Risk Factors for Posterior Subcapsular Cataract in Retinitis Pigmentosa.

Purpose: Posterior subcapsular cataract (PSC) is a frequent complication in patients with retinitis pigmentosa (RP). The risk factors for PSC formation in RP are largely unknown. The purpose of this study was to investigate the risk factors for PSC. Methods: We retrospectively studied a total of 322 eyes of 173 patients who were diagnosed with typical RP. We considered the following possible risk factors for PSC: age, sex, hypertension, diabetes mellitus, high myopia, asthma, history of steroid intake, and aqueous flare. Aqueous flare values were measured consecutively in 2012 and 2013 using a laser flare cell meter. The lens including PSC was examined with a slit lamp after dilation with tropicamide 1% and phenylephrine 2.5%. Results: The geometric mean values of aqueous flare and mean values of visual acuity were significantly higher for the RP patients with PSC compared to those without PSC (P = 0.0003, P = 0.0004, respectively). When the aqueous flare values were assessed continuously, each 1-log-transformed increase in flare levels was associated with an elevation of the likelihood of having PSC after multivariable adjustment (odds ratio: 1.71; 95% confidence interval: 1.05-2.77). There were no significant associations of the other possible risk factors with PSC. Conclusions: Our analysis demonstrated that elevated aqueous flare is a significant risk factor for PSC formation. This result might provide insights into the association of inflammation and the pathogenesis of PSC formation in RP.