UArizona Physiology Clinical Trial to Study a Simple Breathing Exercise for Obstructive Sleep Apnea

Wednesday, August 4, 2021

TUCSON, Ariz. — Researchers at the University of Arizona College of Medicine – Tucson, a part of UArizona Health Sciences, are launching a Phase II clinical trial to assess the long-term effectiveness of a unique respiratory training protocol known as “inspiratory muscle training” for reducing blood pressure and improving cardiovascular health in adults with obstructive sleep apnea.

E. Fiona Bailey, PhD, a professor in the Department of Physiology at the UArizona College of Medicine – Tucson, was awarded a five-year, $3.4 million grant from the National Institute on Aging, a division of the National Institutes of Health, to build on her group’s previous research that showed a respiratory workout entailing 30 breaths a day can lower blood pressure.

“High blood pressure is a major risk factor for cardiovascular disease, which is the number one cause of death in America. Five minutes a day of inspiratory muscle training, consisting of just 30 inspiratory efforts against resistance, offers a low-cost, non-pharmacologic means of improving both sleep quality and blood pressure,” said Dr. Bailey, who specializes in respiratory physiology.

Obstructive sleep apnea is a serious health condition in which the muscles of the throat relax during sleep and collapse inward so that air cannot reach the lungs for a short period. This causes oxygen deprivation and repeated awakening from sleep. Together, nightly oxygen deprivation and the inability to achieve uninterrupted sleep contribute to an increased risk of developing high blood pressure and cardiovascular disease. Prior research has shown obstructive sleep apnea affects about 50% of adults in the U.S. and nearly 1 billion people worldwide.

The new clinical trial will provide an opportunity for Dr. Bailey and her research team, which includes collaborators at the University of Colorado at Boulder, to implement inspiratory muscle training over six months in a larger group of 50-to-80-year-old adults with obstructive sleep apnea and above-normal blood pressure. The team will follow up with participants three months after the training ends to see how long the blood pressure-lowering effects last. 

Study participants will undergo initial screenings of cardiovascular, respiratory and sleep health. Eligible participants will be randomly assigned to one of two training groups, one emphasizing high resistance training the other emphasizing low resistance training. Participants in both groups will perform their training at home and complete 30 breaths per day, 5 days a week, for 24 weeks.

Inspiratory muscle training originally was devised for use by athletes and people with breathing problems, such as chronic obstructive pulmonary disease, asthma and bronchitis. Dr. Bailey has adapted the protocol for everyday use by adults with obstructive sleep apnea. In its current format, inspiratory muscle training can be performed at home, at work or when travelling, using a hand-held training device similar to an inhaler. 

Results of early studies by Dr. Bailey’s group showed inspiratory muscle training builds respiratory muscle strength and has a surprising secondary benefit – it lowers blood pressure. The reduction in blood pressure is greater than that gained from traditional aerobic exercise and in many instances, can exceed reductions achieved with blood pressure medications. The results of this early work are published in the journals Sleep and Journal of Applied Physiology

Continuous positive airway pressure, or CPAP, is the standard therapy for obstructive sleep apnea and is effective at reducing oxygen deprivation during sleep, but many users discover they are unable to tolerate it throughout the night.

Regular aerobic exercise can help and is important for cardiovascular health, but current recommendations are for 150 minutes per week of moderate intensity exercise. This amount of exercise can be a difficult to achieve – fewer than 30% of American adults meet this minimum – and may be especially challenging for adults with obstructive sleep apnea, many of whom experience chronic fatigue and excess daytime sleepiness. 

“New cost-effective and time-efficient strategies are needed to manage the health issues caused by obstructive sleep apnea,” said Dr. Bailey, also a member of the BIO5 Institute. “It is vitally important that we devise new approaches to help people keep their blood pressure under control and improve cardiovascular health.” 

Dr. Bailey’s prior findings recently were confirmed by collaborators Drs. Douglas Seals and Daniel Craighead at the University of Colorado Boulder Department of Integrative Physiology. In that study, they demonstrated that six weeks of inspiratory muscle strength training by older adults with above-normal blood pressure reduced blood pressure and improved arterial health, contributing to an overall reduction in the risk of developing cardiovascular disease.
 
For more information on participating in the clinical trial, contact Lupita Ramos-Barrera at 520-626-0836 or baileylaboratory@email.arizona.edu, or visit https://redcap.link/breathe.

Research discussed in this publication is supported by the National Institute of Aging, a unit of the National Institutes of Health (R01AG065346-01A1). This project is approved by the University of Arizona Institutional Review Board.

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Photos available: https://arizona.box.com/s/inl7qeljj7ph9e2vnwzpf1d4ju9vu1cl

Reporters and editors: Please note that the University of Arizona Health Sciences is separately recognized from the University of Arizona, similar to other academic health centers across the country. The preferred first reference is University of Arizona Health Sciences; the preferred second reference is UArizona Health Sciences. 
 

Media contact:
Jo Marie Barkley
520-626-7219
jgellerm@arizona.edu

About the University of Arizona College of Medicine – Tucson
The University of Arizona College of Medicine – Tucson is shaping the future of medicine through state-of-the-art medical education programs, groundbreaking research and advancements in patient care in Arizona and beyond. Founded in 1967, the college boasts more than 50 years of innovation, ranking among the top medical schools in the nation for research and primary care. Through the university's partnership with Banner Health, one of the largest nonprofit health-care systems in the country, the college is leading the way in academic medicine. For more information: medicine.arizona.edu (Follow us: Facebook | Twitter | LinkedIn | Instagram).

About the University of Arizona Health Sciences
Located on campuses in Tucson and Phoenix, the University of Arizona Health Sciences is one of the top-ranked academic medical centers in the southwestern United States. UArizona Health Sciences includes the College of Medicine – Phoenix, College of Medicine – Tucson, College of Nursing, College of Pharmacy and the Mel and Enid Zuckerman College of Public Health. In addition, 12 UArizona Health Sciences centers focus on cancer, neurodegenerative diseases, pain and addiction, and respiratory diseases; biomedical informatics, health technology innovation and simulation training; and precision health care and health disparities. A leader in next-generation education, biomedical research and public outreach, UArizona Health Sciences employs nearly 5,000 people, has approximately 4,000 students and 900 faculty members, and garners more than $200 million in research grants and contracts annually. For more information:  uahs.arizona.edu (Follow us: Facebook | Twitter | YouTube | LinkedIn | Instagram).