Transcript
Matthew DeVane, DO FAAC: [00:00:32] Hi, I'm Doctor Matt DeVane.
Carolyn Lacey, MD FACC: [00:00:34] And I'm Doctor Carolyn Lacey. We are cardiologists at John Muir Health and this is our podcast, Living Heart Smart.
Matthew DeVane, DO FAAC: [00:00:40] Our physician partners and colleagues are going to help guide you through many different and important cardiovascular topics to help keep your heart happy and healthy.
Carolyn Lacey, MD FACC: [00:00:48] Thank you for listening and we hope you enjoy our show. Hi everybody. Matt, you and I are here today with another with one of our partners, Doctor Jason Liu. We've all heard him talk before. He talked about your cardiovascular risk. He's back with us today. We're going to be talking about cholesterol testing. I don't know if I don't know, Matt. Do you remember that Jason and I, we both went to the same medical school at Drexel University. I do.
Matthew DeVane, DO FAAC: [00:01:13] Remember you saying that at different times.
Carolyn Lacey, MD FACC: [00:01:15] Of course, but.
Matthew DeVane, DO FAAC: [00:01:16] Yeah, I won't comment anymore.
Carolyn Lacey, MD FACC: [00:01:19] Yes, stop. But, Jason, when I was in medical school, they had these homeless outreach clinics that we did in Philadelphia. Yeah. Did they have that? Did they still have that when you went to Drexel?
Jason Liu, MD: [00:01:30] Yeah. They do. You know, a lot of us were sort of, uh, had different roles. And for me, I had to I did these mindfulness, uh, courses, uh, with the patients who were recovering from drug use, um, and who it's interesting. I mean, you have a whole crowd of people. Everyone's eyes are closed. You're walking them through, like, a little, uh, mental story. Mental picture. You're ringing a bell every now and then.
Carolyn Lacey, MD FACC: [00:01:59] We didn't do that when I was in medical school. And we. And we did call it the homeless Outreach clinic. We didn't call it unhoused. That wasn't around at that point in time.
Matthew DeVane, DO FAAC: [00:02:07] What an experience.
Carolyn Lacey, MD FACC: [00:02:08] So did you ding the bell?
Jason Liu, MD: [00:02:09] Absolutely. That's that's the best part of the.
Carolyn Lacey, MD FACC: [00:02:11] That was the best part. Atherosclerosis is one of those things that it's it's our number one killer in atherosclerosis is a major process. That's when we when we talk about coronary artery disease. And cardiovascular disease is still the number one cause of death in the United States. Up to 49% of adults have some form of cardiovascular disease. And while our death rates, thankfully over the last 30 years or so, have dropped from one and 2 to 1 and eight, that just means that more people are living with coronary disease as a chronic condition.
Matthew DeVane, DO FAAC: [00:02:45] People are living longer, but they're living with more disease, right?
Carolyn Lacey, MD FACC: [00:02:47] Right. And a big part of this condition is lipid management.
Matthew DeVane, DO FAAC: [00:02:52] You let's, let's, let's get into some patient stuff. And what what is cholesterol. Why do we need it. Why are we checking it and why is it, you know, for so important for us as cardiologists.
Jason Liu, MD: [00:03:01] Yeah, absolutely. First and foremost cholesterol. It's it's a system that's in place. It's preserved across all mammals. It's a way of distributing energy, of recovering energy. And we need it, right? We need it. The only issue is that now you're kind of living in a society, a modern society with a modern diet. Um, where we have there's sort of a relative nutrient abundance. Right. And so let's start by asking the question, what is normal? Right. What is normal cholesterol. And so first of all, let's just talk the averages right. The average LDL, someone has a heart attack in the United States is 130mg per deciliter. Right? Right. And so now let's let's backtrack. There's this beautiful paper that came out in the early 2000, uh, by O'Keefe. And in that paper he talks about hunter gatherer populations around the world, pygmy Inuit. In addition, he also looks at serum cholesterol in mammals around the world, primates and other mammals as well. And believe it or not, if you look at the the LDL for these hunter gatherer populations, they're between 50 to 70. And amongst across all the mammals, humans are the only mammals with ldls greater than 80. So what is normal? Is it less than 130? Is it less than 100 that we peg it to be? Nowadays? No, it's it's you know, nowadays we'll talk about a little bit more, but we target goals based on the patient's risk. But you can see how far out we are from what most likely is your natural LDL. I think you mentioned at one point that the LDL of a of a child, a newborn. Yeah.
