Alzheimer’s & Dementia has “temporarily withdrawn” a 2012 abstract, slated for publication next month, linking Alzheimer’s disease with exposure to dental x-rays.
The author is Caroline Rodgers, a self-described “independent writer/researcher who investigates public health issues and advocates for change.” Although we can’t find the text, we’re guessing that its premise is similar to that of her 2011 paper in Medical Hypotheses, titled “Dental X-ray exposure and Alzheimer’s disease: a hypothetical etiological association.”
Here’s the abstract from that paper:
Despite the fact that Alzheimer’s disease was identified more than 100 years ago, its cause remains elusive. Although the chance of developing Alzheimer’s disease increases with age, it is not a natural consequence of aging. This article proposes that dental X-rays can damage microglia telomeres – the structures at the end of chromosomes that determine how many times cells divide before they die – causing them to age prematurely. Degenerated microglia lose their neuroprotective properties, resulting in the formation of neurofibrillary tau tangles and consequently, the neuronal death that causes Alzheimer’s dementia. The hypothesis that Alzheimer’s is caused specifically by microglia telomere damage would explain the delay of one decade or longer between the presence of Alzheimer’s brain pathology and symptoms; telomere damage would not cause any change in microglial function, it would just reset the countdown clock so that senescence and apoptosis occurred earlier than they would have without the environmental insult. Once microglia telomere damage causes premature aging and death, the adjacent neurons are deprived of the physical support, maintenance and nourishment they require to survive. This sequence of events would explain why therapies and vaccines that eliminate amyloid plaques have been unsuccessful in stopping dementia. Regardless of whether clearing plaques is beneficial or harmful – which remains a subject of debate – it does not address the failing microglia population. If microglia telomere damage is causing Alzheimer’s disease, self-donated bone marrow or dental pulp stem cell transplants could give rise to new microglia populations that would maintain neuronal health while the original resident microglia population died.
Rodgers, who goes by the blog handle “Science Siren,” submitted public testimony in support of her theory at a meeting last month of the U.S. Department of Health and Human Services’ Advisory Council on Alzheimer’s Research. Her take-home message:
It is not realistic to believe that decades of dental X-ray exposure would be without consequence for all people. The question is not, “Why should we consider whether dental X-rays are causing Alzheimer’s,” but rather, “Why didn’t we think of this sooner?”
Rodgers told us that she presented the poster last July at a meeting in Paris of the Alzheimer’s Association.
The abstract was not included in the Journal’s special supplement of conference abstracts, which is why it is being published in the main journal in March.
And she said the withdrawal was not a retraction — the published abstract will be forthcoming. An official at Elsevier, which publishes Alzheimer’s & Dementia, informed her that the abstract
was withdrawn as an “article in press” because it was an abstract for a poster session, not a full article. He said, “We specifically did not use the word ‘retracted’ because we did not want to indicate there was anything wrong with it.” The abstract will be published in the March issue, as planned.
We confirmed that with Elsevier, and learned that the problem arose from a misclassification of the abstract in the editorial office of the journal.
Rodgers hasn’t limited her research to the causes of Alzheimer’s disease. Another area of interest for her is an alleged link between autism and exposure to prenatal ultrasound:
If prenatal ultrasound is the primary reason siblings of children with autism are at higher risk for being diagnosed with ASD, it would explain why previous sibling studies did not show as high a sibling risk: as ultrasound’s potential acoustic output, applications and occasions have increased, so has the risk.
And we might expect even more theories from her. After all, as she notes on her blog:
I have developed original ideas regarding the part that heat plays in everything from the onset of labor to the location of body hair to the roller coaster of circadian rhythms we experience every day.
Most exciting is how these conjectures, if proven true, can have a beneficial impact on public health.