Novel by Upper Airway Respiratory Muscle Training to Treat OSA in Chronic SCI

It is estimated that spinal cord injury (SCI) affects approximately 12,000 new individuals every year in the United States, with the majority are cervical and/or upper thoracic injuries. Despite this high prevalence of obstructive sleep apnea (OSA) in chronic SCI population minority of patients are treated and are adherent to standard therapy (CPAP). This proposal addresses a new therapeutic intervention for OSA in SCI. The investigators hypothesized that combined oropharyngeal and respiratory muscle exercises improve respiratory symptoms and alleviate OSA in patients with chronic SCI. The investigators will perform a pilot randomized, sham-controlled study to examine the impact of combined daily exercises (\~30 min) for 1 and 3 months durations among Veterans with SCI. The investigators believe that this novel approach to treating OSA and will yield significant new knowledge that improves the health and quality of life of these patients.

In recent years, the investigators and others have discovered that spinal cord injury/disease (SCI/D) is associated with significant increase in the sleep-disordered breathing (SDB) prevalence. Nearly 80% of patients with SCI/D including Veterans suffer from SDB after six months of injury (majority of them 70-80% are obstructive apneas and hypopneas-OSA). However, most patients SCI/D do not tolerate standard SDB treatment (continuous positive airway pressure-CPAP) leading to lack of compliance. Therefore, identifying other therapies is important for this common condition that is linked to poor outcome in the general population (heart disease, stroke, hypertension and poor cognition). It has been reported in sleep apnea able-bodied patients that oropharyngeal muscle exercises for 3 months using speech pathology techniques improve the severity of SDB. Furthermore, previous studies showed respiratory muscle training (RMT) is effective for increasing respiratory muscle strength in people with cervical SCI. However, the effect of combined oropharyngeal and RMT on OSA in patients with SCI is unknown.

The purpose of this application is to identify new therapeutic interventions for OSA treatment in Veterans with SCI/D. This application proposes for a pilot study to randomizing 30 Veterans with SCI/D and OSA to receive 3 months of daily (30 minutes) treatment with a validated set of oropharyngeal and RMT (intervention arm) versus sham therapy (control arm). There will be three specific aims to address the following hypotheses:

Specific Aim (1): To test recruitment rate and feasibility of a pilot intervention that includes combined oropharyngeal and RMT versus sham treatment in individuals with SCI/D.

Specific Aim (2): To test the acceptability and usability of combined oropharyngeal and RMT in individuals with SCI/D.

Specific Aim (3): To determine the effect size estimates for clinical endpoints and their associated variability at the end of treatment to calculate an appropriate sample size for an adequately powered clinical trial.

Eligibility Criteria:
Inclusion Criteria:

* Adult patients with chronic SCI/D (\>6 months post-injury)
* American Spinal Injury Association (ASIA) classification A-D who have evidence of OSA

  * excluding those with no evidence of a neurologic deficit based on ASIA classification
* Specifically, the study will target those with SCI/D and OSA who would like alternative treatment options or to have a lower PAP pressure, if they refused, or did not tolerate PAP treatment

Exclusion Criteria:

* Receiving continuous mechanical ventilation

  * except PAP therapy which is considered usual treatment for SDB)
* Severe congestive heart failure with ejection fraction \<35%
* Recent health event that may affect sleep

  * stroke
  * acute myocardial infarction
  * recent surgery
  * hospitalization
* Alcohol or substance abuse (\<90 days sobriety)
* Self-described as too ill to engage in study procedures
* Unable to provide self-consent for participation
* Central sleep apnea (CSA) defined as central apnea/hypopnea index \>50% of the AHI