Glomerular Filtration Rate Abnormalities in Children With Type 1 Diabetes

Type 1 diabetes (T1D) increases the risk of chronic kidney disease (CKD) development. The primary objective of this study was to assess the prevalence of abnormalities in estimated glomerular filtration rate (eGFR) in children with T1D. As a secondary objective, we sought to explore the relationship between clinical characteristics and abnormalities in eGFR.

This cross-sectional study involved children ≤18 years of age with T1D followed in the diabetes clinic at a pediatric tertiary care centre. Data were collected from health records between 2016 and 2020. Using the Bedside Schwartz, Chronic Kidney Disease in Children Under 25 (CKiD U25) and European Kidney Function Consortium (EKFC) equations, eGFR was categorized as CKD (<60 mL/min/1.73 m²), mildly decreased (60 to <90 mL/min/1.73 m²), normal (90 to <158 mL/min/1.73 m²) and hyperfiltration (≥158 mL/min/1.73 m²). Linear regression analysis was used to describe the relationship between eGFR and clinical characteristics.

Of the 420 participants, 225 were male (54%); the median age at diagnosis and duration of T1D were 6.1 and 4.8 years, respectively. The proportion of participants with mildly decreased eGFR was similar regardless of eGFR equation, with 11% to 14% of participants with an eGFR <90 mL/min/1.73 m². When analyzed as a function of duration of T1D, eGFR was 1.4 mL/min/1.73 m² lower per year duration of T1D.

A notable proportion of children with T1D demonstrates eGFR abnormalities early in their T1D course. This finding along with evidence of lower eGFR in adolescence is concerning for long-term risk of CKD and warrants systematic serum creatinine monitoring at diagnosis and regular intervals thereafter in children with T1D.