Cystic fibrosis itself, longer life expectancy are possible factors, research suggests

Host Amber Smith: Upstate Medical University in Syracuse New York invites you to be "The Informed Patient" with the podcast that features experts from Central New York's only academic medical center. I'm your host, Amber Smith.

Just three decades ago, the average person with cystic fibrosis would live only to the age of 30, but now 50 years is typical, and some patients with CF live into their 80s. This means they live long enough for other health concerns to surface. Here to tell us about that is Dr. Andres Cordova Sanchez. He's a resident physician in internal medicine at Upstate, and he presented research on this subject this fall at the annual meeting of the American College of Chest Physicians.

Welcome to "The Informed Patient," Dr. Cordova.

Andres Cordova Sanchez, MD: Hello Amber. How are you doing?

Host Amber Smith: I'm well, thanks. I'd like to have you explain how it is that the life expectancy has improved so much for patients with cystic fibrosis.

Andres Cordova Sanchez, MD: There are several factors that that play a role here. I think that it took us several decades to really understand how the disease works and get some working drugs for it. So there are some milestones that have happened across the decades. One of them was the discovery of the CFTR gene and therapies that can actually work in this specific protein. What happens with patients with cystic fibrosis is that a protein that is involved in the production of mucus in the body gets altered.

And as a result you have a lot of very thick and sticky mucus, especially in the lungs and in other organs like the pancreas. By using specific enzymes and specific medications that target this protein, we can really dramatically improve the life of these patients.

And to that, we have other therapies that have been discovered, like the use of antibiotics, early recognition of the disease with neonatal screening in the U.S. and respiratory therapy.

Host Amber Smith: So basically new treatments have evolved and have made a significant impact, it sounds like?

Andres Cordova Sanchez, MD: Yes, exactly.

Host Amber Smith: Now, how is it that some patients live even into their 80s? That seems amazing to me.

Andres Cordova Sanchez, MD: It is certainly amazing, and I do have to say that's not the most common thing, at least in the pool of patients that I used for my research. For example, we only had about 10 patients that lived in their 80s. And I think it really depends on how the disease presents in these patients and how they respond to the medication. It's really more of an individual response rather than the norm.

Host Amber Smith: Now, you did a study looking at patient medical records that you presented at the American College of Chest Physicians Conference, is that right?

Andres Cordova Sanchez, MD: Yes. We took a large database of patients across the world and looked into the electronic medical records to pull out data. This type of research, it allows us to have a big picture of what's going on and have a good approximation of what is happening in real life, but it also has the caveat that we can't really, for example, go into each patient's chart and identify specific problems.

Host Amber Smith: Why is it significant that one in 10 adults with cystic fibrosis were found to have a diagnosis of heart failure?

Andres Cordova Sanchez, MD: Well, one in 10 adults means that it's a very common disease in these patients. And what's even more interesting is that once you divide the patients by age the patients start to have older ages. They have much more rates of heart failure. So, as we see that we have every decade patients with cystic fibrosis live longer, this is going to become much more prevalent issue in the future. And we should start thinking about how to attack it, how to help these patients.

Host Amber Smith: How prevalent were heart attacks, or myocardial infarction, in adults with cystic fibrosis?

Andres Cordova Sanchez, MD: We found approximately 4% of patients having myocardial infarctions. This is about what the general population has.

I know atrial fibrillation is an issue. Did you see that in people with cystic fibrosis as well?

Andres Cordova Sanchez, MD: Yes. Atrial fibrillation was actually a very interesting finding. Overall, we found a rate of 4%, but once you take all those patients that live more than 50 years, that were more than 50 years old, the incidence, the rate of atrial fibrillation went up significantly.

Those patients had 15% or more, and every decade as the patients grew older, let's say patients that were 60 years old, they had 20%. And patients that were 70 years old, they had 25% of atrial fibrillation. So it is very common in these patients.

