Stable and brittle diabetes

1. 1. A classification of diabetes, based on the study of 172 patients, is presented. An attempt is made to separate persons with stable diabetes from those with brittle diabetes, and to express diabetic control in these patients. 2. 2. The incidence of degenerative complications was higher in patients with stable diabetes than in those with brittle diabetes. 3. 3. The incidence of severe diabetic retinopathy (grades III and IV) in adult patients with brittle diabetes with long-standing diabetes was very low. 4. 4. Patients with stable diabetes with poor control showed a significantly higher incidence of late degenerative complications than patients with stable diabetes with good control. 5. 5. Further indications are presented to support the concept, already described in the literature, that there are two types of diabetes mellitus which should be looked upon as distinct metabolic entities.