The stomach bug that could increase your risk of Alzheimer’s disease

Woman sitting on sofa. New research has linked a certain stomach bug with an increased risk of Alzheimer's disease. (Getty Images)
New research has linked a certain stomach bug with an increased risk of Alzheimer's disease. (Getty Images)

A common stomach bacteria found in two thirds of the world's population could be linked to a higher risk of Alzheimer’s disease, new research has suggested.

This time of year is often rife with winter viruses and sickness bugs and while a few days in bed is usually the outcome, new research has uncovered a potential link between one particular stomach bug and the risk of developing the most common type of dementia.

The study, published in Alzheimer's & Dementia: The Journal of the Alzheimer's Association, investigated whether the Helicobacter pylori (H. pylori) infection increased the risk of Alzheimer's disease in people aged 50 and older.

The prevalent infection can trigger indigestion, gastritis, ulcers and even stomach cancer.

A team of researchers from McGill University, in Canada, analysed health data of over four million people in the UK, aged 50 and above between 1988 and 2019.

The team found that people with symptomatic H. pylori infection had an 11% higher risk of developing Alzheimer's disease, with the risk rising to 24% 10 years post-infection.

Study authors believe the results could open avenues for future research, particularly exploring whether eradicating this bacterium could effectively prevent Alzheimer's disease in some people.

Alzheimer’s disease affects millions of people globally, with numbers expected to rise sharply as demographics shift, say researchers.

"Given the global ageing population, dementia numbers are expected to triple in the next 40 years," explains Dr Paul Brassard, the study’s senior author and a Professor in McGill’s department of medicine.

"However, there remains a lack of effective treatment options for this disease. 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 individualised eradication programs, to reduce infections at the population level."

Alzheimer's disease is the most common type of dementia. (Getty Images)
Alzheimer's disease is the most common type of dementia. (Getty Images)

What is Alzheimer's disease?

Alzheimer's disease is a type of dementia and is steadily increasing in the UK. It currently affects around 850,000 people, or one in every 14 people aged 65 and over.

The Alzheimer's Society estimates that the number of people with dementia will rise to 1.5 million by 2040.

Alzheimer's is the most common cause of dementia in the UK, which is the name for a group of symptoms associated with an ongoing decline of brain functioning, according to the NHS.

This can impact memory, thinking skills and other mental abilities.

Potential causes of Alzheimer's disease

While a specific cause isn't known for certain, risk factors are thought to include:

  • increasing age

  • family history of the condition

  • untreated depression

  • lifestyle factors associated with cardiovascular disease (affecting the heart or blood vessels)

It is most common in older people, affecting roughly one in 14 over 65 and one in six over 80. That said, around one in 20 experience it under 65, known as early or young-onset Alzheimer's disease.

As Alzheimer's is progressive, symptoms develop gradually over the years and become more severe.

Alzheimer's disease symptoms

The first sign of Alzheimer's is often minor memory problems, like forgetting about recent conversations or events, or the names of places and objects.

More developed and severe symptoms, according to the NHS, include:

  • confusion, disorientation and getting lost in familiar places

  • difficulty planning or making decisions

  • problems with speech and language

  • problems moving around without assistance or doing self-care tasks

  • personality changes, such as becoming aggressive, demanding and suspicious of others

  • hallucinations, low mood or anxiety

More than 850,000 people in the UK are living with Alzheimer's disease. (Getty Images)
More than 850,000 people in the UK are living with Alzheimer's disease. (Getty Images)

Can you prevent Alzheimer's disease?

A recent presentation at the American Heart Association’s Basic Cardiovascular Sciences Scientific Sessions 2023 said that a new vaccine that targets inflamed brain cells could be the key to preventing Alzheimer's.

There are also some lifestyle factors that are thought to reduce or delay the onset of dementia, as well as benefitting your overall physical and mental health. These include:

  • stopping smoking

  • cutting down alcohol

  • eating a healthy, balanced diet

  • maintaining a healthy weight

  • staying physically fit and mentally active

With memory problems often seen as a normal part of growing older, preventing people from recognising changes about themselves, signs can often be overlooked.

But an accurate and early diagnosis can help give you the best chance to prepare and plan for the future and receive treatment and support.

If you're worried about your memory or possible dementia, or have noticed symptoms in someone else, speak to a GP or encourage loved ones to.

While there's currently no cure, medicines can help to relieve symptoms and support is out there to help make your everyday life easier.

Some risk factors of dementia we can't change but others may be modifiable [Photo: Getty]
Some risk factors of dementia we can't change but others may be modifiable [Photo: Getty]

More information on Alzheimer's disease

For more information on Alzheimer's and treatment, visit the NHS website.

You can also see our useful guide on what other types of dementia there are.

Get support and advice by calling Alzheimer's Society on 0333 150 3456. Also, see full list of other info lines (which are fully accessible).

Alzheimer's disease: Read more

Watch: Student who went viral on TikTok alongside grandmother to become dementia specialist