Cognitive dysfunction in patients with chronic hepatitis C: a psychometric and magnetic resonance spectroscopic study

ABSTRACT

Patients with chronic hepatitis C virus [HCV] infection frequently describe neuropsychological symptoms and there is a growing body of literature on cerebral dysfunction occurring at an early stage of chronic HCV infection. The aim of the present study was to elucidate whether patients' subjective impression of cognitive impairment was accompanied by objective evidence of cerebral dysfunction. 12 Patients with chronic hepatitis C virus infection with compensated liver function were recruited from Ain-Shams university hospitals. Another 8 healthy controls matched for age and sex were recruited from available hospital staff or patients relatives. Patients with potential risk factors for cognitive impairment were excluded. All patients and controls underwent clinical assessment, laboratory test, abdominal ultrasound, neuropsychological assessment, digital electroencephalography [DEEG], brain MRI and MR spectroscopy [MRS]. DEEG of all 12 patients revealed normal background with well formed alpha waves with no focal or generalized slowing and no epileptic activity. Psychometric assessment revealed that attention and sustained attention was affected in 6 patients [50%], short term memory was affected in 4 patients [33.5%], psychomotor speed and learning ability was affected in 4 patients [33.5%] and immediate verbal and visual memories were affected in 6 patients [50%]. Depression was absent in all patients. The MRI brain of all patients revealed no abnormalities. On intermediate echo sequence of MRS, the HCV group showed significant decrease in N-acetylaspartate/creatine ratios [NAA/Cr ratio] in frontal white matter [P < 0.05]. Mild, statistically non significant, elevation of choline/creatine ratios predominantly in basal ganglionic [BG] region was noted on both short and intermediate echo sequences. On short echo sequence of MRS, the HCV group showed a mild, statistically non significant, increase in myoinositol/creatine in frontal white matter region as compared to controls. Thus, there is a suggested reduction of normal neurons and accentuation of gliosis in frontal white matter together with membrane degradation in BG in patients with hepatitis C virus infection. Agreement between psychometry and MRS revealed a significant agreement between decreased NAA/Cr and impaired attention and sustained attention, immediate verbal memory and immediate visual memory [P < 0.05]. HCV infection itself is associated with changes in the brain, even in the absence of hyperammonemia. Specifically, HCV-infected individuals may have deficits in cognitive functions such as attention, working memory, and speed of information processing. They also have abnormalities on magnetic resonance spectroscopy [MRS] that favor the organic explanation of the patients' mental symptoms