On Preventing Dementia

The Wellness Diaries - Part 3

Dementia is on my mind, as well as the advice I give to patients who are afraid of it and want to know how to prevent it.

I just finished reading Joshua Henkin’s sensitive and poignant new novel, Morningside Heights. It begins in 1970’s New York, and tells the story of a young girl, Pru, who moves to the City to become an actress and falls in love with a prominent English professor at Columbia University. Some years later the professor develops early-onset Alzheimer's disease, and the book beautifully chronicles his inexorable decline and the devastating impact it has on Pru and their family.

At the same time, I’ve noticed an increasing number of patients who come to me with complaints of memory loss and apprehension in their eyes. “Is it something to worry about?” they ask, “I have trouble remembering names, where I parked the car, or what I was about to say. Could it be Alzheimer’s?”

The causes of dementia can be roughly divided into three groups: Alzheimer’s, which makes up more than half of cases; Vascular, such as resulting from stroke, high blood pressure, or diabetes; and Other, a potpourri ranging from Lewy body disease to the prion-mediated Creutzfeldt-Jakob, or “Mad Cow,” disease. 

There are also dementia mimics: cognitive impairment secondary to disorders such as anxiety and depression; electrolyte abnormalities; infections; vitamin deficiencies; substance abuse; medication side effects; or other diseases altogether, like post-Covid brain fog.

If dementia is your concern, then I have good news and bad news.

The good news is that if you think you have dementia, you probably don’t.  Studies show that self-reported memory loss is uncorrelated to the development of future dementia - i.e. you are no more likely to develop dementia than those who think their memory is fine. 

On the flip side, informant-reported memory problems are correlated to the development of future dementia - i.e. if someone close to you is worried about it even though you are not, it might be worth a work-up.

The bad news is that if it is dementia there is not much to be done about it. 

Notwithstanding recent reports to the contrary, dementia is still a mostly untreatable - and definitely incurable - disease. You may have read reports of a new Alzheimer’s drug, Aduhelm, and the drama surrounding its recent FDA approval. I’m not going to take a stand on that other than to note that while the studies show it decreases the formation of plaques in the brain, it does nothing to help the cognitive decline (the operation was a success but the patient died!).

When I see a patient with memory complaints, I’ll take the history, do an exam including a mental status evaluation, and send out labs to rule out underlying disease. I may order brain imaging or refer to Neurology, but if everything else is normal then that generally ends up being unrevealing. The gold standard in questionable cases is neuropsychiatric testing which can be onerous and expensive.

And then there’s prevention.

As with any incurable disease, prevention is obviously the way to go when it comes to dementia, and the evidence seems to suggest that more than a third of cases can be prevented by modifying a set of risk factors. These include smoking, hypertension, diabetes, obesity, and physical inactivity. I always counsel about these anyway so if fear of dementia means added motivation then I’m all for it.

Other preventable risks include midlife hearing loss, late- life depression, and social isolation. A good primary care doctor should be on the lookout for these regardless.

But my favorite preventive factor of them all? Cognitive reserve. 

Think of cognitive reserve as your brain’s ability to improvise and find new ways to get things done. The concept originated in the late 1980’s when researchers described individuals with advanced brain changes due to Alzheimer’s on autopsy, but no signs of dementia while they were alive. 

It’s like the exact opposite of Aduhelm: all of the plaques but none of the cognitive decline.

Cognitive reserve is to the brain what fitness is to the body, and the path to both is exercise. In both cases, the goal is a strong, flexible and agile body or mind that will be able to withstand greater amounts of damage before it reaches the tipping point of functional disability.

As with physical exercise, brain exercise should be difficult, and push you into unfamiliar territory. Just as a walk is great but not as good as a run, reading a novel is great but not as good as doing math or learning a new language or an instrument, especially if these activities are unfamiliar.

Still, just because brain exercise should be hard enough to “make you sweat,” doesn’t mean it’s not allowed to be fun. Examples include doing crossword puzzles; reading an article or taking a class on an unfamiliar topic; or even learning to paint or draw.

The key is to stretch your brain into cognitive domains that you don’t normally use.

At a recent college tour of UVA, we learned that students don’t refer to themselves as Freshmen, Sophomores, Juniors and Seniors but rather as First Years, Second years, etc. Apparently this dates back to Thomas Jefferson, the school’s founder, who wanted to make the point that learning should be a lifelong endeavor, not one that culminates after four years.

In a similar vein, a third-year medical resident is typically referred to as a PGY3 (post-graduate year three) until graduation, at which point they become an “attending.” I will never forget the seasoned ER attending at Beth Israel who referred to himself not as an “attending,” but as a PGY20, in the spirit of Jefferson.

For those of you who are curious how I practice what I preach, I try to start off every day by learning a page of Talmud, a dense Jewish text, written in Aramaic, that ranges across every imaginable subject and cognitive domain, and can get famously difficult. Amusingly, I once read that learning Talmud has become popular in South Korea, of all places, as an educational fad having nothing to do with religion.

My personal experience has been that however protective it may be against dementia, the daily discipline and habit of learning is also protective against the vicissitudes of life - as a wellspring of creativity; a foundation for intellectual independence; a bulwark against burnout; a source of fresh perspective. It adds interest, color and texture to the world, as well as joy, contentment, and metaphysical consolation.

Furthermore, could there be a way in which the intrinsic value of learning can be seen as a counterbalance to the tragedy of dementia? As Chaucer wrote, all good things must come to an end - to the extent that nothing can be worse than losing one’s mind, nothing can be better than having made good use of it.