“...Asian are actually quite different in terms of health behaviors and cultural norms and values and immigration patterns and other social factors that may influence the health of people in each of these groups”
In this episode, Dr. Nilay Shah joins us to discuss the prevalence of cardiovascular disease, such as heart failure and ischemic heart disease, among Asian American subgroups. Dr. Shah sheds light on the specific groups of Asian Americans who are most affected by these conditions, discusses the “healthy immigrant effect”, and identifies some of the factors that may contribute to this health disparity in these sub groups.
Nilay Shah is a preventive cardiologist, and Assistant Professor of Cardiology and Preventive Medicine at Northwestern University. His research focuses on identifying and implementing strategies to help people maintain cardiovascular health and prevent cardiovascular disease, with a particular focus on supporting communities that experience cardiovascular disease disparities.
Shireen: In today’s episode, we are in conversation with Dr. Nilay Shah who joins us to discuss the prevalence of cardiovascular disease such as heart failure and ischemic heart disease among Asian American subgroups. Dr. Shah sheds light on the specific groups of Asian Americans who are most affected by these conditions. He discusses the healthy immigrant effect and identifies some of the factors that may contribute to health disparity in these subgroups. Stay tuned.
Dr. Nilay Shah is a preventive cardiologist and assistant professor of cardiology and preventive medicine at Northwestern University. His research focuses on identifying and implementing strategies to help people maintain cardiovascular health and prevent cardiovascular disease with a particular focus on supporting communities that experience cardiovascular disease disparities. Welcome Dr. Shah.
Dr. Shah: Thank you for having me.
Shireen: An absolute pleasure. Dr. Shah, just diving right in, can you share with us how being a cardiologist has really shaped your lifestyle habits and what you do differently in your daily routine that has really shaped the way you even practice medicine?
Dr. Shah: Thank you for that great question. So, as I learned more about heart disease and even more importantly about heart health, I became much more aware of how the environments in which most of us live work against us and don’t really position us for health success. And so, part of health and a part of heart health as I learned and trained in cardiology is the behaviors that each of us do, what we choose to eat and how active we choose to be. Whether we chose to smoke choose to smoke or not. Factors like that, but there’s a component of each of these decisions that is also a little out of our hands.
And, for me, that’s manifested most in the quality of the food that I eat. So, we all, especially here in the U.S., live in a food environment where we’re surrounded by fast options, food options that are really highly processed or designed to taste good, but aren’t necessarily designed to help us maintain our health.
And we’re surrounded by food marketing strategies that can train us to make choices that are less helpful. So, in, in my day-to-day, having trained in what I do and what I do in front of patients every day. Is to kind of try to reclaim some of that ownership of the decisions I make, especially with regards to dietary pattern.
I’m really mindful of the foods that I purchase in the grocery store and keep at home. I’ve learned to, and I now routinely read the labels of every item I purchase. If I dine at a restaurant, I’m looking up nutritional information on the restaurant’s website in advance. So, I’m better prepared to make a decision and a choice when I order.
And if a restaurant doesn’t offer nutritional information, I try to look at the ingredients of the foods or dishes that appeal to me. So, there’s an opportunity to make a better choice. And every so often I indulge too. Like I advise my patients and like I do, I’d like to make good choices about 80% of the time. I’m not aiming for a hundred percent because that’s just not how we live our lives. People have birthdays and special events and even are interested in trying new restaurants. But if I can make a good decision 80% of the time I, think that I’m in a good track.
And so that’s something that I really try to embody and live. Especially as I also advise the people that I meet to do the same thing, is to be really, really mindful of the quality of the foods that I’m eating in an environment that doesn’t necessarily set us up to be able to do that easily.
Shireen: Thank you for sharing that. And I think I do want to dig into that a little bit. But first I want to start things off with a study. So, you did a study in fact aimed at identifying cardiovascular and cerebral vascular disease mortality trends in Asian-American subgroups from I believe, 2003 through 2017. So first off, can you define what cerebral vascular disease is, and then can you share with us this relationship between the two? And explain that a little bit more to us.
Dr. Shah: Yes, of course. So, this study you’re alluding to looked at patterns of cardiovascular and cerebrovascular disease, as you said over the last two decades here in the U.S. and specifically in Asian subgroups. So, to start with, when I say cardiovascular disease, what I’m largely talking about are diseases that affect the heart.
So, heart diseases, like having a heart attack or having a condition called heart failure. And when I say cerebral vascular disease, what I’m referring to are diseases that affect the health of the brain. Most commonly things like a stroke are what we mean when we talk about cerebral vascular disease.