Host Amber Smith: This is Upstate's "The Informed Patient" podcast. I'm your host, Amber Smith. I'm talking with Dr. Andres Cordova Sanchez. He's a resident physician in internal medicine at Upstate, and he's done research on cystic fibrosis and heart disease.

Now, we think of cystic fibrosis as a lung disease, mostly, but how does cystic fibrosis affect the cardiovascular system just in general?

Andres Cordova Sanchez, MD: So there are two ways in which we think cystic fibrosis can affect the heart. One of them is indirectly, which is the most obvious way. So, by affecting the lungs you have pulmonary hypertension, which is basically high blood pressure in the vessels of the lungs, and that makes it harder for the heart to pump blood into the lungs, which can cause right heart failure.

You also have low oxygen levels, and that will cause, also, issues with the heart. And because these patients have a lot of inflammation going on, this chronic inflammation can cause a lot of issues as well. So that's indirectly. And directly, we are not completely sure so far, but there are some studies that have identified this protein that's altered, in cystic fibrosis, in their heart.

So some studies suggest that this might be related with arrhythmias, but we are not completely sure what its function is.

Host Amber Smith: Is heart disease in cystic fibrosis patients more of a risk for men or women, or did you notice a difference?

Andres Cordova Sanchez, MD: I did not notice much of a difference. In reality, the differences were very small when we compared both. it seemed that males had more arrhythmias and heart failure, but I cannot really make a conclusion based on the data that I have.

Host Amber Smith: Is heart disease treated the same way in someone with CF as it is in someone who doesn't have CF?

Andres Cordova Sanchez, MD: So far, yes. And that's where it can get tricky as well, because the treatment of heart failure depends on the type of heart failure. And although we don't know exactly what type of heart failure is more common in these patients, I imagine it's going to be right-sided heart failure just because of what we were talking about -- pulmonary hypertension. This type of heart failure is difficult to treat. We don't really have great medications for it. So it's definitely an area in which we have to look more into.

Host Amber Smith: Now, I think patients with heart failure in general are recommended a low-salt diet. Is that right?

Andres Cordova Sanchez, MD: Yes.

Host Amber Smith: So, well, I wonder, will that work for someone with cystic fibrosis?

Andres Cordova Sanchez, MD: That's actually a very interesting topic. I don't think it will work. Patients with cystic fibrosis are usually recommended a high-calorie diet with high salt, which is kind of the contrary of what we recommend for heart failure. So it will really need to be an individually recommended diet for each patient based on what their weight is and so on and so forth.

Host Amber Smith: Thinking of heart failure, but also some of the other heart diseases, do you think that they have an impact on the life expectancy for someone who has cystic fibrosis?

Andres Cordova Sanchez, MD: I don't know for certain if they impact, but I would imagine it does. Certainly heart failure is a disease that in the general population carries a high burden. It's very symptomatic and it can be very difficult to leap with and also has a, can have a high rate of mortality. So I expect that in these patients, the life expectancy will be also affected.

Host Amber Smith: Work like yours, it seems to me, would let people with cystic fibrosis know that this is something to be aware of. Are they able to do more than that with the information? Are there preventive steps they can take or screenings that they can sign up for?

Andres Cordova Sanchez, MD: I don't think they should worry too much about this at this stage because we are really starting to characterize heart disease in these patients. But having regular follow-ups with their physicians is vital. I am sure any physician will be able to recognize heart failure in these patients and set them up with cardiology and whatever other resources that they need.

Host Amber Smith: Well, Dr. Cordova, I really appreciate you making time to share your research with us. Thank you.

Andres Cordova Sanchez, MD: Thank you very much.

Host Amber Smith: My guest has been Dr. Andres Cordova Sanchez. He's a resident physician in internal medicine at Upstate. "The Informed Patient" is a podcast covering health, science and medicine, brought to you by Upstate Medical University in Syracuse, New York, and produced by Jim Howe. Find our archive of previous episodes at Upstate.edu/informed. This is your host, Amber Smith, thanking you for listening.