Variations in Trabeculectomy and Glaucoma Drainage Device Use for the Treatment of Glaucoma in the United States

Abstract

Purpose: To estimate geographic variations and surgeon and patient characteristics associated with the use of trabeculectomy and glaucoma drainage devices (GDDs) to treat glaucoma among US Medicare fee-for-service (FFS) beneficiaries.

Design: Observational cohort study of a Medicare claims database.

Participants: US Medicare Part B FFS patients (age ≥65 years) and their glaucoma surgeons.

Methods: Analysis of Limited Data Set claims for the 5% sample from Medicare Provider and Utilization and Payment Data was used to identify trabeculectomy and GDD claims with diagnosis codes for patients treated in the United States from January 1, 2014, to September 30, 2015. The number of patients who underwent trabeculectomy or GDD placement was calculated for each US census region. Regional variations were evaluated with the extremal quotient. Multivariate binomial logistic regression was performed to analyze surgeon (career stage and sex), patient (age, race, sex, and ICD-9-CM diagnosis code), and regional characteristics associated with trabeculectomy and GDD placement.

Main outcome measures: Rates of trabeculectomy and GDD placement performed for Medicare Part B FFS patients by US census region.

Results: From January 1, 2014, to September 30, 2015, the odds that patients received trabeculectomy versus GGD placement varied by region. Patients in the South (odds ratio [OR], 2.14; 95% confidence interval [CI], 1.74-2.66; P < 0.001) and Midwest (OR, 1.42; 95% CI, 1.11-1.83; P < 0.01) were significantly more likely to receive GDD placement than patients in the Northeast. The extremal quotient was 2.16, which confirmed high regional variation. Characteristics associated with increased odds of receiving GDD placement were age greater than 84 years (OR, 1.47; 95% CI, 1.11-1.95), African American race (OR, 1.37; 95% CI, 1.11-1.69), and ICD-9-CM diagnosis of glaucoma associated with vascular disorders (OR, 5.87; 95% CI, 2.78-12.41).

Conclusions: High regional variation in trabeculectomy and GDD placement was observed. Placement of a GDD was more likely to be performed in the South. Placement of a GDD was more likely in African American patients and patients with glaucoma associated with vascular disorders, and was more likely performed by early-career surgeons.