Risk of Liver Injury Associated with Chinese Herbal Products Containing Radix bupleuri in 639,779 Patients with Hepatitis B Virus Infection

BACKGROUND Chinese herbal products (CHPs) containing radix bupleuri are often prescribed for chronic hepatitis. There have been no epidemiological studies in populations with hepatitis B virus (HBV) infection. Our study was conducted to determine the association between the use of CHPs containing radix bupleuri and the risk of hospitalisation related to liver injury among HBV-infected patients in Taiwan. METHODS From a total of 639,779 patients with diagnoses related to HBV infection, we included hospitalised adult cases with a primary diagnosis of liver injury in the database of Taiwan's national health insurance during the period 1997-2004. Case-control and case-crossover designs were used to assess the risk of hospitalisation with conditional logistic regression models constructed and adjusted for 270 conventionally hepatotoxic drugs. Cumulative doses of these CHPs and radix bupleuri were assessed for any dose-response relationship. FINDINGS In total, we collected 1,080 cases fulfilled the inclusion criteria. In the case-control design, the adjusted odds ratio was 1.90 (95% confidence interval [CI]: 1.30 to 2.77). The risks from prescribing the CHPs Xiao-Chai-Hu-Tang and Long-Dan-Xie-Gan-Tang were significantly high, and dose-response relationships were found. The risk of adding each 19 gm dose of radix bupleuri was 2.19 (95% CI: 1.66 to 2.89). The results using the case-crossover design remained similar. CONCLUSIONS Prescribing Xiao-Chai-Hu-Tang, Long-Dan-Xie-Gan-Tang, or CHPs containing more than 19 gram of radix bupleuri in HBV-infected patients might increase their risks of liver injury. Further studies are indicated to corroborate the above findings.