Matthew DeVane, DO FAAC: [00:04:42] I think is 30, right. Yeah. You're born with an LDL of 30. And then the average, you know, 50 year old person in this country has an LDL of, you know, 131 4150 right.
Carolyn Lacey, MD FACC: [00:04:52] I do think it's important to remember that we've sort of taken the average and we've normalized that and said this is normal. Average doesn't mean.
Matthew DeVane, DO FAAC: [00:05:01] Normal. That's a good point, right?
Jason Liu, MD: [00:05:04] Very good point. Um, and so what you found was that as the mean and median LDL levels came down, the event rates also came down. And so if you look at the Marsden paper basically showed that there's a log linear event reduction as LDL comes down. So as LDL comes down, there's a log linear decline in the number of cardiovascular events. So you know, nowadays, you know, we focus a lot of our medical management on targeting LDL, getting it to a certain goal. And we'll talk about those in a little bit as well. Now in the traditional lipid panel, you know, two other molecules that feature HDL and triglycerides I love HDL. Um, I.
Matthew DeVane, DO FAAC: [00:05:50] Used to love it. Now I used to love it. Mixed relationship with it. I'm not sure.
Jason Liu, MD: [00:05:54] It pulled an Anakin on me. I, you know, HDL, the role of HDL. It's beautiful by design, right? In an era when we didn't have enough nutrition, you needed a mechanism for for the body to to send a molecule out, gather up unused cholesterol and bring it back to the liver, to be made into hormones, be made into bile. Right. So HDL functions and what we call reverse cholesterol transport. But what we later learned is that everyone's HDL operates at different efficiencies. We had drug therapies that raised HDL and that never resulted in better cardiovascular outcomes. And so the whole the whole idea that, you know, HDL compensates for LDL, I think is out the window at this point in time.
Matthew DeVane, DO FAAC: [00:06:42] Yeah, I feel terrible because, I mean, for the last 20 years, I've called it good cholesterol. And the higher it is, I think was thinking in my mindset was the more you're protected. Right? And that's just not the case that That.
Carolyn Lacey, MD FACC: [00:06:53] Hasn't been shown.
Jason Liu, MD: [00:06:54] And that's and that's the beauty of the I mean, that's why I love about cardiology the fact that all this information is, is coming out and we're constantly redesigning and rethinking what we know. So, you know, if you're in terms of targeting numbers, you know, HDL, triglycerides, they never they never panned out to to what we hoped they would be. Um, although I still hope for HDL.
Matthew DeVane, DO FAAC: [00:07:19] Triglycerides are part of the standard traditional lipid panel, but I do get a lot of questions from patients. What is a triglyceride? And is that as dangerous as your LDL cholesterol?
Jason Liu, MD: [00:07:29] Um, so triglycerides, uh, what they are, they are a source of energy. And by that I mean they are fatty acids, right? Fatty acids that we get through our diet in saturated fat gets broken down and then repackaged as triglyceride molecules. So triglycerides, they can be impacted by a lot of things, but especially, you know, diets that are heavy in saturated fats, processed foods. And so we see them being very elevated in patients who may not have a good diet. And it's actually one of my ways of telling if someone's changed their diet after starting medications.
Matthew DeVane, DO FAAC: [00:08:09] That is the one, uh, component of the lipid panel that is very much in the patient's hands because they can make lifestyle changes and you see those triglyceride levels come down.
Jason Liu, MD: [00:08:20] Yeah. And the the thing the same thing holds true for triglycerides as it does for HDL. Basically there are therapies that we've derived to treat triglycerides, but we never found any consistency. Right? Where there's a treatment that treats that lowers triglycerides significantly but doesn't result in any improvement in outcomes, versus some therapies like Vascepa, which have a mild to moderate reduction in triglycerides. That has more benefit right now. The thing is that the way that we use triglycerides, we consider a risk modifier. And so patients who have triglycerides greater than one 75mg per deciliter, we consider that as a marker of risk. And that is in part a reflection of potential lifestyles that may be contributing to high triglycerides. And so yeah.
Matthew DeVane, DO FAAC: [00:09:12] Yeah, I like the way it could contributor to risk. I think that's a good way to put it.
Carolyn Lacey, MD FACC: [00:09:15] So we've talked about a little bit that we're getting the we're measuring the HDL. We're measuring the triglycerides. We calculate the LDL from our plain old lipid tests. And there's also the LDL. Can you can you tell us I don't usually it's normal. So I don't know what to do with this.
