Liver and vitamin B₁₂ parameters in patients with anorexia nervosa before and after short-term weight restoration.

Hepatic involvement in anorexia nervosa (AN) has been previously reported, but a link to elevated vitamin B concentrations, which can be a sign for liver damage, has not been thoroughly examined. We measured liver enzymes (alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase) and vitamin B parameters (total B, holotranscobalamin, methylmalonic acid) in the plasma of young female patients with acute AN (n=77) and after short-term weight restoration (n=58, median body mass increase=25%), in comparison to healthy control participants (n=63). For a comprehensive assessment of vitamin B status, the combined marker cB was calculated. In acute AN, activities of alanine aminotransferase and gamma-glutamyltransferase as well as holotranscobalamin concentrations were elevated, and alanine aminotransferase activities positively correlated with total B, holotranscobalamin and cB in patients with elevated liver enzyme activities. After weight restoration, alanine aminotransferase activities and holotranscobalamin concentrations were elevated, and cB increased above the level of the healthy control group. The present study provides further evidence for a hepatic involvement in acute AN in concert with vitamin B parameters and points to refeeding-associated alterations of liver and vitamin B parameters. Future studies should include non-invasive methods to characterize hepatic involvement and evaluate vitamin B status as a potential marker of liver damage/irritation.