Poor Contrast Sensitivity Predicts Subsequent Visual Acuity Loss in Patients Referred for Vision Rehabilitation

Abstract

Purpose:: To determine the association between measured contrast sensitivity at baseline and change in measured acuity between baseline and one year follow-up in patients referred for vision rehabilitation.

Methods:: 225 patients were enrolled in a one year prospective cohort study. Measured parameters included age, gender, acuity, contrast sensitivity, falls, hallucinations, depression, independence and time-trade.

Results:: After one year 19 were deceased, 54 were lost to follow-up and 152 patients were seen in follow-up. At baseline 33% of patients had > 6/18 acuity, no patients had > log 1.65 contrast sensitivity measured with Pelli-Robson chart and 52% had measured contrast sensitivity better than log 0.75. Considering log contrast sensitivity as a dichotomous variable (better than 0.75) measured contrast sensitivity at baseline was a significant predictor of subsequent change in visual acuity at one year. Odds ratio was 0.349 (95% confidence interval 0.144, 0.849) adjusting for baseline visual acuity (by quartiles), gender, age, falls, depression and hallucinations.

Conclusions:: Poor contrast sensitivity is a significant predictor of subsequent loss of acuity in patients undergoing vision rehabilitation.

Keywords: contrast sensitivity • low vision • visual acuity