Jason Liu, MD: [00:09:36] So I'll I'll tell you a little bit the story about because VLDL and LDL are are part of the story of why we have LDL in the first place, right? Um, there needs to be a way for our body to transport energy molecules, basically triglycerides. Right? And fatty acids that can be transported to muscle to your heart. Mhm. So the organs that need that need energy to to generate an output. Right. And so VLDL is the very is the very first molecule that that is the transport. Right. It's there to collect triglycerides in addition to the triglycerides. There's some cholesterol esters that come in with it. And then the VDL VLDL gets shipped out. The very low density lipoprotein goes out in the bloodstream and starts to circulate and distribute triglycerides to the rest of the body. And as it the distributes these triglycerides, the molecule becomes smaller and smaller and smaller. And then you get to your intermediate, and then you get to your LDL, your low density lipoprotein. And so there's not a lot of a lot of analogies for what LDL really is. And it really it's just an it's an empty tanker at that point in time. Right. It served its purpose. And then it becomes the job of the liver to recapture that and recycle it. Um, but the problem is, it's so abundant because the diets that we have now, um, that they're lingering in the blood longer. Right? And, um, of course, the longer LDL lingers in circulation, the smaller and smaller it becomes. And then at some point in time, right, um, there is going to be some injury to the arterial lining artery being the the pipes that carry blood around your heart. There's going to be an injury to that artery and then that LDL is going to stick to it. Yeah. And then accumulate and develop into plaque.
Carolyn Lacey, MD FACC: [00:11:31] Develop into plaque.
Matthew DeVane, DO FAAC: [00:11:33] It's a complex process beyond that. But the the initiating fact really is as an arterial wall that becomes semi damaged or permeable for some reason, and then LDL sticks in it and starts working its way through. Right.
Carolyn Lacey, MD FACC: [00:11:48] We've already talked about a lot of those things that can cause arterial damage. But I think the other thing that's really important to talk about is that this process, this damage, this this starts from early life. And the first form of atherosclerosis is the fatty streak. Or we talk I remember learning about this in pathology class where you have young arteries that have small amounts of atherosclerosis starting to build up. And that starts in our 20s in the United States. So it starts really early. We think that it's not really starting until our 30s and 40s, but that's not accurate. The last part that we measure on our standard lipid panel, the fasting lipid panel that you see calculate out on your on your lab results when you get them back on your my chart is the ratio I used to use the ratio when I was young. When I was very young, I used the ratio of your ratio when I was a baby cardiologist. When you got the ratio and your ratio was very low, and the ratio is your total over your HDL. And if your ratio is low doc I'm good. My ratio is so good. That's that's changed for us a little bit hasn't it. Can you tell us. Oh yes.
Jason Liu, MD: [00:13:05] Yes it's absolutely changed. And I think as we start to realize again like um, HDL particles, the, the protective benefits of HDL really depends on the efficiency of the HDL And what we've seen is that, you know, is the reason that our HDL levels are high is because they're being efficient, or are we not? Or are we just not clearing them? And that's where we run into an issue, right? The liver's job is to also clean up the HDL. But in reality, the high HDL can be HDL. That's just not efficient at doing its job. And our bodies are not efficient at processing the HDL. And so that's why the HDL ratio is largely been abandoned.
Matthew DeVane, DO FAAC: [00:13:47] Yeah, I agree, I'm not using the ratio really at all for clinical purposes.
Carolyn Lacey, MD FACC: [00:13:50] And we used to give it a pass for the LDL. But now I've really come back to telling patients that we don't use that. And it all does come back to the LDL. Nothing gives the LDL a pass. Really. All right.
Matthew DeVane, DO FAAC: [00:14:04] Jason, I think that was a fantastic review of the traditional lipid panel. I think today we're thinking about lipids a little bit differently. And we've talked about this talk. The modern approach to cholesterol testing. And I think a couple of the new things that we're looking at, they're not brand new, but things that were focusing more now on checking in our patients or things. A couple things I want to talk to you about. Number one is the non-hdl cholesterol. And number two would be something called an apolipoprotein B. So if you wouldn't mind telling me what those labs are and how patients should be thinking about it, should everybody be getting those at this point?
Jason Liu, MD: [00:14:38] Yeah. So my take on it, on Apob, for example, is, is this, you know, we've had the lipid panels which, which looked at multiple different lipoproteins, right, LDL, HDL. But is there a way to just sort of quantify the ones that actually contribute to risk? Ap does the job, right. And so all of the molecules that could potentially form plaque, LDL, the LDL, IDL, as we'll talk about soon, lipoprotein little a these all express apob. And so apob then is a direct measure of everything that's bad. Right. And then we could get rid of the of the confusion, you know, for example, from HDL and triglyceride levels.
