Consumo alimentar em portadores de doença renal crônica em tratamentos conservador: carga ácida da dieta e grau de processamento dos alimentos

Abstract

The progressive loss of renal functions leads to the inability of the kidney to eliminate nitrogenous wastes, regulate fluid balance, produce the hormone erythropoietin and maintain electrolytes and acid-base equilibrium. The food consumption is involved in metabolic acidosis due to food-derived acid-base absorption. Western diet, spreading in developing countries as Brazil, is typified by food of animal origin and industrialized products consumption and low consumption of fruit and vegetables. This dietary pattern is strongly related to the formation of acid precursors in the organism, disturbing acid-base equilibrium and favoring the development of metabolic acidosis and other comorbidities related to CKD. Furthermore, higher consumption of ultra-processed food has been related to higher risk of mortality. Objectives: To assess food consumption of people who have chronic kidney disease by the dietary acid load and levels of processing foods. Methodology: Epidemiologic study of cross-sectional design, including bearers of CKD in stages from 3 to 5. The following data were obtained: socioeconomic (age, sex and education level), clinical, and anthropometric (weight, height, waist circumference and body composition using bioimpedance analysis by bipolar and tetrapolar techniques) and food consumption data (24-hour food recall - 24HR - and food frequency questionnaire- FFQ). To assess the ingestion of macronutrients and micronutrients, these softwares were used: DIETPRO version 5.0 and Multiple Source Method (MSM). Later, the dietary potential renal acid load (PRAL) equation was used for calculating the dietary acid load. In the assessment of consumption by level of processing, the three following groups were formed: natural foods, minimally processed and culinary ingredients (G1); processed foods (G2); and ultra-processed foods (G3). Results: 176 individuals were assessed. 55.7% were male, 60.2% were in stage 3 of CKD, 44.3% were diabetes mellitus and systemic hypertension carriers and 69.5 ± 11.1 years old in average. 80.7% were elderly, 77.3% were illiterate or have not completed the Brazilian Fundamental Education and 60.2% were overweight. PRAL median was –4.43 (mEq/day), from –29.87 to 20.13. In the multiple linear regression model, the variables usual fiber consumption (ß= -0.68; p < 0.001), lipid consumption (ß= 0.34; p< 0.001) and annual beef consumption (ß= 9.51; p<0.001) independently influenced the dietary PRAL values. The fiber inadequate intake was present in 96,6% and calcium in 100%. The average energy consumption was 1183,71 kcal/day. The participation in the total energy consumption was, on average: 71,32% in G1; 19,22% in G2; and 9,46% in G3. The calorie consumption in G1 was higher in men and in G3 in adults. Conclusion: Fiber consumption contributed to a lesser acid production in the metabolism. Lipid and beef consumption contributed to a higher dietary acid load in patients with CKD under conservative treatment. Low daily energy ingestion was identified and natural foods, minimally processed food and culinary ingredients consumption was higher in males and higher than the ultra-processed food in the adult population.