L-carnitine trends toward QOL, cognitive improvement in hepatic encephalitis

Though absolute differences did not emerge in the treatment of hepatic encephalopathy with L-carnitine, a presenter at the Digital International Liver Congress suggested the changes seen indicate more research with higher doses may be warranted.

“Twenty-four weeks of L-carnitine supplementation in covert hepatic encephalopathy patients did not improve quality of life,” Eileen Yoon, MD, PhD, of Sanggye Paik Hospital, Inje University College of Medicine, Seoul, South Korea, said during her presentation. “However, L-carnitine supplement stabilized liver function and supplement was positively correlated with improvement of cognitive function.”

Yoon and colleagues conducted a prospective, randomized, double-blind, placebo-controlled study in 13 clinics in South Korea in which they evaluated QOL using the 36-Item Short Form Survey (SF-36) in hepatic encephalopathy patients treated with 24 weeks of L-carnitine. Hepatic encephalopathy was defined as either West-Haven grade 1 or grade 0 with the Psychometric hepatic encephalopathy score (PHES) below –4.

The researchers screened 238 patients with cirrhosis between 2015 and 2017 in which they randomly assigned 150 patients with HE into a placebo or L-carnitine group. The mean age was 54 years and 64.8% were men. Most had chronic hepatitis B and 82.4% had Child-Pugh A cirrhosis. At 24 weeks of treatment, there were 51 patients in the placebo group and 58 patients in the L-carnitine group; per-protocol analysis included 32 people in the placebo group and 33 people in the L-carnitine group.

Although SF-36 levels were not significantly different between the placebo and treatment groups, the differences of SF-36 between the baseline and at 24 weeks of treatment did show improvement in the L-carnitine group (P = .001 for physical components; P = .01 for mental and P < .001 total).

Additionally, Yoon showed that the MELD scores between the two groups showed a positive correlation with L-carnitine treatment.

“The MELD scores ... were significantly different between the two groups. The MELD scores seem to improve with L-carnitine supplementation,” she said. “However, the absolute MELD scores were not different between the two groups at week 24.”

In looking at cognitive function with PHES, Yoon showed improvement in the L-carnitine group (P = 0.007).

“PHES scores showed significant tendency of improvement during subsequent visits,” she said.

The rate correct score of inhibition test among the Stroop Test at 24 weeks of treatment was higher in the L-carnitine group (P = .038), Yoon said. The gap of total carnitine level between baseline and week 24 were positively correlated with the improvement of rate correct scores of all four components in the Korean Stroop Test (r = 0.3 for Color Test; r = 0.4 for Word Test; r = 0.5 for Inhibition Test; r = 0.3 for Inhibition/Switching Test; all P values < .03) in the L-carnitine group.

“Interestingly, the change of total carnitine level were positively correlated with every ... test of the STROOP test,” Yoon said. “In conclusion, 2 g of L-carnitine was not enough. ... Higher dosage of L-carnitine supplement may be beneficial in the improvement of cognitive function.”