A recently awarded NIH funded Phase II Clinical Trial (2020-2025) will assess the potential for breathing to lower blood pressure in adults with Obstructive Sleep Apnea.

Bailey Lab

Exercise has well-documented benefits for systolic blood pressure (SBP) and cardiovascular health. Whereas current guidelines advocate ~150 min moderate intensity exercise/week, our preliminary data show ~5 min/day of inspiratory muscle strength training (IMST) for 6 weeks lowers casual (resting) SBP by ~12 mmHg. This simple approach to lowering BP could be applied to almost any population however we propose to study IMST in older adults with obstructive sleep apnea (OSA). OSA is an ideal population to target because OSA prevalence is growing and because snoring and apneas result in chronic intermittent hypoxemia that drives sympathetic nervous system (SNS) hyperactivity, endothelial dysfunction and hypertension. These substantive risks for cardiovascular disease are compounded by poor adherence to the mainstay treatment continuous positive airway pressure (<50%), obesity, fatigue and a robust intolerance for exercise. Our findings in healthy young adults (n=50) show IMST-related reductions in BP are mediated by decreases in systemic vascular resistance, suggesting changes in vascular tone and function. Consistent with this hypothesis, our results from a pilot clinical trial in adults with OSA (n=24) show IMST-related reductions in plasma norepinephrine levels (PNE) and muscle sympathetic nerve activity (MSNA), both markers of SNS activity. We propose a randomized, double-blind, placebo-controlled, clinical trial to establish the efficacy of at home IMST (75% maximum inspiratory pressure, [PImax]) 5 days/week for 24 weeks vs. placebo (15%PImax) (n=61/group) for lowering SBP in adults (>50 years) with above normal BP and OSA. We hypothesize that IMST will lower SBP via reductions in SNS activity and circulating vasoconstrictor factors, improvements in vascular function, and reductions in oxidative stress/inflammation and that reductions in SBP will be sustained after IMST.

 

People: 
 

E. Fiona Bailey, PhD

Professor, BIO5 Institute
Professor, Evelyn F Mcknight Brain Institute
Professor, Physiology
Professor, Speech/Language and Hearing
(520) 626-8299
ebailey@email.arizona.edu
Research Gate


Claire M. DeLucia, M.S.

deluciac@email.arizona.edu

Sarah Schwyhart, B.S.

sarahschwyhart@email.arizona.edu

 

Research: 

Exercise has well-documented benefits for systolic blood pressure (SBP) and cardiovascular health. Whereas current guidelines advocate ~150 min moderate intensity exercise/week, our preliminary data show ~5 min/day of inspiratory muscle strength training (IMST) for 6 weeks lowers casual (resting) SBP by ~12 mmHg. This simple approach to lowering BP could be applied to almost any population however we propose to study IMST in older adults with obstructive sleep apnea (OSA). OSA is an ideal population to target because OSA prevalence is growing and because snoring and apneas result in chronic intermittent hypoxemia that drives sympathetic nervous system (SNS) hyperactivity, endothelial dysfunction and hypertension. These substantive risks for cardiovascular disease are compounded by poor adherence to the mainstay treatment continuous positive airway pressure (<50%), obesity, fatigue and a robust intolerance for exercise. Our findings in healthy young adults (n=50) show IMST-related reductions in BP are mediated by decreases in systemic vascular resistance, suggesting changes in vascular tone and function. Consistent with this hypothesis, our results from a pilot clinical trial in adults with OSA (n=24) show IMST-related reductions in plasma norepinephrine levels (PNE) and muscle sympathetic nerve activity (MSNA), both markers of SNS activity. We propose a randomized, double-blind, placebo-controlled, clinical trial to establish the efficacy of at home IMST (75% maximum inspiratory pressure, [PImax]) 5 days/week for 24 weeks vs. placebo (15%PImax) (n=61/group) for lowering SBP in adults (>50 years) with above normal BP and OSA. We hypothesize that IMST will lower SBP via reductions in SNS activity and circulating vasoconstrictor factors, improvements in vascular function, and reductions in oxidative stress/inflammation and that reductions in SBP will be sustained after IMST.

Lab News: 
  • Ramos-Barrera GE, DeLucia CM & Bailey EF. (2020). Inspiratory muscle strength training lowers blood pressure and sympathetic activity in older adults with OSA: A randomized controlled pilot trial. J Appl Physiol (1985)

  • Reply to Dr. Beltrami E. Fiona Bailey Journal of Applied Physiology 2020 129:6, 1440-1440

  • Delucia CM, Debonis D, Schwyhart S, & Bailey EF (2021). Acute cardiovascular responses to a single bout of high intensity inspiratory muscle strength training in healthy young adults. J Appl Physiol (in revision)