Similarities and Differences in Risk Factors for Primary Open-Angle Glaucoma and Pseudoexfoliative Glaucoma in the Thessaloniki Eye Study

Abstract

Purpose: : To investigate risk factors associated with primary open-angle glaucoma (POAG) and pseudoexfoliative glaucoma (PEXG) in the Thessaloniki Eye Study (TES).

Methods: : TES is a cross sectional population-based study of chronic eye diseases in subjects ≥60 years of age in Thessaloniki, Greece. Subjects with POAG, PEXG or pseudoexfoliation (PEX) were identified according to specific criteria. Subjects with POAG were compared to non-PEX controls and subjects with PEXG were compared to PEX-controls regarding demographic, lifestyle, ophthalmic and systemic risk factors. All risk factors with p<0.2 in the univariate analysis were entered into the regression model.

Results: : In regression model, POAG was associated with age (Odds ratio (OR):1.05 per year, p=0.006), IOP (OR:1.14 per mmHg, p<0.001) and coronary artery bypass or vascular surgery (OR:2.04, p=0.012). POAG was also associated with borderline significance with the presence of mild myopia (>-1D and <-3D) (OR:1.97, p=0.063), moderate myopia (≥-3D) (OR:2.16, p=0.078), history of diabetes treated with insulin (OR:2.68, p=0.054) and the presence of normal blood pressure (BP) values (systolic BP <140mmHg and diastolic BP <90mmHg) secondary to antihypertensive treatment compared to no-hypertension (OR:1.99, p=0.096). The presence of high systolic or diastolic BP was not associated with POAG. PEXG was associated significantly with IOP (OR:1.25 per mmHg, p<0.001) and with borderline significance with moderate myopia (OR:2.97, p=0.060).

Conclusions: : In TES, IOP and moderate myopia were the only risk factors associated with both POAG and PEXG. Vascular systemic diseases and their treatment were associated only with POAG, suggesting different pathogenesis between the two common types of open-angle glaucoma.

Keywords: clinical (human) or epidemiologic studies: risk factor assessment