Could Calcium Supplements be Hurting Your Heart?

Podcast Transcript

Announcer:

Welcome to Love Your Heart, brought to you by Cleveland Clinic's Sydell and Arnold Miller Family Heart, Vascular & Thoracic Institute. These podcasts will help you learn more about your heart, thoracic and vascular systems, ways to stay healthy and information about diseases and treatment options. Enjoy.

Samir Kapadia, MD:

I'm Samir Kapadia, Chairman of Cardiology at Cleveland Clinic, and it's my great pleasure to have with me today, Dr. Kassis, Nick Kassis. He is a third year medical resident who is going to be a Cardiology fellow soon. So it is my great pleasure to discuss this very interesting research that we did together on patients with aortic stenosis.

Samir Kapadia, MD:

What is the aortic stenosis is that the main valve of the heart, which is the aortic valve, sometimes gets narrowed. So in about 5% of the people at 75 years of age, the calcium gets into the valve leaflets and that makes the valve somewhat narrow. It does not open fully. What we tried to study was if the calcium supplements make this worse or not, and this is what was the study, and maybe Dr. Kassis can explain to us that what exactly how you're dating the study.

Nicholas Kassis, MD:

Sure. So thank you Dr. Kapadia for the intro. So basically what we looked at is in 2,600 patients that we studied retrospectively, so looking backwards from 2008 to 2016, we followed these patients to 2018, looking at those who took calcium supplementation, those who took vitamin D supplementation and those who didn't take any supplementation. What we found is that those who took calcium supplementation specifically were at a much higher risk of mortality, almost double the rate than those who did not take any supplementation, as well as increased risk for needing a valve replacement. So this sort of raised some eyebrows given the high rate. So what we gleaned from this study is that our main message is that those who are taking calcium supplementation, it's important to talk to your physician, someone who knows you and your needs best about whether you need it, whether it's indicated and whether the risk and benefits outweigh each other.

Samir Kapadia, MD:

That's wonderful summary. So one part was that when we started the study, we of course were trying to figure out that way that the calcium supplements, because this calcium in the bloodstream is the... Was it surprising that there was such a big difference that we found in the study?

Nicholas Kassis, MD:

Yeah, so I would say that the big difference certainly was something we weren't expecting. Knowing some of the literature that already exists, we did expect some difference and the mechanism behind why there would be a difference is still up for debate. But certainly, whether or not calcium causes these or is identifying these patients who are high risk at baseline anyways, is a question that we're still investigating. But certainly, we know that those who have been taking calcium supplements during this time were at high risk.

Samir Kapadia, MD:

So for my perspective, two things that are important. One is that we did find that people require more aortic valve replacement. Second was that people did have higher mortality when they were taking calcium supplementation. The third was that the aortic valve calcification per se or the stenosis getting worse, we could not identify that very clearly in our database.

Nicholas Kassis, MD:

Right, that's correct.

Samir Kapadia, MD:

However, if you look at the literature together, the complete literature, it appears that calcium supplementation meaning taking larger doses of calcium may not be really necessary because we want to have the calcium going to the bone for osteoporosis. This is the most common reason why people take it is because they want to prevent the bone from getting depleted from the calcium. Vitamin D3 may be more helpful and that may be the link that you can take vitamin D3 and that may help you for osteoporosis. You don't have to take extra calcium because if you're taking 1,200 milligrams per day, that may be enough calcium.

Nicholas Kassis, MD:

Right. I think that's a very excellent point specifically about the dosage of the calcium. This is something that we didn't study per se in this study and I think that's some future directions of next study should be looking at certain doses in which one is safe and if there's a threshold. Then secondly is about the mode of getting your calcium. All the studies that exist now do support the use of dietary calcium and not supplemental calcium because the dietary calcium has not been associated with these worse outcomes. So if you can get it from the diet, we would definitely recommend to sort of prioritize that.

Samir Kapadia, MD:

So you don't want to decrease the dietary calcium. So this is not what the message is. This is a supplemental calcium. The second is that vitamin D3 in itself was not associated, at least in our study, associated with bad outcomes. So this is also very important message for people to know that you are safe to take vitamin D3.

Samir Kapadia, MD:

So what would we recommend to the people who are taking vitamin D is to reach out to their physicians, try to understand what is the dietary intake of calcium. If it reaches the guided therapy and guided dietary requirement, which is 1,200 milligrams per day, then you don't need to take extra calcium. If you are below that limit and if your doctors feel that you need additional calcium, then maybe change the diet such that you have additional dietary calcium, or if necessary take the calcium supplements under proper supervision. That would be the right message.

Samir Kapadia, MD:

There is not easy way to measure the calcium levels in the bloodstream to guide these therapies. So this is another important thing to keep in mind that it is not something that you can measure. Vitamin D3 level you can measure, but not so much the calcium level that can be, because it's the overall source.

Nicholas Kassis, MD:

Exactly, and particular foods. If you're wondering particular foods that have, that are rich in calcium include things like dairy, so yogurt and low fat milk, almonds and leafy greens. So those are some things to be aware of.

Samir Kapadia, MD:

That is wonderful, and thank you again for being here with us and it's outstanding study, a great job for that.

Nicholas Kassis, MD:

I appreciate it. Thank you.

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