Amy Attaway: "You're listening to the ATS Breathe Easy podcast brought to you by the American Thoracic Society. Hello everyone. My name is Amy Attaway and I'm here hosting another episode of the ATS Breathe Easy podcast and I am so excited to be here with Dr. Irene Cano Pumarega. So Dr. Cano is going to be talking about the really exciting findings of her Pavlov randomized control trial which she'll be presenting on tomorrow at ATS. Dr. Cano is a professor of sleep medicine and the head of the sleep unit at the Hospital Universitario Ramón y Cajal in Madrid. Her work focuses on obstructive sleep apnea especially positional obstructive sleep apnea, hypoxemia, cardiovascular outcomes and translational sleep physiology. And I'll just give a brief summary of her trial, but it's basically looking at whether positional therapy can treat positional obstructive sleep apnea and whether you can produce a lasting conditioning response. So really exciting things and I thank you so much for being here, Dr. Cano. We'd love to hear more about the study".
Dr. Irene Cano: "Thank you for the invitation and I'm very glad to be here with you sharing my results".
Amy Attaway: "Oh, thank you. Thank you so much. So can you talk about kind of how the study was designed and I know you're kind of focusing on positional obstructive sleep apnea and treating it right, is that correct?"
Dr. Irene Cano: "Yeah. Yeah. That's correct. I mean the ability to sleep apnea is a very, very common disease and there are like between 50 and two-thirds of the patients have what we call positional sleep apnea. That means that this apnea is more frequent when they are on their backs. Okay. And for these type of patients the golden standard treatment that is the CPAP is not very well tolerated. So there's another alternative treatment. This positional therapy that is a vibrating device that vibrates when the patient is on their supine position on their back and it stimulates them to change the position. So we wanted to assess only not only if it was an effective treatment but also if it has a conditioning effect because in my clinic some patients told me, 'Oh, I think there are change and I think I can correct my sleep apnea without the treatment'. So that was the hypothesis why I called the study Pavlov Study. All right? Because I wanted to check if this conditioning effect exists and if we can correct the sleep apnea without an active treatment".
Amy Attaway: "Okay. No, that's fascinating. And can you tell me can you explain more how the device works? I know you said that it will kind of stimulate them or how does it work to get them to change position?"
Dr. Irene Cano: "Okay. It has a sensor and it's positioned on a belt, on a thoracic belt. Okay. And when the sensor gets that the patient is on the back on the supine position it makes a vibration with a different type of vibration and it is enough to change the position but not to wake up the patient totally up".
Amy Attaway: "And so you're saying that you would prescribe this therapy and then your patients were... and then it the study would end but the patients were telling you that they were still... they could still feel, you know, they were still in the right position. How did you get the idea for the study I guess?"
Dr. Irene Cano: "Our study had two phases. The first phase was a six-month phase and during this stage of the study half of the patients were on CPAP treatment and half of the patients were on the positional device. So at the end of this six months we performed another sleep study to check which patients were responders and we defined a responder patient when the apnea hypopnea index was below 15 events per hour and when it was a reduction of at least 50% of the apnea hypopnea index. So after this six months we decided to discontinue the treatment in both arms. I mean the CPAP patients were without CPAP and the positional therapy patients were without the treatment and we checked one week after discontinuation the treatment and one month after discontinuation the treatment if it was still effective without an active treatment. Right. Without the CPAP and without the positional therapy. Yeah. And here comes a spoiler because it was such good results that we continued the study 3 months after discontinuation the treatment and one year that is what I'm presenting in this actual ATS".
Amy Attaway: "Oh wow that's so exciting and you'll be presenting on that tomorrow. So I think I know we're all excited about it. So you're saying that the positional therapy group showed a sustained effect at one year?"
