Metabolic control and prevalence of microvascular complications in young Danish patients with Type 1 diabetes mellitus

Aims. After Danish nationwide investigations (1987, 1989) demonstrated unac ceptable brood glucose control in unselected young diabetic patients, we se t out to estimate the present glycaemic control and the prevalence of micro vascular complications in a cohort of children and adolescents participatin g in the two previous studies. Methods. This follow-up represents 339 patients (47% of the inception cohor t), median age 21.1 years (range 12.0-26.9), median diabetes duration 13.2 years (range 8.9-24.5). A standardized questionnaire, fundus photographs (w ith central reading) and a physical examination were performed. HbA(1C) and overnight albumin excretion rate (AER) were analysed centrally. Results. Although 88% (n = 309) of the young persons were treated with thre e or more daily insulin injections, HbA(1C) (nondiabetic range 4.3-5.8, mea n 5.3%) was 9.7 +/- 1.7% (mean +/- SD). Males had higher HbA(1C) values tha n females (P < 0.015). Mean daily insulin dose was 0.92 +/- 0.25 IU.kg(-1). 24h(-1). Microalbuminuria (AER > 20-150 mu g/min) and macroalbuminuria (AER > 150 mu g/min) were found in 9.0% and 3.7% of the patients, respectively, and was associated with increased diastolic blood pressure (P < 0.01) and presence of retinopathy (P < 0.01). Retinopathy was present in approximate to 60% of the patients and was associated with age, diabetes duration, HbA( 1C), diastolic blood pressure and AER (all P < 0.01). Subclinical neuropath y (vibration perception threshold by biothesiometry > 6.5 V) was found in 6 2% and showed a significant association with age, linear height, diastolic blood pressure (all P < 0.01) and diabetic retinopathy (P = 0.01). Conclusions. In spite of the majority of the patients being on multiple ins ulin injections, only 11% had HbA(1C) values below 8% and the prevalence of diabetic microvascular complications in kidneys, eyes and nerves was unacc eptable high.