Influenza Vaccination and Dementia

Regular Influenza vaccinations might also protect against dementia. A retrospective study of 120,000 American veterans suggests that vaccination reduced the risk of developing dementia by 12 percent[1].

On average, the veterans were 75.5 years of age. Of them 3.8% were female and 96.2% were male. The results were that veterans who had their regular influenza vaccination were significantly less likely to develop dementia compared to veterans without vaccination.

However, veterans with less than six yearly vaccination vs. none at all had similar risks for dementia. But veterans who had six or more Influenza vaccinations vs. none at all had a significant lower risk for dementia.

Thus, getting vaccinated against Influenza is associated with lower risk for dementia but only if you have received the vaccine for at least six years. This is consistent with the hypotheses that vaccinations may reduce risk of dementia by training the immune system and not by preventing specific infectious disease.

If vaccines are identified as causative factors in reducing incident dementia, the researcher think, they offer an inexpensive, low-risk intervention with effects greater than any existing preventive measure.

Which means that scientists have found another reason to get yourself vaccinated against Influenza (and by extension against Covid-19).

[1] Wiemken et al: Dementia risk following influenza vaccination in a large veteran cohort in Vaccine – 2021