Treatment of Chronic Post-stroke Oropharyngeal Dysphagia With Paired Stimulation

According WHO, oropharyngeal dysphagia (OD) is a prevalent post-stroke (PS) condition involving the digestive system (ICD-10: I69.391) and an independent risk factor for malnutrition and pulmonary infection; and leads to greater morbimortality and healthcare costs and poorer quality of life (QoL). Currently, OD therapy is mainly compensatory, with low rates of compliance and small benefit, and there is no pharmacological treatment, so new treatments that improve patients\' condition are crucial. PS-OD patients present both oropharyngeal sensory and motor deficits, so neurorehabilitation treatments which target both could be optimum. Benefits of paired peripheral sensory stimulation with oral capsaicin and of central motor noninvasive brain stimulation techniques such as transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS) will be studied. Pairing pharmacological peripheral and central stimulation may produce greater benefits. The main aim of the project is to study the efficacy of two novel protocols of paired stimulation on PS-OD patients. The investigators will assess whether 5-day application of tDCS/capsaicin or rTMS/capsaicin in the chronic phase of stroke, will improve PS-OD. One RCT (200 patients in the chronic stroke phase divided in 4 study arms) will assess changes in swallow safety, biomechanics and neurophysiology of the swallow response, hospital stay, respiratory and nutritional complications, mortality and QoL.