Retinal Vessel Caliber Among People With Acquired Immunodeficiency Syndrome: Relationships With Disease-Associated Factors and Mortality

Abstract

To evaluate relationships between retinal vessel caliber, AIDS-related factors, and mortality. Longitudinal, observational cohort study. We evaluated data for participants without ocular opportunistic infections at initial examination (baseline) in the Longitudinal Studies of the Ocular Complications of AIDS (1998-2008). Semi-automated evaluation of fundus photographs (1 eye/participant) determined central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and arteriole-to-venule ratio (AVR) at baseline. Multiple linear regression models, using forward selection, identified independent relationships between indices and various host- and disease-related variables. Included were 1250 participants. Mean follow-up for determination of mortality was 6.1 years. Smaller CRAE was related to increased age (P < .001) and hypertension (P < .001); larger CRAE was related to lower hematocrit (P = .002). Larger CRAE and CRVE were associated with black race (P < .001). Larger CRVE was related to smoking (P = .004); smaller CRVE was related to age (P < .001) and higher mean corpuscular volume (P = .001). We observed the following relationships with AIDS-associated factors: smaller CRAE and larger CRVE with history of highly active antiretroviral therapy (HAART; P < .001); and larger CRAE with lower CD4+ T lymphocyte count (P = .04). We did not identify independent relationships with human immunodeficiency virus RNA blood levels. There was a 12% (95% CI, 2%-21%) increase in mortality risk per quartile of decreasing AVR (P = .02). Variations in retinal vascular caliber are associated with AIDS-specific factors and are markers for increased mortality risk. Relationships are consistent with the hypothesis that the vasculature is altered by known atherogenic effects of chronic HAART or the prolonged inflammatory state associated with AIDS.