Glaucoma ups risk of surface disease

Glaucoma patients are at an increased risk of developing ocular surface disease (OSD) in at least one eye, according to a study published in the August 2008 issue of the Journal of Glaucoma.

Eamon W. Leung, MD of the Doheny Eye Institute, California, US and colleagues conducted a cross sectional study of patients (n=101) aged ≥18 years with open-angle glaucoma or ocular hypertension who had not used cyclosporine, steroids, topical ocular nonsteroidal anti-inflammatory drugs (NSAIDs), or punctal plugs in the three months before the study commenced. No control group was used. Study subjects completed the Ocular Surface Disease Index questionnaire, and the researchers conducted corneal and conjunctival lissamine green staining, tear break-up time and Schirmer tests.

Dry eye symptoms were reported by 59% of patients (n=60); 27% (n=27) had severe symptoms. Decreased tear production in at least one eye was detected in 61% of patients (n=62); this deficiency was classified as "severe" in 35% of eyes (n=35). 22% of patients (n=22) tested positive on the corneal and conjunctival lissamine green staining test. Tear quality was found to be impaired in 78% of eyes (n=79), and severely impaired (in at least one eye) in 65% of patients (n=66). After controlling for accepted variables in multivariate logistic regression analysis, the researchers concluded that subjects increased their risk of producing abnormal lissamine green staining test results by two with every application of eye drops containing benzalkonium chloride (BAK).

The researchers concluded that BAK-containing medications increase the likelihood of OSD and that, therefore, patients with open-angle glaucoma or ocular hypertension are at an increased risk of showing symptoms of OSD.