text_1: Researcher: Alzheimer's vaccine could cut dementia in half, human trials may be next
text_2: This story reports on a study done in laboratory mice that showed a vaccine decreased the build-up of two proteins, amyloid and tau, that are associated with Alzheimer’s. The story mentions this was a mouse study and acknowledges it isn’t the only potential avenue under study to arrest those harmful substances. However, it gives an overly optimistic spin, using the word “promising” and playing up a speculative comment in a UT Southwestern Medical Center news release that dementia cases “could drop by half” if there’s a vaccine that delays the onset of Alzheimer’s by five years. The story also doesn’t caution that success in animals often doesn’t translate to benefits in humans, and that other treatments targeting these proteins have not panned out. Also missing: discussions of costs and potential harms and comments from independent sources. As the U.S. population ages, dementia is becoming more common. Millions of families are coping with a person who has a diagnosis of Alzheimer’s. Available treatments do not prevent or cure Alzheimer’s and at best slow down the progression of symptoms for short periods. Considerable effort has focused on new treatments that seek to break down or prevent the deposition of abnormal proteins that appear to increase as memory loss progresses. So far these new treatments have not been shown to help. Initially they were tried in individuals with advanced disease but now are being used in patients with mild symptoms as a way to prevent progression. Even here, trials have not shown positive results that are clinically meaningful. A vaccine to “prevent” Alzheimer’s is appealing in that it works even earlier in the process, maybe even before symptoms appear. However, it isn’t clear that a vaccine will actually improve clinical outcomes. The fact that this small study in mice led to several optimistic headlines — not just USA Today’s — reflects how desperate we are for progress. Regardless, news stories should not make a remedy sound closer and more certain than it is.