And this study specifically looked at patterns of the rates of mortality or the rates of death from these two types of disease. And the reason we look at them together is because there’s a pretty close connection between cardiovascular disease or heart disease and cerebrovascular disease or brain disease.
Both of these organs, although they operate and they work in really different ways, are affected by the same kinds of health factors because the heart and the brain both have a really important supply of blood and have a lot of blood vessels. And when we talk about cardiovascular and cerebrovascular disease, we’re talking about conditions that affect the health of the blood vessels that supply these organs.
So, for example, a heart attack is a disease of the blood vessels that supply the heart. A stroke is a disease of the blood vessels that supply the brain. And so, these two types of conditions are really closely linked. If somebody has heart disease, they’re at higher risk for having a stroke or a brain disease.
If somebody’s experienced a stroke, they’re at higher risk for experiencing a heart attack or heart disease. And a lot of the factors that contribute to risk for both are very similar.
Shireen: Does having risk for one heightened the possibility of risk for the other? And what is that proximity and time that we’re talking about there?
Dr. Shah: So, yes, the, having experienced one can increase the possibility of another. The timeline is a little bit challenging in that really if somebody has a history of heart disease, they likely will remain at a higher risk for cerebral vascular, or brain disease for their lifetime. And the opposite is also true, but the good news there is that the risk factors for either, the risk factors for heart disease and the risk factors for brain disease are very similar.
And they are addressable. Both of these types of disease are preventable. When we talk about risk factors, we’re talking about things that probably a lot of people have already heard of. Things like high blood pressure and smoking and high blood sugar or diabetes. Eating a healthful diet and staying physically active or getting exercise. All of these are factors that can contribute to the health of the heart and the health of the brain, and optimizing all of these factors can reduce your risks for experiencing either heart disease or brain disease.
Shireen: Getting into that a little bit, in this research that you did, you noted that it is risky to generalize Asian health and I’m so glad that you’ve mentioned that. Specifically generalizing Asian health into a single category due to the diversity of the subgroups within the Asian population. Can you elaborate a little bit more on how categorizing Asians. Into one group prevents our understanding of these health risks.
Dr. Shah: Yes. Thank you for that important question, which is a very strong focus of the work that I’m trying to do. The Asian American population is not uniform. For a long time when health related research was done, people who identified as Asian or Asian American were grouped into one category called Asian.
I think on one hand, many of us who identify as Asian, probably from the outset knew that probably was not accurate. But the environment of health research is really only recently catching up. Because I think it’s pretty clear to people who identify as Asian and increasingly clear to people who may not identify as Asian, that the different groups of people that are.
Otherwise labeled as Asian are actually quite different in terms of health behaviors and cultural norms and values and immigration patterns and other social factors that may influence the health of people in each of these groups. So, when we talk about Asian subgroups, one of the most common ways to subcategorize the Asian population is by their ancestry or their country of origin.
For example, groups such as Indian or Chinese, or Filipino or Vietnamese or Korean, which are some of the largest Asian subgroups in the United States. All have actually very different social factors or social determinants that contribute to their health. Things like educational attainment or socioeconomic position or cultural norms regarding protection of health.
And similarly, behaviors that influence health can be very different. And the one that kind of the leading one that comes to mind is probably dietary patterns. Which is a, actually a very complex health behavior that is influenced by social norms and religious affiliation, which differs across these Asian subgroups.
And so, we’ve come to learn that when you aggregate, or you combine people from different Asian subgroups into one category called Asian. You actually miss and lose a lot of the variability in health status and health outcomes within these groups that is masked by putting everybody into one group.
And when you separate out these groups, there’s a fairly wide range of health status and the burden of health outcomes that is seen. And if we really want to better represent and address the opportunities for health promotion and disease prevention in these groups, we have to know where we start.
And so that starts with understanding how individuals in the Asian group might identify themselves and how that might relate to differences in health status and health outcomes across these groups.
Shireen: And sort of this well generalized approach that can hamper some of that progress that can be made in these specific groups as well, I assume.
Dr. Shah: Well, and that’s actually, I think what the real concern about aggregating groups in research actually is. Is that beyond just missing some of the variability, it may actually hinder the efforts to support the health of this rapidly growing population. And just to give some context to one reason why this is important. The Asian American population is the fastest growing group of minoritized individuals in the United States, and by the year 2050s expected to be the largest minority group in the United States after the non-Hispanic white population. And so, this population in the U.S. is growing rapidly and is very rapidly going to come to an important forefront in understanding how to protect their health.
Shireen: And so, differentiating them now gives us the opportunity to set things up for the future and be able to better address their needs as well.
