Incidence and baseline risk factors for pseudoexfoliation in Sweden: a long-term follow-up study

Abstract

Purpose: To estimate the incidence of pseudoexfoliation (PEX) and its associated risk factors in a defined population in Sweden. Methods: The development of PEX was studied in a cohort of 489 residents aged 65–74 years, examined in a population survey in the municipality of Tierp 1984–1986. To expand the sample size, 576 people were recruited by means of glaucoma case records established at the Eye Department in Tierp in 1978–2007. In this way, the cohort comprised 1065 subjects, representing nearly 10 500 person-years at risk. Incidence rates with 95% confidence intervals (CIs) were calculated. Survival analyses were performed to identify predictors for PEX. Those with a follow-up time shorter than 1 year were excluded. Results: By the end of the study in November 2018, 179 new cases of PEX had been found. Of these, 78 had participated in the population survey, equal to an incidence rate of 14.8 per 1000 person-years (95% CI 11.5–18.1). The development of PEX was associated with higher age (hazard ratio 1.08 per year; 95% CI 1.03–1.13) and female gender (hazard ratio 1.59; 95% CI 1.16–2.18). Conclusion: In this study on a Swedish population, the incidence of PEX was high. Increasing age and female gender were the only predictors for PEX identified.