Hepatitis C virus positivity linked to schizophrenia development

Hepatitis C virus (HCV) positivity is associated with development of schizophrenia, according to a study recently published in the Journal of Psychiatry & Neuroscience.

Jur-Shan Cheng, Ph.D., from Chang Gung University in Taoyuan, Taiwan, and colleagues conducted a nationwide study using the Taiwan National Health Insurance Research Database from 2003 to 2012 to examine the potential association between HCV infection and schizophrenia. Three propensity score-matched cohorts were included from a total population of 19,298,735 individuals: 8,931 HCV-infected patients receiving interferon-based therapy for at least six months (HCV-treated); 17,862 individuals with HCV not receiving treatment (HCV-untreated); and 17,862 HCV-uninfected individuals. Overall, 82.81% of the total sample were aged 40 years or older.

The researchers found that the nine-year cumulative incidence of schizophrenia was highest in the HCV-untreated group (0.870%); a similar cumulative incidence of schizophrenia was seen for the HCV-treated and HCV-uninfected cohorts (0.251 and 0.118%, respectively). There was an independent association seen for HCV positivity with development of schizophrenia (hazard ratio, 3.469). The highest cumulative incidence of overall mortality was also seen in the HCV-untreated cohort (20.799%); the cumulative incidence of mortality did not differ significantly between the HCV-treated and HCV-uninfected cohorts (12.518 and 6.707%, respectively).

"In the era of direct-acting antivirals to eliminate HCV infection, anti-HCV therapy should be prescribed for all people infected with HCV to reduce the risk not only of hepatic complications, but also of extrahepatic complications, including schizophrenia," the authors write.