May 14, 2013

Dementia: sugar or iPads?

I’ve got no objection to speculative or controversial research being in the media, as long as it’s marked as such, which it often isn’t.

In September, the Herald told us researchers were finding that dementia was due to high blood sugar, essentially a diet and exercise problem.

Today we learn that it’s actually ‘technology’ that causes dementia, in a, like, totally interconnected way

“Considering the changes over the last 30 years – the explosion in electronic devices, rises in background non-ionising radiation – PCs, microwaves, TVs, mobile phones; road and air transport up four-fold increasing background petro-chemical pollution; chemical additives to food, et cetera,” Professor Pritchard said.

“There is no one factor rather the likely interaction between all these environmental triggers, reflecting changes in other conditions.”

What actual research paper found is that the ratio of  diagnoses of neurological diseases  to deaths had risen, across 16 countries, indicating that people live longer after diagnosis.  This could be due to earlier onset, the explanation Prof. Pritchard gives, but they actually don’t do any correction for changes in diagnosis.  Earlier diagnosis could just mean earlier diagnosis, not earlier onset of disease.  Changes in how deaths are classified could also have played a part, although these are less likely to be consistent across countries.

The research paper makes a lot of the fact that dementia in women increased later than in men, attributing this to women entering the workforce and getting exposed to more scary modern stuff (without any actual data on the relative exposure to modern stuff in the workplace and at home).  Surely another possible explanation is that in the modern world, loss of memory and cognitive function is taken seriously in elderly women, but that 30 years ago it just wasn’t regarded as a medical problem.


Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »