Factors associated with lifetime risk of open-angle glaucoma blindness

Abstract

Purpose: To investigate factors associated with bilateral glaucoma blindness, particularly factors available at the time of diagnosis.

Methods: Retrospective chart review of all patients with primary open-angle glaucoma (POAG) or pseudoexfoliative glaucoma (PEXG) followed at the Department of Ophthalmology or Low Vision Center of Skåne University Hospital, Malmö, Sweden, who died between January 2006 and June 2010. Disease stage at diagnosis was defined by a simplified version of Mills' glaucoma staging system using perimetric mean deviation (MD) to define six stages of severity. Blindness was defined according to WHO criteria. We used logistic regression analysis to examine the association between risk factors and glaucoma blindness.

Results: Four hundred and 23 patients were included; 60% POAG and 40% PEXG. Sixty-four patients (15%) became blind from glaucoma. Blind patients had significantly longer mean duration with diagnosed disease than patients who did not go blind (14.8 years ± 5.8 versus 10.6 years ± 6.5, p < 0.001). The risk of blindness increased with higher intraocular pressure (IOP) (OR 1.08, 95% CI 1.03-1.13) and with each stage of more advanced field loss at time of diagnosis (OR 1.80 95% CI 1.34-2.41). Older age at death was also associated with an increased risk of blindness (OR 1.09 95% CI 1.03-1.14), while age at diagnosis was unimportant. PEXG was not an independent risk factor for blindness.

Conclusions: Higher IOP and worse visual field status at baseline were important risk factors, as was older age at death.

Keywords: age; blindness; disease stage; intraocular pressure; open-angle glaucoma; risk factors.