Does Prior Bariatric Surgery Predispose to Acetaminophen-Related Acute Liver Failure?

Background: Prior small studies have suggested that patients with prior metabolic bariatric surgery (MBS) may have increased susceptibility to acetaminophen (APAP) related acute liver failure/acute liver injury (ALF/ALI). This study compares the presentation, etiology, and outcome of adult ALI/ALF patients who were enrolled in a prospective registry study with prior bariatric surgery to those without.

Methods: Among 3,364 ALF/ALI subjects in the Acute Liver Failure Study Group (ALFSG) registry enrolled between January 1998 and August 2019, 85 (2.3%) reported prior MBS. On review, 6 cases were deemed not ALF and excluded from the analysis.

Results: Among the 79 MBS ALF/ ALI subjects, 95% were female and 86% were white. Etiology included APAP-related ALF/ALI in 78.5% of the MBS group vs 49.3% in the non-MBS group (p<0.001). The proportion of patients with MBS increased from 1.6% (1998-2008) to 3.4% in the later years (2009-2019) (p<0.001). There were proportionately more unintentional overdoses in the MBS cohort (71% vs 52%, p<0.001) with smaller median total APAP dose ingestion (6500 mg vs 12000 mg, p=0.009). Although MBS patients had more severe encephalopathy at presentation, overall, 21-day and transplant-free survival between the groups were similar.

Conclusions: ALF/ ALI is more frequent in MBS patients than in the general population. APAP toxicity is the most common cause in MBS patients but not the only diagnosis observed. MBS may predispose to severe unintentional APAP liver injury at lower doses. Both MBS patients and providers should be aware regarding this potential risk of increased susceptibility to APAP hepatotoxicity.