WANGERSKY: ALZHEIMER’S LINKED TO GINGIVITIS
Lots of science is reported in the media – often somewhat breathlessly – long before all of the dots have been fully connected. News stories claim that a vaccine or cure might be imminent, mere years away, for some crucial bane of human existence, but the years tick by and the expected vaccine never quite gets there.
Keep that in mind, then, while thinking about a story in the journal New Scientist this week that suggests a cause may have been found for Alzheimer’s disease, and that the cause could be Porphyromonas gingivalis – the main bacteria in gingivitis, or gum disease.
I worry about gum disease a lot – primarily before bed, when I’m brushing my teeth, rinsing with germ-fighting mouthwash or flossing. I’ve often wondered why there hasn’t been a sustained effort to fight it, beyond whatever the latest mouthwash promises.
Turns out I haven’t been reading enough – but the work that’s being done isn’t just for the sake of your gums.
The mechanism may interest me a heck of a lot more than it interests anyone else, so I’ll just give you a thumbnail: studies of brain tissue in Alzheimer’s has been found to have amyloid plaques – accumulated proteins. Those proteins are now believed to be a defence mechanism against infection – and Alzheimer’s patients have been found to have infections of P. gingivalis in their brain tissue. More to the point, in brain samples from Alzheimer’s patients checked in a recent study, 96 per cent showed the presence of toxic enzymes that the P. gingivalis was using to feed on brain tissue. And those same enzymes, called gingipains, have been shown in another study to damage and kill neurons, causing dementia.
Not a complete smoking gun, but a fascinating start, especially because at least one study has found a way to block the dementia-causing gingipains.
So, a long way off, but an interesting take.
In a way, it reminds me of a different issue – the suggestion, one long derided in the medical community before it was proven to be true – that the majority of stomach ulcers aren’t caused by stress or bad eating, but by a bacteria called Helicobacter pylori. The bacteria can now be treated by a two-week course of antibiotics. But back to P. gingivalis. There are interesting side issues, too. Treatment for Alzheimer’s is a medical issue, and is covered, albeit not completely, through our national medicare program.
Oral care, however, is not. Chances are, when it comes to dental care, if you’re not insured, it’s a cost that is both necessary and difficult to finance. Chances are, when times are tight, dental care has been one thing to go by the wayside.
That makes a possible precursor for Alzheimer’s a class issue, in a way. If you can afford dental care, or if your job has a dental plan, you probably have a better chance at getting regular dental treatment – and have had a better shot at having gingivitis recognized and treated to the extent that it now can be.
Still, an Australian team is working on a vaccine for P. gingivalis that is now in clinical trials.
How astounding would it be if it turned out that it was a doubleedged sword – getting rid of a dental scourge, while also finding a meaningful vaccine for Alzheimer’s disease. Dementia is the fifth-largest cause of death worldwide, and some 70 per cent of those dementia cases are Alzheimer’s.
The health savings would be truly amazing if a vaccine works – and perhaps it would be enough of a savings to bring basic dental care in under the umbrella of medicare.
Where, legitimately, it should have been all along.