The Long-term Effects of Laser Photocoagulation Treatment in Patients with Diabetic Retinopathy The Early Treatment Diabetic Retinopathy Follow-up Study Emily Y. Chew, MD, 1 Frederick L. Ferris III, MD, 1 Karl G. Csaky, MD, PhD, 2 Robert P. Murphy, MD, 1 Elvira Agro ´n, MSc, 1 Darby J. S. Thompson, MSc, 3 George F. Reed, PhD, 1 Andrew P. Schachat, MD 4 Objectives: To evaluate the long-term natural history and effects of laser photocoagulation treatment in patients with diabetic retinopathy. Design: Follow-up study of the 214 surviving patients enrolled originally at the Johns Hopkins Clinical Center for the Early Treatment Diabetic Retinopathy Study (ETDRS), which was a clinical trial designed to evaluate the role of laser photocoagulation and aspirin treatment in patients with diabetic retinopathy. Methods: Early Treatment Diabetic Retinopathy Study patients enrolled in the Johns Hopkins Clinical Center had complete eye examinations, including best-corrected visual acuity measurements, fundus photographs, and medical questionnaires throughout the 7-year study. They had the same examinations at the final long-term follow-up visit at the National Eye Institute, National Institutes of Health, 13 to 19.5 years after the initial laser photocoagulation (median, 16.7 years). Main Outcome Measures: The major outcomes were mortality and the rates of moderate and severe vision loss. The secondary outcomes were progression of diabetic retinopathy and need for other eye surgery. Results: Of the 214 patients who were alive at the end of the original ETDRS in 1989, 130 (61%) were deceased at the time of the re-examination. Of the 84 who were alive, 71 (85%) were examined at their long-term follow-up visit at the National Institutes of Health. At the long-term follow-up examination, 42% had visual acuity of 20/20 or better, and 84% had visual acuity of 20/40 or better in the better eye. Compared with baseline, 20% of patients had moderate vision loss (loss of 3 lines or more vision) in the better eye at follow-up. Only one patient had visual acuity of 20/200 bilaterally. He had visual acuity loss secondary to age-related macular degeneration. No patient had severe vision loss (worse than 5/200). All the initially untreated eyes of patients who had severe nonproliferative diabetic retinopathy or worse by the time of the ETDRS closeout visit of the original study received scatter photocoagulation treatment. Focal photocoagulation was performed in 43% bilaterally and 22% unilaterally. Cataract surgery was performed in 31% of the patients, vitrectomy in 17%, and glaucoma surgery in one patient. Conclusions: As previously reported, the mortality rate of patients with diabetic retinopathy is much higher than that of the general population. For those who survived, aggressive follow-up, with treatment when indicated, seems to be associated with maintenance of good long-term visual acuity for most patients. The need for laser scatter photocoagulation with long-term follow-up seems to be high. Ophthalmology 2003;110:1683–1689 © 2003 by the American Academy of Ophthalmology. Diabetic retinopathy is a leading cause of vision impairment in the adult population in the United States. 1 The treatment strategies for diabetic retinopathy developed over the last several decades are, in part, based on National Institutes of Health–supported clinical trials evaluating diabetes control, Originally received: August 21, 2002. Accepted: February 19, 2003. Manuscript no. 220573. 1 National Eye Institute/National Institutes of Health, Division of Epide- miology and Clinical Research, Bethesda, Maryland. 2 National Eye Institute/National Institutes of Health, Laboratory of Im- munology, Bethesda, Maryland. 3 EMMES Corporation, Rockville, Maryland. 4 Wilmer Eye Institute, Johns Hopkins Medical Institutions, Baltimore, Maryland. Reprint requests to Emily Y. Chew, MD, Division of Biometry and Epidemiology, National Eye Institute/National Institutes of Health, Build- ing 31, Room 6A52, 31 Center Drive, MSC-2510, Bethesda, MD 20892- 2510. 1683 © 2003 by the American Academy of Ophthalmology ISSN 0161-6420/03/$–see front matter Published by Elsevier Inc. doi:10.1016/S0161-6420(03)00579-7