A close relationship between upper and lower respiratory tract diseases has been reported. However, little is known about pulmonary function in patients with upper respiratory tract diseases.

Pulmonary function was measured in: 68 patients with chronic rhinosinusitis without nasal polyps, 135 patients with chronic rhinosinusitis with nasal polyps, 89 patients with allergic rhinitis and 100 normal control subjects. The relationships between pulmonary function and clinical parameters were assessed. These parameters included radiographic severity of chronic rhinosinusitis, serum total immunoglobulin E levels, concentrations of cytokines in nasal secretions and exhaled nitric oxide levels.

The pulmonary function of patients with chronic rhinosinusitis was significantly affected. The level of interleukin-5 in nasal secretions was significantly correlated with pulmonary function in patients with chronic rhinosinusitis.

The findings indicated latent obstructive lung function changes in chronic rhinosinusitis patients. The cytokines in nasal secretions might be related to obstructive lung function changes in chronic rhinosinusitis.