Matthew DeVane, DO FAAC: [00:15:26] And I think there are some proponents now that said, everybody should have the apob as the main measurement that we should be focusing on treatment. Right?
Jason Liu, MD: [00:15:34] Yes. And the challenging thing being is that the a lot of the, the modern trials were designed based on regular.
Matthew DeVane, DO FAAC: [00:15:44] Ldl LDL right.
Jason Liu, MD: [00:15:45] And so I do think this is something that is going to be incorporated into practice, probably into clinical clinical trial design and down the line. But yeah, we'll.
Matthew DeVane, DO FAAC: [00:15:54] See how things go. What about the non-hdl cholesterol. Can you comment on that.
Jason Liu, MD: [00:15:57] So non HDL then is you know referring back to the the the traditional lipid panel is essentially total cholesterol and then subtracting out the HDL, which is not a direct measure of it's not a direct measure of other atherogenic lipoproteins like Apob is, but gets closer.
Matthew DeVane, DO FAAC: [00:16:20] Jason, you just were mentioned in your discussion there about lipoprotein B and non-hdl cholesterol, something called lipoprotein little A or LP little A, as we also call it. And I think this is a very, very exciting piece of, uh, kind of new news that we're all looking at in more depth now. I'm checking in on every single one of my patients, whereas before it never, hardly ever got checked. So can you tell me about the lipoprotein little A and where it falls into cardiology today.
Jason Liu, MD: [00:16:50] So lipoprotein little A is one of the apob expressing lipoproteins. And what's important to know about lipoprotein A is that it is purely inherited. So and the levels of lipoprotein little A are largely outside of your control. Okay. And so if yours are high, it's mostly been high ever since you were ten years old. If yours is low, it'll never be high. So it's really important to test for this because it it's, you know, especially for those patients who I see a strong family history. Um, because what's humbling about it is that there's no treatment for it. The treatments that are are going to appear in the next 3 to 5 years. Many of them are all in phase three trials. And so when I see a high LP, Lily, you have to realize that lipoprotein little A is almost six times as harmful as LDL. Yeah, I think of.
Matthew DeVane, DO FAAC: [00:17:48] It as an LDL on steroids, almost. I mean, it's super nasty.
Jason Liu, MD: [00:17:51] Exactly. And it contributes to stroke risk, heart disease risk, as well as peripheral arterial disease. When you see a high lipoprotein little A, it means that we need to be much more aggressive with the other risk factors that we could potentially treat.
Matthew DeVane, DO FAAC: [00:18:07] I know you just mentioned that that certainly people with a strong family history of coronary heart disease or stroke or atherosclerosis need to have an LP. Lily, but I think the data shows that about, uh, only 1 or 2% of the population is being screened for this, whereas up to 20% of people actually have it. So my philosophy these days is to check everybody whether or not you've got a family history of coronary disease or not. Let's get it. Because it's a one time deal. You check it and you're done.
Jason Liu, MD: [00:18:34] Exactly right. Exactly.
Matthew DeVane, DO FAAC: [00:18:36] It's so easy to do if, um, if you haven't had your LP little late checked, please talk to your doctor about how that can be done.
Carolyn Lacey, MD FACC: [00:18:43] We've talked about Apob. We've also talked about LP little A, but we haven't really talked a lot about those advanced lipid panels. And I'm seeing a lot of patients coming into the office that have had the NMR lipid panel, the Berkeley heart panel. I think there's a Boston heart panel myself. I'm generally not ordering. Those. Are you are either of you ordering those tests?
Jason Liu, MD: [00:19:09] I don't I don't order them often as well. I like to remind the patients it's sort of like a little bit of an it's an academic knowledge. Right. It's nice to know, like, you know, the size of your, you know, lipid particles, the size of your ldls. That gives you an idea of the dynamics. Right. Um, um, the only things I really pull out of that, that advanced lipid panel ultimately, is going to be the LDL, apob lipoprotein, little a and and because those are the things that we know impact risk and and is there any utility in advanced lipid panel in terms of guiding therapy? Not so much, because all of our advanced cholesterol therapies have always been based off of LDL.
Matthew DeVane, DO FAAC: [00:19:53] I think the thing you said there is key is, is not going to really advance our therapy in any way. And also, there's no data to suggest that events are driven by some of those particle sizes, because those are the biggest things we're worried about is events, right. Heart attack, stroke and death. Those are the cardiovascular events that we're trying to prevent. All right. Biggest question of the night. When do we start getting lipid panels and how often should you get them?
