L-carnitine decreases severity and type of fatigue induced by interferon-alpha in the treatment of patients with hepatitis C

Background: Hepatitis C virus (HCV) is one of the major agents of chronic hepatitis and liver disease worldwide. Infection with HCV leads to chronic hepatitis in about 80% of the cases. The most used treatment is based on interferon (IFN)-alpha, which is effective in less than 50% of patients; however, a high proportion of responders may relapse after interferon withdrawal. Fatigue is a common complaint in patients with liver disease. The aim of our study was to evaluate the efficacy of carnitine on IFN-induced fatigue in subjects with chronic hepatitis C.

Patients and methods: We studied 50 patients (30 males and 20 females) with chronic hepatitis C. Chronic hepatitis was diagnosed by determination of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels (at least 2-fold upper normal values for 1 year). Our study series was divided into two groups and matched as to number, age, sex, as well as grade and duration of disease. Group 1, composed of 25 patients, was treated with leucocytic IFN-alpha at a dosage of 3 million IU thrice a week; group 2 (25 patients) was treated with the same protocol as group 1, but was also administered carnitine 2 g per os daily. Patients' response was evaluated on the basis of serum levels of AST and ALT as well as liver functions; fatigue was evaluated by Wessely and Powell scores. All patients studied were tested before treatment and then 1, 3 and 6 months after the beginning of IFN administration.

Results: The difference of physical fatigue between the two groups after 1 month of therapy was significant (p < 0.01) for patients treated with carnitine. This significance continued at the end of month 3 (p < 0.01). With reference to mental fatigue, the comparison between the two groups showed a significant difference for group 2 after 1 month (p < 0.01). Finally, with respect to the fatigue severity, the comparison between the two groups showed that after 1 and 3 months of therapy, fatigue was significantly less severe in group 2 than group 1 (p < 0.0005).

Conclusions: If we take into account baseline values of mental and physical fatigue as well as the severity of this symptom in our study series, one observes that therapy with IFN alone induces fatigue in the majority of cases after 1 and 3 months, while at month 6, the values decrease. In contrast, patients treated with IFN + carnitine show a marked and early significant reduction of fatigue levels. These data suggest that the greater energetic substrate utilised by group 2 patients may in some way provide a better response of the patients to this side-effect. Abnormalities of neurotransmission concerning serotonine seem involved in the genesis of depression and fatigue. In addition, depression and fatigue commonly occur together, and the former is the most commonly observed symptom in patients with chronic fatigue syndrome.