Dr. Shah: That’s exactly right. And part of that is that when we think about health and the promotion of health, it is a life course approach that I think allows anybody, whether they’re identified as Asian or not, to protect their health. And by that, I mean as I think probably a lot of people understand health is something that is relevant to all of us at any stage in life.
There, isn’t a switch that flips where we can disregard things related to our health and then start paying attention to that. If we were all to take a perspective in which we were focusing on or putting priority on our health, starting from a young age, I suspect that for all of us across our lifespans, it would pay off.
Shireen: I love that. I do want to switch gears back to a little bit on the heart disease side. Some specific cardiovascular diseases that you highlighted in this article. One specific one is ischemic heart disease and heart failure. Can you break down both of these to give us an understanding of what they are and then specifically their causes?
Dr. Shah: Yes, absolutely. So first ischemic heart disease, which is the most prevalent or the most frequent type of heart disease experienced by anybody in the United States and across the world. So ischemic heart disease is really just a technical or a fancy way of saying something like, heart attack or blocked heart arteries.
What ischemic heart disease means is that a condition has occurred in which the heart muscle is not getting enough blood flow. That is the definition of ischemia. And when that happens suddenly or rapidly, that can manifest as a heart attack. But ischemic heart disease can also happen slowly.
People can develop blockages in their heart arteries because of plaques that have deposited in those arteries over time and slowly start to develop a condition in which their heart does not get enough blood flow. So, this spectrum of decreased blood flow to the heart muscle, whether it’s slowly over time or whether it occurs rapidly within the course of minutes or hours, as in the occurrence of a heart attack is one of the most common ways that heart disease manifests.
And heart failure is a related, but actually also somewhat different type of heart disease. So, heart failure is also a little bit of a misnomer. It doesn’t necessarily mean that the heart is failing, but most commonly it means that the heart is not working as well as it should. The heart is a pump, and it pumps blood to the rest of the body.
And there are many potential causes for why the pump may start to deteriorate or not pump blood as well to the rest of the body. As it turns out, one of the most common reasons for heart failure or a decrease in the heart function or the pump function is because the heart muscle is not getting enough blood flow. So, there is a relationship between ischemic heart disease and heart failure, but there’s a whole other bucket of heart failure as well that is not due to blockages in the heart, arteries leading to decreased blood flow of the heart muscle.
And that’s a very heterogeneous or complex set of conditions that can include inherited conditions because of genetics that include conditions that affect the health of the heart muscle because of external factors like heavy alcohol use. There is a fairly complex set of potential causes to heart failure and, ischemic heart disease is just one of them.
Shireen: And going back to what we were talking about, different groups as well, can you share with us some of the findings such as, which groups experienced a higher burden of ischemic heart disease?
Dr, Shah: Yes. So, these were actually some of the leading findings from this research study.
We learned that among the six largest Asian American subgroups, which again are Asian, Indian, Chinese, Filipino, Korean, Japanese, and Vietnamese. Among those groups the highest mortality rates from ischemic heart disease were experienced by people who were Asian Indian. So, Asian Indian women and men experienced the highest mortality rates from ischemic heart disease and also experienced the highest mortality rates from heart failure.
This is a pattern that has come to be recognized perhaps over the last few decades. That people who identifies as South Asian, so have ancestry from South Asian countries, including India, tend to have a higher proportion of death that occurs from heart disease and have higher rates of death that occur from heart disease.
And it was somewhat alarming that in contemporary data. So, mortality statistics from the United States over the last two decades. We confirmed and saw that the Asian Indian, or the Indian population, Indian American population, had the highest mortality rates from these leading causes of heart disease in the U.S.
Shireen: So being a South Asian female myself, it’s a little bit alarming. So, let’s get to the factors that contribute to the higher rates of ischemic heart disease in this group.
Dr. Shah: That is very much an active area of study, but a couple of patterns have emerged out of the research that’s being done. There does seem to be a disproportionate impact of high blood sugar, or in other words, diabetes in the South Asian population, both women and men.
Some of the research that has recently come out suggest that there is a role to body composition in the South Asian population. So, for example, when fat deposits in the bodies of people who are South Asian, it tends to deposit less under the skin and more into the organs of the body. And it’s been learned that this is a higher risk form of fat deposition.
That may in part be related to dietary pattern but may also not be related to dietary pattern. And, I say that because there are potentially some factors that are outside of people’s control. That leads to particular accumulation of fat in visceral organs, or in other words, the term has been used visceral fat.
That contributes to the risk for diabetes and the risk for heart disease in South Asian women and men. And the role of diabetes in South Asian individuals seems to be a particularly strong point that has emerged.
