Background: Peripheral arterial disease (PAD) affects ~8 to 10 million U.S. adults annually and is the second most common clinical manifestation of atherosclerosis after acute myocardial infarction (AMI). While the increased risk of AMI and ischemic stroke among HIV infected (HIV+) compared to uninfected people is well documented, data linking HIV to incident PAD events are sparse. We, therefore, compared PAD risk among HIV+ and uninfected veterans.
Methods: We analyzed data on 91,457 veterans (33% HIV+) without prevalent cardiovascular disease from the Veterans Aging Cohort Study (VACS). VACS is an observational, longitudinal cohort of HIV+ veterans matched 1:2 with uninfected veterans on age, gender, race/ethnicity, and clinical site. Participants were followed from their first clinical encounter on or after 4/1/2003 until a PAD event, death, their last follow-up date, or 9/30/2012. We used ICD-9 and CPT codes to identify participants with incident PAD. Cox proportional hazard regression models were utilized to assess the association between HIV, CD4+ T cell count, and PAD adjusting for atherosclerotic risk factors (Table). Finally, we constructed cumulative incidence curves to examine PAD risk stratified by HIV status and CD4 + T cell count.
Results: During a median follow-up of 7 years, there were 5091 PAD events. See Table and Figure for rates and risk of PAD stratified by HIV status and CD4+ T cell count.

GroupNPAD EventsRate/1000PY 95% CI]Unadjusted PAD Risk [HR 95% CI]Adjusted PAD Risk [HR 95% CI]a
HIV Uninfected61,49831038 [7.8, 8.4]1.001.00
HIV+, CD4: 500+10,68266310 [9.4, 11.0]1.23 [1.13, 1.34]1.31 [1.20, 1.43]
HIV+, CD4: [200, 500)12,36883511 [10.6, 12.1]1.41 [1.31, 1.52]1.46 [1.35, 1.59]
HIV+, CD4: <200690949014 [12.8, 15.3]1.77 [1.60, 1.95]1.62 [1.45, 1.80]
a adjusted for age, sex, race/ethnicity, hypertension, diabetes, LDL and HDL cholesterol, triglycerides, HCV infection, smoking status, renal disease, BMI, anemia, cocaine dependence or abuse, alcohol dependence or abuse, and COPD.
[Rates and risk of PAD by HIV status and CD4+ T cel]


Conclusions: Conclusions and Relevance: HIV+ veterans have a significantly higher risk of PAD than uninfected veterans.