Peak Voluntary Cough Flow and Oropharyngeal Dysphagia as Risk Factors for Pneumonia.

Objective: To investigate the relationship between voluntary peak cough flow (PCF), oropharyngeal dysphagia, and pneumonia in patients who were evaluated with videofluoroscopic swallowing study (VFSS).

Methods: Patients who underwent both VFSS and PCF measurement on the same day were enrolled retrospectively (n=821). Pneumonia (n=138) and control (n=683) groups were assigned based on presence of pneumonia within 1 month from the date of VFSS assessment. In addition, sex, age (<65 and ≥65 years), preceding conditions, modified Barthel Index (MBI), Mini-Mental State Examination (MMSE), PCF value (<160, ≥160 and <270, and ≥270 L/min), and presence of aspiration/penetration on VFSS were reviewed.

Results: Pneumonia group was more likely to be male (n=108; 78.3%), ≥65 years (n=121; 87.7%), with neurodegenerative (n=25; 18.1%) or other miscellaneous diseases (n=50; 36.2%), and in poor functional level with lower value of MBI (39.1±26.59). However, MMSE was not significantly different in comparison to that of the control group. The pneumonia group was also more likely to have dysphagia (82.6%) and lower value of PCF (<160 L/min, 70.3%). In multivariable logistic regression analysis, male sex (odd ratio [OR]=6.62; 95% confidence interval [CI], 2.70-16.26), other miscellaneous diseases as preceding conditions (OR=2.52; 95% CI, 1.14-5.58), dysphagia (OR=3.82; 95% CI, 1.42-10.23), and PCF <160 L/min (OR=14.34; 95% CI, 1.84-111.60) were factors significantly related with pneumonia.

Conclusion: Impaired swallowing and coughing function showed an independent association with the development of pneumonia. Patients with PCF <160 L/min require more attention with lung care and should be encouraged with voluntary coughing strategy to prevent possible pulmonary complications.