Avaliação da aptidão física, força muscular periférica, atividade física habitual e uso de antibióticos em pacientes com fibrose cística

Abstract

INTRODUCTION: Cystic fibrosis (CF) is an autosomal recessive genetic disease with chronic inheritance and systemic manifestations that compromises the normal function of several organs and systems, including the respiratory system. Thus, the progression of lung disease is still the factor of greater morbidity, leading to the reduction of exercise capacity. OBJECTIVES: To evaluate the physical and muscular performance of individuals with cystic fibrosis. METHODS: This is an observational cross-sectional study performed at a cystic fibrosis center. The sample was selected by convenience, including patients with clinical diagnosis of CF (sweat test and/or genetic evaluation) of both genders and aged ≥ 6 years. Patients were referred to perform the cardiopulmonary exercise test (CPET). In addition, demographic data (age and sex), anthropometric data (weight, height and BMI), pulmonary function (spirometry), genetic mutation and clinical information (pancreatic insufficiency and chronic colonization by Pseudomonas aeruginosa) were collected. At the end of the visit, the peripheral muscle strength test and the physical activity questionnaire were performed. Finally, the total number of days of antibiotic use (oral and intravenous) was recorded in the period of one year following CPET evaluation. RESULTS: Thirty-five patients with CF were evaluated. In general, pulmonary function data (% of predicted) were within the limits of normality, obtaining a mean of 83.1 for the forced expiratory volume in the first second (FEV1) and 90.4 for the forced vital capacity (FVC). Only 15 and 10 subjects presented FEV1 and FVC scores below normal, respectively. Regarding CPET, the mean maximum oxygen consumption (VO2max) (%) in the anaerobic threshold was 67.3, heart rate (bpm) was 154.3 and maximum ventilation (L/min) was 30.8. At peak exercise, we found a mean HRmax (% predicted maximum) of 90.2, a respiratory exchange coefficient of 1.1 and VO2max (% predicted) of 102.3, indicating the performance of a maximum test. Only 5 participants presented VO2max results below normal. No subjects had desaturation during and/or after the test. In the evaluation of the peripheral muscle strength (Kgf), we found an average around 20, for both biceps and quadriceps isometric strength. Regarding the physical activity questionnaire, we found habitual levels below recommended, obtaining a median of 30 and 102.5 minutes for moderate and vigorous activities, respectively. Of these, 10/24 were classified as inactive through this instrument. Although there were no correlations between FEV1 (p=0.063) and the use of antibiotic therapy with VO2max at peak exercise, there were weak and significant correlations of FVC with VO2max. Similarly, although there were no VO2max correlations at peak exercise with peripheral muscle strength data, we found moderate and significant correlations of VO2 at the anaerobic threshold with biceps and quadriceps isometric strength. No correlation was found between this variable and the strength of the hamstrings. Finally, subjects with a higher ventilatory reserve and lower resting heart rate did not require the use of antibiotics (ATB) one year after CPET. There was no significant differences FEV1 data were compared. CONCLUSION: The findings of the study demonstrated significant correlations of VO2 at the anaerobic threshold with peripheral muscle strength, showing that the higher the level of physical conditioning, the greater the results of peripheral muscle strength. It was also found that after one year of the proposed evaluations, those who had lower resting heart rate and greater ventilatory reserve in CPET did not require antibiotic therapy.