You may have heard the interesting reports about infections and Alzheimer’s disease mentioned at the July 2020 Alzheimer’s Association International Conference (AAIC). It appears that illnesses, such as the flu and pneumonia, may trigger inflammation in the brain that predispose the body to developing Alzheimer’s. The logical next question is: does preventing the flu and pneumonia lower a person’s risk for also developing Alzheimer’s disease? Some initial data presented at the AAIC conference addressed this question.

According to datasets from large populations (including The University of Texas Health Science Center at Houston), people who received even one flu shot in prior years were less likely to develop Alzheimer’s. People who received flu shots every year had an even further reduction in risk of developing Alzheimer’s. In another study from Duke University, individuals who received pneumonia vaccines in combination with the flu vaccines were less likely to develop Alzheimer’s. The more vaccines that were received over time resulted in even lower risk in developing the disease in this specific study as well.

It is important to note that these studies are correlational, meaning it is unclear if the vaccines themselves provide protection or if the individuals who are vaccinated also engage in other healthy behaviors that make them less likely to develop Alzheimer’s. To be clear, it has not yet been proven that vaccines can lower risk of Alzheimer’s. This early data simply suggests it is a possibility that should be investigated. Maria Carrillo of the Alzheimer’s Association recently stated, “This research, while early, calls for further studies in large, diverse clinical trials to inform whether vaccinations as a public health strategy decrease our risk for developing dementia as we age.”

Infection remains a leading cause of death in people with Alzheimer’s with patients being twice as likely to die from serious infections as those without Alzheimer’s. So even if vaccines don’t reduce one’s risk for developing Alzheimer’s, they may be proven to help extend Alzheimer’s patients lives. It is yet to be determined why people with Alzheimer’s are more likely to die from flu or pneumonia than their cognitively healthy peers.

In the midst of the COVID-19 pandemic, influenza and pneumonia vaccinations are of even more importance than usual. The health of the public would benefit tremendously if we discover vaccines also protect against Alzheimer’s. At the very least, these vaccines could potentially reduce disease severity and help save more lives of both healthy and vulnerable patients.

Article provided by Michele A. Kettles, MD, MSPH, Chief Medical Officer and preventive medicine physician at Cooper Clinic.

For more information on Alzheimer’s prevention, check out Dr. Cooper’s Recommendations for Alzheimer’s Disease Prevention.