Understanding Alzheimer’s and Tips to Protect Brain Health with Dr. Silky Pahlajani

A neurologist explains the science behind Alzheimer’s disease and shares simple things anyone can do to help keep their brain healthy.

In recognition of Alzheimer’s Awareness Month, Dr. Silky Pahlajani, a behavioral neurologist and neuropsychiatrist at NewYork-Presbyterian and Weill Cornell Medicine, describes how Alzheimer’s disease is diagnosed, the signs and symptoms of the disease, and the reasons why Alzheimer’s is more significant in women than in men. She also discusses ways to strengthen our brain health at any age.

Episode Transcript

Faith: Welcome to Health Matters, your weekly dose of the latest in health and wellness from New York Presbyterian. I’m Faith Salie.

November is Alzheimer’s Awareness Month, and today we’re talking to Dr. Silky Pahlajani, a behavioral neurologist and neuropsychiatrist at NewYork-Presbyterian and Weill Cornell Medicine who specializes in Alzheimer’s disease. Dr. Pahlajani, explains the difference between Alzheimer’s and dementia, how Alzheimer’s impacts women more than men, and what we can all do to protect our brain health. 

Faith: Dr. Silky Pahlajani, thank you so much for joining us.

Dr. Pahlajani: Thank you for inviting me.

Faith: To get started, what is the difference between dementia and Alzheimer’s?

Dr. Pahlajani: Yes, it’s a very common question, understandably so, because the terms dementia and Alzheimer’s are often used interchangeably. Clinically, dementia is a general term for a constellation of symptoms associated with memory loss severe enough to interfere with daily functioning. Alzheimer’s is just a type of dementia, the most common type associated with aging.

Faith: So we hear about Alzheimer’s, but we might not understand exactly what’s happening in the body. Can you describe Alzheimer’s from a medical point of view?

Dr. Pahlajani: Yes. Alzheimer’s clinically does consist of the predominant symptom of short term memory loss. For example, forgetting recent conversations or recently learned information, repeating questions. Other symptoms include misplacing things or putting them in odd places. Difficulty managing bills. Consistently losing track of the date. Confusion in familiar environments and navigating new ones. Decline in judgment and problem solving. As well as behavioral symptoms such as mood and personality changes. Perhaps an increase in irritability or anxiety. However, the key thing to remember is that these symptoms have to be severe enough to disrupt daily functioning for the diagnosis of Alzheimer’s dementia. And to your question about how we can tell pathologically, so basically on autopsy is the only way to definitively tell whether or not someone has Alzheimer’s. Um, and there are what we refer to as plaques and tangles in the brain which physically manifest and aggregate in the brain of a patient with Alzheimer’s. I would say 80 percent of the diagnosis is made by the clinical presentation that we are told really by family members of loved ones. And sometimes in the early stages, patients do start to recognize certain things, um, in themselves in terms of their memory decline, and then we use things like brain imaging and spinal fluid biomarkers which further validate our suspicion that a patient has Alzheimer’s type of dementia.

Faith: What role does genetics play in Alzheimer’s?

Dr. Pahlajani: Yeah, I think that’s a really great question because people often wonder about the chances of developing Alzheimer’s if there’s a positive family history. So there are two types of Alzheimer’s disease, early onset and late onset. Early onset, which does have a strong genetic component due to a gene called APOE4, and the symptoms occur prior to age 65, usually in their 40s or 50s. However, this occurs in those with two copies of APOE4, and that’s only 2 to 3 percent of the population, so it’s not the vast majority.

Most people with Alzheimer’s have the late onset form in which symptoms become apparent in their mid 60s or later. And about 15 to 25 percent of the population carries one copy of APOE4, which is a risk factor for developing AD. However, there are people with APOE4 who never go on to develop the disease, and others without APOE4 who do. So it’s not solely dependent on having APOE4.

Faith: I would assume most people aren’t tested for this genetically. Is that right?

