Is Liver Disease a New Risk Factor for Dementia?

Non-alcoholic Fatty liver Disease (NAFLD) is associated with an increased risk of dementia and coexisting heart disease or strokeNew research shows.

Researchers analyzed data from nearly 3,000 older people diagnosed with NAFLD and compared it to a large group of matching peers without NAFLD.

At the end of the approximately 5-year follow-up period, 5% of NAFLD participants were diagnosed with dementia, while 4.6% of non-NAFLD participants were diagnosed with dementia.However, after adjustment Cardiovascular risk factorsPatients with NAFLD had a 38% higher incidence of dementia and a 44% higher incidence of dementia overall. Vascular dementia..

“We found that NAFLD, a fatty liver accumulation in the liver, is associated with an increased risk of dementia, especially if the patient has both NAFLD and heart disease,” said lead author Ying. Shang, PhD, Medicine, Karolinska Institute, Sweden said Medscape Medical News..

“This study calls for early cognitive testing of patients with NAFLD, especially those with comorbid cardiovascular disease, and early and more targeted treatment of NAFLD and its comorbid cardiovascular disease reduces the risk of dementia. We are emphasizing the possibility of doing so, “Shang said.

The survey results are Published online July 13 Neurology..

Independent risk factor?

“NAFLD is metabolic syndromeAnd metabolic disorders have been shown to be a well-known risk factor for dementia, “Shang said.

“It’s unclear if NAFLD contributes to dementia independently of these factors,” she said, although several other factors in metabolic syndrome are associated with an increased risk of dementia. ..

In addition, attention and memory problems have been reported in patients with NAFLD, suggesting a link between NAFLD and cognitive impairment.However, previous studies investigating this association said, “Most of them Mild cognitive impairment With a cross-cutting design, “the researchers write.

“25% of adults have NAFLD worldwide, and given the aging population, it’s important to understand whether NAFLD is associated with dementia independently of this metabolic disorder,” Shang said. Mr. says.

The researchers surveyed the Swedish National Patient Enrollment from 1987 to 2016 and identified 2898 individuals with NAFLD (mean age 70 years, 55.1% female). All were consistent with 28,357 disease-free individuals who acted as controls, depending on age, gender, and place of residence at the time of diagnosis.

Patients and controls were followed with a median of 5.5 and 5.6 years, respectively.

Patients with NAFLD have metabolic disorders, comorbid cardiovascular disease, and depression Compared to the matched control group (all) Ps <.001).

Vascular route?

During the follow-up period, 5% of the NAFLD group and 4.6% of the control group were diagnosed with dementia. The adjusted hazard ratio (aHR) for the development of dementia in the NAFLD and control groups was 1.86 (95% CI, 1.55-2.25).

The association between NAFLD and dementia weakened after adjusting for metabolic disorders (aHR, 1.64; 95% CI, 1.29-2.07) and further decreased after adjusting for depression, stroke, and HD, but statistically. Remained significant (aHR, 1.3; 95% CI, 1.1-1.72).

Patients with NAFLD had a higher incidence of both dementia and vascular dementia, but not a higher incidence than the control group. Alzheimer’s disease (advertisement). The coexistence of NAFLD and either heart disease (HD) or stroke “has an increased risk of dementia,” the researchers write.

The 5-year cumulative incidence of all-causal dementia was also higher in patients with NAFLD than in those without NAFLD (3.6% vs. 2.05, respectively).

When researchers compared the NAFLD group to members of a control group who did not have NAFLD, HD, or stroke, they found that patients with any of these disorders had a higher incidence of dementia.

The two disorders doubled the risk of dementia (aHR, 2.00; 95% CI, 1.52-2.62). Researchers say that co-existing NAFLD and “specific constellations” of stroke had the highest incidence of dementia.

“This study provides Class II evidence that NAFLD is associated with accidental vascular and non-vascular dementia,” the researchers write.

“We found that NAFLD is associated with dementia, especially vascular dementia, which indicates that NAFLD can affect cognition through vascular pathways.” Shang said.

In addition, patients with both NAFLD and HD or stroke have a higher risk of dementia, “further suggesting a vascular pathway that connects NAFLD to cognition,” she said.

“Toxic metabolites produced in the injured liver can cross the blood-brain barrier and cause neuroinflammation of the brain. So, in summary, NAFLD can have a direct impact on cognition, It can be affected through cardiovascular disease, “Shang said.

Important steps

comment For Medscape Medical NewsJorn Schattenberg, MD, professor of medicine and director of the Metabolic Liver Research Program at the University School of Medicine in Mainz, Germany, hypothesized that the findings showing the highest aHR for vascular dementia were NAFLD. He said he would support it. And more likely Non-alcoholic steatohepatitis In inflammation of the liver, “affects extrahepatic outcomes — and liver inflammation is mechanically involved.”

In addition, the powerful effect size in the presence of HD “supports the notion of the incremental effect of risk factors on outcome,” said Schattenberg, who was not involved in the study.

NAFLD perceptions are “increasing, but still incomplete,” he said. Therefore, it is important to identify NAFLD in primary and secondary medicine. [and] It informs patients about their individual risks and empowers them to make informed changes. “

again, Medscape Medical NewsDr. Galito Weinstein, Ph.D., Principal Investigator, Faculty of Public Health, University of Haifa, Israel, said the study “adds additional support for the possible link between NAFLD and brain health in the elderly.” Was called “important”.

“Because of the limited ability to treat dementia after being diagnosed, identifying a treatable health condition prior to its onset is an important step towards preventing dementia,” he said in a study. Weinstein, who wasn’t, said.

In the early stages, NAFLD can be treated with lifestyle changes and medications, according to Weinstein.

No funding has been reported for research. Investigators and Weinstein report that there is no relevant financial relationship. Schattenberg has previously collaborated with researchers in the analysis of the Swedish register, but was not involved in the current study. He is also consulting with companies developing treatments or diagnostic tests for NAFLD.

Neurology. Published online on July 13, 2022. Overview

Batya Swift Yasgur MA, LSW is a freelance writer counseling in Teaneck, NJ. She regularly contributes to numerous medical publications, including Medscape and WebMD, including consumer health books and Behind the Burqa: Our Life in Afghanistan and How We Escape Freely (Memoirs of two brave Afghan sisters who told her about them).

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