Abstract
Purpose :
To compare healthcare utilization and visual field progression of glaucoma patients who add or switch topical therapies vs. patients managed on topical monotherapy.
Methods :
This was a retrospective analysis of Kaiser Permanente Southern California electronic health records between 2001 and 2011, with supplemental chart review. Records of newly-diagnosed glaucoma (ICD-9 365.xx) patients aged 18 years or older and prescribed a glaucoma agent within 90 days of diagnosis were included. Two cohorts were defined: patients treated with topical monotherapy for the study duration, and patients who switched or added drugs at any time during follow-up. Outcomes of interest included health care utilization measured by office visits, visual field testing, laser procedures, and surgery. The risk of visual field progression was assessed using multivariable Cox regression.
Results :
6,014 newly diagnosed glaucoma patients were included for analyses; 1,783 remained on monotherapy and 4,231 switched/added medications. Mean follow-up was 8.2 years (SD=2.4). At baseline, 46.9% took beta-blockers, 35.0% prostaglandins, 16.2% adrenergic agents, and 1.4% carbonic anhydrase inhibitors. At 5 years, a greater proportion of patients who added or switched therapy had progressed compared to patients continuing on monotherapy (48.3% vs. 32.8%, p<0.001). Patients who switched/added therapy also had more office visits (20.4 vs. 15.8), more visual field tests (4.9 vs. 4.6) and higher prevalence of trabeculectomies (2.9% vs. 0%) (p<0.001 for all). In multivariable hazard models, predictors of progression from baseline included older age, Black or Hispanic vs. White race/ethnicity, and diabetes; switching or adding therapy was not a statistically significant predictor of progression (HR with 95% CI: 1.10 (1.00, 1.22)).
Conclusions :
Patients who switched or added medications had a larger healthcare burden. They had more office visits and procedures at 5 years from diagnosis, including a significantly higher number of procedures and visual field tests. Thus, this analysis supports the use of the most effective therapeutic option early. Using factors evaluated in the multivariable model, identifying glaucoma patients at higher risk of progression may be possible.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.