Cognitive impairments in HCV infection: From pathogenesis to neuroimaging

Association of Cognitive Impairment With Chronic Viral Hepatitis Among Older Adults in Taiwan

OBJECTIVE

To evaluate the risk of cognitive impairment among patients with chronic viral hepatitis.

DESIGN

A cross-sectional study.

SETTING

Population-based.

PARTICIPANTS

Individuals 60 years or older were enrolled from the Taiwan Biobank database from 2012.

EXPOSURE

Hepatitis B virus and hepatitis C virus infections.

MEASUREMENT

Cognitive impairment was evaluated using the mini-mental state examination (MMSE). Logistic regression models were used to calculate odds ratios and 95% confidence intervals (CIs). The effects of APOE ε4 polymorphisms on the association between viral hepatitis and the risk of cognitive impairment were also investigated.

RESULTS

We recruited 912 participants with cognitive impairment and 22 869 participants without cognitive impairment. The adjusted odds ratio (aOR) for cognitive impairment was 1.38 (95% CI: 1.03-1.85, p = 0.033) among participants with hepatitis C virus infection and 1.14 (95% CI: 0.91-1.43, p = 0.257) among participants with hepatitis B virus infection. Participants with hepatitis C virus infection and without hepatitis B virus infection had a higher risk of cognitive impairment (aOR: 1.52, 95% CI: 1.13-2.04, p = 0.006). The MMSE subcategories most associated with hepatitis C virus infection were orientation and design copying. The association between hepatitis C virus infection and cognitive impairment was higher among participants with ε4 alleles of the APOE gene than among those without alleles (aOR: 2.18, 95% CI: 1.21-3.91, p = 0.009).

CONCLUSIONS

Our findings suggest that individuals 60 years or older with chronic hepatitis C virus infection are at increased risk of cognitive impairment.

Improved cognition after rifaximin treatment is associated with changes in intra- and inter-brain network functional connectivity

BACKGROUND

Rifaximin is a non-reabsorbable antibiotic which acts at gut level, and improves cognition and inflammatory parameters in minimal hepatic encephalopathy (MHE) patients, but not all patients show the same level of response. This study aims to assess brain activity, both within and between brain networks, following rifaximin treatment, considering the differences between response groups as well.

METHODS

Twenty-two healthy controls and 53 patients with cirrhosis (22 without and 31 with MHE, diagnosed by Psychometric Hepatic Encephalopathy Score, PHES) performed psychometric, attention and coordination tests, and blood inflammatory parameters were measured. Resting-state functional magnetic resonance imaging (fMRI) acquisitions were performed on controls and MHE patients. Eighteen MHE patients underwent a rifaximin treatment for 6 months, after which all measures were repeated. fMRI images were analysed and changes after treatment were assessed.

RESULTS

After rifaximin treatment, 13 patients improved their PHES score (Responder patients) while 5 did not (Non-responder patients). No significant decrease in blood ammonia was observed after rifaximin treatment, but there was a decrease in plasma inflammatory cytokines in responder patients. A global effect of rifaximin was detected on the sensorimotor and fronto-parietal networks. Responder patients showed a relative increase of thalamic network connectivity in comparison to non-responder patients. Before treatment, responder and non-responder patients showed connectivity differences in basal ganglia network. The connection of the sensorimotor and thalamic networks between them and with other networks suffered changes after treatment. These connections between networks mostly decreased after treatment. All changes and differences showed a significant level of correlation with the performance of psychometric tests and the blood levels of inflammatory biomarkers.

CONCLUSIONS

There was an improvement of the communication between executive, motor and attention-related brain areas, and their functional independence following rifaximin treatment. Patients who respond also show a less deteriorated connection involved in these functions before treatment. Results suggest that the improved inflammatory state of MHE patients, following rifaximin treatment would favour the observed changes in brain function and enhanced cognitive performance.

