<p>Cognitive impairment after liver transplantation: residual hepatic encephalopathy or posttransplant encephalopathy?</p>

Abstract

Liver transplantation (LT) represents the definitive treatment for end-stage liver disease. Cognitive impairment following LT is frequent, referred to as postliver transplant encephalopathy (PLTE). LT removes the underlying chronic liver disease, and until recently hepatic encephalopathy (HE) was assumed to be fully reversible after LT. However, increasing evidence indicates that some degree of cognitive impairment may be present after LT. To which extent PLTE reflects cognitive impairment caused by residual HE (RHE) or the combined effect of other factors affecting brain function before, during, and after LT is not clarified. None of the available psychometric and neurophysiological tests used for detecting HE is shown to be able to distinguish between etiologies. The available, mostly retrospective, clinical studies indicate a high prevalence of abnormal psychometric tests after LT, and not all seem to recover completely. The patients with earlier HE show the most marked improvements, suggesting that the clinical picture of the early PLTE, in fact, represents RHE. Other early post-LT etiologies for PLTE comprise cerebral ischemia, critical illness encephalopathy, and immunosuppressive therapy. Late-onset etiologies comprise diabetes and hypertension, among others. PLTE regardless of etiology is a worrying issue and needs more attention in the form of mechanistic research, development of diagnostic/discriminative tools, and standardized prospective clinical studies.

Cognitive Function in Liver Transplant Recipients Who Survived More Than 6 Months

“…Liver transplant research has suggested that multiple factors related to transplant, including unresolved pretransplant hepatic encephalopathy, comorbidities, and immunosuppressant treatment, may be etiologically associated with posttransplant cognitive impairment, in addition to aging of recipients. 11,12 This study found that male recipients demonstrated lower scores on tests of memory than female recipients. While the sex difference in cognitive function has not been reported in the liver transplant population, 2 this pattern of sex difference on memory is congruent with widely published studies on memory, which demonstrated that females have higher levels of memory than males.…”

“…There is a lack of knowledge regarding the demographic and clinical characteristics of liver transplant recipients with cognitive impairment. 11 Such data may provide clues as to who is at higher risk of developing cognitive impairment posttransplantation. Recipients over the age of 65 years in this study had lower scores in global cognitive function and visuospatial/ executive function than those under the age of 65.…”

“…Recent studies have suggested that pretransplant hepatic encephalopathy may have less of an impact on long-term cognitive function (eg, a year after transplantation). 2,11 Rather, they have proposed that multiple factors, such as increasing age of recipients and immunosuppressant treatment, may contribute to long-term cognitive impairment in the population, in addition to pretransplant hepatic encephalopathy. 11,12 Examining the cognitive trajectory beyond early periods of transplantation and its relationship with self-management in this vulnerable population would inform the design of interventions to improve health outcomes for liver transplant recipients.…”

Subjective Cognition Reported by Caregivers Is Correlated With Objective Cognition in Liver Transplant Recipients

“…Pretransplant hepatic encephalopathy and alcoholrelated liver diseases are key risk factors for posttransplant cognitive impairment. (3,29) Hepatic encephalopathy affects visuospatial abilities, attention, and psychomotor speed, (30) and alcohol-related liver diseases affect memory and executive function. (31) In line with previous findings, this study demonstrates poorer subjective cognition in domains affected by hepatic encephalopathy (eg, ECog visuospatial abilities, planning, and divided attention) in LT recipients with pretransplant hepatic encephalopathy than in those without the condition.…”

Renormalization of Thalamic Sub-Regional Functional Connectivity Contributes to Improvement of Cognitive Function after Liver Transplantation in Cirrhotic Patients with Overt Hepatic Encephalopathy

“…HE, especially OHE, has adverse effects on the quality of life, cognitive function, and working ability [ 3 4 ]. Although LT is the most effective strategy to restore cognitive function, it is still debated whether cognition can be fully reversed after LT [ 5 6 ]. Moreover, increasing evidence indicates that OHE may be an important factor for residual cognitive deficits after LT [ 2 7 ].…”