Non-alcoholic fatty liver disease (NAFLD) may increase the risk of dementia, suggests a recent study from Sweden published in the journal Neurology. It further says that those with heart disease and stroke are particularly at risk.

Data from 2898 patients with NAFLD, aged ≥65 years, from the Swedish National Patient Register (NPR) between 1987 and 2016 was evaluated to investigate a possible association between NAFLD and risk of new-onset dementia. A total of 28,357 matched controls, without NAFLD, were also selected.

Over a follow-up period of 5.5 years (median), 145 (5%) NAFLD patients and 1291 (4.6%) patients without NAFLD developed dementia. The rate of dementia was 38% higher among NAFLD patients after adjusting for risk factors such as diabetes, hypertension, obesity (adjusted hazard ratio 1.38). None developed Alzheimer’s disease. The incidence of vascular dementia was 44% higher in the presence of NAFLD with aHR of 1.44. Co-existing heart disease increased the risk of dementia by 50% (aHR 1.50). The risk increased by 2.5 folds among patients with NAFLD and stroke (aHR 2.60).

This study has shown a link between NAFLD and all-cause dementia, mainly vascular dementia but not dementia due to Alzheimer’s disease. This relationship was particularly robust in patients with comorbid heart disease. This risk was independent of the cardiometabolic risk factors. NAFLD is increasing in prevalence globally. Since it is mostly asymptomatic, the diagnosis is often missed resulting in inaccurate estimation of the interrelationship, which according to the authors is a limitation of their study.

Reference

1. Shang Y, et al. Nonalcoholic fatty liver disease and risk of dementia: a population-based cohort study. Neurology. 2022 Jul 13:10.1212/WNL.0000000000200853. doi: 10.1212/WNL.0000000000200853