Training Swallowing Initiation during Expiration: Impact on Safety and Efficiency Following Treatment for Oropharyngeal Head and Neck Cancer

Oropharyngeal head and neck cancers (OP HNC) have increased to epidemic levels in the United States.1,2 Despite good response to cancer treatment, survivors are suffering life-long toxicities that result in swallowing problems (dysphagia).3,4 Treatment options for dysphagia after OP HNC are extremely limited and focus on swallowing movements alone, with no consideration of respiratory-swallow phase coordination.5-13 Prior evidence has demonstrated the importance of this coordination in patients with OP HNC.14,15 Specifically, when aberrant respiratory-swallow phase patterning is present (initiation of swallowing during inspiration), there is a higher occurrence of swallowing impairments, increased residue, and airway invasion.14,15 Further, it has been well established in the literature that the expiratory limb of the respiratory cycle (initiation of swallowing during expiration) provides a biomechanically advantageous set point in which to initiate safe and efficient swallowing.16-19 Thus, we developed and tested an innovative approach to train individuals with dysphagia after OP HNC to initate swallowing during expiration using visually guided feedback from the patient’s own respiratory movements.20 In this preliminary trial, we found that training initiating of swallowing during expiration lead to marked improvements in airway protection and key physiologic components of swallowing function.20 These compelling findings lead us to the current Phase II randomized, sham-controlled clinical trial to test if this respiratory-swallow phase training approach will improve airway protection and swallowing efficiency in OP HNC survivors in the subacute phase (3-6 mo) of recovery. Our primary goal is to (Aim 1) determine if respiratory-swallow phase training results in increased frequency (%) of swallows initiated during expiration and improved swallowing safety. Our secondary goal is to (Aim 2) examine the impact of respiratory-phase training on the frequency of swallows initiated during expiration in wakeful, naturalistic swallowing environments, including eating and drinking. To accomplish this, we will recruit 88 OP HNC survivors with impaired airway safety and respiratory-swallow phasing to be randomized 1:1 into Experimental (n=44) or Sham (n=44) group arms. We will deliver therapy remotely using a telehealth platform and an innovative wearable sensor that provides real-time feedback of respiratory and swallow movements. Primary endpoints for Aim 1 include 1) frequency (%) of swallows initiated during expiration and 2) Penetration-Aspiration Scale21 scores, with key secondary endpoints including Normalized Residue Ratio Scale22 and Modified Barium Swallow Impairment Profile23,24 measurements from synchronized videofluoroscopic and respiratory recordings at baseline and 1-week, 1-month, and 3-months post-treatment. The primary endpoint for Aim 2 is frequency (%) of swallows initiated during expiration in wakeful, natural contexts measured pre-treatment, during training, post-treatment, and 2-, 4-, 6-, 8-, 10-, and 12- weeks post-treatment. Consistent with the NCI’s mission, this study may discover a new therapy option, that could be combined with traditional