Patients receiving maintenance dialysis have more severe functionally significant skeletal muscle wasting than patients with dialysis-independent chronic kidney disease

Abstract

Background. Chronic renal replacement therapy patients exhibit reduction in skeletal muscle function as a result of a combination of metabolic effects and muscle fibre size reduction. The aim of this study was to compare muscle mass with function in patients with chronic kidney disease (CKD) at stages 4 and 5 on haemodialysis (HD) and peritoneal dialysis (PD), and investigate the associations of muscle wasting in a cross-sectional cohort. Methods. We studied 134 patients (60 HD, 28 PD and 46 CKD 4). The three groups were well matched for age, sex, diabetes and dialysis vintage. Cross-sectional area (CSA) of muscle and fat was measured from a standardized multi-slice CT scan of a 6 cm long section of thigh. CSA of soft tissue was taken from appropriate fat and muscle densities. Functional assessment was by the sit-to-stand 60 test, assessing both the number of sit-to-stands possible under controlled conditions in 60 s (STS 60), and the time taken to perform five sit-to-stand movements (STS 5). Data were collected on a wide range of potential determinants of muscle CSA. Results. There were no significant differences in haemoglobin between males or females or between any of the groups studied. Serum phosphate and calcium-phosphate product were higher in HD patients as compared to CKD4 patients, but there were no differences in these variables when comparing PD patients with either CKD4 or HD patients. Muscle CSA correlated well with objective functional assessments in males (STS 60 R ¼ 0.52, P<0.0001) and females (R ¼ 0.41, P ¼ 0.004), and STS performance was reduced in dialysed patients as compared with CKD 4. Univariate analysis demonstrated that muscle CSA was associated with serum albumin concentration (R ¼ 0.49, P<0.0001), age (R ¼ À0.35, P ¼ 0.005) and C-reactive protein (R ¼ À0.34, P ¼ 0.004). Creatinine clearance, dialysis adequacy, dialysis vintage and time-averaged serum bicarbonate, calcium and phosphate concentrations were not correlated with muscle CSA. Conclusion. In conclusion, patients with dialysis-treated CKD 5 exhibited more functionally significant muscle wasting than patients with CKD 4. This may be amenable to modification with targeted exercise or amelioration of factors associated with observed differences in muscle mass.

Efeitos negativos da insuficiência renal crônica sobre a função pulmonar e a capacidade funcional

“…Among them are decreased protein-calorie intake, muscle atrophy through disuse and muscle protein imbalance, which mostly affect type II muscle fibers; reduction of the vascular and capillary bed; presence of intravascular calcification and decreased local blood flow. These results are part of the pathogenesis of uremic myopathy and are commonly described in the literature in relation to skeletal muscles such as the deltoid, quadriceps and abdominal muscles [4][5][6][7][8][9] .…”

Força muscular respiratória e capacidade funcional na insuficiência renal terminal

“…As manifestações da síndrome urêmica afetam negativamente a capacidade funcional (12,27,28) , a qualidade de vida (13)(14)(15) , a força muscular respiratória (12,13,29) e função pulmonar (30,31) , fato que pode estar associado à diminuição da força muscular periférica evidenciada em pacientes com IRT (9,32) . Assim como em outros trabalhos (8,13) , os pacientes apresentaram redução da PEmax em relação ao previsto pelas equações de Neder et al (24) .…”

“…Pacientes com IRT sofrem de um conjunto de alterações em vários sistemas orgânicos, denominado de "síndrome urêmica" (5) , o qual envolve uremia, anemia, doenças cardiopulmonares (6) , alterações metabóli-cas, disfunção musculoesquelética (miopatia urêmica) (7) , comprometimento físico, imunológico e psíquico (5,8) . Esse fenômeno compromete a qualidade de vida e limita as atividades de vida diária, com aumento da taxa de mortalidade nessa população (9)(10)(11) . A redução das medidas de pressão inspiratória e expiratória máxima (8) , representando a fraqueza muscular respiratória em pacientes com IRT, está associada à redução da capacidade funcional (11,12) e da qualidade de vida (13)(14)(15) .…”

Intradialytic exercise and postural control in patients with chronic kidney disease undergoing hemodialysis

“…Concomitant to these characteristics, the clinical profile of these patients is also associated with reduced muscle strength and endurance (8). There is a consensus that patients on dialysis have lower exercise tolerance and loss of functional capacity (9,10).…”