Impact of cystic fibrosis on blood lactate level, respiratory muscle function, peripheral strength and nutritional status in children and adolescents

Abstract

Introduction: Individuals with cystic fibrosis (CF) have digestive, pulmonary and muscular system manifestations, resulting in functional and clinical repercussions, such as changes in the nutritional status, in the strength and endurance of the respiratory muscles and in the oxidative capacity. The objective of this study was to compare blood lactate level, respiratory muscle strength and endurance, peripheral strength and nutritional status among children and adolescents with CF and healthy ones, as well as to correlate the lactate level with respiratory and peripheral muscle forces and respiratory muscle endurance of children and adolescents with CF. Methods: In an observational, analytical and cross-sectional study, 22 children and adolescents (11 healthy and 11 with CF) were divided into two groups according to the diagnosis of CF. Blood lactate level, inspiratory and expiratory muscle strength, respiratory muscle endurance, peripheral muscle strength and nutritional status were evaluated. Data analysis was performed using Students t test, Mann-Whitney, Pearson and Spearman correlations, with SPSS (25.0), adopting a significance level of 5%. Results: Children and adolescents with CF presented high levels of blood lactate (p=0.000), decreased maximum inspiratory pressure (p=0.006), deterioration of nutritional status (p=0.000) and also they did not show any difference in peripheral strength (p=0.365) and respiratory endurance (p=0.716). Conclusions: Individuals with CF have high levels of blood lactate, with significant impairment of nutritional status and respiratory muscle function compared to healthy individuals. However, the high lactate levels are not related to respiratory and peripheral muscle strength and respiratory endurance.