Find out the connection between liver disease and dementia. Plus, discover the consequences of dementia, as well as one of the best ways to treat NAFLD.
New research suggests that having non-alcoholic fatty liver disease may put you at a higher risk for developing dementia.
Many people with non-alcoholic fatty liver disease (NAFLD) don’t even know they have it! In the early stages, symptoms are generally non-existent. Yet, if left untreated, NAFLD can progress. This can cause you to feel tired and weak, potentially also leading to cirrhosis, which means the potential for internal bleeding, muscle wasting, and more. (1)
NAFLD and Dementia Risk
This study was published on August 9, 2022, in the journal Neurology. (2) It included 2,898 people aged 65 and up who had been diagnosed with NAFLD. These participants were then compared to 28,357 people without this liver disease, who served as the control.
Researchers followed all the individuals for around five and a half years. They learned that 5% of people with NAFLD were also diagnosed with dementia, compared to 4.6% of the control. This isn’t a huge difference but, after adjusting for comorbid cardiovascular conditions such as high blood pressure and diabetes, it was noted that there was a 38% higher risk of dementia for people with NAFLD.
The risk was the greatest for NAFLD patients under the age of 85 and for patients with co-occurring heart disease or who had experienced a stroke. If both NAFLD and cardiovascular disease were present, the rate of dementia increased two-fold, with rates being highest for individuals who had previously had a stroke.
This study also found that people with NAFLD had a 44% higher risk of having vascular dementia. This is a form of dementia caused when blood flow to the brain is inadequate, depriving it of the oxygen and nutrients it needs to function effectively. (3)
The Connection Between NAFLD and Dementia
How are NAFLD and dementia connected? The study pointed out that both conditions share common risk factors, including elevated blood pressure, obesity, and diabetes. However, it wasn’t totally clear how the two were associated.
Researchers suggested that the potential connections between NAFLD and dementia may include:
- cardiovascular disease in NAFLD patients causing damage to the blood vessels in the brain, thereby increasing the risk of vascular dementia
- insufficient brain amyloid clearance due to liver dysfunction combined with insulin resistance, with brain amyloid build-up being one of the hallmark signs of Alzheimer’s disease (4)
- toxic metabolites from the liver crossing the brain-blood barrier, leading to neuroinflammation in the brain
Part of what makes this connection so concerning is that many people don’t know they have NAFLD. Because it typically has no symptoms, it can exist without a person even knowing.
Consequences of Dementia
Dementia is characterized by deteriorating cognitive function. In simple terms, it affects a person’s ability to remember things, also impacting thought processing and comprehension.
People with dementia often face physical, psychological, financial, and social challenges—as do their caregivers and families.
Additionally, dementia is the seventh leading cause of death among all diseases combined. (5)
To be clear, this study did not find that NAFLD was a cause of dementia, only that there is some sort of link between the two conditions. That said, the benefits of treating NAFLD may extend to dementia since they share many of the same risk factors.
One of the best ways to treat NAFLD is to lose weight gradually (trying to drop excess pounds too quickly can actually worsen liver disease.)
Losing between 3% and 5% of your body weight can help reduce liver fat, while losing 7% to 10% of your body’s weight may offer even more benefits, such as reducing liver inflammation and fibrosis. (6)
While no medications are currently available for treating NAFLD, researchers continue to conduct studies in this area, potentially leading to future medicinal options.
Ways to Improve Cardiovascular Health
Since the risk of dementia was higher in NAFLD patients with co-occurring cardiovascular conditions, improving your heart health can be helpful as well.
UCI Health recommends: (7)
- getting regular physical exercise
- quitting smoking
- reducing stress
- losing weight
- eating foods good for the heart, such as salmon and guacamole—even chocolate, in moderation
- not overeating, which can cause blood to shift away from the heart to the digestive system, in addition to causing irregular and fast heart rhythms
Based on this new study, it’s possible that improving the health of your heart may reduce your dementia risk—particularly if you have NAFLD.
(1) Johns Hopkins Medicine. (n.d.). Nonalcoholic Fatty Liver Disease. Retrieved August 27, 2022, from https://www.hopkinsmedicine.org/health/conditions-and-diseases/nonalcoholic-fatty-liver-disease
(2) Shang, Y., Widman, L., Hagström, H. (2022, August 09). Nonalcoholic Fatty Liver Disease and Risk of Dementia: A Population-Based Cohort Study. Neurology. doi: https://doi.org/10.1212/WNL.0000000000200853
(3) Mayo Clinic. (2021, July 29). Vascular Dementia. Retrieved August 27, 2022, from https://www.mayoclinic.org/diseases-conditions/vascular-dementia/symptoms-causes/syc-20378793
(4) Alzheimer’s Association. (n.d.). Alzheimer’s Disease: What’s Sleep Got to Do with It? Retrieved August 27, 2022, from https://www.alz.org/media/documents/inbrief-sleep.pdf
(5) World Health Organization. (2021, September 2). Dementia. Retrieved August 27, 2022, from https://www.who.int/news-room/fact-sheets/detail/dementia
(6) National Institute of Diabetes and Digestive and Kidney Diseases. (2021, April). Treatment for NAFLD & NASH. Retrieved August 27, 2022, from https://www.niddk.nih.gov/health-information/liver-disease/nafld-nash/treatment
(7) UCI Health. (2017, February 09). 7 Powerful Ways You Can Strengthen Your Heart. Retrieved August 27, 2022, from https://www.ucihealth.org/blog/2017/02/how-to-strengthen-heart