Shireen: Interesting. I do want to talk about that a little bit more. I do want to switch gears a little bit to heart failure and again, talk about groups that experience a higher burden of that. Can you break that down for us as well?
Dr. Shah: Yes. So, the patterns were a little bit different for, well, actually. Sorry. With heart failure. Yes. The burden also was seen to be highest in women and men who identified as Asian Indian. And I could speculate a little bit about that, but I would speculate that that pattern emerged in part because of the high burden of ischemic heart disease in this group.
So, you may remember a few moments ago I mentioned that ischemic heart disease is one of the leading contributors to heart failure as well. And so, because people who are Asian Indian in this group, experienced the highest burden of ischemic heart disease.
I suspect that’s also why they experienced the highest burden of heart failure. And I’m just going to take a very brief aside here just to point out the fact. If somebody’s listening to this and they wonder, well, I am South Asian. I came from a South Asian country, but I’m Pakistani, I’m Bangladeshi, I’m not from India.
Does this still apply? And that’s an important question that I will say we don’t yet really have an answer for. And the reason is because the way that health statistics are collected in the United States hasn’t really yet caught up to the way that people actually identify themselves in the United States.
And so, by that I mean a lot of the ways that we collect health data in this study, for example, looking at death certificates from people who passed because of heart disease. Don’t really allow for the identification of people who are, for example, Pakistani or Bangladeshi or Sri Lankan. And that’s a really important limitation.
Because I think it probably is not a surprise to say that not every South Asian is Indian. I mean, that’s actually kind of obvious, but the way that we collect health statistics in the U.S. hasn’t yet caught up to what our understanding of identity actually is in the South Asian or other Asian population.
Shireen: And so far, from what you’ve mentioned, not a good day to at least be a South Asian person listening to this podcast.
Dr. Shah: Well, I’m not sure I would quite go so far because although there is some concern about the risk of heart disease in this group. On the other hand, I think favorably a lot of this excess risk experienced by people who are South Asian is largely addressable and preventable. And so, although there, it is fair to say that being South Asian itself likely enhances somebody’s risk for experiencing ischemic heart disease or heart failure That risk is not insurmountable. So that there is some positivity to that.
Shireen: And let’s get into some of that. What do some of those things look like today? As you work with yourself work with groups and people within those groups. What are pieces of information that you can provide to them that helps them lower their risk of these conditions.
Dr. Shah: So, when we think about addressing and lowering the risk of any type of heart disease, whether it’s ischemic heart disease or heart failure, or brain health and brain disease like strokes. It is important to really anchor on the leading risk factors for these conditions. So briefly, those are things like dietary pattern exercise and physical activity, smoking or actually not smoking.
Body composition and body weight. And then some of the factors that you sometimes talk about when you meet your doctor, like cholesterol and blood pressure and blood sugar or diabetes. And then recently, it’s actually come to the forefront that sleep health also strongly contributes to heart health and brain health.
And so, these eight factors tend to be the leading risk factors for any type of heart or brain disease. And as I think you can probably start to imagine there are ways to address or optimize the health of all of these factors. And so, when it comes to things like dietary pattern, being really mindful, as we alluded to earlier in our conversation about the quality of the foods that you’re eating.
When I meet a patient and I have a limited amount of time to advise them about optimizing their health. The things that I really focus on are my recommendations are to follow a largely plant-based whole food, minimally processed diet. And so, we’ve learned a lot about the risk for chronic disease and heart health and heart disease associated with consuming animal products.
And I don’t advise that anybody necessarily has to go fully vegetarian or vegan, but what I say is, if you are consuming an animal product to choose a leaner cut or a lower fat version, so in the terms of poultry, for example, choosing cuts of meat that don’t have skin have the skin removed. Are focusing on white meat as opposed to dark meat. When choosing red meats like beef, choosing leaner cuts and removing and trimming any excess fat you might see in preparation of foods. When consuming dairy like milk or yogurt.
Choosing lower fat forms can help reduce some of the risks associated with consuming animal products. But still focusing on a largely plant-based diet. So, maximizing intake of fresh fruit and vegetables when having grains, prioritizing whole grains, and being really mindful of two things that likely contribute pretty significantly to heart disease risk, which are saturated fats which are found in foods that are highly processed or fried.
And cholesterol, which the only source of dietary cholesterol is in animal products. You won’t find a cholesterol in plant-based products. And so that is part of the reason underlying a recommendation for a largely plant-based diet. Things like finding opportunity to increase physical activity.
And I don’t ever really recommend anybody go from not doing any physical activity to running a marathon. That is neither necessary nor realistic, but doing things that are easily attainable and don’t really require a large shift in people’s day-to-day lives. I think people actually really strongly discount the value of walking.
