Long-term effects of L-carnitine on hyperammonemia and hepatic encephalopathy in patients with liver cirrhosis: a multicenter retrospective study.

OBJECTIVE

Long-term efficacy data for L-carnitine in managing blood ammonia concentration (BAC) and preventing hepatic encephalopathy recurrence remain limited. This multicenter study examined the long-term effects of L-carnitine on BAC, hepatic encephalopathy-related events, and clinical outcomes in patients with liver cirrhosis.

METHODS

Of 444 patients who received L-carnitine between April 2012 and March 2021, we enrolled 242 patients with hyperammonemia or hepatic encephalopathy (median Child-Pugh score 9) in this retrospective study across four institutions.

RESULTS

Median BAC decreased from baseline 123 μg/dl to 95.5, 88, 83, 96, and 86 μg/dl at 12, 24, 48, 96, and 192 weeks, respectively (all P  < 0.05). BAC normalization occurred at a median of 100 days overall, but significantly faster at 63 days with initial doses more than 1500 mg/day versus 4.7 months with less than or equal to 1500 mg/day ( P  = 0.0034). Among 113 patients followed for 2 years pre- and posttreatment, hepatic encephalopathy-related hospitalizations decreased dramatically from 183 to 62 ( P  < 0.001). Cumulative hepatic encephalopathy-related event incidence at 6, 12, and 24 months was 15.5, 18.1, and 23.7%, respectively. Model for End-Stage Liver Disease scores improved significantly at 1 year ( P  = 0.0059). Multivariate analysis identified ascites, albumin-bilirubin score, and HCC as independent prognostic factors for survival. Only 2.1% of patients experienced mild, transient gastrointestinal adverse events (all grade 1).

CONCLUSION

Long-term L-carnitine administration effectively reduces BAC and hepatic encephalopathy-related hospitalizations with excellent safety. Higher initial doses (>1500 mg/day) achieve more rapid BAC normalization and should be considered for patients with significant hyperammonemia.