Occurrence of microalbuminuria in young people with Type 1 diabetes: importance of age and diabetes duration

Abstract

Aims To determine the occurrence of microalbuminuria in young people with Type 1 diabetes mellitus followed prospectively for 2 years and to relate the presence of persistent elevations in urinary albumin excretion (UAE) to age, diabetes duration, puberty and other factors. Methods During a 2 year period, random urine samples were obtained from 471 patients, aged 8–18 years (mean ± SD 12.9 ± 2.3 years) with Type 1 diabetes duration 5.6 ± 3.0 years, as part of routine clinical care. Urine albumin and creatinine concentrations were measured in 1310 samples (median, 3 samples per patient) and the albumin:creatinine ratio was calculated (in micrograms albumin per milligram creatinine). Height, weight, blood pressure (BP), glycated haemoglobin (HbA1c), blood glucose monitoring frequency and Tanner staging were collected from patients’ medical records. Results Twenty-three per cent of patients had one or more sample with elevated UAE (≥20 μg/mg) and 9.3% had persistent elevations (≥2 samples ≥20 μg/mg). Those with and without persistent microalbuminuria did not differ significantly in age, diabetes duration, z–score for body mass index, pubertal status or BP percentile. Ten per cent of children <13 years old and 9% of children ≥13 years old had persistent microalbuminuria. Persistent microalbuminuria was significantly associated with diabetes duration only in older children (duration 0.5–3 years, 4%; 4–6 years, 8%; ≥7 years, 14%; P = 0.02, trend test). Mean HbA1c over the 2 years was 8.7 ± 1.2%. In a logistic regression model, mean HbA1c was the only significant predictor of persistent microalbuminuria (odds ratio 1.3, 95% confidence interval 1.0–1.6, P = 0.05). Conclusions Microalbuminuria in older children with Type 1 diabetes is likely to be clinically significant. In younger children, it may reflect functional, reversible renal changes. Longitudinal analysis is needed to confirm the probable transient nature of microalbuminuria in young patients with Type 1 diabetes.

Natural course of untreated microalbuminuria in children and adolescents with type 1 diabetes and the importance of diabetes duration and immigrant status: longitudinal analysis from the prospective nationwide German and Austrian diabetes survey DPV

“…Other studies have reported similar results: the prevalence rate of microalbuminuria was estimated to be 5.9% in children with a mean age of 12.7 years and a diabetes duration of 5.1 years (4). Another study in children (mean age 12.9 years) has revealed that persistent microalbuminuria was present in 9.3% (13). The present survey also showed that intermittent microalbuminuria was not a predictive factor for the progression of microalbuminuria and that in a real-world setting, intermittent microalbuminuria has little prognostic significance in adolescents with type 1 diabetes (1,4,12,14).…”

“…Several cross-sectional studies demonstrated that 6-25% of patients between 15 and 20 years of age develop microalbuminuria (1,4,8,9,10). Because the natural history of microalbuminuria in adolescents with type 1 diabetes is often not as consistent and clear as in adults, there is ongoing discussion about predictors of persistent microalbuminuria and nephropathy (4,8,11,12,13). Some studies have shown that half of the probands with type 1 diabetes and microalbuminuria have normoalbuminuria at the end of puberty (4,11).…”

Microalbuminuria in pediatric patients with hypertension

“…In other studies even higher percentages of both have been found [43]. Significant association between the occurrence of microalbuminuria or proteinuria and poor glucose control has been confirmed [26,43]. In addition to poor glycemic control, clinical markers of insulin resistance were associated with its development [44].…”

“…Microalbuminuria was most extensively investigated in children with both type 1 and type 2 diabetes [25,26] and its significant role established. In recent years its assessment has been utilized as a screening test for the presence of diabetes-related kidney disease [38].…”

“…Unfortunately, there are no studies yet, investigating the role of microalbuminuria in children as cardiovascular risk factor later in adult life, which is important future task. Anyway, the clinical significance of microalbuminuria in diabetic children has been confirmed [25,26] as well as in some other diseases in children [27][28][29][30]. Some small intervention studies have also been conducted, suggesting that early intervention with medications is likely to be beneficial in children too [31,32].…”