Pseudoexfoliation syndrome and relating factors in a rural Japanese population: the Kumejima Study

Abstract

Purpose: To report the prevalence of pseudoexfoliation (PEX) syndrome and glaucoma associated with PEX (PEX-G) and their relating factors of them in a south-western island of Japan. Methods: A population-based survey of all residents aged ≥ 40 years was conducted in Kumejima, Okinawa, Japan, and 3762 subjects (participation rate, 81.2%) underwent detailed ophthalmic examinations. Presence of PEX material on the lens capsule, iris surface and/or pupillary margin was determined by slit-lamp biomicroscopy. Glaucoma was diagnosed according to the criteria of the International Society of Geographical and Epidemiological Ophthalmology. Results: In subjects aged ≥ 40 years, prevalence rates of PEX syndrome, PEX without glaucoma and PEX-G in at least one eye were 1.5% (95% confidence interval [CI]: 1.0–1.9%), 1.3% (95% CI: 0.9–1.7%) and 0.1% (95% CI: 0.0–0.2%), respectively, excluding eyes after cataract surgery; and 2.8% (95% CI: 2.3–3.3%), 2.2% (95% CI: 1.8–2.6 %) and 0.4% (95% CI: 0.2–0.6%), respectively, including eyes after cataract surgery. Cataract surgery had been performed in 61% of subjects with PEX in at least one eye; presence of PEX showed no significant effects on the intraocular pressure (IOP). A multivariate analysis showed that PEX was associated with older age (p < 0.0001, odds ratio: 1.10 [95% CI: 1.07–1.13]) and working outdoors (p = 0.0395, odds ratio: 2.18 [95% CI: 0.99–4.82]). Conclusions: The prevalence rates of PEX syndrome and PEX-G in a south-western island of Japan were reported. PEX showed no significant effect on IOP, and age and working outdoors were significantly related with PEX.