Abstract
Purpose :
The complex interaction between diabetes, hyperglycemia, insulin treatment and glaucoma remains incompletely understood, and is particularly relevant given insulin has recently emerged as a potential therapeutic target in glaucomatous degeneration. We aimed to investigate outcomes of primary open-angle glaucoma (POAG) patients with and without type 2 diabetes mellitus (T2DM) on either oral hypoglycemic agents or insulin.
Methods :
Retrospective observational study using U.S nationwide healthcare insurance claims database. Patients aged ≥40 years old with a diagnosis of POAG were included. A diagnosis of T2DM and use of either oral hypoglycemic agents or insulin therapy were the primary predictors. The main outcome measure was time to first glaucoma surgery. Multivariable Cox proportional hazards regression models evaluated factors associated with POAG progression requiring surgery. Insulin use was analyzed as a time-varying co-variate with the date of first fill considered the start date.
Results :
A total of 829,562 POAG patients were included for analysis, of which 212,164 (25.6%) had T2DM. Mean age was 68.7 years (SD 10.7) and 57% were female. There were 211,055 patients taking oral hypoglycemic agents, while 82,413 were on insulin. While T2DM was a significant predictor of progression to glaucoma surgery in univariate analyses (HR 3.50, 95%CI 3.43-3.57, p<0.001), this was no longer significant once adjusted for HbA1c, demographic (age, gender, socioeconomic status, race) and glaucoma factors (severity, baseline medications, previous laser trabeculoplasty). When evaluating only POAG patients with T2DM, compared to patients only taking oral hypoglycemic agents, we found that insulin use was associated with a 1.11 higher hazard of requiring glaucoma surgery (95%CI 1.07-1.15, p<0.001), and remained an independent predictor in multivariate analyses after adjusting for confounders (HR 1.08, 95%CI 1.04-1.13, p<0.001).
Conclusions :
Insulin use amongst POAG patients with T2DM may be associated with a higher rate of progression requiring glaucoma surgery. Additional studies are required to better characterize this relationship.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.