Abstract
Purpose:
We aim to characterize the association between adherence to glaucoma medication and progression of visual fields in patients at the Baltimore Veteran Affairs hospital. Here we present preliminary data on medication adherence and the impact of medical comorbidities in treatment compliance.
Methods:
Patients who were treated at the Baltimore Veterans Affairs Hospital in the Eye Clinic with a diagnosis of glaucoma, ≥3 Humphrey Visual Field examinations, and have been prescribed topical glaucoma therapy within 1/1/2002-12/31/2011. Chart review was performed using the Computerized Patient Record System. Mean possession ratio (MPR) was used to assess medication adherence and was calculated using total days of medication possessed by the patient divided by total days needed.
Results:
A total of 200 patients were included in the study with an average MPR of 1.06 ± 0.397, median 1.06. The study population was 99% male, with 59.5% African American, 33.5% Caucasian, 6.5% other or unknown. No statistical significance was observed in average MPR between African American and Caucasian patients (p= 0.17). The most prevalent medical comorbidity within the study population was hypertension (0.83), followed by hyperlipidemia (0.63), diabetes (0.44), arthritis (0.29), substance abuse (0.235), mood disorders (0.17), obesity (0.155), hearing loss (0.15), dementia (0.115), and obstructive sleep apnea (0.09). Using a paired t-test analysis, no significant difference in average MPR was identified among the listed subgroups.
Conclusions:
This study aimed to investigate glaucoma medication adherence in 200 patients at the Veteran Affairs Hospital in Baltimore, Maryland. The average MPR in our patient population (1.06) is higher than those reported in similar studies across the United States. Despite the widely reported association between African American race and decreased adherence to glaucoma medication, this was not reflected in our data. Furthermore, we did not find any predictors of decreased adherence to medications across the specified medical and psychological co-morbidities. These findings may be due to our method of patient selection which required the completion of at least 3 visual field tests and may present an inherent bias towards greater compliance. These data represent a subset of results from a larger study which aims to investigate the association between glaucoma medication adherence and visual field progression.