Association between high concentration of antibodies to insulin and some diseases common in the elderly.

Antibodies to insulin (IA) were measured by graded hemagglutination in 164 patients and in 90 control subjects aged 18-65 years. The greatest prevalence of these antibodies was found in patients with the organic mental syndrome, of whom 70% (n = 110) had an antibody concentration above the normal 95th percentile. Among patients with diabetes, hypertension and cerebrovascular accidents, 42% had a high concentration of IA, while in all other geriatric patients (n = 21) the concentration of these antibodies was within the normal range.