Background: To evaluate whether the presence of psoriasis increases the risk of keratopathy incidence by using Taiwan's National Health Insurance Research Database (NHIRD).
Methodology/principal findings: This retrospective cohort study used data from the NHIRD for the 2009 to 2012 period. A total of 3,648 patients diagnosed with psoriasis were enrolled in the study group while another 14,592 individuals were selected as the control group. The study group was propensity score-matched with a group of controls who had not received a diagnosis of psoriasis. Multivariate Cox regression analysis was performed to estimate the adjusted hazard ratio (aHR) of keratopathy. For the events of keratopathy, 71 patients in the study group and 208 patients in the control group developed keratopathy with a attributable risk of 23.43 per 100,000 person-months (incidence rate ratio = 1.40; P = 0.01) which correlated to the elevated cumulative probability (P = 0.03). The multivariate analysis revealed that the risk of keratopathy was higher in patients who had psoriasis (aHR = 1.31, P = 0.04). In addition, age older than 60 years (aHR = 2.10, P<0.01) and dry eye disease (aHR = 2.79, P<0.01) would also increase the risk of developing keratopathy.
Conclusions: Psoriasis was associated with an increased risk of keratopathy in patients without preexisting prominent corneal disease. Moreover, the risk of incident keratopathy increases with exposure to psoriasis.