Bioelectrical impedance analysis for sarcopenia: a systematic review and meta-analysis of diagnostic accuracy.

Objective: To evaluate the diagnostic performance of bioelectrical impedance analysis (BIA) for detecting sarcopenia across diverse populations.

Methods: We conducted a search of MEDLINE, Embase, and Web of Science up to 2 January 2024. Cross-sectional, retrospective, and prospective cohort studies evaluating BIA's diagnostic performance for detecting sarcopenia across diverse populations were included. The pooled sensitivity, specificity, positive and negative likelihood ratios (positive likelihood ratio [PLR] and negative likelihood ratio [NLR]), diagnostic odds ratio (DOR), and the area under the curve of summary receiver operating characteristic (SROC-AUC) were calculated using bivariate random-effects models. For each outcome, 95% confidence intervals (CI) were reported.

Results: A total of 27 studies involving 6239 participants were included. The pooled sensitivity was 79% (95% CI, 75%-82%), and the pooled specificity was 72% (95% CI, 68%-75%). The pooled PLR was 2.8 (95% CI, 2.5-3.1), the pooled NLR was 0.29 (95% CI, 0.25-0.35), and the pooled DOR was 9 (95% CI, 7-12). The SROC-AUC was 0.82 (95% CI, 0.78-0.85). Sensitivity analysis confirmed the robustness of these results. Heterogeneity was observed, which was attributable to variations in clinical and methodological factors.

Conclusions: This systematic review indicates that BIA has moderate diagnostic accuracy and practical clinical utility as a screening tool for sarcopenia, particularly in primary care and community settings. Further research is warranted to develop standardised protocols and predictive models to enhance consistency and reliability across populations.