Prevalence of abnormal urinary albumin excretion in adolescents and children with insulin dependent diabetes: The MIDAC study

Abstract

Objective - To examine the prevalence of microalbuminuria, defined as an albumin to creatinine ratio (UAC) equal to or greater than 2 mg/mmol in at least two of three early morning urine samples, in adolescents and children with insulin dependent diabetes mellitus. Design - Centrally coordinated, cross sectional, multicenter study in paediatric diabetes outpatient clinics in the United Kingdom and Republic of Ireland. Methods - Blood and urine samples collected between July 1997 and July 1998 were analysed at a central reference laboratory for HbA(1C) using high performance liquid chromatography, and for urinary albumin and creatinine concentrations from which the UAC was derived (mg/mmol). Clinical data were collected locally and coordinated centrally. Subjects - Patients, aged between 10 and 20 years, with insulin dependent diabetes mellitus for more than a year, attending diabetes outpatient clinics. Results - A total of 1007 patients, comprising 69% of the eligible population of 1451, provided three early morning urine samples. Ninety eight (9.7%) had micro-albuminuria using the currently accepted screening cut off of UAC ≥ 2 mg/mmol in at least two of three early morning urine samples. Significantly more girls than boys and significantly more pubertal and postpubertal patients had abnormal albumin excretion. Microalbuminuria was not associated with raised blood pressure. Conclusions - A prevalence of 9.7% for abnormal UAC was found in a cohort of 1007 children and adolescents aged 10-20 years. Thus a tenth of this national sample of young people were identified as being at particular risk of microvascular and later macrovascular disease.