The impact of chronic carrier of hepatitis B virus on liver function in a 7-day ultramarathon race

Background: Several changes in physiological characteristics occur during long-distance and 24-hour ultramarathons, including hyponatremia, skeletal muscle breakdown, plasma volume changes, iron depletion, anemia, and possible hepatic damage. The purpose of this study was to investigate the impact of hepatitis B virus (HBV) carrier status on liver function during multi-day races. Methods: This prospective study recruited 10 Taiwanese runners who were scheduled to participate in the 7-day 2008 Athens Ultramarathon Festival Race, and three of them were chronic carriers of HBV. Blood samples were collected before, during, and 3 days after the race, including alkaline phosphatase (ALP), albumin (ALB), total protein (TP) levels, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin (T-BIL). Results: Ten Taiwanese runners (40% female; average age 52.3 ± 7.9 years) who all planned to run in the race were recruited. Three runners were chronic carriers of HBV (HBV carrier), and all participants were anti-HCV antibody-negative and anti-hepatitis A virus (HAV) IgG-positive. There were no significant time-by-group effects on ALP, ALB, and TP levels, but the change over time effects were significant (p <0.001, p = 0.001 and p = 0.010, respectively). ALT, AST, and T-BIL increased significantly to markedly higher levels in the HBV carrier group compared to the non-carrier group (group effect p = 0.009, p = 0.004, and p = 0.05, respectively), and the time-by-group interaction was also significant for these liver function markers (p <0.001, p <0.001, and p = 0.001, respectively). Conclusion: Compared to their counterparts, runners who are HBV carriers had significantly greater increases in levels of ALT, AST, and T-BIL during a 7-day ultramarathon, indicating that the liver function of carriers is more highly impacted in these races.