The Wisconsin epidemiologic study of diabetic retinopathy. VI: Retinal photocoagulation

The Wisconsin Epidemiologic Study of Diabetic Retinopathy: XVII. The 14-year incidence and progression of diabetic retinopathy and associated risk factors in type 1 diabetes

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140673697062090.pdf

Effect of lisinopril on progression of retinopathy in normotensive people with type 1 diabetes

Ten-year Incidence of Visual Loss in a Diabetic Population

Objective: To examine the 10-year incidence and progression of diabetic retinopathy. Design: Population-based incidence study. Participants: Seven hundred sixty-five insulin-taking diabetic persons diagnosed before age 30 years, 251 insulin-taking diabetic persons diagnosed at age 30 years or older, and 282 non-insulin-taking diabetic persons diagnosed at age 30 years or older who participated in baseline, 4-year, and 10-year follow-up examinations. Main Outcome Measures: The 10-year incidence of any retinopathy, progression of retinopathy, and progression to proliferative retinopathy were detected by masked grading of stereoscopic color fundus photographs using the modified Airlie House classification and the Early Treatment Diabetic Retinopathy Study severity scheme. Results: The 10-year incidence of retinopathy (89%, 79%, and 67%), progression of retinopathy (76%, 69%, and 53%), and progression to proliferative retinopathy (30%, 24%, and 10%) were highest in the group diagnosed before age 30 years, intermediate in the insulin-taking group diagnosed at age 30 years or older, and lowest in the non-insulin-taking group, respectively. Increased risk of proliferative retinopathy was associated with more severe retinopathy at baseline. Conclusions: These data suggest relatively high 10-year rates of incidence and progression of retinopathy, and despite changes in the treatment of diabetes, there has been little change in the incidence and progression of diabetic retinopathy during the 10-year study period.

The Wisconsin Epidemiologic Study of diabetic retinopathy. XIV. Ten-year incidence and progression of diabetic retinopathy.

Among the 1135 Rochester residents discovered to have diabetes in the period 1945–69, the prevalence of retinopathy was 2.6% at the time of initial diagnosis. Among those free of retinopathy at diagnosis of diabetes, the subsequent incidence of any retinopathy was 17.4 per 1000 person-years and for proliferative retinopathy alone was 1.6 per 1000 person-years, based on 12,000 person-years of follow-up. The incidence rate of retinopathy was almost three times greater among residents with insulin-dependent (IDDM) than with non-insulin-dependent diabetes (NIDDM); however, the actual number of retinopathy cases was over four times greater among the more numerous residents with NIDDM. By 20 yr after diagnosis of diabetes, the cumulative incidence of retinopathy approached 70% among IDDM subjects and was 30% and 36%, respectively, among the obese and nonobese NIDDM residents. The epidemiologic patterns for proliferative retinopathy were qualitatively similar to those for nonproliferative retinopathy. The risk of blindness was greater among those with proliferative than with nonproliferative retinopathy but was substantial even for those without retinopathy. Most blindness was caused by factors other than isolated diabetic retinopathy.

Incidence of diabetic retinopathy and blindness: a population-based study in Rochester, Minnesota.

Retinopathy is an important sequela of diabetes mellitus, but clinical risk factors for this condition have rarely been assessed in a geographically defined population. In this population-based study, the 1135 Rochester, Minnesota, residents with diabetes mellitus initially diagnosed between 1945 and 1969 (incidence cohort) were followed through their complete medical records in the community to January 1, 1982. Because most of the cases of diabetic retinopathy in Rochester residents developed in patients with non-insulin-dependent diabetes mellitus (NIDDM), risk factors for diabetic retinopathy were examined in this group (N = 1031). A proportional hazards model identified the following risk factors for diabetic retinopathy in NIDDM: elevated initial fasting blood glucose level, marked obesity, and earlier age at onset of diabetes. Stratified analyses indicated that duration of diabetes was also significantly associated with an increased risk of retinopathy. Two secular trends, increasing detection of "mild" NIDDM and decreasing risk of diabetic retinopathy, had a major effect on retinopathy risk assessment. These data also suggest that insulin therapy is not an independent risk factor for diabetic retinopathy.

M. S. Dwyer

Papers

Incidence of diabetic retinopathy and blindness: a population-based study in Rochester, Minnesota.

Risk factors for diabetic retinopathy: a population-based study in Rochester, Minnesota.