Determinants in Initial Treatment Choice for Diabetic Macular Edema

Abstract [from journal]

Purpose: To assess how patient choices (out-of-pocket costs, insurance plan, geographic region) impact initiation of therapy for diabetic macular edema (DME).

Design: Retrospective cohort study using administrative medical claims data from a large, national insurer.

Participants: All patients newly diagnosed with DME from 2013 through 2016 were observed for 90 days after diagnosis or until first treatment was received.

Methods: Multivariate logistic regression was used to create odds ratios comparing different baseline demographic and patient-related factors.

Main Outcome Measures: The primary outcome was the odds of receiving the different possible initial treatments for DME (anti-vascular endothelial growth factor [VEGF], focal laser treatment, steroids, or observation), no treatment, and not following up.

Results: Of the 6220 newly diagnosed DME patients, 3010 (48.4%) underwent a follow-up examination within 90 days of diagnosis, and of those, 1453 patients (48.3%) received treatment in the observation window, including 614 (20.4%) with bevacizumab, 191 (6.3%) with ranibizumab or aflibercept, 560 (18.6%) with focal laser, 38 (1.3%) with steroid injection, and 50 (1.7%) with an injection of an unspecified drug. Having a copay (vs. $0) lowered the odds of receiving any treatment (odds ratio [OR] = 0.60; 95% confidence interval [CI], 0.51-0.71; P < 0.001) and of receiving each treatment individually (anti-VEGF treatment: OR = 0.72; 95% CI, 0.59-0.88; bevacizumab: OR = 0.73; 95% CI, 0.59-0.91; ranibizumab or aflibercept: OR, 0.70; 95% CI, 0.49-0.99; focal laser: OR = 0.44; 95% CI, 0.35-0.55; P < 0.001). Contrary to having a copay, having a high deductible and type of insurance plan were not associated with initiating treatment (P > 0.41 for all comparisons). Patients in the Northeast showed lower odds of initiating anti-VEGF treatment (OR = 0.60; 95%CI, 0.44-0.82; P < 0.001) and specifically bevacizumab (OR = 0.47; 95% CI, 0.33-0.67; P < 0.001). Furthermore, Northeast patients who were treated with anti-VEGF showed a higher odds of receiving ranibizumab or aflibercept compared with bevacizumab (OR = 2.39; 95% CI, 1.31-4.37; P < 0.001). Southern Midwest patients showed a higher odds of treatment (anti-VEGF: OR = 1.35; 95%CI, 1.02-1.77; P < 0.001; bevacizumab: OR = 1.40; 95% CI, 1.04-1.87; focal laser: OR = 1.39; 95% CI, 1.01-1.89; P < 0.001).

Conclusions: Patient choices such as copays and where they live are important factors in determining the initial choice of treatment for DME.