High-dose flu vaccine may cut risk by 55%

• Researchers have been already-used vaccines to doubtlessly assist decrease threat for Alzheimer’s illness and different kinds of dementia.
• One such vaccine is the influenza vaccine, which earlier research present could assist decrease an individual’s dementia threat.
• A brand new research discovered that older adults who obtain a high-dose influenza vaccine could decrease their Alzheimer’s illness threat greater than these receiving a normal vaccine dose.

As researchers proceed to search out new methods of serving to to cut back an individual’s threat for Alzheimer’s disease and different kinds of dementia, some are inspecting vaccines which can be already getting used to decrease threat for different ailments.

For instance, a research printed in December 2025 discovered that the shingles vaccine may assist decrease an individual’s threat for dementia, in addition to gradual illness development.

Now a brand new research printed within the journal Neurology reviews that older adults who obtain a high-dose influenza vaccine could decrease their Alzheimer’s illness threat greater than these receiving a normal vaccine dose.

Paul Schulz, MD, professor and neurologist at UTHealth Houston, and lead creator of this research, defined to Medical Information At present that this new research continues earlier analysis, together with a research he and his colleagues published in 2022.

The 2022 research discovered that the influenza vaccination could assist scale back the chance of Alzheimer’s illness by as much as 40%, with six annual vaccinations.

“The nagging query after these research was whether or not we had a real discovering versus a spurious one resulting from ‘the wholesome survivor impact,’ additionally referred to as ‘the wholesome vaccinee impact’,” Schulz advised MNT.

“That signifies that of us who get vaccinated could usually have a more healthy way of life: Similar to they get vaccinated, additionally they train, take their blood pressure and cholesterol medications, see their docs usually, eat more healthy, and many others.”

– Paul Schulz, MD

“Serendipitously, I gave a chat on the Houston Public Well being Division, and so they requested whether or not there was a dose-dependent impact,” he continued. “I wasn’t conscious that folk over age 65 get a vaccine that’s four times the strength of the usual vaccine resulting from our immune methods being much less responsive as we become older.“

“However, it seems that not everybody over age 65 will get the excessive dose influenza vaccine. The well being division and pharmacies can run out of the excessive dose, and many others,” stated Schulz.

“That led to the paper [where] the objective was to check whether or not, after we enrolled solely individuals who had been vaccinated [whether with a high or low dose], there was nonetheless a protecting impact of vaccination on lowering Alzheimer’s illness threat,” he added.

After analyzing well being information from about 200,000 members ages 65 and older, researchers discovered that those that obtained the high-dose influenza vaccine lowered their Alzheimer’s illness threat by about 55%, in comparison with 40% with those that obtained the usual vaccine dose.

Moreover, scientists reported discovering the protecting impact of the high-dose flu vaccine was stronger in ladies than males.

“We don’t know why that’s, however we do know that ladies and men’s immune methods are very completely different,” Schulz stated.

“Males are inclined to have a stronger innate immune response (recognizing pathogens as overseas the primary time we see them) and girls are inclined to have a stronger antibody-mediated response. The antibody response is how vaccines work, after all, by having us make antibodies which can be prepared to connect to pathogens to which we’re uncovered,” he continued.

“So, our speculation is that ladies could have a extra vigorous immune response. And, immune exercise is concerned in how mind cells are misplaced in Alzheimer’s illness. So, a extra vigorous immune response to vaccines may translate right into a larger impact of vaccines in ladies.”

– Paul Schulz, MD

Questions stay as to how a vaccine for the flu may assist decrease an individual’s threat for Alzheimer’s illness.

Dung Trinh, MD, an internist for MemorialCare Medical Group and chief medical officer of the Wholesome Mind Clinic in Irvine, CA, advised MNT there are a couple of biologically believable potentialities.

“First, high-dose influenza vaccines generate a stronger immune response than standard-dose vaccines in older adults, and which will scale back the probability or severity of influenza an infection and the systemic irritation that comes with it,” Trinh, who was not concerned within the latest research, defined.

“Since continual irritation and neuroinflammation are thought to play a task in Alzheimer’s illness, lowering inflammatory stress over time may very well be one pathway,” he hypothesized.

“Second, there’s rising curiosity in the concept some vaccines could ‘practice’ or modulate the immune system in ways in which affect mind well being extra broadly, though that is still theoretical,” he continued.

“The vital level is that this research doesn’t show the mechanism; it raises a reputable speculation that stronger safety in opposition to an infection, stronger immune stimulation, or each may contribute to decrease threat of Alzheimer’s.” Trinh stated.

MNT had the chance to talk with Rehan Aziz, MD, DFAPA, vice chair of schooling, psychiatry at Hackensack Meridian Jersey Shore College Medical Heart, and affiliate professor of psychiatry and neurology at Hackensack Meridian Faculty of Medication in New Jersey, who commented he was excited concerning the research’s findings.

“We have already got compelling information suggesting that the shingles vaccine could scale back the chance of Alzheimer’s dementia, and this new research signifies that the flu vaccine may supply an analogous protecting profit,” Aziz, who was likewise not concerned on this research, defined.

“In my apply, I already suggest the shingles vaccine to older adults not just for its main goal but in addition for this potential cognitive profit. Now, we will prolong that very same reasoning to the annual flu shot,” he advised us.

“Moreover, this research gives a robust scientific rationale for recommending the high-dose flu vaccine particularly, because it demonstrated a larger discount in Alzheimer’s threat in comparison with the standard-dose model,” he added.

MNT additionally spoke with Peter Gliebus, MD, chief of neurology and director of cognitive and behavioral neurology at Marcus Neuroscience Institute, part of Baptist Well being South Florida, who stated he discovered this analysis promising.

“Nevertheless, the research’s limitations, resembling a brief follow-up interval and reliance on claims information, imply the findings ought to be interpreted with warning,” Gliebus, who was additionally not concerned within the research, stated. “Extra analysis is required to verify these outcomes and perceive the mechanisms concerned.”

“Future analysis ought to embrace longer follow-up research, randomized managed trials, and investigations into the organic mechanisms behind the protecting results of high-dose influenza vaccines,” he detailed. “Research also needs to deal with numerous populations, incorporate biomarker information, and discover the vaccine’s influence on cognitive decline development.”