Early Retinal Vascular Abnormalities in African-American Cocaine Users

Abstract

Purpose-To evaluate early changes in the central retinal response in HIV positive patients without infectious retinitis using multifocal electroretinography (mfERG).Design-The study was a case control study.Methods-We evaluated three cohorts -HIV negative controls and two groups of HIV positive patients separated according to their nadir CD4 counts (≥100 and <100 for a minimum of 6 months). MfERG first (FOK) and second order (SOK) kernels were analyzed separately by areas of rings, quadrants and individual hexagons for each cohort.Results-Of 103 hexagon locations of FOK results there were no significant differences in amplitudes of P1 and N1 across the groups (0.05<p<0.50); although there was a trend for an overall reduction in the amplitudes. Similarly, latency N1 did not differ (0.28<p<0.95). There were significantly delayed latencies of P1 between cohorts across 103 hexagons in both kernels. SOK results also showed significant delay in latencies of P1 and a trend of reduced P1 amplitudes across studied locations among cohorts (0.24<p<0.08).Conclusion-The results demonstrate widespread delay in latency in HIV positive patients, especially in those with prolonged low (below 100) CD4 nadir counts. These findings suggest early diffuse dysfunction of the inner retina resulted from severe HIV disease even in the era of HAART.

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Ocular manifestations of drug and alcohol abuse

“…[34] In a study comparing African-American patients who used cocaine with those who did not use cocaine, investigators found a wider retinal venular caliber and increased arterial branching, and proposed this may reflect more generalized central nervous system (CNS) microvascular disease. [35]…”