High prevalence of ocular surface disease identified in glaucoma patients

A cross-sectional study has found that many patients with open-angle glaucoma or ocular hypertension also have symptoms of concurrent ocular surface disease in at least one eye. In addition, using medications containing benzalkonium chloride may affect vision-related quality of life in these patients.

Eamon W. Leung, MD, and colleagues evaluated the prevalence of ocular surface disease in 101 patients who were aged 18 years or older and had either open-angle glaucoma or ocular hypertension. These patients had not used cyclosporine, steroids, topical NSAIDs or punctal plugs within 3 months of baseline. The study results are published in the August issue of Journal of Glaucoma.

All patients completed an Ocular Surface Disease Index questionnaire and underwent Schirmer testing, corneal and conjunctival lissamine green staining, and tear break-up time evaluation.

According to questionnaire responses, 60 patients (59%) reported dry eye symptoms in at least one eye, and 27 patients (27%) reported severe dry eye symptoms.

Schirmer testing revealed that 62 patients (61%) experienced reduced tear production in at least one eye; in addition, 35 patients (35%) had severe tear deficiency.

Twenty-two patients (22%) showed positive corneal and conjunctival lissamine green staining results, although no patients had severe staining, the authors reported.

According to tear break-up time testing, 79 patients (78%) showed abnormal tear quality, and 66 patients (65%) had a severe decrease in tear quality in at least one eye.

After adjusting for age and sex, multivariate logistic regression analysis showed that each eye drop containing benzalkonium chloride increased the odds of having abnormal lissamine green staining test results by approximately two times (P = .034), according to the study.

However, because many patients were already taking topical medications at baseline and used different types of medications for varying periods of time during the study, the authors said that "any attempt to correlate the types of medications and duration of therapy with signs and symptoms of [ocular surface disease] would likely be inappropriate in this sample."