Contrast Sensitivity and Color Vision in HIV-infected Individuals Without Infectious Retinopathy

Abstract

To investigate the relationship between abnormal contrast sensitivity and abnormal color vision among human immunodeficiency virus (HIV)-infected individuals who have normal visual acuity and to seek host factors that predict these abnormalities. Noninterventional, cross-sectional study. We evaluated 71 HIV-infected subjects with visual acuity of 20/25 or better, clear media, and no vision-threatening retinal lesions. Visual function was determined using the Pelli-Robson contrast sensitivity test and the Farnsworth-Munsell 100-Hue color test (FM-100). Results were compared with published values for normal populations and to measures of HIV disease severity. We evaluated two levels of impairment for each visual function. "Mild dysfunction" was defined as > or =1 standard deviation (SD), but <2 SD from normal means. "Abnormal" was defined as > or =2 SD from normal means. The prevalences of abnormal contrast sensitivity and abnormal color vision were 7.0% and 9.9%, respectively. We did not identify relationships between impaired contrast sensitivity and impaired color vision. Impaired color vision was associated with increasing age (r = 0.36, P = .002). We could not identify significant correlations between either contrast sensitivity or color vision values and the following factors: current or nadir (lowest previous) CD4+ T-lymphocyte count, HIV blood level, and Karnofsky score. Abnormal contrast sensitivity and abnormal color vision can occur independently in HIV-infected individuals and can be present in the absence of severe immunosuppression.