Muscle power and physical dysfunction: A model for tailoring rehabilitation in chronic kidney disease

Abstract

Introduction: Chronic kidney disease (CKD) is characterized by adverse physical function. Mechanical muscle power describes the product of muscular force and velocity of contraction. In CKD, the role of mechanical muscle power is poorly understood and often overlooked as a target in rehabilitation. The aims of this study were to investigate the association of mechanical power with the ability to complete activities of daily living and physical performance. Method: Mechanical muscle power was estimated using the sit-to-stand-5 test. Legs lean mass was derived using bioelectrical impedance analysis. Physical performance was assessed using gait speed and 'timed-up-and-go' (TUAG) tests. Self-reported activities of daily living (ADLs) were assessed via the Duke Activity Status Index. Balance and postural stability (postural sway and velocity) was assessed using a FysioMeter. Sex-specific tertiles were used to determine low levels of power.Results: One hundred and two non-dialysis CKD participants were included (age: 62.0 (±14.1) years, n = 49 males (48%), eGFR: 38.0 (±21.5) ml/min/1.73m 2 ). The mean relative power was 3.1 (±1.5) W/kg in females and 3.3 (±1.3) W/kg in males. Low relative power was found in 34% of patients. Relative power was an independent predictor of ADLs (β = .413, p = .004), and TUAG (β = À.719, p < .001) and gait speed (β = .404, p = .003) performance. Skeletal muscle mass was not associated with any outcomes. Conclusion:Knowledge of the factors that mediate physical function impairment is crucial for developing effective interventions. Incorporation of power-based training focusing primarily on movement velocity may present the best strategy for improving physical function in CKD, above those that focus on increasing muscle mass.

Predicting hospitalization from real-world measures in patients with chronic kidney disease: A proof-of-principle study

“… 61 In its current form, the 6MWT is a simple, pragmatic assessment and has demonstrated value as a prognosticator of disease severity and predictor of morbidity and mortality in many clinical populations including kidney disease. 17 , 31 , 35 – 41 , 62 – 64 Results from the current study contribute to the large body of evidence supporting the clinical utility of the 6MWT.…”

“…6MWT, gait speed) and sit-to-stand body transfers (e.g. timed-up-and-go), both of which have been shown to differentiate patients with CKD who have difficulties with activities of daily living and those at increased risk for mortality, 17 , 35 – 41 and (2) they are easily measured using a single wearable actigraphy sensor that is acceptable to patients with CKD and can accurately capture other meaningful physical behaviors. 28 Best 6-minute step count (B6SC) was defined as the number of steps during the most active continuous 6-minute period that the activPAL™ monitor was worn.…”

Rehabilitation Nutrition in Patients with Chronic Kidney Disease and Cachexia

“…[71,72]. Recently, muscle power, defined by muscle strength and muscle contraction rate, was reportedly reduced in patients with CKD [73]. Therefore, to improve physical function in patients with CKD, incorporating training that focuses on movement speed may have better results than training to increase muscle mass [73].…”