MULTICENTER RANDOMIZED STUDY ON THE EFFECT OF A LOW-PROTEIN DIET ON THE PROGRESSION OF RENAL-FAILURE IN CHILDHOOD - ONE-YEAR RESULTS

After an adaptation period of 6 months, 200 children (mean age 10.3 years; 138 boys and 62 girls) were stratified according to their renal diseases and the progression of renal failure during the adaptation period and randomized for low protein intake amounting to the WHO safe levels for age (0.8-1.1 g/kg/day) or free protein intake. Energy intake of both groups should be near the WHO recommendations. Compliance was controlled by written dietary diaries and urea-N excretion. 101 children had been randomized for the diet group and 99 for the control group. 165 of these patients finished their first year after randomization. Mean protein intake was 126% of the recommendations in the diet group vs. 187% in the control group while energy intake was similar in both groups (85 vs. 90%). SDS for height at start and 1 year later did not change (diet: -0.9 vs. -1.1; control: -0.9 vs. -0.9). Weight gain was not different. Only the stratification for two groups according to the progression of renal failure ('nonprogressive' and 'progressive' diseases) was used in the analyses. Progression of renal disease during the adaptation period proved to be a significant prognostic factor. Mean loss of GFR/year was similar in patients with 'nonprogressive' diseases in the control group (-1.1 ml) and the diet group (-1.3 ml). In patients with 'progressive' diseases mean loss of GFR was significantly higher in the diet group (-6.5 ml) than in the control group (-4.0 ml). But, analysing the patients according to their urea-N excretion eliminated this difference ('nonprogressive' diseases: low urea-N excretion: -2.24 ml vs. high urea-N excretion: -0.79 ml; 'progressive' diseases low urea-N excretion: -4.76 ml vs. high urea-N excretion: -5.54 ml). In summary, there was no obvious disadvantage or advantage for low protein intake during the first year of observation.