Abstract 11139: Prevalence, Characteristics and Prognostic Associations of Carotid Plaque Among HIV-infected Subjects Free of Known Cerebrovascular Disease

Abstract

Introduction: The risk of cerebrovascular events is increased among HIV-infected subjects; this risk is independent of conventional cardiovascular (CV) risk factors and may be related to persistent inflammation leading to accelerated carotid atherosclerosis. However, there are no data characterizing the prevalence, characteristics and prognostic associations of carotid plaque among subjects with HIV. Methods: From a clinical registry, we identified all HIV-infected subjects with a CT neck from 2005-2014. Data collection and CT analysis were performed by blinded independent teams and included CV and HIV specific risk factors. CT variables included presence of carotid plaque, plaque composition (calcified/non-calcified/mixed), degree of stenosis [≥ 50%] and high-risk plaque (HRP) features [low attenuation, spotty calcification]. The outcome was a cerebrovascular event (stroke, transient ischemic event) defined by ICD codes and independently adjudicated by a board certified physician. Association between plaque presence, characteristics and HRP with events was tested by Cox proportional hazard models. Results: Of 231 HIV-infected subjects, 32 had prior cerebrovascular disease,15 had poor image quality leaving an n=184 (46±10 yrs, 21% female,12% diabetics, 19% HTN, smoking in 31%, 14% on statins, average LDL of 90±39mg/dl). On CT, 36% had any carotid plaque and 23% had bilateral plaque. Of those with plaque,15% had a stenosis of ≥50% and 70% had any HRP feature. Both plaque and HRP were increased with age, duration of HIV and anti-retroviral therapy. Over a median of 4 yrs,13 (7%) cerebrovascular events occurred. After adjusting for the number of CV risk factors, a carotid plaque [HR: 3.5 (1.1-11) P =0.03, Fig 1A] and any HRP feature [HR: 3.2 (1.0-10) P =0.04, Fig 1B] were associated with incident cerebrovascular events. Conclusions: Among HIV-infected subjects, free of known cerebrovascular disease, carotid plaque and/or HRP predict cerebrovascular events.