Erin Spain: I'm Erin Spain. This is Breakthroughs a podcasts from Northwestern University Feinberg School of Medicine this month a Northwestern Medicine study delivered some sobering news about heart failure. It found death rates due to heart failure are increasing, especially in people under the age of 65 and specifically among black men. What's fueling this upturn? How can it be stopped? Dr. Sadiya Khan, assistant professor of medicine and a cardiologist here at Northwestern led the study published in the Journal of the American College of Cardiology. She's here to talk about the results and share some answers to those questions. Thanks so much for being here today.
Sadiya Khan: Thanks for having me Erin.
Erin Spain: You have a long history here at Northwestern, not only as a physician, but you were a student here starting in Undergrad.
Sadiya Khan: Absolutely. I often will say that I bleed purple. I came here for Undergrad as a member of the honors program in Medical Education. Continued my medical training and then continued on to do my postgraduate internal medicine residency in cardiology fellowship. Along the way, I think one of the main reasons that I continued to stick around were the people that I met and it really is a testament to the community and the culture here about recruiting and retaining the trainees and being able to develop careers.
Erin Spain: We'll get to the specifics of this study shortly, but I wanted to ask you anecdotally, you spend your time between the clinic and the lab and I was wondering are you seeing an increase of younger people with heart failure in the clinic?
Sadiya Khan: This was one of the reasons that we were interested in looking at heart failure death rates in older adults and younger adults. Traditionally heart failure has been considered a disease of older age and we see in nationally representative data that the incidence or prevalence of heart failure tends to start increasing after the age of 60. However, in clinic we have seen many patients recently in their 30s, 40s and 50s that also are presenting with symptomatic heart failure and this led us to be concerned to see if there are differences among younger and older adults that are developing heart failure.
Erin Spain: So that was really a nugget to get you started on this particular study and just a little background about heart failure — it usually takes hold after someone develops something like coronary artery disease or high blood pressure. Can you just explain exactly what heart failure is and how it progresses?
Sadiya Khan: Heart failure is a difficult disease to diagnose? And that is one of the challenges. It's a complex syndrome. It's manifest by symptoms of shortness of breath, swelling or fluid overload and can have a reduced ejection fraction or impairment of the muscle function or a preserved ejection fraction. And these things make it very challenging for both doctors and patients to identify and diagnose it. Heart failure has many risk factors we've typically thought of as a disease that occurs after coronary artery disease, but we're finding more and more that the common risk factors of hypertension, diabetes, and obesity may be contributing more to the development of heart failure now than ever before.
Erin Spain: Can heart failure be reversed? Or once you have it, is it always something you're going to have to live with? And is it always deadly?
Sadiya Khan: So I think we have excellent medications. Over the past several decades, we've made significant progress in medical therapies and advances to help prevent morbidity and mortality related to heart failure. Therapies such as beta blockers, ace inhibitors, Spironolactone are excellent drugs. Even more recently, medications like Entresto have even more improved survival of heart failure patients.
Erin Spain: And there's about 6 million people in the US with heart failure and there's a major cost involved as well. It's the number one reason older people are admitted to the hospital. Can you just talk to me a little bit about the sheer numbers here?
Sadiya Khan: This is a very prevalent condition and even more important than the prevalence in the country is the morbidity associated with heart failure. Once someone is hospitalized for heart failure, the chance of being re-hospitalized in the next 30 days or year is extremely high and can be up to 50% and so the fact that recurrent hospitalizations when someone develops heart failure is an increasing problem, not only contributes to cost but contributes to quality of life.
Erin Spain: So reducing the number of heart failure deaths has been a goal for decades and progress was being made, but in this study you found that starting around 2012 there was a shift. Tell me about that.
Sadiya Khan: When we looked at the CDC wonder death certificate data for death certificates in the entire country, we looked at cardiovascular deaths related to heart failure and what we saw was that there was a decrease from 1999 to 2012, but in 2012 deaths started to increase. This has been previously studied as well by others looking at overall cardiovascular death rates and similarly in about 2012 there seems to be something that changed.
Erin Spain: The finding about more black males under the age of 65 dying from this disease is very troubling. Can you tell me about that and how you plan to follow up on this?
