Two prospective studies reported in 1993 provided an answer to a controversial question: Would intensive treatment of patients with insulin-dependent diabetes mellitus (IDDM) reduce the development or progression of microvascular complications? The Stockholm Diabetes Study,1 which began in 1982, involved 102 patients (mean age, 30 years; mean duration of diabetes, 17 years) who were followed up for 7.5 years. The Diabetes Control and Complications Trial (DCCT),2 sponsored by the National Institutes of Health, Bethesda, Md, and conducted at 29 centers in the United States and Canada, involved 1441 patients in two cohorts: a primary prevention group (patients without apparent microvascular complications at entry; mean age, 27 years; mean duration of diabetes, 2.6 years) and a secondary intervention group (patients with mild retinopathy at entry; mean age, 27 years; mean duration of diabetes, 8.7 years); the patients in the DCCT were followed up for an average of 6.5 years.
Watts NB, Blevins LS. Endocrinology. JAMA. 1994;271(21):1666-1668. doi:10.1001/jama.1994.03510450038021