Organic cause of ‘brain fog’ in hepatitis C

The complainant of ‘brain fog’ commonly voiced by patients with chronic hepatitis C infection even in the absence of cirrhosis appears to have an organic cause, as reported at the annual Digestive Disease Week.

One strong possibility is that this brain fog results from a direct neurotoxic immunologic effect of the hepatitis C virus upon the CNS, according to one doctor of the University of Toronto.

Typical complaints of brain fog in patients with chronic hepatitis C involve forgetfulness, fatigue, difficulty in concentrating, and depression.

To learn whether patients who complain of brain fog have objective brain abnormalities, a doctor subjected 17 chronic hepatitis C patients to neuropsychological testing and proton magnetic resonance spectroscopy.

All had a recent liver biopsy that was negative for cirrhosis. The finding is significant because it eliminates subacute hepatic encephalopathy as a possible explanation for cognition problems.

None of the participants had a history of injection drug use, which could also affect cognition.

More than one-half of the patients had significant impairment in verbal learning efficiency as reflected in subpar performance on the Hopkins Verbal Learning Test.

This impairment, constituting objective evidence of brain fog, was unrelated to depressive symptoms or histologic liver fibrosis scores.

On magnetic resonance spectroscopy, increased levels of glutamine, glutamate, and choline were seen in white matter and to a lesser extent in the basal ganglia of patients with abnormal neuropsychological test findings.