Relation of Glycemic Control to Diabetic Microvascular Complications in Diabetes Mellitus

doi:10.1059/0003-4819-124-1_Part_2-199601011-00003

Relation of Glycemic Control to Diabetic Microvascular Complications in Diabetes Mellitus

Ronald Klein, MPH, MD;
Barbara E. K. Klein, MPH, MD; and
Scot E. Moss, MA

From the University of Wisconsin Medical School, Madison, Wisconsin. Note: This article is one of a series of articles comprising an Annals of Internal Medicine supplement entitled “Risks and Benefits of Intensive Management in Non-Insulin-dependent Diabetes Mellitus: The Fifth Regenstrief Conference.” To view a complete list of the articles included in this supplement, please view its Table of Contents. Acknowledgments: The authors thank their collaborators, Karen Cruickshanks, PhD; Matthew D. Davis, MD; and Polly Newcomb, PhD, who provided scientific advice; the 452 Wisconsin physicians and their staffs who participated in and supported this study; and Terry Spennetta and Earl Shrago, MD, who provided laboratory support (P30 AM AG 26659, Public Health Service, National Institutes of Health, Bethesda, Maryland). Grant Support: By National Institutes of Health grant EYO-3083 (R Klein, BEK Klein) and, in part, by Research to Prevent Blindness (Dr. Klein, Senior Scientific Investigator Award). Requests for Reprints: Ronald Klein, MD, MPH, Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, 610 North Walnut Street, 460 WARF, Madison, WI 53705-2397. Current Author Addresses: Drs. Klein. Klein, and Moss: Department of Ophthalmology and Visual Sciences. University of Wisconsin-Madison, 610 North Walnut Street, 460 WARF, Madison, WI 53705-2397.

Abstract

Objective: To describe the relation between glycated hemoglobin and the incidence or progression, or both, of diabetic microvascular complications in persons with insulin-dependent (IDDM) and non–insulin-dependent diabetes mellitus (NIDDM).

Design: Population-based cohort study.

Setting: An 11-county area in southern Wisconsin.

Patients: All persons with IDDM diagnosed before age 30 and taking insulin (n = 996) and a probability sample (based on duration of disease) of persons diagnosed with diabetes at age 30 or older who were either taking insulin (n = 674) or not taking insulin (n = 696) and who participated in a baseline examination from 1980 to 1982. Survivors of the cohort were re-examined again in 1984 to 1986 and 1990 to 1992.

Measurements: The incidence and progression of diabetic retinopathy was determined by masked grading of stereoscopic color fundus photographs using the modified Early Treatment Diabetic Retinopathy Study severity scale. Gross proteinuria was determined using a dipstick. Ten-year incidence of renal dialysis or transplantation or loss of tactile sensation or of temperature sensitivity was based on self-reported history.

Results: The glycated hemoglobin level at baseline was strongly related to the incidence or progression, or both, of diabetic retinopathy, the incidence of gross proteinuria, and the incidence of loss of tactile sensation or temperature sensitivity in persons with either IDDM or NIDDM.

Conclusions: These prospective epidemiologic data suggest that glycemic control is similarly related to the incidence and progression of diabetic microvascular complications in both IDDM and NIDDM. However, further evidence from clinical trials in persons with NIDDM is necessary to assess the risks and benefits of such treatment in preventing these complications.