Dr. Pahlajani: Absolutely correct. Testing for this is really kind of, uh, under study right now because like I said, you can have it and not get it or you can not have it and still get it. However, if there’s an early family history where, you know, there were someone in the family, started developing memory decline, like in their forties or fifties, that’s when we really advise testing for the APOE4 gene because it can be passed on. And if there are two copies, then early onset is something, you know, that plays into a role of people deciding how they want to go about navigating that.

Faith: I have only recently learned something like two thirds of American Alzheimer’s patients are women?

Dr. Pahlajani: Yes. Women do have an increased risk of developing Alzheimer’s compared to men. And you’re right. In fact, of the 6. 2 million Americans with Alzheimer’s, about two out of three are women and, you know, unfortunately, the exact reason for this is not yet known. One explanation is that, on average, women do live longer than men. And the biggest, like I said, the biggest risk factor for Alzheimer’s is age. However, that alone really doesn’t explain why women are significantly at a greater risk for developing Alzheimer’s.

It’s hormonal differences that play a key role, specifically loss of estrogen during menopause. So it is possible that estrogen-only hormone therapy during early stages of menopause might be protective against developing Alzheimer’s. However, HRT, you know, is not for everyone because it has its own risks and the current evidence… It’s still just not yet enough to suggest that hormones should be prescribed as a prevention for Alzheimer’s. It’s not just the ovaries or the reproductive system that estrogen has an impact on, you know, we’re a whole body. We’re human, right, so connected from head to toe and similarly hormone changes also there’s a crosstalk between the brain and the reproductive endocrine system.

Faith: It’s so interesting to think about because you think, okay, well, then a person who was born a man has, has lived a life without the same levels of estrogen and they’re having lower cases of Alzheimer’s. It’s very perplexing.

Dr. Pahlajani: It is very perplexing and it’s an area of research that, you know, I think was not explored so actively, you know, prior to like maybe 15 years ago. And the more that we discover about this, the more likely we are to perhaps even find, um, a treatment, maybe in the future catered particularly for women’s brains.

Faith: I love the words “a future catered to women’s brains.”

Dr. Pahlajani: Isn’t it great?

Faith: I want to be here for that future and I want it tomorrow.

Dr. Pahlajani: I want it yesterday, but yes.

Faith: Yeah. Um, so is there anything else on on women and Alzheimer’s that that you want people to know?

Dr. Pahlajani: I think one thing that women should keep in mind is that stress actually impacts estrogen levels. So,

Faith: Hmm.

Dr. Pahlajani: you know, there’s a primary stress hormone called cortisol. When cortisol increases, estrogen levels actually go down. And when cortisol decreases, so when we’re less stressed and managing stress better, cortisol decreases, estrogen levels go back up. So that’s why it’s so important to reduce and manage stress levels, because it’s related to estrogen levels.

Faith: Are there estrogen supplements or perhaps estrogen rich foods that you sometimes encourage patients to take?

Dr. Pahlajani: Interestingly enough, not only is the Mediterranean diet good for brain health, but it’s also rich in plant nutrients. And a lot of plant nutrients are very estrogen rich or have kind of an estrogen like activity. And so we do recommend plant based nutrition, not just for women’s brains, but for brain health overall.

Faith: What are the risk factors for Alzheimer’s? We’ve talked about a genetic component. What are other risk factors?

Dr. Pahlajani: We know that vascular health such as blood pressure, cholesterol, diabetes. All of these things have a great impact when they’re unchecked or uncontrolled. Those are very, very big risk factors and can exacerbate cognitive decline and the onset of Alzheimer’s. So it’s not just plaques and tangles. It’s also, like I said, we’re a whole body and as a human, these other cardiovascular risk factors play a key role as well.

Faith: I’ve also seen headlines that connect sleep or, or lack of sleep with Alzheimer’s? What do we know about that?

Dr. Pahlajani: The way I describe it is that sleep is the garbage truck for your brain. It’s when the body gets rid of toxins and replenishes itself, and it’s also a time when memory is consolidated. So it’s no wonder that, when we don’t get proper sleep on a particular night, or if I’m on call and I’m not getting sleep that night, the next day, my memory is shot. That goes for anybody and everybody. I’m sure you’ve also noticed it in yourself on a night when we don’t, when you don’t get good quality sleep, our memory is all over the place. We can’t find our words. Uh, we can’t pay attention and focus. Our brain is foggy, so to speak.

