Researchers were surprised to find that the flu vaccine could offer protection against Alzheimer’s; it could reduce the chance of people over 65 being diagnosed with Alzheimer’s up to four years later by 40%.
Although it is still far too early to determine whether there are direct causal links between this vaccine and the potential onset of neurological conditions such as Alzheimer’s; in other words, it is not known whether the flu vaccine itself or something else is responsible for this protection against Alzheimer’s.
The research is certainly a promising advance that could point scientists in the direction of easily accessible treatments.
The flu vaccine offers modest protection against Alzheimer’s
In a peer-reviewed study, from Journal of Alzheimer’s Diseaseresearchers from UTHealth Houston in the US compared the incidence rate of the disease in patients with and without at least one flu shot in a nationwide sample of US adults aged 65 and over that included 935,887 vaccinated people and 935,887 unvaccinated people.
The results are modest but exciting, especially considering how much time and effort is being invested in slowing and reversing the disease. According to FuturismAbout 5.1 percent of those with previous flu vaccinations developed Alzheimer’s, compared with 8.5 percent of unvaccinated patients who were later diagnosed with the disease.
“We found that influenza vaccination in older adults provides protection against Alzheimer’s for several years,” said Avram Bukhbinder, a UTHealth Houston graduate student and first author of the study.
“The strength of this protective effect increased with the number of years a person received an annual flu vaccine: in other words, the rate of developing Alzheimer’s disease was lowest among those who consistently received the flu vaccine every year,” he says.
Other vaccines may have similar effects
“Future research should evaluate whether influenza vaccination is also associated with the rate of symptom progression in patients who already have Alzheimer’s,” added Bukhbinder.
Most importantly, researchers do not know the underlying mechanisms that might explain the difference between vaccinated and unvaccinated individuals, or if such a difference exists.
“Because there is evidence that several vaccines can protect against Alzheimer’s disease, we think this is not a specific effect of the flu vaccine,” said Paul Schulz, a physician at UTHealth and lead author of the study.
“Instead, we believe that the immune system is complex, and some changes, such as pneumonia, can activate it in a way that worsens Alzheimer’s disease,” he continued.
The data must be researched in detail
But there may be other reasons.
“Other things that activate the immune system may do so in a different way, one that protects against Alzheimer’s disease,” he added.
In short, the data show an interesting piece of information that deserves further investigation.
“Clearly, we still have a lot to learn about how the immune system worsens or improves outcomes in this disease,” Schulz said.