Cognitive Performance in Asymptomatic Elderly People with Hepatitis C: The Role of Education

BACKGROUND

Neurotropism of the hepatitis C virus (HCV) can be the source of subtle neuropsychological symptoms in non-cirrhotic patients. Age is a risk factor for cognitive impairment (CI). Thus, asymptomatic elderly people who carry HCV might be at a greater risk of CI. Education can influence test performance.

OBJECTIVES

(1) To verify whether elderly people with HCV performed poorer than controls on cognitive tests. (2) To analyze how education affects performance. (3) To verify whether the extent of the effect of education on performance depends on the group (HCV vs. controls) and the type of cognitive test.

METHODS

Asymptomatic HCV carriers older than 60 years (n = 41) were matched with 41 corresponding controls. All participants performed the following tests: Mini-Cog, Mini Mental State Examination, clock drawing test (CDT), and verbal fluency.

RESULTS

(1) There were no significant differences in cognitive performance between the two groups. (2) Higher education was always associated with better performance. (3) There was a significant group difference in the slopes of the regression lines between years of education and CDT performance. No differences were found for the other three tests.

CONCLUSION

Considering the scores on the CDT, the rate of improvement in performance when schooling increases is higher in HCV carriers.

Aspects of cognitive assessments and spectroscopic magnetic resonance imaging in people with chronic hepatitis C: a systematic review

Extrahepatic manifestations are common in people with hepatitis C virus (HCV). Cognitive changes are pointed out, but the mechanisms are still uncertain. The aim of this systematic review was to analyze studies involving spectroscopic magnetic resonance in people infected with HCV, which also included cognitive tests. The research occurred in six databases (Directory of Open Access Journals, Lilacs, Medcaribe, Medline, Scielo and ScienceDirect) and the selection of studies was carried out in two stages: search for titles and abstracts, then reading of the full articles, excluding those that did not meet the eligibility criteria. 12,888 titles and abstracts were selected, but only 6 articles were included in the review. Impairments in attention, concentration, speed of information processing, memory, verbal fluency and executive functions were identified as well as an increase in the Cho/Cr and mI/Cr ratios and a reduction in the NAA/Cr ratio in some included studies. Longitudinal studies, with more homogeneous samples and methods, as well as with better controlled confounding factors, are necessary to adequately identify the effect of HCV on the brain.

Seroprevalence of hepatitis C virus infection in children: A systematic review and meta-analysis

BACKGROUND AND AIMS

Estimates of paediatric hepatitis C virus (HCV) seroprevalence are needed to aid treatment scaling-up, screening and detection approach in this age range, with the ultimate goal of global HCV eradication. The aim of this study was to gather all of the available information on HCV seroprevalence in children all around the world.

METHODS

We searched PubMed, Scopus, Web of Science (WOS), Wiley and EBSCO databases for all studies evaluating HCV seroprevalence in children; however, studies examining seroprevalence in high-risk children or specific groups were excluded.

RESULTS

Only 20 articles with 48 963 people met our inclusion criteria, with an overall prevalence of 0.904% and a 95% confidence interval (CI) of 0.543 to 1.355. Seroprevalence was higher in research published prior to 2010 than in those published after 2010 (0.77% vs. 0.53%).

CONCLUSION

Few studies were conducted to assess the seroprevalence of HCV in children worldwide. However, the worldwide pooled seroprevalence of HCV in children in these studies is low (less than 1%).

DYT-PRKRA Mutation P222L Enhances PACT’s Stimulatory Activity on Type I Interferon Induction

DYT-PRKRA (dystonia 16 or DYT-PRKRA) is caused by mutations in the PRKRA gene that encodes PACT, the protein activator of interferon (IFN)-induced double-stranded (ds) RNA-activated protein kinase (PKR). PACT participates in several cellular pathways, of which its role as a PKR activator protein during integrated stress response (ISR) is the best characterized. Previously, we have established that the DYT-PRKRA mutations cause enhanced activation of PKR during ISR to sensitize DYT-PRKRA cells to apoptosis. In this study, we evaluate if the most prevalent substitution mutation reported in DYT-PRKRA patients alters PACT’s functional role in induction of type I IFNs via the retinoic acid-inducible gene I (RIG-I) signaling. Our results indicate that the P222L mutation augments PACT’s ability to induce IFN β in response to dsRNA and the basal expression of IFN β and IFN-stimulated genes (ISGs) is higher in DYT-PRKRA patient cells compared to cells from the unaffected controls. Additionally, IFN β and ISGs are also induced at higher levels in DYT-PRKRA cells in response to dsRNA. These results offer a new avenue for investigations directed towards understanding the underlying molecular pathomechanisms in DYT-PRKRA.