Sadiya Khan: Absolutely. What we saw was that in 2017 black men under the age of 65 were at 2.6 higher rate of having dying from heart failure and black women were at a nearly three fold higher risk of dying from heart failure compared to white men and women. While there are multiple reasons for this difference, some of the common ones may be related to underlying risk factor burden. We know that black men and women have a higher rate of having hypertension, obesity, and diabetes. There may be some other factors at play including access to care, having insurance and income.
Erin Spain: So you plan to follow up on this?
Sadiya Khan: Absolutely. We're looking at trying to understand what other determinants may be contributing to the mortality rates and the differential mortality rates between blacks and whites.
Erin Spain: So you mentioned the obesity epidemic and diabetes. Tell me a little bit about those and how they impact heart failure risk and does it have something to do with that 2012 spike?
Sadiya Khan: One of our theories is that the reason that there's been an increase since 2012 is the growing prevalence of obesity and diabetes in the country over this timeframe, both obesity and diabetes are independent risk factors for developing heart failure even in the absence of coronary artery disease and we know that these conditions are highly prevalent among patients who have heart failure with preserved ejection fraction especially.
Erin Spain: What happened in 2012?
Sadiya Khan: Yeah, that's a really interesting question and our data are not able to explain exactly why things changed in 2012. We know that the burden of obesity and diabetes has been growing for some time and maybe at that point the rate of deaths changed, but I don't know if there was a specific event that occurred in 2012 that could be contributing to why it happened, then.
Erin Spain: Well, obesity is definitely an area that you are an expert in. One of the main focuses of your lab is the influence of obesity on development of cardiovascular diseases and you've published papers on obesity. One paper published last spring debunked this idea of the obesity paradox and cardiovascular disease. Explain that idea to me of the obesity paradox and what you found.
Sadiya Khan: In certain chronic conditions like heart failure, chronic kidney disease, it's been studied and published that individuals who are obese that have heart failure or chronic kidney disease have a better outcome than individuals who have a normal BMI and this has been termed the obesity paradox. One of the important issues related to the measure of BMI is that oftentimes individuals who have heart failure, chronic kidney disease or other chronic conditions may have weight loss related to the disease and when they have a normal BMI it's not because they have a healthy BMI, but it may in fact be because of illness. This is really hard to tease out once people have disease. So one of the things we were interested in doing is looking in asymptomatic, healthy individuals before the onset of cardiovascular disease and look at BMI categories in terms of obese, overweight, or normal weight prior to the onset of cardiovascular disease. Follow these individuals over the next 10 to 30 years and see whether or not obesity conferred a protective advantage. Not unsurprisingly, it did not. Individuals who are obese are at higher risk of developing heart disease and they developed heart disease at a younger age and therefore lived longer with cardiovascular disease.
Erin Spain: So does this obesity paradox kind of throw that out the window now or people kind of over that idea?
Sadiya Khan: I think it remains controversial and in certain disease states one of the debates are in patients who have heart failure, who are obese is the recommendation that they should lose weight. Given that we don't have good evidence that individuals with heart failure who have a normal BMI, will have a survival advantage. I think stepping a little bit back, one thing that we know to stand true is that no matter whether someone has heart failure or doesn't, heart healthy measures like maintaining a healthy diet, engaging in physical activity as able, are the most important factors.
Erin Spain: And what is it about the obesity epidemic that draws you to study it?
Sadiya Khan: I think for me, one of the key interests was how prevalent the condition has become and in my clinic seeing so many patients who are now having complications related to their obesity including coronary artery disease, heart failure and stroke.
Erin Spain: So as you noted with heart failure seeming to be on the rise now — what are you doing in your lab to investigate this further?
Sadiya Khan: One of the key questions that this data raised for me and others is that are the death rates increasing because there's more people with heart failure or are the death rates increasing because heart failure is more fatal? And that's a really interesting question and I think to tease that out better. One of the things that we're now exploring is looking at national prevalence estimates and seeing if things have changed in the past 10 years over this same timeframe to see if some of the increases in the death rates could be related to an increasing prevalence of heart failure.
