An Assessment of the Prevalence of Cannabis Use in Eye-Clinic Patients and its Implications in Glaucoma
Purpose: To assess the prevalence of cannabis use among ophthalmic patients, considering its effect on lowering intraocular pressure which is used in the diagnosis of glaucoma. Design: A cross-sectional prevalence survey study.
Methods: A survey was conducted over a 5-month span starting in October 2022 in four different eye clinics, at the University of Minnesota (UMN) Phillips Wangensteen Building. The first part of the survey assessed demographic information (e.g., ethnicity, income, education level, marital status). The second part of the survey assessed current knowledge about marijuana use in glaucoma, marijuana use in family and friends, and about past and current usage of marijuana. The final part of the survey was adapted from Belyea et al. who developed a questionnaire to evaluate patient perceptions of marijuana and glaucoma, as well as predicting intentions to use marijuana for glaucoma.
Results: Among study patients, 12.8% reported using marijuana recently (< 1 month from survey administration), 7.4% described themselves as regular users, and 4.3% of patients reported using it every day. We also found that while 52.2% of patients were interested in using marijuana for their glaucoma, 71.4% of patients were not sure if it was an effective treatment for glaucoma. More non-glaucoma patients used marijuana recently than glaucoma patients (30% vs. 8.1%, p = 0.00158). Patients reported to not be interested in using marijuana if it is less effective than conventional glaucoma therapies (70.8% disagree). There was a relationship between agreement that marijuana was harmful to physical health and decreased intention to use marijuana for glaucoma (p = 0.01).
Conclusion: These findings indicate a need for increased screening for recent marijuana use to ensure more accurate diagnosis and prevent misdiagnosis from inaccurate IOP measurements.