Factors Associated With Microalbuminuria in 7,549 Children and Adolescents With Type 1 Diabetes in the T1D Exchange Clinic Registry

OBJECTIVE To examine factors associated with clinical microalbuminuria (MA) diagnosis in children and adolescents in the T1D Exchange clinic registry.

RESEARCH DESIGN AND METHODS T1D Exchange participants <20 years of age with type 1 diabetes ≥1 year and urinary albumin-to-creatinine ratio (ACR) measured within the prior 2 years were included in the analysis. MA diagnosis required all of the following: 1) a clinical diagnosis of sustained MA or macroalbuminuria, 2) confirmation of MA diagnosis by either the most recent ACR being ≥30 mg/g or current treatment with an ACE inhibitor (ACEI) or angiotensin receptor blocker (ARB), and 3) no known cause for nephropathy other than diabetes. Logistic regression was used to assess factors associated with MA.

RESULTS MA was present in 329 of 7,549 (4.4%) participants, with a higher frequency associated with longer diabetes duration, higher mean glycosylated hemoglobin (HbA_1c) level, older age, female sex, higher diastolic blood pressure (BP), and lower BMI (P ≤ 0.01 for each in multivariate analysis). Older age was most strongly associated with MA among participants with HbA_1c ≥9.5% (≥80 mmol/mol). MA was uncommon (<2%) among participants with HbA_1c <7.5% (<58 mmol/mol). Of those with MA, only 36% were receiving ACEI/ARB treatment.

CONCLUSIONS Our results emphasize the importance of good glycemic and BP control, particularly as diabetes duration increases, in order to reduce the risk of nephropathy. Since age and diabetes duration are important nonmodifiable factors associated with MA, the importance of routine screening is underscored to ensure early diagnosis and timely treatment of MA.