Avaliação da função neuromuscular e estresse oxidativo de pessoas com doença renal crônica no início do tratamento hemodialítico

Abstract

Introduction: Chronic kidney disease (CKD) often evolves silently at different stages, and stage 5 is the most advanced and severe, usually requiring renal replacement therapy. As the disease progresses, the metabolic alterations resulting from reduced renal function can lead to neuromuscular disorders and reduced functional performance in this population. Objectives: To assess neuromuscular function and oxidative stress in people undergoing an unplanned transition to stage 5 CKD at the start of hemodialysis. Methods: Cross-sectional study evaluating neuromuscular function (functional capacity [1-minute sit-to-stand test], peripheral muscle strength [isometric dynamometry of lower limbs], respiratory muscle strength [manovacuometry] and neuromuscular excitability [stimulus electrodiagnostic test]) and oxidative stress [malondialdehyde] in people in unplanned transition to stage 5 CKD who started hemodialysis on an emergency basis (CKD group) compared to people without CKD (control group) and them association. Results: Twenty-four participants, 14 in the control group without CKD (42 ± 12 years) and 14 in the CKD group (53 ± 18 years), were evaluated. The CKD group compared to controls without CKD present impaired functional capacity (13.8 ± 4.9 vs 36.7 ± 9.1 repetitions, p < 0.001), on peripheral muscle strength of lower limbs (knee extenders [12.3 ± 4.6 vs 23.5 ± 9 kgf], knee flexors [11.3 ± 3.2 vs 17.8 ± 4.3 kgf], dorsiflexors [8.7 ± 2.8 vs 16.7 ± 4.3 kgf] and plantar flexors [11.2 ± 2.5 vs 16.6 ± 4.4 kgf], all p < 0.001), expiratory muscle strength (60 ± 23 vs 83 ± 27 cmH2O, p = 0.02) and neuromuscular excitability (chronaxy of the vastus lateralis, 654 ± 230 vs 415 ± 190 μs, p = 0.008; chronaxy of the tibialis anterior, 600 [500 – 1000] vs 400 [300 – 400] μs, p = 0.001),. Inspiratory muscle strength (-70 ± 33 vs -87 ± 29 cmH2O, p = 0.7) and oxidative stress (3.51 ± 1.13 vs 3.53 ± 0.92 nmol/ml, p = 0.95) showed no significant differences. In the CKD group, functional capacity was influenced only by peripheral muscle strength, while expiratory muscle strength and functional capacity demonstrated influence on peripheral muscle strength. Conclusion: People in unplanned transition to stage 5 CKD who start hemodialysis on an emergency basis have altered in neuromuscular function. The findings of this study can guide screening and monitoring strategies for neuromuscular deficiencies and rehabilitation planning.