1. Introduction
proteinuria
RENAL, GLOMERULOSCLEROSIS, KIDNEY, SECONDARY, KIDNEY HYPERTROPHY
High protein intake has been associated with kidney hypertrophy, which is usually reversible; however, when it occurs early in life, it could lead to cell programming with a long-lasting effect. This study aimed to assess whether higher protein ingestion early in life has a persistent effect on kidney volume at 11 years of age, as well as its influence on blood pressure. This is a secondary analysis of a randomized control trial that compared the growth of infants fed with a higher-protein formula versus those fed with a lower-protein formula, with a control group of breastfed infants. Renal ultrasound and anthropometric measurements were assessed at 6 months and 11 years of age. At 11 years, urinary protein, albumin and creatinine, and blood pressure were measured in 232 children. Feeding with a higher-protein formula was associated with a larger kidney volume (β = 8.71, 95%CI 0.09–17.33, Kidney development is highly influenced by nutritional factors during nephrogenesis. Barker’s hypothesis proposed that a poor nutrient supply during a critical period of in utero life may “program” a permanent structural or functional change in the fetus, thereby altering the distribution of cell types, gene expression, or both [Animal experimental models demonstrated that higher chronic protein ingestion (after nephrogenesis had ended) increased the kidney volume and glomerular filtration rate, and eventually proteinuria and glomerulosclerosis. This effect was more evident in animals with less nephron endowment [In a previous study, we showed that, at 6 months of life, infants fed with a higher-protein-content formula had a significantly higher kidney volume, ratios of kidney volume to body length, and kidney volume to body surface area than those breastfed or fed with formula containing lower protein with no significant differences in eGFR [The aim of the present study was to assess whether the protein-induced kidney growth early in life persisted to a later age, ten years after the end of the intervention, and if early kidney growth differences influenced blood pressure at 11 years of age.