Flu Shots and Alzheimer’s Disease

One of the benefits of large cross-sectional studies, especially in the age of electronic medical records, is that medical tests and treatments can be examined while examining diagnoses at the same time. The Veterans Health Administration is one of many medical databases that can identify relationships between health factors and the onset of disease.

In a recent study, researchers used a large medical records database called Optum Clinformatics Data Mart. The methodology section was long, but essentially they divided potential subjects into those who did not get a flu vaccination at all and those who got at least one flu vaccination every year or more. They identified their potential subject list and then tracked them for four years to see if they received a diagnosis of Alzheimer’s disease (AD). In case you were wondering, people under 65 were excluded because AD does not manifest itself appreciably until after that age.

The results were more than a little interesting. Those who got at least one flu shot had a 40% reduced risk of getting diagnosed with AD. Before you even think, as I would have, “How many subjects were there?”–there were close to a million subjects in each group. The better question is how would a vaccination reduce the risk of getting AD? We’ll examine that question on Saturday.

What are you prepared to do today?