Is there an association between non-alcoholic fatty liver disease and cognitive function? A systematic review

Abstract

Background Non-alcoholic fatty liver disease (NAFLD) is represented as the most common liver disease worldwide. NAFLD is associated with metabolic risk factors underpinned by insulin resistance, inflammation and endothelial dysfunction, leading to extrahepatic changes in central nervous diseases such as cognitive impairment, Alzheimer’s disease and dementia. The aim of the review is to explore the association between NAFLD and cognitive function. Methods Using the PRISMA guidelines, a systematic electronic literature search was conducted in four databases: MEDLINE, PsychINFO, Embase and CINAHL from inception until March 2021. Neuropsychological tests utilised within each study were grouped into relevant cognitive domains including ‘general cognition’, ‘reasoning’, ‘mental speed, attention and psychomotor speed’, ‘memory and learning’, ‘language’, ‘visuospatial perception’ and ‘ideas, abstraction, figural creations and mental flexibility’. Results Eleven observational studies that involved 7978 participants with a mean age of 51 years were included. Those with NAFLD had poor cognitive performance in three cognitive domains, including ‘general cognition’, ‘mental speed, attention and psychomotor speed’, and ‘ideas, abstraction, figural creations and mental flexibility’. Conclusion The observed results from the 11 included studies showed that NAFLD was associated with lower cognitive performance across several domains. However, studies conducted to date are limited to observational designs and are heterogeneous with varying diagnostic tools used to assess cognitive function. Trial registration PROSPERO Registration: CRD42020161640.

Risk of dementia or cognitive impairment in non-alcoholic fatty liver disease: A systematic review and meta-analysis

“…The conclusions drawn from the results of the data can also be verified from the results of previous research. A review (George et al, 2022 ) of 11 observational studies showed NAFLD to be associated with low cognitive ability across several domains, such as “general cognition,” “mental speed, attention, and psychomotor speed,” and “ideas, abstraction, figural creations, and mental flexibility.” In the study by Sang et al (Seo et al, 2016 ), 874 (19.5%) of 4,472 patients with confirmed NAFLD were diagnosed with cognitive impairment. However, the study failed to provide enough data to calculate the increased risk of cognitive impairment in relation to NAFLD.…”

“…Previous studies have found that NAFLD is associated with poorer cognitive function. Nonetheless, the studies conducted to date have been limited to an observational design and have demonstrated methodological heterogeneity, using various diagnostic tools to assess cognitive function (George et al, 2022 ). Meanwhile, systematic reviews and meta-analyses concerning the association between NAFLD and cognitive impairment or dementia are lacking.…”

Effects of Ornithine Aspartate and Empagliflozin on Memory Deficit Symptoms in Experimental Steatohepatitis

“…Приходько «Влияние орнитина аспартата и эмпаглифлозина на проявления мнестического дефицита при экспериментальном стеатогепатите» ке [5]. Развитие дефицита зрительнопространственной памяти у пациентов с различными стадиями НАЖБП было подтверждено в двух срезовых популяционных исследованиях и одном исследовании типа «случай-контроль» [4].…”

Linking Nonalcoholic Fatty Liver Disease and Brain Disease: Focusing on Bile Acid Signaling

“…Extensive evidence obtained in recent years has revealed that NAFLD could be linked to a lower cognitive performance [ 34 ], mood imbalances [ 35 ] (in particular, depression and anxiety), cerebrovascular alterations [ 36 ], and a low total cerebral volume [ 37 ]. When NAFLD develops, a number of pro-inflammatory cytokines and chemokines are released into the bloodstream, starting the coagulation cascade pathway and causing the endothelial dysfunction and cerebral atherosclerotic disease [ 38 , 39 , 40 , 41 ].…”