Jason Liu, MD: [00:20:20] Um, so my my personal advice is lipid panels should be done at childhood. Um, the reason is you want to immediately capture those patients who have familial hypercholesterolemia. And so these are patients that may have mutations in their family history. And and some, you know, receptors that don't work very well, LDL receptors. And they have ldls in the two hundreds to four hundreds. Um, and what we've learned is that those kids that are treated for these ldls can live relatively normal lives. And so it's important to identify that lipoprotein little a right. You know again you know, there's a build up of the levels of lipoprotein is largely stable. Once you I believe it's like the age of ten or so. Right. And so having that checked as well. Yeah. Because that's going to impact how we manage the other risk factors.
Matthew DeVane, DO FAAC: [00:21:10] Well, I think in an ideal world, yes, the pediatricians would be checking all those things. But for most of the patients that we're seeing this stumbling about office at 30 or 40 or if we're lucky, or 50, I mean, I would I tell people is, listen, start getting your kids screened. Certainly as a young adult in your 20s, you should know your cholesterol numbers. It repeat them doesn't have to be every year if they're perfectly normal, but they should be watched at least every 3 to 5 years as a young person. And also the lipoprotein, a as you mentioned, should be done at least once in your lifetime. So if you haven't done it yet, get it done. And then if you work closely with your doctor and if your numbers are weird, come see one of us.
Jason Liu, MD: [00:21:47] So this this is, this is kind of interesting because we talk about, you know, getting things addressed when you're young. And so, um, what's the benefit of all this? And so there's always this question of can we reduce plaque burden. And so, you know, in the evaporate trial where they looked at Vascepa, there's probably some reduction in plaque volume looking assessed by coronary CT angiogram. Now in a in a study by mendieta et al. Basically where they looked at, you know, risk factor modifications that correlate potentially with plaque reduction based on CT coronary angiogram. What they found to correlate with the likelihood of plaque regression is age, LDL lowering and hypertension, management of hypertension and that young age, I believe in that in that age group is 44. So it adds all the more value to to screening for lipids, you know, in your 30s and 40s.
Matthew DeVane, DO FAAC: [00:22:43] Yeah, I think the earlier we can get to these things, the better you're going to be long term. Thus events, the better quality of life, less doctor visits. Treatment really works.
Carolyn Lacey, MD FACC: [00:22:54] Doctor Lou, thank you so much for being with us today. And it was a great review on our traditional lipid panel and some of our more modern measurements that we have, and get tested early and start your process to live a longer, healthier life. And in that thought, you know, I asked, our partners have been on the show already. The proverbial apple a day keeps the doctor away. And if there was one thing that you can think of that if you did almost every day, what would that be? To help live a longer and healthier life for you?
Jason Liu, MD: [00:23:29] Okay, so the best thing about being a cardiologist is that I can be really critical about everyone's diets and saturated fats. We haven't really talked about that. But you know, VLDL being a transport, right? The more saturated fats you eat, the more VLDL you need to transport that stuff. And so I tell people, you know, you just got to avoid the saturated fats, right? Butter, cheese, ice cream, cookies.
Carolyn Lacey, MD FACC: [00:23:53] You're taking away all our good stuff.
Jason Liu, MD: [00:23:55] Everything that brings you joy. You got to question it. But the best thing I could say, um, look at the label. You got a Marie Kondo. This thing I, um, I don't think many of you know, I don't know if all of you know Marie Kondo, but she's this, uh, Japanese spark. Joy. She declutters. Right. And so she declutter. She does the art of decluttering, and so she she looks at these little knickknacks that you have at home. And if it doesn't bring you joy, you throw it away, right? Declutter. And so when you look at that, when you look at that nutrition label and you see something that's high in saturated fat, you ask yourself, does this bring me joy? And can I live without it? And if you can get rid of it, oh my God.
Carolyn Lacey, MD FACC: [00:24:31] Nice.
Matthew DeVane, DO FAAC: [00:24:32] I love it. That's a great apple a day. No saturated fat.
Carolyn Lacey, MD FACC: [00:24:36] Perfect saturated fat.
Matthew DeVane, DO FAAC: [00:24:40] This is Doctor Matt DeVane, and on behalf of my co-host, Doctor Carolyn Lacey and our partners at John Muir Health, we hope that you enjoyed this show. And we really hope that you keep living heart smart.
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