factors and to the
atherogenic effects of protease inhibitor (PI) use. Given these factors and the aging HIVinfected
population in the era of highly active antiretroviral (ARV) therapy, coronary revascularization, including percutaneous coronary intervention (PCI) or coronary bypass graft surgery (CABG), may become increasingly common. However few studies have compared revascularization outcomes between HIV-positive and non-HIV patients. Prior studies on this topic are limited by small, selected samples with limited generalizability, and none have rigorously examined the effect of PIs. Therefore, the overall goal of this research is to determine whether HIV status and PI therapy are associated with adverse cardiovascular outcomes after coronary revascularization, including restenosis or repeat coronary revascularization, recurrent ischemia, or death. Using data from Kaiser Permanente Northern California (KPNC), with over 3.2 million adult members, the proposed study will represent the largest cohort to date of HIV-positive and non-HIV patients receiving coronary revascularization within a relatively unselected population. Long-standing, validated HIV and CHD registries and other automated data systems will be used to efficiently and robustly identify the study population, to ascertain clinical outcomes, and to collect demographic characteristics, known prognostic factors, ARV use and other HIV parameters.

Our Specific Aims are as follows:

  • To compare the initial clinical presentation of HIV-positive and HIV-negative patients who undergo coronary revascularization;
  • To determine whether HIV status is an independent predictor of adverse cardiovascular outcomes (restenosis or repeat coronary revascularization, acute myocardial infarction, unstable angina, or death) early (i.e., within the first 12 months) and late after coronary revascularization; and
  • To determine whether treatment with PIs is an independent predictor of adverse cardiovascular outcomes among HIV-positive patients after coronary revascularization.

The analytic approach will consist of standard longitudinal methods including Kaplan-Meier plots and multivariable Cox regression that will leverage the rich longitudinal data before and after individuals undergo coronary revascularization. Strengths of the proposed project include the large source population of patients receiving revascularization, the complete ascertainment of HIV patients and post-revascularization outcomes, the availability of relevant prognostic and confounding factors, and a highly generalizable population sample. This project utilizes the comprehensive health plan data sources within KPNC and brings together a multidisciplinary research team with complementary expertise, providing a unique setting to develop needed insights into appropriate treatment strategies for the growing population of HIV-positive patients requiring coronary revascularization. The established cohort will also provide a rich resource for future follow-up studies to investigate the mechanisms by which HIV and specific ARVs are associated with adverse cardiovascular outcomes and for evaluating the potential application of novel therapeutic approaches for CHD management.