New approaches in the nutritional treatment of advanced chronic kidney disease.

Introduction: Patients with advanced chronic kidney disease (ACKD) have a high prevalence of malnutrition. The dietary restrictions that we usually apply in terms of macro and micronutrients force our patients to follow dietary guidelines that deviate from healthy patterns.
Objetives: To determine if a personalized nutritional intervention program, minimizing the usual restrictions would be justified in case it improved the evolution of kidney disease compared to standard treatment.
Secundary Objetives: To determine changes in nutrient intakes and in anthropometric and biochemical parameters, as well as quantify episodes of hyperkalemia.
Material and Methods: A single-center, randomized and controlled educational intervention clinical trial was conduct in patients from the ERCA outpatients clinic at the Complejo Hospitalario Universitario de Albacete. 75 patients were included, assigning 35 to a Control group and 40 to the Intervention group with 1-year follow-up. The nutritional status was determined using anthropometric data, body composition by Bioimpedance, blood and urine biochemical parameters and a 24-h recall questionnaire. The nutritional intervention was carried out in three different ways: individual, collective and telephone recall.
Results: At the beginning of the study, the BMI showed a situation of weight excess with a mean of 28.83 kg/m ² (5.4) in men and 26.96 kg/m ² (4.09) in women. 70% of our patients had overweight. The abdominal circumference was 105.3 cm (10.2) and 92.3 cm (13.7) for men and women respectively without significant changes throughout the study. The percentage of fat mass (FM) was high in both groups for men and women throughout the study. We did not find biochemical parameters of malnutrition and only significant differences were observed in glomerular filtration rate (GFR), which increased in the intervention group. No patient presented any episodes of hyperkalemia during the study. The energy intake in both groups showed an inadequate distribution of macronutrients with a poor intake of carbohydrates (CH) that was supplemented with an excess of fat. In the case of micronutrients, we did observe an increase in potassium and fiber intakes with a decrease in sodium and phosphorus in the intervention group.
Conclusions: Malnutrition is not exclusively an intake defficit and encompasses both the problems derived from a deficit and an excess of nutrients intake. Un to 70% of our patients showed weight excess and a fat mass higher than desirable. The implementation of an individualized nutritional education program, including a vegetables and fiber rich diet, less atherogenic, not only did not cause electrolyte alterations but also slowed the progression of kidney disease.
(Copyright © 2021 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.)