Prospective randomized controlled trial comparing the outcomes and costs of two eyecare adherence interventions in diabetes patients.

Abstract

Diabetic retinopathy is one of the leading causes of vision impairment among adults in the USA. While it is suggested that diabetics receive annual dilated fundus examinations (DFE), many patients do not adhere to these recommendations. This paper investigates the outcomes and costs of an educational and telephone intervention on DFE follow-up adherence in patients with diabetes. In a prospective trial, 356 diabetic patients due for a DFE at an urban eye clinic were randomly assigned to usual care (UC; reference case), mailed intervention (MI), or telephone intervention (TI). UC patients (n=119) received a standard form letter. MI patients (n=117) received a personalized letter encouraging scheduling of an eye examination with an educational brochure about diabetic eye disease. TI patients (n=120) received personal calls (up to three attempts) to schedule a follow-up with standard form letter. The primary outcome was obtaining a DFE within 90days of suggested return. Costs (US$ 2013) included time costs for staff, phone charges, supplies, and postage. Since TI involved greater cost components compared to MI, univariate sensitivity analysis examined the impact of reducing phone costs. Patients were mostly female (66%) and African American (70%) with a mean age of 61years. TI patients were more likely to schedule DFE [65 vs. 42%; relative risk (RR) 1.54; CI 1.20-1.96; P<0.001] versus UC patients. Obtaining a DFE within 90days of suggested return was also significantly higher among TI patients compared to UC patients (51 vs. 36%, RR 1.41; CI 1.05-1.89; P=0.024). MI patients were slightly less likely to schedule DFE versus UC patients (38 vs. 42%, RR 0.90; CI 0.66-1.22; P=NSS) and obtain a DFE (32 vs. 36%; RR 0.90; CI 0.63-1.28; P=NSS). The total cost of TI was US$798.28 or US$6.65/patient and the cost/follow-up DFE was US$26.05. Sensitivity analyses revealed that the cost/follow-up can be greatly reduced but remains greater compared to UC (US$2.76 if US$0.25/call, US$11.13 if $1/call; US$22.29 if US$2/call). Personal phone assistance in scheduling DFE follow-up is more effective but also more costly. Follow-up research has been initiated to determine whether automated phone reminders can achieve similar effectiveness at a lower cost.