Reference Values for Lower-Limb Dynamometry in Patients With Chronic Kidney Disease (REHAD-CKD)

Patients with chronic kidney disease (CKD) undergoing hemodialysis present musculoskeletal complications, such as sarcopenia, which impair their functionality and are associated with an increased risk of mortality. Functional assessment in this population is complex due to the organization of hemodialysis schedules and patients' dependence on medical transportation, which hinders evaluation outside the dialysis setting. The assessment of lower limb strength is of great relevance, as an adequate level of muscle strength in this region is essential for performing many activities of daily living, including walking, sit-to-stand and stand-to-sit movements, as well as ascending and descending stairs. Our research group has published a study demonstrating the safety and reliability of intradialytic measurement of hip flexion and abduction strength; however, reference values for the dialysis population and for individuals with CKD in general are currently unknown. The primary aim of this study is to propose reference values for hip flexor and abductor muscle strength measured using a hand-held dynamometer in individuals with chronic kidney disease (CKD). Secondary objectives include assessing the association between lower limb muscle strength measured with a hand-held dynamometer and handgrip strength, physical activity level, frailty, gait speed, performance in the 10-repetition sit-to-stand-to-sit test, ultrasound assessment of the rectus femoris muscle, and health-related quality of life.

Inclusion Criteria: * ≥1 months on HD (3 weekly sessions of 4 hours) Exclusion Criteria: * Lower-limb amputation; * Neurological, musculoskeletal or osteoarticular disorders; * Severe/unstable comorbidities (e.g., decompensated heart failure or diabetes, unstable angina, recent MI, uncontrolled hypertension, severe lung disease, acute infection); * \