DIABETES-MELLITUS IN DANISH CYSTIC-FIBROSIS PATIENTS - PREVALENCE AND LATE DIABETIC COMPLICATIONS

The prevalences of impaired glucose tolerance (IGT), diabetes mellitus and late diabetic complications were studied in all Danish cystic fibrosis (CF) patients. A total of 311 CF patients were identified with an estimated ascertainment rate above 98%. Glucose tolerance was classified in 278 (89%) patients: the prevalences of IGT and diabetes mellitus were 13.7% (38 patients) and 14.7% (41 patients), respectively, with no sex differences. The prevalence of diabetes mellitus increased with age but not with the severity of CF as compared with age- and sex-matched non-diabetic CF patients. Diabetes was diagnosed at a median age of 20 years (range 3-40 years) and the duration of diabetes was 1.7 years (0.1-17 years). Twenty-eight of the diabetic patients (70%) were treated with insulin, on average 20 (4-90) IU per day. Late diabetic complications were identified in 4 patients (10%) with a duration of diabetes mellitus of 1-17 years: background retinopathy (2 patients), diabetic nephropathy (1 patient), microalbuminuria(I patient) and neuropathy (2 patients). Thus diabetic CF patients are probably not less prone-to develop late diabetic complications than patients with other types of diabetes of equally long duration and comparable glycemic control.