Influence of hepatitis C virus on neurocognitive function in patients free from other risk factors: validation from therapeutic outcomes.

BACKGROUND AND AIMS: Mild neurocognitive dysfunction and altered cerebral proton magnetic resonance spectroscopy ((1) H-MRS) have been demonstrated in patients with chronic hepatitis C (CHC). This longitudinal study aimed to quantify these abnormalities in a cohort of patients free from correlated risk factors and determine whether treatment-induced viral clearance abolished these abnormalities.

METHODS: Treatment-naïve, non-cirrhotic patients with CHC, rigorously screened and excluded for other causes of impaired neurocognition, underwent neurocognitive testing, (1) H-MRS and evaluation for quality of life (QOL), mood and fatigue, before and 6 months after the completion of antiviral therapy. A comparison group of healthy controls was similarly assessed at baseline and 1 year later.

RESULTS: Post-treatment results in 40 patients with CHC [31 sustained virological responders, hepatitis C virus (HCV)-R and 9 non-responders, HCV-NR] were compared with their pretreatment results, and with the baseline and follow-up assessments of 39 healthy controls. Before receiving treatment, patients had impaired learning efficiency, poorer QOL and higher fatigue scores compared with the controls. Viral clearance was associated with a significant albeit small improvement in the QOL score that did not reach control levels. Cerebral (1) H-MRS demonstrated a lower N-acetyl aspartate/creatine (CRE) ratio in the globus pallidus (GP) of patients with hepatitis C, which was unchanged with viral clearance. The GP choline/CRE ratio increased in HCV-R following treatment, without a correlation with cognitive measures.

CONCLUSIONS: The hepatitis C virus has a measurable effect on CNS integrity in patients screened for other medical and/or psychiatric comorbidities. Viral clearance has not been demonstrated to abolish these abnormalities.