Epidemiology of insulin-treated diabetes mellitus in the East-German population: differences in long-term trends between incidence and prevalence rates.

In order to evaluate temporal trend variations of incidence and prevalence rates of Type 1 (insulin-treated) diabetes mellitus in the East-German population (19.6 million) 85,904 incidence cases, recorded by the Diabetes Registry between 1960 and 1989, were analyzed by calculating the regression coefficients for defined time intervals. The total incidence trend was characterized by a rise from 18/10(5) in 1960 to 29/10(5) in 1965, a decrease to 14/10(5) in 1975, and a slight increase to 15/10(5) in 1989. This trend was reflected only by patients with insulin treated diabetes mellitus aged > or = 30 yrs. Patients of the age groups 0-9 yrs., 10-19 yrs., and 20-29 yrs. exhibited increasing rates of 0.21/10(5)/year (1960-75), 0.22/10(5)/year, and 0.08/10(5)/year (1960-89), respectively. The rise in the prevalence rate from 187/10(5) (1960) to 658/10(5) (1989) demonstrated temporal trend variations during the periods 1960-71 (+19.3/10(5)/year), 1972-77 (-0.8/10(5)/year), and 1978-89 (+25.6/10(5)/year). The age-specific increasing prevalence trend varied between +0.81/10(5)/year (0-9 yrs.) and +48.89/10(5)/year (60-69 yrs.). The differences observed between incidence and prevalence trends were mainly due to changes in relative mortality rates of patients with insulin treated diabetes and the percentage of secondarily insulinized Type 2 diabetic patients. In summary, the incidence of Type 1 diabetes mellitus in East-Germany increased over the past 3 decades of registration by about 94% in children and adolescents, by 38% in adults aged 20-29 yrs., but not in people aged > or = 30 yrs.(ABSTRACT TRUNCATED AT 250 WORDS)