Faith: So that’s a list of sad trombone risk factors. And yet, a lot of those are lifestyle factors right? That’s the good news?

Dr. Pahlajani: That is the good news. And luckily there are several categories of things we can do mitigating those risk factors. Not surprisingly, a big one is physical activity. You know, exercise is usually associated with physical health. What most people don’t realize is that exercise is also great for the brain, which is a fact backed by scientific data.

Faith: I love that.

Dr. Pahlajani: Right? That means there’s some level of control that we do have on this situation and what we’re specifically referring to is cardiovascular or aerobic exercise: so anything that raises your heart rate for at least 30 minutes, 4 to 5 times a week. Not only does exercise increase blood flow and oxygen to the brain, but it also releases various brain protective chemicals. Um, and of course, like I said, we can’t mention exercise without briefly talking about diet. So studies have shown that the Mediterranean diet is great for brain health. Omega 3s from fish are excellent. Or even from extra virgin olive oil. Um, flaxseed oil provides an adequate amount of Omega 3s, as well as antioxidant rich foods. We all know about berries. What a lot of people don’t know is that moderate amounts of coffee, about one to two cups a day, is also full of antioxidants.

Faith: We love that news around here.

Dr. Pahlajani: Coffee gets a bad rep every couple of years. Coffee is good for you, but again, in, in moderation, like anything else.

Faith: What about, uh, behavioral choices? Things, things we can choose about the way we lead our lives that can help us keep healthy brains.

Dr. Pahlajani: It’s very important to challenge our brain. With age, our brain tends to go on autopilot as we settle into our careers and have the same daily routine. But if the brain were a muscle, it’s important to cross train it. And the best way to do that is by learning something new, whether it’s a new language, an instrument, a card game, or really doing anything that’s out of your comfort zone. So, you know, the goal is not to be the best piano player or Spanish speaker, but to be in constant learning mode. If we do the same thing over and over, like a lot of people tell me they do crossword puzzles, which are great, I think people should do crossword puzzles. However, if you’ve been doing them your whole life and you’re very good at it and your brain is used to it, it’s really not a challenge at that point,

Faith: What role does social connection play?

Dr. Pahlajani: Yeah. You took the words actually out of my mouth. You know, during the pandemic, one of the biggest things that happened was social isolation, and we saw a significant decline in cognition for patients, let’s say, who had early stages of memory loss because if I were to say the most important thing, if you were to take away from any of these points, you know, of course, exercise and all the other things are very important, but social stimulation. Non screen time type of things, engaging with people. There is nothing that can really match the neuroplasticity and new connections our brain makes when we are actually interacting with other humans.

Faith: You’ve listed a whole bunch of, of good, healthy brain things we can do. When should people take these measures?

Dr. Pahlajani: Now, today, as soon as possible. I don’t think it’s ever too late to start doing some of these things. So one big factor is actually reducing, especially in our day and age, is reducing stress and anxiety levels. You know, everyone is stressed out. Everyone is anxious over something. And I have patients who actually tell me all the time that they’re worried about getting Alzheimer’s, they’re anxious about getting Alzheimer’s and what I tell them is worrying about memory loss can lead to memory loss because when our brain is occupied by anxiety and stress it, of course, will affect our ability to focus and hence retain information. You know, our brain is the powerhouse. Everything comes from the brain. So it’s important to really reduce stress for those who have, let’s say depression or low mood, how important it is to actually get adequate treatment for it or just at least address it because that is still stress and strain on the brain and that does impact memory and cognition.

Faith: So if there were a couple of takeaways you want people to have, what would they be?

Dr. Pahlajani: The takeaways should really be that what’s good for the heart is good for the brain, and that a healthy lifestyle is an investment into your cognitive future.

Faith: Dr. Pahlajani. Thank you so much for shedding light on all of this. It’s incredibly important.

Dr. Pahlajani: Absolutely. Thank you so much for having me.

Faith: Our many thanks to Dr. Pahlajani. I’m Faith Salie.

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