Weight trajectories and kidney function in early childhood.

INTRODUCTION: Postnatal growth profile is believed to have an impact on the risk of later obesity and of cardiovascular and kidney disease. We aimed to study the association between different trajectories of weight gain during infancy and early childhood and the renal function in prepubertal children. METHODS: Longitudinal study of 1,004 children aged 7-9 years, divided into four groups of weight gain trajectories from birth to 6 years (I: eutrophic/reference; II: early-onset persistent accelerated weight gain; III: childhood-onset accelerated weight gain; and IV: early transient weight gain). Glomerular filtration rate (GFR) was estimated by several formulas using serum creatinine (Cr) and/or cystatin C (CysC), and by 24-hour creatinine clearance (CrCl). RESULTS: Individuals in trajectory I presented the lowest Cr and CysC and the highest estimated GFR (eGFR) values, while trajectory II included those with the lowest eGFR, estimated by the Filler and Le Bricon formulas. Trajectory I individuals presented the lowest absolute CrCl values, while those in trajectory II presented the highest values. In multivariate linear regression models adjusted for age, sex, birth weight-for-gestational-age category, blood pressure, and current body mass index, trajectory III was associated with an eGFR that was 2.68 to 3.75 mL/min/1.73 m2 lower than that of trajectory I in the two models based on CysC. CONCLUSIONS: Children with early-onset persistent or childhood-onset accelerated weight gain presented significantly lower eGFR, which supports the influence of childhood growth patterns on later kidney function.