Reversible Effect of Falling Ventilatory Drive in Drive-dependent OSA
Brigham and Women's Hospital
Summary
Obstructive sleep apnea (OSA) is a highly prevalent disorder that has major consequences for cardiovascular health, neurocognitive function, risk of traffic accidents, daytime sleepiness, and quality of life. For years, a "classic" model of OSA has been used to describe the disorder, which fails to capture it's complexity. Recently, a model for OSA called drive-dependent OSA was discovered be more prevalent in the OSA population. The drive-dependent subgroup benefits exclusively from increased ventilation, increased dilator muscle activity, and reduced event risk when drive spontaneously rises. This study seeks to provide direct evidence that reducing the loss of drive prevents the loss of ventilation, pharyngeal muscle activity, and thus the onset of OSA respiratory events, specifically in "drive-dependent" but not "classic" OSA. This will be achieved using CO2 delivered at precise times during breaths in sleep to prevent loss of overall ventilatory drive.
Description
This is a detailed physiological study, with gold-standard measurements of ventilatory drive and dilator muscle activity, we aim to mitigate falling drive with carefully-timed inspired CO2 administration in patients with (N=18) and without (N=18) drive-dependent OSA. We will test the hypothesis that OSA events are preventable by mitigating falling drive exclusively in drive-dependent OSA. Subjects will attend a virtual Screening and Consent visit to assess eligibility for enrollment. Participants will take part in a video call with the consenting doctor to obtain consent (Zoom). After consent…
Eligibility
- Age range
- 21–80 years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * Diagnosed OSA (AHI≥15 events/h reported in a PSG performed within 1 year) or Suspected OSA (snoring, sleepiness, witnessed apneas, other clinical symptoms) * Use of CPAP or other therapies is acceptable; individuals will be asked to withhold treatment for 3 days before each study visit. Individuals who are occupational drivers or operate heavy machinery will not be asked to withhold treatment. Exclusion Criteria: * Any unstable medical conditions * Conditions that could meaningfully raise the cardiovascular risks of brief low-dose hypercapnic-hypoxic inspired gas mixtu…
Interventions
- OtherDynamic CO2
2% inspired CO2 for 2-4 breaths
- OtherSham CO2
Air
Location
- Brigham and Women's HospitalBoston, Massachusetts