Flu vaccination linked to a 40 per cent reduction in risk of Alzheimer

Researchers have found a close link between the flu vaccination and a 40 per cent reduced risk of Alzheimer.

Focusing on Americans aged 65 and older, the study compared the risk of Alzheimer’s disease between patients with and without prior flu vaccination.

The research, conducted by The University of Texas at Austin , follows previous research from the university, that already found a possible link between the flu vaccine and a reduced risk of Alzheimer disease two years ago.

To collect the data needed, the researchers analysed the numbers of 935,887 flu-vaccinated patients and 935,887 non-vaccinated patients over the course of four years. During the appointments with the patients, 8.5 per cent of non-vaccinated patients developed Alzheimer’s disease against a 5.1 per cent of flu-vaccinated patients. 

The results of the research paper only covered a small part of the underlying mechanisms of Alzheimer’s disease and its connection with the flu vaccine, which leaves space for further research. 

One of the researchers, Dr Shoulz, stated that the reduction of  the risk of Alzheimer’s disease is not a specific effect of the flu vaccine.

He added “Instead, we believe that the immune system is complex, and some alterations, such as pneumonia, may activate it in a way that makes Alzheimer’s disease worse. But other things that activate the immune system may do so in a different way – one that protects from Alzheimer’s disease.

“Clearly, we have more to learn about how the immune system worsens or improves outcomes in this disease.”

“We found that the flu vaccination in older adults reduces the risk of developing Alzheimer’s disease for several years. The strength of this protective effect increased with the number of years that a person received an annual flu vaccine,” said Bukhbinder, the first author of the research.

“Future research should assess whether flu vaccination is also associated with the rate of symptom progression in patients who already have Alzheimer’s dementia,” he added. 

Following this finding that connect the flu vaccine to a reduced risk of Alzheimer’s disease, Dr Bukhbinder shared his interest in undertaking further research to understand whether a similar association exists between COVID-19 vaccination and Alzheimer.

Past studies have already showed a decreased risk of dementia associated with exposure to various vaccinations, such as polio, herpes and tetanus. 

Although this new case study used a large sample, studies with longer follow-up periods are desirable as the symptoms of Alzheimer only appear decades after the pathology begins.

Alzheimer affects six million people in the US and over 850,000 people in the UK, according to a 2019 study.

This means that one in every 14 people of the population aged 65 years and over are affected by the Alzheimer’s disease. According to the Alzheimer’s Society, people with Dementia will increase to 1.5 million people by 2040 in the UK alone. This growth in elderly people affected by Alzheimer is expected to be steady if no action is taken. 

Worldwide, numbers of people living with dementia are expected to double every 20 years. By 2050 the people with dementia will be 115 million against 36 million nowadays. The current estimated cost of dementia worldwide is £380 bn (US$604 billion).