Jun 10, 2013
Insufficient serum levels of vitamin D, which ebb and flow with sun exposure, are associated with high levels of hepatitis B virus (HBV) replication in treatment-naive people who suffer from chronic infection.
Harald Farnik, from the Medizinische Klinik 1, Klinikum der Johann Wolfgang Goethe-Universität Frankfurt, Germany, and colleagues report the results of their study in an article published online May 22 in Hepatology.
HBV infection remains one of the most significant infectious diseases worldwide. According to the World Health Organization, 2 billion people worldwide have been infected with HBV, and roughly 600,000 die each year. Without antiviral therapy, the virus can attack the liver, and chronic infections progress to liver disease and cirrhosis. An emerging body of evidence has shown that vitamin D plays a role in inflammatory and metabolic liver diseases and that vitamin D can have a therapeutic effect for patients with tuberculosis. Although previous research has failed to demonstrate a correlation between hepatitis C viral load and circulating vitamin D levels, Dr. Farnik and colleagues sought to characterize the relationship between vitamin D metabolism and chronic hepatitis B.
They analyzed serum samples from treatment-naive patients with chronic hepatitis who visited the outpatient liver clinic of the Johann Wolfgang Goethe University Hospital in Frankfurt, Germany from January 2009 to December 2012. Two hundred and three patients were enrolled in the study. Every 3 HBV-infected patients enrolled in the study were randomly matched, according to age and sex, with 2 HCV-infected patients. Sixty-nine of the patients had severe vitamin D deficiency (25(OH)D3 levels < 10 ng/mL), 95 had vitamin D insufficiency (25(OH)D3 ≥ 10 ng/mL and < 20 ng/mL), and 39 had normal vitamin D levels (25(OH)D3 ≥ 20 ng/mL), Dr. Farnik and colleagues write.
"25(OH)D3 and HBV DNA serum levels showed a significant, inverse correlation (P=0.0003)," the authors write. "In both uni- and multivariate analyses, HBV DNA was the strongest determinant of low 25(OH)D3 serum concentration in our cohort (P=0.0007 and P=0.000048), respectively.
Additional studies will be needed to establish a causal relationship between vitamin D metabolism and HBV replication, the researchers write, as well as to explore the effect of adding supplemental vitamin D to existing therapies to improve the durability of treatment.
"In conclusion, we demonstrate a significant association between low 25(OH)D3 serum levels and high levels of HBV replication in chronically infected patients," they authors write. "Future studies to evaluate a therapeutic value of vitamin D and its analogs in HBV infection may be justified."
The authors have disclosed no relevant financial relationships.
Hepatology. Published online May 22, 2013. Abstract