Neuropsychological effects of direct-acting antiviral treatment for Hepatitis C virus subjects: A systematic review

Direct-acting antivirals (DAAs) have been approved in recent years to treat patients infected by the Hepatitis C virus (HCV). The DAAs treatment is well tolerated and increases sustained virological responses, but there is no consensus about the neuropsychological functioning related to the treatment. This systematic review aims to provide an overview of the recent findings exploring the cognitive effects of DAAs treatment in patients with HCV. After a systematic search on PubMed, Embase, Scopus and LILACS, studies that assessed neuropsychological data related to DAAs treatment were included. We found nine articles, considering the inclusion and exclusion criteria. Three other manuscripts were included after searching for the references listed in the previously mentioned articles. We observed methodological heterogeneity in terms of neuropsychological tests used, cognitive domain explored and the sample characteristic presented between the studies. Studies presented data from HCV subjects monoinfected with or without cirrhosis, advanced liver disease and post-transplant patients; and HCV subjects coinfected with human immunodeficiency virus (HIV). Most results from the 12 studies that explored the effect of DAAs treatment in HCV subjects' neurocognitive functioning demonstrated cognitive improvement following treatment. In general, HCV and HCV/HIV subjects improved processing speed, verbal fluency and verbal/visual episodic memory. The DAAs treatment is effective for neurocognitive functioning in HCV monoinfected and coinfected subjects, with or without advanced liver disease, since neuropsychological scores increased after treatment. Further studies, however, are needed to confirm these findings.

Cognitive, neurological and psychiatric disorders occurring in Hepatitis C Virus infection

Chronic Hepatitis C is associated with many extrahepatic manifestations. Central nervous system is frequently involved, but the pathophysiological mechanisms are not fully understood. Local and systemic inflammation, ischemia, immune-mediated phenomena have been described in this context. Clinical manifestations include cognitive alterations, stroke, depression and demyelinating phenomena. It is unclear if cognitive deficits can be improved or resolved with viral eradication and to understand this, could have important therapeutical implications.

Neuroimaging and Cognitive Evidence for Combined HIV-Alcohol Effects on the Central Nervous System: A Review

Alcohol use disorder (AUD) among people living with HIV (PLWH) is a significant public health concern. Despite the advent of effective antiretroviral therapy, up to 50% of PLWH still experience worsened neurocognition, which comorbid AUD exacerbates. We report converging lines of neuroimaging and neuropsychological evidence linking comorbid HIV/AUD to dysfunction in brain regions linked to executive function, learning and memory, processing speed, and motor control, and consequently to impairment in daily life. The brain shrinkage, functional network alterations, and brain metabolite disruption seen in individuals with HIV/AUD have been attributed to several interacting pathways: viral proteins and EtOH are directly neurotoxic and exacerbate each other's neurotoxic effects; EtOH reduces antiretroviral adherence and increases viral replication; AUD and HIV both increase gut microbial translocation, promoting systemic inflammation and HIV transport into the brain by immune cells; and HIV may compound alcohol's damaging effects on the liver, further increasing inflammation. We additionally review the neurocognitive effects of aging, Hepatitis C coinfection, obesity, and cardiovascular disease, tobacco use, and nutritional deficiencies, all of which have been shown to compound cognitive changes in HIV, AUD, and in their comorbidity. Finally, we examine emerging questions in HIV/AUD research, including genetic and cognitive protective factors, the role of binge drinking in HIV/AUD-linked cognitive decline, and whether neurocognitive and brain functions normalize after drinking cessation.