Four-year analysis of diabetic retinopathy rates using teleretinal screening shows declining retinopathy rates over time in Central Texas

Abstract

Purpose : Year over year trending of diabetic retinopathy (DR) rates using teleretinal screening in the US remains minimally reported. We analyzed the trajectory of DR rates based on teleretinal images captured at primary care clinics in Central Texas over a 4-year period.

Methods : 19,894 retinal image screenings of diabetic patients were reviewed by retina specialists to identify pathology. A retrospective analysis of DR rates captured by cameras across 12 Central Texas primary care clinics with 2-4 years of data obtained from Intelligent Retinal Imaging Systems (IRIS) cloud-based system was completed. Total consecutive yearly data was aggregated and rates of DR were compared from first to fourth year of screening using pairwise z-test for independent proportions with Holm adjustment of p-value for multiple comparisons.

Results : Aggregated yearly data comparison showed a statistically significant decline in DR rates from the first year of screening (22.56%, 1190/5275) to the fourth year (16.82%, 304/1807) with p < 0.00001. Statistically significant declines with p < 0.05 were also seen comparing the first to second year (20.63%, 1467/7112) and third year (20.18%, 1150/5700) and comparing second and third years to fourth year (Figure 1). There was a decline in DR rate from the first year of screening in 11 out of 12 clinics, displayed in Table 1. Clinics with 4-year data show majority of decrease in DR rate occurring from the first (22.34%) to third (16.93%) year of screening. During this time, 65% of those requiring referral followed up with a retina specialist (Wong RW, et al. IOVS 2017;58:ARVO E-Abstract 2901).

Conclusions : There is a statistically significant decline in rates of detected diabetic retinopathy over four years of teleretinal screening. This suggests sustained use of teleretinal screening and subsequent referral to ophthalmologists may reduce the number of unscreened diabetic patients and increase necessary referral of diabetic patients with DR in the population over time. Continued use of teleretinal screening programs may show if this declining trend eventually stabilizes.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.

 

Fig. 1. Aggregated diabetic retinopathy screenings and corresponding rate by year of camera usage

 

Table 1. Clinic screening diabetic retinopathy rates