Effect of Transcutaneous Electrical Stimulation in Chronic Poststroke Patients with Oropharyngeal Dysphagia: 1-Year Results of a Randomized Controlled Trial

Background. Chronic poststroke oropharyngeal dysphagia (CPSOD) is associated with impaired oropharyngeal sensory/motor function. We aimed to assess effect of sensory (SES) and motor (NMES) transcutaneous electrical stimulation (TES) on safety of swallow and clinical outcomes in patients with CPSOD in a one-year follow-up randomized controlled trial. Methods. Ninety patients (74.1 +/- 11.5 y, modified Rankin score 2.6 +/- 1.7) with CPSOD and impaired safety of swallow were randomized to (a) compensatory treatment (CT), (b) CT + SES, and (c) CT + NMES. Patients were treated with up to two cycles (6 months apart) of 15 x 1 hour TES sessions over two weeks and followed up with 4-5 clinical and videofluoroscopic assessments during one year. Key results. Baseline penetration-aspiration scale (PAS) was 4.61 +/- 1.75, delayed time to laryngeal vestibule closure (LVC) 396.4 +/- 108.7 ms, and impaired efficacy signs 94.25%. Swallowing parameters significantly improved between baseline and 1-year follow-up in SES and NMES groups for prevalence of patients with a safe swallow (P < .001), mean PAS (P < .001), time to LVC (P < .01), and need for thickening agents (P < .001). Patients in the CT presented a less intense improvement of signs of impaired safety of swallow without significant changes in time to LVC. No differences between groups were observed for 1-year mortality (6.1%), respiratory infections (9.6%), nutritional and functional status, QoL, and hospital readmission rates (27.6%). No significant adverse events related to TES were observed. Conclusions and inferences. Transcutaneous electrical stimulation is a safe and effective therapy for older patients with CPSOD. After 1-year follow-up, TES greatly improved the safety of swallow and reduced the need for fluid thickening in these patients.