Fifteen Year Followup of the Ocular and Medical Status of Early Treatment Diabetic Retinopathy Study (ETDRS) Patients Enrolled at the Joslin Diabetes Center

PURPOSE:

To evaluate the ocular & medical status of patients enrolled in the ETDRS at the Beetham Eye Institute (BEI) of the Joslin Diabetes Center 15 years after the conclusions of the landmark clinical trial.

METHODS:

ETDRS was a multicenter clinical trial that evaluated laser photocoagulation (PC) in patients with diabetic retinopathy. The current investigation is a single–site, observational, followup study. Patients alive in 2004 were contacted by mail & telephone and respondents received complete eye exam at the BEI, including ETDRS protocol refraction, VA assessment, and 7–field fundus photography. Present health status, diabetes control & medical complications were obtained by standardized questionnaire. Blood pressure, HbA1c, lipid profile & urinalysis were obtained within 3mo of ocular exam.

RESULTS:

The BEI was the highest enrolling center in the ETDRS accounting for 7% of all patients studied. Of the 232 patients alive at ETDRS conclusion, 94 (41%) were confirmed deceased, 89 (38%) did not respond and 49 (21%) were re–examined as of November 2004 which was 12–17yrs after their final ETDRS visit (median=15yrs). BEI–enrolled patients had mostly type 1 diabetes with 88% evaluated being type 1 vs ∼30% overall in ETDRS. On exam, 9.8% of eyes had > 20/20 VA, 36% > 20/20, 85% > 20/40, 91% > 20/63, 94% > 20/80 and 97% > 20/200. As compared with ETDRS final exam, 16% of eyes had moderate vision loss (>3 lines). Two eyes had severe vision loss (< 5/200, total RD & macular scar). No patient had VA < 20/40 binocularly. All untreated eyes with severe NPDR at conclusions of ETDRS had received scatter PC by the time of followup exam. Post–ETDRS scatter and/or focal PC was performed in 33% of eyes, cataract surgery in 33% and pars plana vitrectomy in 13%. At followup, average SBP & DBP was 131 & 68 mmHg respectively, median HbA1c was 7.8%, and 29% had concurrent nephropathy, neuropathy & cardiovascular disease. Recruitment and assessment of remaining survivors continues.

CONCLUSIONS:

As previously reported for a group of mostly type 2 diabetes in the ETDRS, mortality rate of this primarily type 1 cohort was high. Concurrent complications were frequent; however, there was long–term maintenance of good VA. Additional PC & cataract extraction was common, suggesting both the benefit and the need for life–long ophthalmic evaluation in patients with diabetic retinopathy.