The frequency of chronic rhinosinusitis/nasal polyp in COPD and its effect on the severity of COPD.

This study aimed to investigate the effect of chronic rhinosinusitis/nasal polyposis on the severity of COPD and to find out whether the 'united airway disease' hypothesis is valid for COPD. The study enrolled 90 patients diagnosed and staged according to criteria of an international guideline for diagnosis and management of COPD. The patients in stages I and II were classified as Group 1 and the patients in stages III and IV as Group 2.