Effect of expiratory muscle strength training on cough and swallowing in patients with dysphagia following stroke

Background: Previous research has shown that expiratory muscle strength training (EMT) increases voluntary cough strength and improves swallowing function in patients with Parkinson9s disease. However, these effects of EMT in dysphagia and aspiration pneumonia after stroke are still unclear. The purpose of this study was to identify whether EMT provide effects on cough strength and swallowing function in stroke patients with dysphagia. Methods: Twenty-one stroke patients with dysphagia were recruited. We used threshold loading device for EMT, with load of 75% of their maximum expiratory pressure (PEmax). The patients performed EMT 5 days per week for 4 weeks. We measured respiratory muscle strength, pulmonary function, cough peak flow, swallowing (repetitive saliva swallowing test; RSST) and phonatory function (maximum phonation time; MPT) before and after EMT program. Results: Sixteen patients completed EMT program. The significant improvement were shown in respiratory muscle strength (PEmax 50.3cmH 2 O vs 71.5cmH 2 O, p 2 O vs 39.1cmH 2 O, p 1 1.74L vs 1.92L, p Conclusion: EMT had improved on not only the coughing function but also swallowing function for a stroke patient with dysphagia. These results suggest that EMT leads to improvement of airway clearance and reduction of aspiration risk, and may be expected as a means to prevent aspiration pneumonia.