Psoralen plus ultraviolet A does not increase the risk of cataracts: a 25-year prospective study

Abstract

Background: In some animal species, exposure of the unprotected eye to psoralen plus ultraviolet A (PUVA) therapy induces lens opacities. The relevance of these animal findings to human beings is not established. However, some case reports suggest that PUVA in human beings may increase the risk of lens abnormalities.

Objective: Our aim was to evaluate any possible associations between exposure to PUVA and increased risk of ocular lens abnormalities.

Methods: Since 1977 the PUVA follow-up study has periodically monitored the ocular status of 1237 cohort members with psoriasis using structured eye examinations. In our previous report we presented data results of the first 10 years of prospective study. This report includes data from two additional cycles of eye examinations that span an additional 14 years of follow-up.

Results: Based on our data from the last pre-1993 to final eye examination (2004), compared with that observed for the earlier period (first ever to last pre-1993 eye examination), the age-adjusted incidence of cataract did not increase significantly (incidence rate ratio = 1.04, 95% confidence interval = 0.82-1.31). In both the univariate and multivariate analyses increasing exposure to PUVA was not associated with a higher risk of cataract.

Limitations: Our cohort principally enrolled middle-aged or older patients so our data do not permit us to assess the effects of PUVA on the eyes of younger persons.

Conclusions: Increasing exposure to PUVA does not increase cataract risk among persons using eye protection at the rates used in our cohort.