Long-term impact of sarcopenia in older patients undergoing gastrectomy for gastric cancer: a systematic review and metaanalysis

Background: Sarcopenia is an inevitable problem in older patients. After gastrectomy, patients often have an inadequate dietary intake and easily fall into sarcopenia. However, the impact of preoperative sarcopenia on long-term outcomes after gastrectomy has not been analyzed. Methods: A systematic review was conducted for all relevant articles identified on PubMed, the Cochrane Library, Web of Science, and ClinicalTrials.gov until April 2023. Adjusted hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using the fixed or random effects model according to the heterogeneity. The Newcastle-Ottawa Scale was used to quantify study quality. Results: Seven studies involving 1,831 patients aged =65 years who underwent gastrectomy for gastric cancer were analyzed. Four hundred twelve patients (22.5%) were diagnosed with sarcopenia. The analysis showed that preoperative sarcopenia was significantly associated with poor overall survival (OS) (HR =1.93; 95% CI:1.60-2.34; P<0.001). Two of the included studies also showed that preoperative sarcopenia was significantly correlated with disease-related survival: one with disease-specific survival ( DSS) (HR =4.00; 95% CI: 1.20-13.3, P=0.024) and the other with non-cancer specific survival (HR =3.27; 95% CI: 1.61-6.67; P=0.001). Furthermore, sarcopenic patients experienced more severe complications than non-sarcopenic patients (OR =1.80; 95% CI: 1.10-2.95; P=0.019). Conclusions: This meta-analysis suggested that preoperative sarcopenia is useful as a prognostic factor of impaired OS in older patients after gastrectomy. Preoperative evaluation and intervention for skeletal muscle loss should be considered. Further studies of sarcopenic impact on disease-related survival are required.