Dear Editor,
The recently published study provides valuable insight into the long-term impact of bariatric surgery on patients with metabolic dysfunction-associated steatotic liver disease (MASLD) and cirrhosis [
1]. Utilizing a large population-based cohort and robust propensity score matching, the study highlights significant reductions in all-cause and liver-related mortality among patients undergoing bariatric surgery, particularly with laparoscopic approaches. However, while the findings are compelling, we believe the article warrants further investigation and refinement and requires further discussion in the following three areas.
First, despite its comprehensive design, the study is limited by its retrospective nature, which inherently limits causal inference. Reliance on administrative databases introduces potential misclassification bias, as diagnoses of MASLD and cirrhosis were based on International Classification of Diseases codes rather than standardized histopathological or imaging criteria. In addition, although propensity score matching was used to minimize confounding, residual confounding due to unmeasured variables - such as severity of liver fibrosis, nutritional status, and functional liver reserve - remains a concern. Future prospective studies using direct biomarkers of liver function and fibrosis (e.g., transient elastography, serum fibrosis indices) are needed to validate these findings.
Second, the observed benefits of bariatric surgery must be interpreted in light of the potential surgical risks, particularly in cirrhotic patients. While the study demonstrates a clear mortality benefit with laparoscopic surgery, it also indicates an increased all-cause mortality with open surgical approaches. This highlights the need for a nuanced risk-benefit assessment, as cirrhotic patients inherently face higher perioperative morbidity and mortality due to portal hypertension, coagulopathy and impaired wound healing. The study would have benefited from more detailed stratification of surgical complications, including rates of postoperative hepatic decompensation, infection, and nutritional deficiencies. Further research should focus on refining perioperative management strategies to reduce these risks.
Another important consideration is the generalizability of the study beyond the California-based cohort. The results are derived from a predominantly US population, and the applicability to other healthcare systems with different surgical expertise, postoperative care protocols, and patient demographics is unclear. In addition, racial and ethnic disparities in access to bariatric surgery have not been extensively discussed, despite growing evidence that socioeconomic factors significantly influence surgical candidacy and outcomes [
2,
3]. Investigating these disparities in future studies will be critical to ensuring equitable access to life-saving interventions for patients with MASLD.
Finally, while the study provides compelling evidence for the metabolic benefits of bariatric surgery in MASLD-associated cirrhosis, the underlying mechanisms remain to be fully elucidated. The improvements in liver-related outcomes may be mediated by weight loss-induced reductions in insulin resistance, systemic inflammation, and modulation of the gut-liver axis. However, the long-term metabolic and hepatoprotective effects of different bariatric procedures (e.g., sleeve gastrectomy vs. Roux-en-Y gastric bypass) have not been adequately compared. Randomized controlled trials with mechanistic endpoints, including changes in the hepatic transcriptome, bile acid metabolism, and microbiota composition, will be instrumental in elucidating these pathways.
In conclusion, this study advances our understanding of the role of bariatric surgery in MASLD-associated cirrhosis by demonstrating promising survival benefits while raising important questions regarding patient selection, perioperative risk reduction, and long-term metabolic effects. Future research should address these gaps through prospective, mechanistic, and multicenter investigations to optimize surgical strategies and improve outcomes for this growing patient population.