Cough peak flow as a predictor of pulmonary morbidity in patients with dysphagia

The aim of this study was to ascertain whether an objective cough measure relates to the risk of pulmonary complications in dysphagic patients with persistent tracheobronchial aspiration.

This is a retrospective observational study involving 55 dysphagic patients who underwent a modified barium swallow study and pulmonary function tests including cough peak flow measurement. The results were compared between subjects with and without pulmonary complications because of aspiration.

The 18 patients (33%) with pulmonary complications had significantly lower mean cough peak flow values (202.2 ± 68.8 vs. 303.9 ± 80.7 liters/min; P < 0.001) than those without pulmonary complications. The finding of tracheobronchial coating in a modified barium swallow was not related to the occurrence of pulmonary morbidity. Receiver operating characteristic curve analysis showed that a CPF level lower than 242 liters/min predicted the development of pulmonary complications with a sensitivity of 77% and a specificity of 83%; the positive and negative predictive values were 65% and 90%, respectively.

Our findings indicate that cough peak flow is a valuable predictor of respiratory prognosis in chronic aspiration. This finding suggests a new rehabilitation strategy aimed at improving cough flows for dysphagic patients.