Walking is spectacular exercise. It really doesn’t take very much. To start to support the health of your heart and your brain and your lungs and the rest of your body. And my minimum recommendation is that anything is better than nothing. So, if your measurement of physical activity goes from zero to anything greater than zero, you’ve already achieved more than most people are doing.
So, it really doesn’t take very much. And we could talk a lot about all of these factors, but These are some of the ones that I think are most likely to help people move towards better heart health.
Shireen: There’s one more quick question that I would like to sneak in here before we wrap up the episode. Especially as you were talking about the origins of where people are, from where they originate, be it India or Pakistan or different countries. We often hear about the healthy immigrant effect in Asian self-groups where immigrants tend to have better health outcomes compared to their U.S. born counterparts.
How does this impact cardiovascular disease risk and mortality rates and the challenges in studying this phenomenon?
Dr. Shah: That is a really important question, especially because approximately 50% of people in the U.S. who identify as Asian are immigrants. And so, it is actually a very heterogeneous group.
There’s a growing proportion of U.S. born people who are Asian or from other countries and about half of them are immigrants as well. So, I’m going to start by saying I’m a little bit of a skeptic of the healthy immigrant effect. So, it is true that observational data and, and data on immigrant populations do suggest that people who identify as Asian, for example, who are immigrants, tend to have better health.
That observation, I think has been seen time and again, but I have a little bit of a nuanced thought on why that pattern is seen. I think we have to really carefully consider. The reasons for immigration and immigration as a social determinant of health.
Part of the healthy immigrant effect may in fact be due to the fact that there is a little bit of what is called a selection bias. In whom immigrated and whether the factors that led to their immigration were actually also factors that supported their health. The bulk of. Immigration from Asian countries happened after the Immigration and Naturalization Act of 1965.
And I won’t go too far into the history, but after that, that law was passed in the U.S. there was much more immigration from Asian countries and from all countries outside of the U.S. But a lot of the immigration was limited to people who were otherwise already had high educational attainment or socioeconomic position or were in a position to come to the U.S. because of educational opportunities or employment opportunities.
So, these were people who were starting with relatively high socioeconomic position. And we know that socioeconomic position is a really strong driver of good heart health because having a high socioeconomic position, having financial means and educational attainment helps people maintain their health in a lot of different ways.
One way, for example, is knowing what to consume that’s healthy. One way is being able to afford healthful foods like fresh fruits and vegetables. Which are not always affordable and is a strong barrier to potentially maintaining a healthful dietary pattern. So because there was a selection, especially in early stages of immigration to the U.S. of people who had relatively high economic opportunity and socioeconomic position.
That likely resulted in a group of people who were also more helpful at baseline because they had the opportunity to be more helpful. And then as the years passed, as these individuals who were highly educated and had high socioeconomic position established themselves in the U.S. and started bringing more of their families to the U.S. The health of the immigrant population in the U.S. has started to have much more diversity because you know that that initial group of people who are at high socioeconomic position likely had fairly good health.
And then over time, people who immigrated, but who were at lower socioeconomic position or who were able to immigrate to the U.S. following individuals. Who were kind of like the vanguard of the group of immigrants. Who came to the U.S. likely had less healthful health behaviors or had more variability in their health outcomes.
And so there may have at times been a healthy immigrant effect, but I do think that the health of the immigrant population is much more diverse and variable than it once was.
Shireen: That is so interesting and also layered, right? Because like how do you draw that line from the immigrant coming and then the generations after? And so, lot of work and lot of sorts of differences there to study still it sounds. With that Dr. Shah, we are to the end of the episode at this point. Can you tell our listeners how they can connect with you and then just learn more about your work?
Dr. Shah: Yes, of course. Well, you can find me on Twitter. My Twitter handle is @NilayShahMDMPH. You can search for me on Google and contact me through email there as well.
Shireen: Perfect. Well, thank you so much, Dr. Shah, for your time. To our listeners, we are toward the end of the episode, but we do want to continue the conversation with you. Head over to Facebook, our Instagram page and find this podcast post and comment below with this easy-peasy question. How have you or someone you know, experienced heart disease or heart failure, and how has it impacted your life or that of your loved one? We would love to hear from you, share your stories, your perspectives with us.
Again, we’ll keep the conversation going on Facebook, on Instagram. Find us at Yumlish. Excuse me, just losing my voice toward the end of the episode. Find us over there at Yumlish and we’ll continue the conversation there. And again, Dr. Shah, thank you so much for your time.
Dr. Shah: Thank you for the opportunity.