Effect of age on pattern-reversal visual evoked potentials in Indian population

Abstract

Background and Aim: Functional declines of the visual system are probably the most obvious aging changes in humans. Normal non-pathologic aging causes senile miosis and media opacities which cannot entirely explain the age-related declines. Changes in the retina and its neuro-circuitary contribute to the visual decline, which can be evaluated by evoked potentials. We investigated the effects of age on various components of transient pattern-reversal visual evoked potentials (t-PRVEPs) and whether there is presence of any differential aging on t-PRVEPs in Indian population. Methods: Monocular t-PRVEPs of 292 eyes from 146 normal subjects living in Wardha, Maharashtra and whose age ranges from 1-75 years, were recorded on an evoked potential recorder. Differences in latencies and amplitude were analyzed using one way analysis of variance (ANOVA) and polynomial regressions. Results: Age affects the PRVEP components differently with the most significant changes encountered in the P100 amplitude. The present study demonstrated that statistically, at least 67% of these changes are contributed by age alone. Comparisons with studies abroad showed similar changes but suggest the existence of an aging difference in Indians by at least 5 years. Indian males and females also showed aging differences with the latter aging earlier by at least 6-7 years. Conclusion: We therefore conclude that Indians seem to age faster compared to other populations and further research on possible causes for this difference in aging is warranted.