Purpose
Pseudoexfoliation syndrome (PEX) is the most common cause of secondary open angle glaucoma, and is associated with an increased risk of lens zonule rupture during cataract surgery. The reported prevalence of PEX varied from 0.2% to 30%. The purpose of current study is to assess the prevalence and associations of PEX in mainland China, where no PEX epidemiological data available yet.
Methods
Beijing Eye Study 2011 is a population-based cross-sectional study. Out of 4403 eligible subjects with an age of 50+ years, 3468 (78.8%) individuals participated (mean age of 64.6+/-9.8 years; range: 50-93 years). All study participants underwent a detailed ophthalmological examination. PEX was assessed by an experienced ophthalmologist using slit-lamp biomicroscopy after pupil dilation.
Results
Participants refusing pupil dilation, with aphakia, pseudophakia, or severe corneal opacities were excluded. Definite pseudoexfoliation was observed in 72/3022 subjects (2.38%, 95% confidence interval (CI):1.84,2.93). Suspected PEX was detected in 104/3022 subjects (3.44%; 95%CI:2.8,4.1). The overall prevalence of PEX (definite and suspected) was 5.82% (95%CI:4.99,6.66). In 80 (45.5%) subjects, PEX was detected bilaterally. PEX prevalence increased from 1.1% in the age group of 50-54 years, to 3.5%, 5.7%, and 11.8% in the age groups of 60-64 years, 70-74 years, and 80+ years, respectively. In multivariate analysis, presence of PEX was significantly associated with older age (P<0.001; odds ratio (OR): 1.08 (95%CI:1.04,1.10)), shorter axial length (P=0.03; OR: 0.82 (95%CI:0.68,0.98)), and shallower anterior chamber (P=0.03; OR: 0.59 (95%CI:0.36,0.95)). PEX was not significantly (all P>0.05) associated with gender, diabetes mellitus, blood pressure, psychological depression, smoking, dyslipidemia, and body mass index; nor with central corneal thickness, corneal diameter, optic nerve head measurements, choroidal thickness, retinal vessel diameters, early age-related macular degeneration and retinal vein occlusion.
Conclusions
In a North Chinese population aged 50+ years, prevalence of definite PEX was 2.38% (95%:1.84,2.93), suspect PEX 3.4% (95%CI:2.8,4.1) and overall PEX 5.82% (95%CI:4.99,6.66). PEX was significantly associated with older age, shorter axial length and shallower anterior chamber. The relationship between PEX and glaucomatous optic neuropathy remained inconclusive.