Breakthrough study finds first intervention to reduce Alzheimer’s incidence
New results from a large, 20-year, NIH-funded study (the ACTIVE Study) show it’s possible to prevent a diagnosis of Alzheimer’s and related dementias. The researchers found that a modest amount of the right kind of brain training can substantially reduce the risk of such diagnoses. These results should usher in a new age, in which we recognize dementia as a preventable chronic condition that you can be proactive about.
Consider where we were before this finding: A soaring number of people are affected by dementia. Decades of spending hundreds of billions of dollars on pharmaceutical research have yielded only a few expensive new drugs that slightly slow the rate of Alzheimer’s decline. We have many observational studies (but few gold-standard randomized controlled trials, showing cause and effect) suggesting many lifestyle changes could have a good effect, leaving many of us confused about what to do.
This new study is a game changer.
The ACTIVE study enrolled more than 2,800 older adults (average age 74 at study onset) back at the turn of the Millennium. Researchers randomized them into four groups: a control group, a memory training group (which learned mnemonic and other strategies for improving memory), a reasoning training group (which learned problem-solving strategies), and a speed training group (which engaged with computerized, progressively-challenging, individually-adaptive, speed-of-processing exercises). Each participant in a training group was asked to participate in class sessions that were 60-75 minutes in length, twice per week, for the first five weeks of the study. A subset of each training was also asked to participate in four “booster” sessions in month 11 and month 35.
When I first learned of this study 20+ years ago, I thought of it as like a barroom bet among gerontologists and psychologists about what was most important for successful aging: memory, which is what most people worry about, reasoning which requires the executive function skills needed to live independently, or speed and attention, which brain science nerds like me view as underpinning all of higher cognitive function (including memory and reasoning).
Back then, I’d been working on issues of aging in my lab at UCSF for more than a decade, using auditory speed-of-processing exercises to improve the cognitive performance, brain health, and general health of aging rats in the development of neuroplasticity-based therapeutics. I don’t think you’d be surprised that, had I been in on this fictional barroom bet, I would have bet on the speed training.
Speed training is, in fact, the only one of the three training programs to achieve significantly better results than the control group. The speed training sub-group, asked to train for a total of less than 24 hours (10-23.5 hours) spread over the first three years of the study, showed 25% lower incidence of dementia diagnoses at the end of the 20-year observational period than the control group. The memory and reasoning groups and the speed training subgroup asked to train less (only in the first month) were not statistically better than the control group.
As a result, we now know from a long, gold-standard trial what you can do to lower the incidence of dementia — to a level of certainty never before attained.
Of course, research always sparks new questions. What if they had trained more? From the study, we know more is better. A subgroup that only trained in the first month did not have significant changes at 20 years.
Also, less than 24 hours of training spread over 36 months is a very light schedule. It would be nice to know the optimal schedule for each person — but now we do know a very modest amount has a 20-year protective effect, and that more is better.
And what if the training were extended to other modes, and to higher levels of neurological operation? Other studies indicate that broader training would more broadly and strongly improve organic brain health
As a result, we now know from a long, gold-standard trial what you can do to lower the incidence of dementia — to a level of certainty never before attained.
Of course, research always sparks new questions. What if they had trained more? From the study, we know more is better. A subgroup that only trained in the first month did not have significant changes at 20 years.
Also, less than 24 hours of training spread over 36 months is a very light schedule. It would be nice to know the optimal schedule for each person — but now we do know a very modest amount has a 20-year protective effect, and that more is better.
And what if the training were extended to other modes, and to higher levels of neurological operation? Other studies indicate that broader training would more broadly and strongly improve organic brain health
There are now simple online tools to more closely monitor cognitive gains and declines, so people should be able to set their own very personalized schedule with continuous monitoring on their phones, tablets, and computers. None of this was possible even five years ago.
I anticipate there will be a robust scientific debate about what mechanisms of action account for these exciting results. Some will speculate that doing the speed exercises in some way grows cognitive reserve. That works for me because, in my view, speed-of-processing equates with cognitive reserve.
To my mind, the INHANCE Study, published in October by researchers at McGill, manifests another important contributor to this training-driven protection. It found that a modest amount of speed training resulted in an upregulation of the production and expression of acetylcholine (the “pay attention” brain chemical). Production of acetylcholine has long been known to decline with age and plummet with pre-dementia and dementia. No other intervention has ever been shown to reverse its downregulation in production. Acetylcholine, of course, is also a critical enabler of brain plasticity, necessary to improve and sustain organic brain health.
We should remember that a fast brain necessarily represents information in higher fidelity and in more coordinated, reliable, and recordable electrical forms. Psychologists have extensively documented the high correlations between speed-of-processing and cognitive performance ability in almost every operational domain.
With this new research outcome, clinical practitioners can help monitor and manage the brain health of older adults in their care.
This research has just made a great and practical advance that will change what we do. And, while the research always continues, let’s pause to celebrate the advance that just happened.
