A SUPER common stomach bug carried by one in four people could travel to the brain to cause Alzheimer’s disease, a study has suggested.
Helicobacter pylori (H. pylori) are bacteria – a type of germ – which live in the sticky mucus that lines the stomach.
About 15 per cent of people with H. pylori will develop symptoms – they’re 11 per cent more likely to also suffer from Alzheimer’s, according to research
It can be passed from person to person, through uncooked food or water that’s tainted with the bacteria.
Roughly 40 per cent of Brits have H. pylori in their stomach, according to Guts UK, probably picked up when they were children.
For most, the common stomach bug won’t cause any health problems.
But about 15 per cent of people will get ulcers in the lining of their stomach or duodenum, the start of the small intestine.
Others might develop indigestion, gastritis or even stomach cancer.
Now, scientists say H. pylori could affect more than just the gut.
A team of McGill University researchers analysed the health data of over 4 million people Brits aged 50 and above between 1988 and 2019.
The study – published in the journal Alzheimer’s & Dementia – found that people who experienced symptoms from an H. pylori infection were 11 per cent more likely to develop Alzheimer’s disease, the most common form of dementia.
The risk of developing the brain robbing disease was highest between seven and 10 years after the onset of the infection, with sufferers 24 per cent more likely to have Alzheimer’s.
Scientists said they couldn’t prove that an H. pylori infection is definitely the cause of an increased risk of Alzheimer’s.
But they had speculated that the bug might travel to the brain, leading to inflammation and loss of brain cells.
“A link between H. pyloris and the central nervous system has been proposed,” the study authors wrote.
“H. pyloris can access the brain via the oral-nasal-olfactory axis or by infected circulating monocytes through a disrupted blood-brain-barrier, potentially leading to neuroinflammation, neuronal damage, and neurodegeneration.”
The bacteria might also disrupt the gut microbiome, researchers suggested, leading to the overproduction of amyloid – the sticky protein that’s present in the brains of Alzheimer’s patients.
Finally, the McGill team suggested that damage to the gut caused by a chronic H. pyloris infection “could affect the absorption of vitamin B12 and iron, a deficit of which is associated with dementia”.
“The study opens avenues for future research, particularly exploring whether eradicating this bacterium could effectively prevent Alzheimer’s disease in some people,” McGill’s press release stated.
The research team estimated that eradicating the bug could prevent about 200,000 cases of Alzheiemer’s globally each year.
Dr Paul Brassard, the study’s senior author and a Professor in McGill’s Department of Medicine, said: “We hope the findings from this investigation will provide insight on the potential role of H. pylori in dementia in order to inform the development of prevention strategies, such as individualized eradication programs, to reduce infections at the population level.”
“Given the global ageing population, dementia numbers are expected to triple in the next 40 years. However, there remains a lack of effective treatment options for this disease.”
There are currently around 900,000 people with dementia in the UK, with number to rise to 1.6 million people by 2040, according to Alzheimer’s Society.
About six in 10 dementia sufferers have Alzheimer’s, according to Alzheimer’s Research UK.
People with the brain robbing disease will experience a build-up of two proteins, called amyloid and tau.
Research suggests that the build-up of these proteins damage more and more brain cells over time, affecting how our brains work and leading to the symptoms of Alzheimer’s.
What are the signs and symptoms of Alzheimers?
While there are common symptoms, every person diagnosed with Alzheimer’s is unique and will likely experience the disease differently.
But, for most, the earliest sign is problems with memory.
As the disease progresses a person might:
lose common items including keys and glasses around the house
struggle to find the word they are looking for in conversation
forget recent conversations or events
get lost in a familiar place, or while on a familiar journey
forget important anniversaries, birthdays or appointments
Though memory problems are the most common, there are other signs a person may be struggling with dementia.
They include:
speech problems – a person may struggle to follow a conversation or find they are often repeating themselves
problems judging distance, navigating stairs or parking the car
difficulties making decisions and solving problems
losing track of the day or date