BACKGROUND AND AIMS Sarcopenia is a risk factor for adverse outcomes in older adults,[1], but this has yet to be confirmed in chronic kidney disease (CKD).[2] We conducted a systematic review to investigate the association between sarcopenia and its traits with mortality, hospitalization and end-stage kidney disease (ESKD) progression in CKD patients.

METHOD Five electronic databases were searched, including MEDLINE and Embase. Observational cohort studies with CKD patients were included. The sarcopenia traits assessed were low muscle strength, low muscle mass and low physical performance, as well as confirmed sarcopenia (combined low muscle mass and low strength/performance).[3] Hazard ratios (HR), risk ratios (RR), odds ratios (OR) and 95% confidence intervals (CI) were pooled using random-effect meta-analyses.

RESULTS From a total of 4922 screened studies, 50 (72 347 patients) were included in the review and 38 (59 070 patients) in the meta-analyses. Most of the included studies were in dialysis patients (n = 29, 58%). Table 1 shows that low muscle strength (15 studies; HR: 1.99; 95% CI: 1.65–2.41; I²:45%), low muscle mass (20 studies; HR: 1.51; 95% CI: 1.36–1.68; I²: 26%), low physical performance (five studies; HR: 2.09; 95% CI: 1.68–2.59; I²: 0%) and confirmed sarcopenia (eight studies in dialysis patients; HR: 1.87; 95% CI: 1.35–2.59; I²: 40%) were associated with an increased mortality risk. On the other hand, for dialysis patients it was uncertain whether low muscle mass was associated with hospitalization (two studies; RR: 1.81; 95% CI: 0.78–4.22; I²: 59%). Further, limited ESKD progression measures prevented meta-analysis for this outcome.

CONCLUSION Low muscle strength, low muscle mass and low physical performance are associated with higher mortality in CKD patients. In dialysis patients, confirmed sarcopenia also represented higher mortality risk. Evidence to conclude associations with hospitalization and ESKD progression are currently lacking.

CI, confidence interval