VACCINATION AGAINST PNEUMONIA IN THE ELDERLY MAY REDUCE ALZHEIMER’S RISK

Abstract

Accumulating evidence suggests that infections may contribute to Alzheimer's disease (AD) development. Various pathogens were considered in this regard, indicating a possibility that compromised host ability to respond to infection may play major role in this connection. Few studies, however, tested interventions that may improve the immune response to infection and overall robustness/ resilience of the immune system, and through this protect against AD. One such candidate intervention could be pneumonia vaccine that has been shown to have a broad effect on morbidity and mortality in the elderly in several studies. We investigated the impact of the vaccination against pneumonia (with and without an accompanying flu shot) between ages 65 and 75, on the risk of AD occurrence after age 75, in elderly (65+) participants of the Cardiovascular Health Study (CHS), using both logistic and Cox models. We found that individuals, who were vaccinated against both pneumonia and flu before the age 75, had significantly decreased chances of AD occurrence between ages 75 and 85 in logistic model (p-value=5E-06; OR=0.43). People who had pneumonia vaccination without flu shot before the age 75 also had significantly decreased risk of AD after the age 75, though less prominently (p-value=0.01; OR=0.67). Analysis, using Cox model supported these findings. Vaccination against pneumonia (alone or together with flu shot) could be a promising new candidate for repurposing in AD prevention, potentially acting through improving resilience of the immune system in the elderly. Further testing and validation of these effects in other human data is warranted. The study was supported by NIH grants R56AG059428 and R01AG046860.