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.