Yeah, we knew that: dementia risk rises as activity rates fall

That's according to a new study published in the Journal of the American Medical Association (or JAMA).  Other studies we've looked at have told us the same thing, but this one has a very large cohort of subjects - 50,000 people in Great Britain.  

The British maintain a very extensive database of medical information on it's citizens called the UK BioBank.  For this study, researchers looked at data entered for the 50,000 subjects, 60 years of age or older, during the period 2006 to 2010.  Individuals were tracked for an average of seven years.

And the results? Seniors with 12 hours a day of inactivity over a 24 hour period experienced an increased risk for dementia of 63%.  Those who were idle around 15 hours a day had a 320% increase in dementia risk.

This was a longitudinal study, and so we connect cause and effect by inference.  Or perhaps by guessing.  For example, we don't know why people were idle -- perhaps it was a consequence of their existing dementia.  If we knew that, it might change our understanding of the meaning of the results.  This is a weakness in this type of study, although such a large group of subjects is still very informative.

As we've said before, "interventional" or "experimental" studies are more informative.  They actually change something and measure the results rather then simply following a population.  They also use control groups for comparison whose behaviors and other elements were not changed.

An important example of an interventional study is the FINGER study which we discussed previously, both in this blog and in Beating the Dementia Monster.  The study changed behaviors and measured results.  The study conclusions sent shock waves throughout the dementia study community.  

One of concepts behind the scientific method is that others should be able to reproduce your results.  And so there are currently studies all over the world trying to duplicate the FINGER results.  In the United States, we hope the US Pointer study will do this.  The US Pointer study finished recruiting in March of this year and is to last two years.  So it will be late 2025 at the earliest before we see results.  Nevertheless, we have high expectations.  

I expect the US Pointer study to confirm my real-life experience, that changing life style can actually reverse the progress of Alzheimer's disease.  We see this in mice, we think we saw it in the FINGER study, but we want a solid confirmation in a large, well controlled, diverse population.