It was the “two-thirds” in the press release headline that grabbed me: “Nine risk factors may contribute to two thirds of Alzheimer’s cases worldwide.”
So of course I read more about the new study:
Nine potentially modifiable risk factors may contribute to up to two thirds of Alzheimer’s disease cases worldwide, suggests an analysis of the available evidence, published online in the Journal of Neurology Neurosurgery & Psychiatry.
The analysis indicates the complexity of Alzheimer’s disease development and just how varied the risk factors for it are. But the researchers suggest that preventive strategies, targeting diet, drugs, body chemistry, mental health, pre-existing disease, and lifestyle may help to stave off dementia. This could be particularly important, given that, as yet, there is no cure, they say.
How I wish this meant that we can reduce our risk of Alzheimer’s by two-thirds. But no matter how I mangle the statistics, it doesn’t. Here’s what it does suggest, according to Dr. James Hendrix, director of global science initiatives for the Alzheimer’s Association: that for up to two-thirds of people who have Alzheimer’s, these modifiable risk factors may have contributed to it, and probably to when they got it.
“So,” he says, “if you were going to get Alzheimer’s, because maybe you had a genetic predisposition, and you take very good care of yourself, maybe you don’t get it until you’re 85 or 95. But if you smoke or you’re overweight or don’t exercise, maybe you get Alzheimer’s at 75. That’s really what this says — these could be contributing factors to if you get Alzheimer’s or when you get Alzheimer’s. It increases your risk.”
Of course, we’ve been hearing for years — at least since those smart Minnesota nuns got famous in 2001 — about how mental challenges like crossword puzzles could be linked to lower Alzheimer’s risk. But this latest paper seems part of a broad shift based on growing evidence about a far greater array of “modifiable risk factors.”
Exhibit No. 1: This summer, the Alzheimer’s Association ran a campaign on “10 Ways to Love Your Brain,” encouraging people to exercise, keep learning and quit smoking, among other advice. Exhibit No. 2: A round-up paper in the journal Alzheimer’s & Dementia laying out the levels of evidence on which lifestyle and health changes could protect people against Alzheimer’s.
The findings are relentlessly commonsensical: Many of the usual suspects that we already know are good for our health — exercise, heart-healthy diet, sleep, weight and blood pressure control — also appear to help fend off Alzheimer’s.
I asked Dr. Gad Marshall — a neurologist and associate medical director of clinical trials at the Center for Alzheimer Research and Treatment at Brigham and Women’s Hospital — how he’d respond to a neighbor who says, “Hey, I hear I can really move the needle on my risk of Alzheimer’s!” Continue reading