Association Between Neutrophil-to-Lymphocyte Ratio and Sarcopenia: A Systematic Review and Meta-Analysis.

OBJECTIVES

To clarify the association between the neutrophil-to-lymphocyte ratio (NLR), a marker of systemic inflammation, and sarcopenia by systematically reviewing and meta-analyzing existing evidence.

DESIGN

Systematic review and meta-analysis.

SETTING AND

PARTICIPANTS

This review included 39 observational studies, comprising a total of 17,844 adult participants.

METHODS

A comprehensive literature search was conducted using Web of Science, PubMed, Ovid MEDLINE, and Ovid Embase from inception through March 2025. Eligible studies were evaluated for quality, and either fixed-effects or random-effects models were applied depending on heterogeneity. Forest plots were constructed to assess the association between NLR and sarcopenia. Subgroup analyses, sensitivity analyses, and tests for publication bias were also performed.

RESULTS

Meta-analysis revealed that individuals with sarcopenia exhibited significantly elevated NLR levels compared with those without sarcopenia (standardized mean difference, 0.22; 95% CI, 0.18-0.27; P < .001). A high NLR was also associated with an increased risk of sarcopenia (odds ratio, 1.79; 95% CI, 1.49-2.14; P < .001). Subgroup and sensitivity analyses consistently supported this association. Although publication bias was detected in studies comparing NLR levels, the trim-and-fill method indicated that the effect size remained robust. No significant publication bias was found in analyses evaluating the risk of sarcopenia between high and low NLR groups.

CONCLUSIONS AND IMPLICATIONS: These results suggest a significant association between NLR and sarcopenia. Adults with sarcopenia tend to exhibit higher NLR values, and elevated NLR is associated with increased sarcopenia risk. In cancer populations, an NLR ≥3.0 may serve as a valuable marker for identifying individuals who need further assessment for sarcopenia risk. However, these findings require validation through well-designed, multicenter prospective studies.