Retirement Age and Dementia

Recent news reports have been touting the benefits of delayed retirement and the claim that this action will reduce the incidence of dementia. The Huffington Post started their article saying “People who delay retirement have less risk of developing Alzheimer’s disease or other types of dementia, a study of nearly half a million people in France found.” These statements were attributed to INSERM, the French government’s health-research agency based on a paper presented on Monday July 15, 2013 at the Alzheimer’s Association International Conference in Boston.

I have yet to see the paper and the INSERM website is in French. I am not fluent in that language. It would be useful to see the paper as the published results raise one very important question. The study as reported in the media says they included 429,000 workers and that nearly 3 percent had developed dementia. But the reports also state that the prevelance of Alzheimer’s, the most common form of dementia is about eleven percent.

The eleven percent figure is consistent with other studies. See here, here, and here. The rates vary greatly by age and sex.

My problem is that they study showed only three percent with dementia while the rate should be something over eleven percent. I have to ask what happened to the other eight percent and do I really want to rely on a study that claims to show the value of a delayed retirement when the rate with in the study is only three percent while the rate overall is eleven percent. That discrepancy cries out for an explanation. It is not given it the media reports. Perhaps there is a reason given in the paper itself.