914 HIV Patients have More Thromboembolic Events than Controls Which are Associated with Poorer Survival S. L. Fultz*1,2, A. C. Justice1,2, K. A. McGinnis1, M. Skanderson1, M. V. Ragni2,3 1Veterans Admin Pittsburgh Hlthcare Sys, PA; 2Univ of Pittsburgh Sch of Med, PA; and 3Hemophilia Ctr of Western Pennsylvania, Pittsburgh, PA
Objectives: Preliminary studies have suggested that HIV+ individuals are at an increased risk of thromboembolic events but these studies have been limited in size and populations studied. Our objectives are to determine if the rate of thromboembolic events in veterans differed by HIV status, and if these differences were affected by the introduction of highly active antiretroviral therapy (HAART).
Methods: Male HIV+ veterans ages 25-85 yrs, along with age-, race-, and site-matched controls were identified from VA administrative databases. Demographic characteristics, diagnostic codes for thromboembolic events, atrial fibrillation, AIDS-related opportunistic infections, cancer and use of central venous catheters, and dates of death were extracted. Poisson regression was used to determine the rate ratios of first thromboembolic event of HIV+ patients to HIV- controls. Cox proportional hazards models were used to determine if thrombosis was associated with survival.
Results: We identified 15,621 HIV+ subjects and 14,854 controls in the pre-HAART period and 31,496 HIV+ subjects and 36,053 controls post-HAART. Pre-HAART, 2.0 % of HIV+ and 1.4% of HIV- veterans had at least 1 thromboembolic event, and post-HAART 1.7% of HIV+ and 1.0% of HIV- veterans had at least 1 thromboembolic event. Poisson regression demonstrated increased rates of thromboembolic events in HIV+ subjects in both time periods (pre-HAART Standardized Incidence Ratio [SIR] 1.40, p < 0.001, and post-HAART SIR 1.37, p < 0.001). Cancer, AIDS-related opportunistic infections, atrial fibrillation, and venous catheters were all associated with thromboembolic events; however, the results did not change significantly after controlling for these diagnoses. Thrombosis was associated with survival pre-HAART and post-HAART in both the HIV+ subjects and the HIV- controls.
Conclusions: HIV-infected veterans experience a 40% increased risk of thromboembolic events both pre- and post-HAART. This finding remains statistically significant when controlling for cancer, AIDS-related opportunistic infection, atrial fibrillation, and venous catheters. In addition, the occurrence of thrombosis was associated with poorer survival in all groups. Identification of this increased risk of thromboembolism should lead to further investigation into the pathophysiology of thrombosis in HIV and should alert clinical providers to the increased risk among HIV+ patients.
