Different alterations of glomerular filtration rate and their association with uric acid in children and adolescents with type 1 diabetes or with overweight/obesity.

BACKGROUND

Hyperfiltration (HF) occurs early in diabetes or obesity (OB)-associated renal disease. Alterations of glomerular filtration rate (GFR) in childhood OB remain unclear.

OBJECTIVES

To compare the prevalence of GFR alterations and its association with uric acid in children and adolescents with type 1 diabetes (T1D) vs overweight (OW)/OB.

METHODS

Cross-sectional study of 29 youths (aged: 13 ± 2 years) with T1D (disease duration: 7 ± 3 years) and 165 with OW/OB (aged: 11 ± 3 years). Patients with an albumin-creatinine ratio >3.39 mg/mmol were excluded. GFR was estimated with creatinine-cystatin C Zappitelli equation. HF and low GFR were defined by a GFR > 135 and <90 mL/min.1.73 m , respectively.

RESULTS

HF was higher in children with T1D vs OW/OB (28% vs 10%, P < .005). Children with OW/OB also showed a 10% of low GFR. In patients with T1D, HbA1c (β = .8, P < .001), and systolic blood pressure (β = 11.4, P < .005) were independent predictors of GFR (R = .65). In OW/OB, HF cases were almost limited to prepubertal children and low GFR to pubertal ones. GFR in OW/OB was associated with age (β = -2.2, P < .001), male sex (β = -11.6, P < .001), and uric acid (β = -.05, P < .001) in adjusted models (R = .33).

CONCLUSIONS

GFR alterations were different between youths with T1D and with OW/OB. Higher uric acid, older age, and puberty were related to lower GFR values in OW/OB children. Longitudinal studies will determine if low GFR is consequence of a rapid GFR decline in pediatric patients with OW/OB.