The association of sarcopenic obesity with respiratory function outcomes in adults: a systematic review and meta-analysis

Sarcopenic obesity has been associated with various health conditions and mortality. Our objective was to systematically review and estimate the association between sarcopenic obesity and respiratory function outcomes. We searched EMBASE, MEDLINE, and Google Scholar for observational studies involving adults (≥ 18 years), defined sarcopenic obesity, and assessed respiratory outcomes in those with and without sarcopenic obesity. A random-effects meta-analysis was conducted for the outcomes of forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and the ratio of forced expiratory volume in 1 s to forced vital capacity (FEV1/FVC). Seven papers representing 173,677 participants were included. The risk of bias assessment using the JBI Critical Appraisal Checklist revealed that all studies had a low risk of bias. The meta-analysis included data from five studies, revealing a significant association between sarcopenic obesity and lower FVC (in L) (−0.77; 95% CI, −1.27, −0.26) and FEV1 (in L) (−0.84; 95% CI, −1.26, −0.42), both with high heterogeneity (I2 = 94%). Sarcopenic obesity was significantly associated with respiratory function outcome (FEV1) when obesity was assessed using fat mass % (−1.14; 95% CI, −1.21, −1.06), but not when using the body mass index (BMI). In conclusion, sarcopenic obesity was significantly associated with poorer respiratory function outcomes. Assessment of respiratory function may be desirable in those with sarcopenic obesity, especially in high-risk populations such as older adults.