Impact of Compliance on Dysphagia Rehabilitation in Head and Neck Cancer Patients: Results from a Multi-center Clinical Trial.

A 5-year, 16-site, randomized controlled trial enrolled 170 HNC survivors into active (estim + swallow exercise) or control (sham estim + swallowing exercise) arms. Primary analyses showed that estim did not enhance swallowing exercises. This secondary analysis determined if/how patient compliance impacted outcomes. A home program, performed 2 times/day, 6 days/week, for 12 weeks included stretches and 60 swallows paired with real or sham estim. Regular clinic visits ensured proper exercise execution, and detailed therapy checklists tracked patient compliance which was defined by mean number of sessions performed per week (0-12 times) over the 12-week intervention period. "Compliant" was defined as performing 10-12 sessions/week. Outcomes were changes in PAS, HNCI, PSS, OPSE, and hyoid excursion. ANCOVA analyses determined if outcomes differed between real/sham and compliant/noncompliant groups after 12 weeks of therapy. Of the 170 patients enrolled, 153 patients had compliance data. The mean number of sessions performed was 8.57/week (median = 10.25). Fifty-four percent of patients (n = 83) were considered "compliant." After 12 weeks of therapy, compliant patients in the sham estim group realized significantly better PAS scores than compliant patients in the active estim group (p = 0.0074). When pooling all patients together, there were no significant differences in outcomes between compliant and non-compliant patients. The addition of estim to swallowing exercises resulted in worse swallowing outcomes than exercises alone, which was more pronounced in compliant patients. Since neither compliant nor non-compliant patients benefitted from swallowing exercises, the proper dose and/or efficacy of swallowing exercises must also be questioned in this patient population.