Identifying patients at risk for postoperative pneumonia and preventing it in advance is crucial for improving the prognoses of patients undergoing surgery. This review aimed to interpret the predictive value of sarcopenia on postoperative pneumonia.

Science Citation Index Expanded (SCIE), Embase, Medline, and Cochrane Central Register of Controlled Trials were searched from inception to August 2nd, 2023 to retrieve eligible studies. The risk of bias was assessed by the Newcastle-Ottawa Scale (NOS). For each study, we computed the odds ratio (OR) and 95% confidence interval (CI) for postoperative pneumonia in patients with and without preoperative sarcopenia, and the I-squared (I²) test was employed to estimate heterogeneity.

The search identified 6530 studies, and 32 studies including 114,532 participants were analyzed in this review. In most of the studies included, the risk of bias was moderate. The most reported surgical site was the chest and abdomen, followed by the abdomen, chest, limbs and spine, and head and neck. Overall, patients with preoperative sarcopenia have a 2.62-fold increased risk of developing postoperative pneumonia compared to non-sarcopenic patients [OR 2.62 (I² = 67.5%, 95%CI 2.04–3.37). Subgroup analysis focusing on different surgical sites revealed that sarcopenia has the strongest predictive effect on postoperative pneumonia following abdominal surgery (OR 4.69, I² = 0, 95% CI 3.06–7.19). Subgroup analyses targeting different types of research revealed that sarcopenia has a stronger predictive effect on postoperative pneumonia in prospective studies (OR 5.84 vs. 2.22).

Our research findings indicate that preoperative sarcopenia significantly increases the risk of postoperative pneumonia. Future high-quality prospective studies and intervention studies are needed to validate the relationship between sarcopenia and postoperative pneumonia and improve patient outcomes.