Feng Tian,1,2,* Huiying Pan,3,4,* Qi Wu,2 Dapeng Jiang2 

1Department of Pediatric Surgery, Suzhou Wujiang District Children’s Hospital, Suzhou, Jiangsu Province, People’s Republic of China; 2Department of Oncology (Ward 2), Shanghai Children’s Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China; 3Department of Obstetrics and Gynecology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China; 4Department of Obstetrics and Gynecology, Shanghai Key Laboratory of Embryo Original Diseases, Shanghai, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Dapeng Jiang, Department of Oncology (Ward 2), Shanghai Children’s Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China, Email jdp509@163.com

Objective: To investigate the relationship between sarcopenia susceptibility and cesarean section (CS) and to assess causality using Mendelian randomization (MR).
Methods: Data from 1,316 individuals aged from 20– 59 in National Health and Nutrition Examination Survey (NHANES) 2013– 2016 were included in the study. The association between sarcopenia and CS was investigated by adjusting for confounders using multivariable linear and logistic regression analysis. Two-sample bidirectional MR was employed to evaluate causal relationships. Genetic data associated with CS (n=462,933) and appendicular lean mass (ALM, n=450,243) were sourced from the largest genome-wide association studies (GWAS). The primary analytical method used was inverse variance-weighted (IVW).
Results: Based on the cross-sectional study, the number of CS was positively correlated with sarcopenia across all adjusted models, whereas no such association was observed with vaginal delivery (VD). Subgroup analyses indicated that these associations were primarily evident among premenopausal women. IVW-MR analysis revealed a significant association between sarcopenia and CS (OR=0.989, 95% CI: 0.984 to 0.994, P< 0.001), but there was no statistically causal link in reverse (OR=2.100, 95% CI: 0.012 to 364.040, P=0.779).
Conclusion: A significant positive correlation and potential causal relationship between sarcopenia susceptibility and CS were identified, which highlighted the need for increased attention to sarcopenia in women with a history or high likelihood of CS, including but not limited to muscle health assessments during prepartum and postpartum periods, along with necessary muscle-strengthening interventions.

Keywords: sarcopenia, cesarean section, menopause, gestational diabetes mellitus (GDM), NHANES