Hepatitis C virus (HCV) is a major health burden in England (Public Health England, 2015). HCV treatment is a significant component in control of the disease but the neuropsychiatric side effects of the treatment have been associated with treatment interruption. We, and others, are studying how these side effects impact discontinuation rates, with particular interest in the cognitive side effects of treatment.
According to recent evidence (Monaco et al, 2015) the hepatitis C virus (HCV) associated neurocognitive disorder (HCV-AND) involves executive function, sustained attention, working memory, verbal learning and verbal recall. Several factors, such as alcohol misuse, substance abuse, interferon treatment and HCV itself have been identified as contributors to HCV-AND. Interestingly, changes in neuropsychological performance in HCV patients occurred independently of HCV genotype and stage of liver disease. The same review described results of studies looking at brain changes. These studies suggested that HCV infection is associated with brain metabolic alterations due to the presence of HCV replication in specific areas of the brain (in the frontal cortex, basal ganglia and subcortical white matter), as in agreement with previous results in HIV and HCV co-infected patients.
These findings are in line with the idea that HCV causes brain changes and activates mechanisms that increase the acceleration of cognitive impairment. Additionally, it seems that HCV and HIV are detected in the same brain areas. Despite the co-factors that contribute to cognitive dysfunction in HCV infection, the pathogenic role of the HCV virus in the brain is an issue of major importance to target treatment options.

Reference

Monaco, S., Mariotto, S., Ferrari, S., Calabrese, M., Zanusso, G., Gajofatto, A., … & Dammacco, F. (2015). Hepatitis C virus-associated neurocognitive and neuropsychiatric disorders: Advances in 2015. World journal of gastroenterology, 21(42), 11974.