Loss of muscle strength in patients under hemodialysis evaluated by dynamometry in the Mexican population

Introduction: chronic kidney disease contributes to decreased muscle strength and physical function through a decrease in muscle mass. Current evidence suggests that hemodialysis can accentuate this complication, as well as lead to deterioration of the patient's overall health. The aim of this study is to compare muscle strength in a group of Mexican patients undergoing hemodialysis, evaluated by dynamometry, with available reference values. Materials and methods: a cross-sectional study was conducted in male and female patients between 20 and 81 years of age, with stage-5 chronic kidney disease, from the outpatient Hospital General Regional No 46 of the Mexican Social Security Institute. Muscle strength was assessed by means of a mechanical dynamometer. The average value classified by age and gender was compared with the 50th percentile of a reference study. Inter-group differences were calculated with the nonparametric Mann-Whitney U-test, and correlation using Pearson's test, logistic regression, and chi-squared test. All patients signed an informed consent form. Results: a total of 150 patients, 97 (64.7 %) men and 53 (35.3 %) women, were included in the study. The mean dynamometric value for muscle strength was 21.5 ± 10.1 kg, and a significant correlation was found with age, weight, and hemoglobin concentration. Conclusion: patients undergoing hemodialysis treatment for chronic kidney disease were found to be at the 10th percentile for muscle strength, as measured by dynamometry, thus demonstrating a marked decrease in muscle strength. This result could, however, also have been affected by different variables such as patient age, height, weight, glomerular filtration rate (GFR), hemoglobin concentration, serum creatinine, serum glucose, and the subjective global assessment, given that a significant association was also found between these and muscle strength.