2011 HSR&D National Meeting Abstract
1030 — Substance Use Disorder and the Risk of Open-Angle Glaucoma
French DD (Indianapolis VAMC), Margo CE
(Tampa VAMC), Harman LE
To test the hypothesis that cocaine use (abuse and/or dependency) is associated with open-angle glaucoma.
A case-control study. Potential case patients were identified from the Veterans Health Administration (VHA) national clinical database using International Classification of Disease, Version 9, Clinical Modification (ICD-9-CM) for open-angle glaucoma for fiscal year 2009. Inclusion criteria included consecutive prescriptions for one or more topical anti-glaucoma medications. Cocaine exposure was identified through ICD-9-CM codes. The odds of cocaine exposure were compared to the overall outpatient population of national VHA beneficiaries and adjusted for age and other illicit drug use. A nested case-control study was conducted to examine the confounding influence of race.
Age adjusted odds ratios of cocaine exposure among patients with glaucoma were statistically significant for both men (3.52 [95%CI: 3.21-3.86]) and women (1.87 [95%CI 1.79-1.96]), and did not change significantly when analyzed according to drug dependency status. Subset analysis adjusted for age, other illicit drugs, and race remained significant for men (1.45 [95%CI 1.27-1.66]), but not women. Persons with substance use disorder and glaucoma were nearly 18 years younger than glaucoma patients without a drug exposure history.
This pilot study suggests the use of cocaine and possibly other illicit drugs are predictive of glaucoma. Should the association of substance use disorder (cocaine or cocaine/poly drug abuse) and open-angle glaucoma be verified, it represents a potentially modifiable risk factor for vision loss.
Cocaine exposure alone points to a biological pathway, where substance use disorder speaks in favor of a behavioral mechanism. The observation that glaucoma in drug-exposed patients is diagnosed 18 years before it is detected in non-exposed patients is easier to understand in terms of a biological predisposition rather than a bias towards early diagnosis.The association of illicit drug use with open-angle glaucoma requires confirmation, but if the relationship is real, it could lead to new strategies to prevent vision loss.