H. pylori-linked stomach ulcers triple dementia risk in Korea: study

A recent study reveals that the very bacteria that plague two-thirds of the world’s population—Helicobacter pylori, or H. pylori for short—might be eroding the minds of its victims, leading them to a heightened risk of dementia.

Published in the international journal GeroScience, recent research by Korean scientists has uncovered a new link between H. pylori-induced stomach ulcers—a pernicious bacterium behind inflammation, peptic ulcers, and even stomach cancer, especially prevalent in East Asia—and neurological decline. 

Kang Dong-woo, lead author and professor of psychiatry at the Catholic University of Korea St. Mary’s Hospital warned that “traditional Korean diets rich in fermented and spicy foods could be aggravating H. pylori infections,” a concern magnified among older Koreans with notably high infection rates.

The spiral-shaped bacterium, once it infiltrates the body through saliva, vomit, or stool, burrows into the stomach lining with its tail-like flagella. From there, it can cross the blood-brain barrier, potentially provoking neuroinflammation and disrupting the deposition of amyloid-beta and tau proteins—hallmarks of Alzheimer’s disease. Moreover, H. pylori-induced ulcers can hinder the absorption of essential nutrients for brain health and disturb the gut microbiome, further compounding the risk of dementia.

Professor Kang, alongside corresponding author Professor Lim Hyun-kook from the Catholic Dementia and Cognitive Impairment Center at Yeouido St. Mary’s Hospital, analyzed dementia risk among 47,628 participants aged 55 to 79 in the National Health Insurance Service database, comparing those who received H. pylori eradication therapy with those who didn't.

The analysis revealed that individuals with peptic ulcers face roughly a threefold increase in dementia risk over five and 10-year periods compared to healthy controls. This elevated risk persists even when accounting for common dementia risk factors such as hypertension, diabetes, ischemic heart disease, and hyperlipidemia. Notably, the data highlights a sharp rise in dementia risk, particularly Alzheimer's disease, among those in their 60s and 70s.

Previous research had already shown that eradicating H. pylori cuts the risk of gastric cancer. But the latest analysis dove deeper, pitting the risk of dementia in those who received early eradication therapy—within six months of a gastric ulcer diagnosis—against those who faced delayed treatment, waiting over a year. The results show that dementia risk was more than doubled in the delayed treatment group compared to those who received prompt intervention.

The study showed that early eradication of H. pylori was linked to a significantly reduced risk of dementia, suggesting that this gut bacterium could be a crucial target for protecting brain health. “Recent advances in diagnostic technology now enable precise infection identification, making early diagnosis and prompt treatment critical not just for gut health, but for brain health as well,” Professor Kang said.

H. pylori infections, often asymptomatic and affecting 50 to 60 percent of adults in Korea, are now linked to a disturbing turn.  To mitigate infection risk, experts advise eating stomach-friendly foods like cabbage, broccoli, and apples while steering clear of tobacco, alcohol, and overeating. Effective H. pylori treatment typically involves antibiotics and acid suppressants, and it’s crucial to ensure complete eradication of the bacteria due to its potential for recurrence. 

According to Professor Kang, this study is an early-phase investigation to examine the impact of peptic ulcer disease and H. pylori eradication treatment on dementia risk, and  further research is still necessary to fully understand this connection.

Professor Lim also stressed the urgency for ongoing research. “With the intricate connection between digestive and neurodegenerative diseases, we need to understand how gastrointestinal infections contribute to dementia,” he said. “This study is just the beginning.” 

The full study detailing these findings has been published in the latest issue of GeroScience.