Abstract

Nearly all juvenile-onset diabetics are free of chronic complications when diagnosed and remain free for some years. The longer they have diabetes the greater is the incidence of complications until after 30 years some, particularly retinopathy, are almost universal. Many maturity-onset diabetics already have complications at the time of diagnosis. It has long been debated whether good control of the blood glucose postpones the onset of complications and slows down their rate of progression, or even reverses them. In 1976 the American Diabetic Association regarded the evidence in favour of good control as sufficient to conclude: ‘The data therefore place the burden of proof upon those who maintain that diabetes control is without effect’.¹