Serologic and molecular characteristics of hepatitis B virus infection in vaccinated schizophrenia patients in China

Previous studies have indicated that the patients with psychiatric illness were at higher risk of hepatitis B virus (HBV) infection. However, the efficacy of hepatitis B vaccine in schizophrenia patients remains unclear.

Between June 2014 and January 2015, 415 schizophrenia patients and 3,038 controls who had been routinely immunized as infants were recruited in the present study. Hepatitis B surface antigen (HBsAg), HBsAb, and HBV DNA were detected with commercial methods according to the manufacturer's protocol. A 600-bp region of the S gene (region nt236-nt835) was amplified by nested polymerase chain reaction (PCR). The genotypes of isolated HBV were identified using phylogenetic analysis by the neighbor-joining algorithm in the software MEGA version 4.1.

The seroprevalence of HBsAg in schizophrenia patients was 6.75%, which was significantly higher than 3.32% measured in controls. HBsAg prevalence was 7.94% in male schizophrenia patients and 5.47% in female schizophrenia patients, while it was only 4.04% in males and 2.08% in females in the control group. The HBsAb seroprevalence rate was 58.31% in schizophrenia patients and 59.94% in non-schizophrenia controls. Moreover, one HBV strain in the schizophrenia group presented I126S vaccine escape mutation (5.88%), while three HBV isolates showed Q129H, M133L, and G145R vaccine escape mutations in the control group (6.81%).

Schizophrenia patients are at higher risk for HBV infection, even those who had received routine immunization. Therefore, a booster HB vaccination targeted at schizophrenia patients should be considered in the future.