Dr. Irene Cano: "Yeah. No, in one week after the discontinuation and one month after discontinuation, 80% of the patients with the positional therapy treatment were still responders. And in the CPAP arm there was a... one week after discontinuation we have like 30% of responders, one month 40%, but here comes the big results: after 3 months 0% of the CPAP patients were responders. That's normal, that's what we expected, but 78% of the patients that were with the positional device treatment were still responders and after one year 72% of the patients were still responders. That's two-thirds of the patients. So that's really good because they were one year without any treatment and we included all types of sleep apnea: mild, moderate, or even severe patients".
Amy Attaway: "Oh wow. No that has I think a ton of implications right. I think when I trained, we were told to put positional therapy, how to treat it, was putting the tennis ball, right? Like sewing it in the clothes to try to get it to shift. This sounds like this device is a lot more sophisticated, but then if it has a lasting effect, then maybe it doesn't have to stay with one patient. Is that what you're..."
Dr. Irene Cano: "Yeah, that's what our thoughts and it was very well tolerated because what happened with the tennis ball... yeah, they were effective but in the long term nobody uses them because they were very uncomfortable. And the difference with this device that was very, very comfortable and the patients prefer the positional therapy even than the CPAP. We have during the six months that was the first stage of the study 30% of the patients under CPAP treatment discontinued the treatment because of intolerance and only 4% of the patients under the positional therapy treatment discontinued because of intolerance. So that were very good numbers".
Amy Attaway: "That's that's really exciting. So what do you think is the next step? Do you think are you thinking of doing another trial like a crossover trial or what are kind of your..."
Dr. Irene Cano: "Right now we are studying the same patients to know if there is what we call an extinction phenomenon. I mean maybe in the year two, that after the summer we are doing the first two years studies and maybe some patients they are not responders anymore. So we have to check for how long the patients are going to be responders. If is described this extinction phenomenon if they can, for example, use for another six month treatment and they can continue being responders without any treatment. And we are analyzing right now the difference and the characteristic of the responder patients to check from the beginning which one will respond to the therapy and who will not".
Amy Attaway: "Well, that's so exciting. Yeah. I because I treat mostly COPD patients and we definitely see a lot of responders, non-responders to therapy. So it's great when you have the responders, but you also want to know why the people did not respond".
Dr. Irene Cano: "And that's what we call the precision medicine. Yeah. We want to offer different therapies and to know in which one fits better".
Amy Attaway: "Mhm. And do you and I guess we didn't really talk much about why like why did this happen like because you said you were surprised that even you I mean you were very happy about the trial results but that the persistence of the effect even at a year. So and I know that's part of your research right like the conditioned response. So have you thought about why this worked so well or can you kind of you know speculate on that?"
Dr. Irene Cano: "I mean you learned how to avoid a position that was the hypothesis and yeah, but I didn't expect that it lasted so much time, so we don't know yet".
Amy Attaway: "Okay, all right. So and you do some translational work right translational research so maybe we can that's something you can look at in the future maybe the pathways the biology of it".
Dr. Irene Cano: "Yeah, right now I'm doing precision medicine work to study the endotypes and the phenotypes of all the patients that I have with different therapies to know from the beginning and even from the data that we have from the first sleep study if we can define the responders and the best choice for treatment for each patient".
Amy Attaway: "Yeah, that's exciting. So yeah, so I think we've been seeing more and more how important precision medicine is and how, you know, CPAP is a great tool, but it just it doesn't always work for everyone. So something a really exciting future. I know there's lots of new therapies in obstructive sleep apnea as well. So it's kind of a really exciting field".
Dr. Irene Cano: "That's it. Yeah. Yeah. Yeah. We have some pharmacology... so there..."
Amy Attaway: "Yeah. D1 treatment. Yeah. Always positional this I guess we're moving past the ping pong or sorry the tennis ball in the sewed into the shirt. So anyway, well that's wonderful. So I think we're all excited to see you present tomorrow and I think more to come. Hope you hope to see this published soon. So congratulations to you and your this great work and thank you for the interview".
"Thank you for joining us today. To learn more, visit our website at thoracic.org. Find more ATS Breathe Easy podcasts on Transistor, YouTube, Apple Podcasts, and Spotify. Don't forget to like, comment, and subscribe so you never miss a show".