PURPOSE: To report on the prevalence of pseudoexfoliation (PEX) and its association with ophthalmic characteristics and systemic diseases in a well-defined population.METHODS: The Thessaloniki Eye study is a cross-sectional population-based study of chronic eye diseases in Thessaloniki, Greece. Participants with PEX were identified by clinical examination and were compared with those without PEX with regards to ophthalmic characteristics and systemic diseases, after adjusting for age and sex.RESULTS: PEX was found in 11.9% of the 2261 clinic-visit participants. Participants with PEX, compared with those without, had higher intraocular pressure, larger vertical cup-to-disc ratio, and higher percentage with vertical cup-to-disc ratio asymmetry and optic disc damage. The proportion with glaucoma among pseudoexfoliative participants (15.2%) was higher than that for glaucoma among nonpseudoexfoliative participants (4.7%). After excluding glaucoma participants, the only difference was the 0.6 mm Hg higher intraocular pressure in participants with PEX. Compared with nonpseudoexfoliative eyes, the presence of PEX on iris only or on both iris and lens was associated with higher intraocular pressure, whereas the presence of PEX on lens only was not. PEX was not associated with any systemic disease.CONCLUSIONS: The prevalence of PEX in Greece is relatively high compared with other white populations. PEX was associated with higher intraocular pressure and higher percentage with optic disc damage, secondary to the higher proportion with glaucoma among pseudoexfoliative participants than among nonpseudoexfoliative participants. In nonglaucoma participants, eyes with PEX had only slightly higher intraocular pressure, but this was not observed in eyes with PEX on lens only.