Long-term Comparative Effectiveness of Telemedicine in Providing Diabetic Retinopathy Screening Examinations: A Randomized Clinical Trial

Abstract

Importance: Minimal information exists regarding the long-term comparative effectiveness of telemedicine to provide diabetic retinopathy screening examinations.

Objective: To compare telemedicine to traditional eye examinations in their ability to provide diabetic retinopathy screening examinations.

Design, setting, and participants: From August 1, 2006, through September 31, 2009, 567 participants with diabetes were randomized and followed up to 5 years of follow-up (last date of patient follow-up occurred on August 6, 2012) as part of a multicenter randomized clinical trial with an intent to treat analysis. We assigned participants to telemedicine with a nonmydriatic camera in a primary care medical clinic (n = 296) or traditional surveillance with an eye care professional (n = 271). Two years after enrollment, we offered telemedicine to all participants.

Main outcomes and measures: Percentage of participants receiving annual diabetic retinopathy screening examinations, percentage of eyes with worsening diabetic retinopathy during the follow-up period using a validated scale from stage 0 (none) to stage 4 (proliferative diabetic retinopathy), and percentage of telemedicine participants who would require referral to an eye care professional for follow-up care using a cutoff of moderate diabetic retinopathy or worse, the presence of macular edema, or an unable-to-determine result for retinopathy or macular edema.

Results: The telemedicine group was more likely to receive a diabetic retinopathy screening examination when compared with the traditional surveillance group during the 6-month or less (94.6% [280/296] vs 43.9% [119/271]; 95% CI, 46.6%-54.8%; P < .001) and greater than 6-month through 18-month (53.0% [157/296] vs 33.2% [90/271]; 95% CI, 16.5%-23.1%; P < .001) time bins. After we offered telemedicine to both groups, we could not identify a difference between the groups in the percentage of diabetic retinopathy screening examinations. Diabetic retinopathy worsened by 2 stages or more in 35 (8.6%) of 409 participants (95% CI, 5.8%-11.2%) and improved by 2 stages or more in 5 (1.2%) of 409 participants (95% CI, 0.1%-2.3%) during the 4-year period. The percent of telemedicine participants requiring referral ranged from 19.2% (52/271) to 27.9% (58/208).

Conclusions and relevance: Telemedicine increased the percentage of diabetic retinopathy screening examinations, most participants did not require referral to an eye care professional, and diabetic retinopathy levels were generally stable during the study period. This finding suggests that primary care clinics can use telemedicine to screen for diabetic retinopathy and monitor for disease worsening over a long period.

Trial registration: clinicaltrials.gov Identifier: NCT01364129.

Figure 1

Flowchart of the Study Protocol

Figure 2

Percent of individuals that received a diabetic retinopathy screening exam (<6 month through >42 month to 54 month time bin) compared by original group assignment (telemedicine, traditional) with type of exam (telemedicine, traditional, or both exams) noted.