Blood-Brain Barrier Damage, Psychiatric Impairment in HCV Infection and Alcohol Abuse

Alcohol use disorder (AUD) in patients with hepatitis C virus (HCV) infection is associated with increased symptoms of depression and anxiety compared with patients with HCV and no history of alcohol abuse, and the amount of alcohol consumption is positively associated with the severity of psychiatric symptoms, according to a longitudinal study published in Alcoholism Clinical & Experimental Research.

HCV infection and AUD are both associated with neuropathogenic effects as well as impairments in mood and cognition, but the mechanisms by which these conditions negatively affect brain function remain unknown. In addition, HCV infection and AUD both adversely affect the immune system, resulting in alterations in immune cell signaling and inflammatory processes. Thus, researchers investigated the effect of comorbid AUD on inflammatory mediators and psychiatric symptom severities in 42 adults with HCV and compared them with 13 adults with HCV and no history of alcohol abuse. 

They found that comorbid AUD was associated with increased symptoms of depression and anxiety, higher levels of liver enzymes, and altered expression of inflammatory factors. In addition, alcohol consumption was positively correlated with the severity of psychiatric symptoms. Significant differences between the groups were found for interleukin (IL)-8 (P =.006), IL-10 (P =.03), and blood–brain barrier (BBB) damage (as measured by S100 calcium-binding protein B; P =.048), with increased levels in patients with AUD, which persisted over time despite reductions in alcohol use and no significant change in HCV viral load.

The authors concluded that “HCV and comorbid AUD are associated with greater psychiatric impairments, potentially resulting from increased inflammation, dysregulated cytokine expression, and compromised BBB function.” Thus, “[a]lcohol-induced BBB damage may increase the risk of neuropathological consequences within the context of chronic HCV infection.”

Reference

Loftis JM, Valerio J, Taylor J, et al. S100B and inflammatory cytokine levels in blood as potential markers of blood–brain barrier damage and psychiatric impairment in comorbid hepatitis C viral infection and alcohol use disorder [published online June 28, 2018]. Alcohol Clin Exp Res. doi: 10.1111/acer.13796