Cognitive dysfunction in patients with non-alcoholic fatty liver disease

Aim. To investigate neurodynamic parameters as markers of cognitive impairment in non-alcoholic fatty liver disease (NAFLD). Materials and Methods. Here we enrolled forty patients with NAFLD diagnosed by liver ultrasound findings, the presence of obesity or dyslipidemia, and absence of other causes of hepatic steatosis (i.e., alcohol use, drug-induced liver injury, environmental toxins, nutritional or intestinal disorders, endocrine diseases, and monogenic conditions). The laboratory investigation included a complete blood count, comprehensive biochemical panel (bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gammaglutamyl transferase, lipid profile, glucose, creatinine, urea, total protein and protein fractions, and prothrombin index). The non-invasive Fibrosis-4 (FIB-4) index was used to assess fibrosis severity. Alcohol misuse was screened using the Alcohol Use Disorders Identification Test (AUDIT). To exclude hepatic encephalopathy, the Reitan number connection test was performed. All patients were also evaluated using the Mini- Mental State Examination (MMSE) to detect dementia and pre-dementia cognitive impairments. Cognitive functions were assessed using the Status PF software with a reaction registration adapter developed at Kemerovo State University. Neurodynamic parameters included the complex visual-motor reaction time and response to a moving object. The control group consisted of 30 healthy volunteers matched by age and sex. Results. Patients with NAFLD, even in the absence of significant fibrosis or biochemical markers of inflammation, demonstrated altered neurodynamic parameters compared to the control group, and inhibition processes in the central nervous system prevailed. Conclusion. Patients with NAFLD exhibit cognitive deficits not associated with hepatocellular injury or hepatic encephalopathy. Central nervous dysfunction in hepatic steatosis reflects the complex multifactorial pathogenesis of the underlying disease and warrants further investigation

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