Incident Dementia in Elderly Patients with Nonalcoholic Fatty Liver Disease in Germany

Abstract

Dementia and NAFLD are two frequent conditions that share underlying risk factors mainly in the realm of metabolic disease. Additionally, an association between NAFLD and brain aging has been proposed. Therefore, we investigated the hypothesis if NAFLD is an independent risk factor for emerging dementia. In this population-based cohort study, elderly patients (≥ 65 years) with NAFLD diagnosed between 2000 and 2015 were matched 1:1 to a cohort without NAFLD based on ICD-10 coding in the Disease Analyzer database. Matching criteria were age, sex, physician, index year, and co-diagnoses associated with dementia. The primary outcomes of this study were all-cause dementia diagnoses, the incidence of vascular dementia, and antidementive drug prescription. A total of 22,317 patients with NAFLD were matched to 22,317 patients without NAFLD. Within 10 years of the index date, 16.0% of patients with NAFLD and 15.6% of the patients without NAFLD were diagnosed with dementia. On Cox regression analysis, there is no association between NAFLD and the incidence of all-cause dementia (HR 0.97, 95% CI 0.92-1.04), vascular dementia (HR 0.89, 95% CI 0.78-1.02), or the new prescription of antidementive therapy (HR 0.87, 95% CI 0.76-1.01). In sensitivity analyses, there was no association between NAFLD and dementia in different age-groups as well as men or women. In conclusion, in this database study of elderly patients coded with NAFLD no independent association with incident dementia was detected. Risk assessment regarding dementia in patients with NAFLD should be carried out in the same way as for metabolic burdened patients.

Non-alcoholic Fatty Liver Disease and Longitudinal Cognitive Changes in Middle-Aged and Elderly Adults

“…In a 3-year follow-up study, Elliott and colleagues demonstrated that patients with NAFLD had faster cognitive decline compared to the general population (11). However, other studies have failed to demonstrate such a relationship (15,16). It remains open to question whether the relationship is an epiphenomenon.…”

“…A population with NAFLD were more likely to have impaired cognitive performance as compared with a healthy population (11)(12)(13)(14). However, most of the previous studies were crosssectional, which cannot assess the long-term effect of NAFLD on cognitive function (15,16). In addition, it was also unexplored whether the effect of NAFLD on subsequent cognitive impairment is modified by age, gender and carotid stenosis.…”

Non-alcoholic fatty liver disease does not increase dementia risk although histology data might improve risk prediction

“…One recent study found no increased risk of dementia in elderly patients with NAFLD, which corroborates with our results. 23 Apart from this, limited clinical studies examining cognitive functioning in NAFLD patients have provided varying and conflicting results, [6] , [7] , [8] , 10 discrepancies that might be as a result of methodological differences ( e.g. use of different cognitive tests and the mean ages of the study population).…”

Cognitive Dysfunction in Non-Alcoholic Fatty Liver Disease—Current Knowledge, Mechanisms and Perspectives

“…Another population-based study found that physically frail NAFLD patients with high risk of liver fibrosis were at a 5-fold increased risk of receiving a dementia diagnosis over a 8-year period, while physical frailty nor high risk of liver fibrosis were independent risk factors on their own [ 125 ]. Conversely, a third study found NAFLD not to be associated with a dementia diagnosis over a 10-year period in elderly patients ≥ 65 years [ 126 ]. In MRI brain studies, NAFLD was independently associated with reduced total brain volume, corresponding to 4.2 years of brain aging when compared with age-matched controls, as estimated by Weinstein et al [ 114 , 117 ].…”