Flu Shot and Pneumonia Vaccine Might Reduce Alzheimer's Risk, Research Shows

Two studies presented Monday at the annual Alzheimer's Association International Conference offer evidence that flu and pneumonia vaccines may guard against Alzheimer's disease as well, reports National Public Radio . In one study, investigators from the University of Texas sifted through a national database of millions of medical records, seeking factors that affected the risk of getting certain diseases, including Alzheimer's. "One of the things that came back was flu shots," says Albert Amran with the University of Texas Health Science Center. People who received at least one flu shot had a 17 percent reduced risk, while those who were regularly vaccinated saw that risk drop another 13 percent. The second study considered the combined effect of flu and pneumonia vaccines. Researchers from Duke University and the University of North Carolina examined the medical records of more than 5,000 people who were at least 65 years old, and those receiving a pneumonia vaccine before age 75 were at least 25 percent less likely to be diagnosed with Alzheimer's. However, a flu vaccine in addition to the pneumonia vaccine did not further reduce risk. The studies suggest that the vaccines may be protective because diseases they are designed to prevent affect the brain, while another possibility is that they fortify the immune system.