Erin Spain: So really is it just that there's that many more people being diagnosed with heart failure and that's what's causing this increase?
Sadiya Khan: That's my suspicion. I think we have made significant progress in terms of therapies for heart failure and overall the prognosis when someone is diagnosed with heart failure has improved compared to 10 years ago, but maybe there's just more people living with heart failure now and that's contributing to these trends.
Erin Spain: You know when the story hit the med Twitter world, a lot of cardiologists responded and there was kind of a collective 'boy, this is really sobering news and upsetting' because as cardiologists this is something you all work very hard on. What can patients and cardiologists do together to work on this problem?
Sadiya Khan: I think one of the other things that this data highlights is how much more efforts need to be focused towards prevention and identifying individuals who are at increased risk of developing heart failure and thinking about strategies to really prevent the development of heart failure. One possible strategy may be intensive blood pressure lowering. The SPRINT trial published a few years ago showed that intensive blood pressure lowering to a goal of less than 120 over 80 reduce the risk of major cardiovascular events and that was driven primarily by a reduction in risk of heart failure. I think there are some other exciting therapies that are on the horizon for patients such as SGLT-2 inhibitors, which is a new type of therapy for diabetes that has been uniquely shown to prevent heart failure among patients with diabetes in clinical trials who are receiving this therapy.
Erin Spain: And it sounds like this prevention is really going to have to start at a younger and younger age.
Sadiya Khan: Absolutely. And I think one of the things that we really need to focus on as a country is thinking about more primordial prevention and thinking about strategies to prevent the onset of obesity, high blood pressure, diabetes, and focusing on healthy diet and physical activity.
Erin Spain: And while this looked at obesity, and some of your other studies as well, just being overweight, not being at that healthy body weight is also a contributor. Can you talk a little bit about that? Because a lot of people in this country may not be obese, but they do fall in the overweight category.
Sadiya Khan: Absolutely. There's definitely been a lot of controversy about whether overweight is associated with worse outcomes as well. We've shown that overweight is also associated with increased risk of cardiovascular disease. The challenge of course is that BMI categories are standardized typically for white individuals and categories may need to be differentiated, especially among Asians where BMI cutoffs for risk of diabetes are far lower. So there are differences. In addition, it doesn't take into account muscle mass or fat distribution. So if someone is more muscular, their weight may still be categorized in the overweight category, but they may not be at increased risk. So each individual patient needs to have this discussion with their doctor about what a healthy weight for them is.
Erin Spain: It sounds like that's an area that's kind of prime for a makeover.
Sadiya Khan: Absolutely. I think as we are shifting and hearing more about personalized or individualized medicine, I think assessing individual risk for cardiovascular disease or heart failure in this topic is really important and thinking about what your weight is, what a healthy weight for you is. What's your blood pressure, what's your glucose level, and being your own advocate in this way as well and knowing your numbers.
Erin Spain: What excites you about going from the clinic to the lab and producing this kind of research that then gets distributed out to all of your colleagues across the country? Why did you make that choice to go into the physicians scientists world?
Sadiya Khan: I think the patients that I get to interact with and have the privilege to work with are what inspire me. When someone who successfully loses weight or is able to get their blood pressure under control. Those are the success stories that really continue to carry forward and help inform my work on why we need to think about prevention measures and focus on these areas of primordial prevention. The American Heart Association recently tagged a line called the life's simple seven to think about seven ways to help promote a heart healthy lifestyle. This is one of the things that I talk with all my patients about in clinic as well.
Erin Spain: So it sounds like we have a lot of work ahead on this topic.
Sadiya Khan: I think there's a lot of work to do, but I think there's reason to remain optimistic. We've got lots of new novel therapies to think about. We have to think about new prevention strategies, but I think there's definitely room for improvement.
Erin Spain: All right, well, we will be looking for more from you and more studies on this topic as well. Thank you so much, Dr. Kahn for joining me today.
Sadiya Khan: Thank you for having me.
Erin Spain: A note for physicians who listen to this podcast, you can now claim continuing medical education credit just by listening. Go to our website feinberg.northwestern.edu and search CME.