Effect of L-carnitine on quality of life in covert hepatic encephalopathy: a randomized, double-blind, placebo-controlled study
Eileen L. Yoon, Sang Bong Ahn, Dae Won Jun, Yong Kyun Cho, Do Seon Song, Jae Yoon Jeong, Hee Yeon Kim, Young Kul Jung, Myeong Jun Song, Sung Eun Kim, Hyoung Su Kim, Soung Won Jeong, Sang Gyune Kim, Tae Hee Lee
Abstract
BACKGROUND/AIMS: L-carnitine is potentially beneficial in patients with hepatic encephalopathy (HE). We aimed to evaluate the impact of L-carnitine on the quality of life and liver function in patients with liver cirrhosis and covert HE. METHODS: We conducted an investigator-initiated, prospective, multi-center, double- blind, randomized phase III trial in patients with covert HE. A total of 150 patients were randomized 1:1 to L-carnitine (2 g/day) or placebo for 24 weeks. Changes in quality of life and liver function were assessed at 6 months. The model for end-stage liver disease (MELD), the 36-Item Short Form Survey (SF-36), the psychometric hepatic encephalopathy score (PHES), and the Stroop Test were evaluated in all patients. RESULTS: The total SF-36 score significantly improved in the L-carnitine group after 24 weeks (difference: median, 2; interquartile range, 0 to 11; p < 0.001); however, these values were comparable between the two groups. Furthermore, there was a significant ordinal improvement in PHES scores among patients with minimal HE who were in the L-carnitine group (p = 0.007). Changes in the total carnitine level also positively correlated with improvements in the Stroop test in the L-carnitine group (color test, r = 0.3; word test, r = 0.4; inhibition test, r = 0.5; inhibition/switching test, r = 0.3; all p < 0.05). Nevertheless, the MELD scores at week 24 did not differ between the groups. CONCLUSION: Twenty-four weeks of L-carnitine supplementation was safe but ineffective in improving quality of life and liver function.