[The incidence of the secondary failure of sulfonylurea therapy. Epidemiological research].

The proportion of secondarily insulin-dependent diabetics among all insulin-dependent diabetics and the incidence of secondary failures among all those receiving sulphonylurea preparations was determined for a defined region of Berlin (DDR). Among all diabetics receiving insulin, 40% were type I diabetics on primary insulin treatment. But the remaining 60% were secondary failures who had been on diet alone or in combination with oral antidiabetics. Among 3071 diabetics on glibenclamide secondary failures occurred in 5% per year. The ratio of primary to secondary insulin-receiving diabetics, between 1:5 and 1:6, defined the number of new insulin-dependent patients per year. The findings indicate that insulin-receiving diabetics constitute an epidemiologically heterogeneous patient group.