Background: the upper and lower airway form one contagious functional unit and exposed to same similar inflammatory stimuli that support hypothesis disease in one part could reflect or manifest on another.
Objective: to assess the effects of sinonasal polyposis on ventilatory function test pre and post functional endoscopic sinus surgery (FESS).
Methodology: This interventional randomized controlled clinical trial was carried out on 30 patients presented with chronic rhinosinusitis with nasal polyposis. All patients were subjected to nasal obstruction scale evaluation (NOSE) assessment, nasal endoscopic examination, Lund MacKay CT score and PFT pre and three months post FESS.
Results: there was a significant decrease of 2 items of NOSE scale (nasal obstruction and trouble sleeping), endoscopic examination score, and Lund MacKay CT score, with significant increase of PFT (FEV₁ %, FVC %, FEV₁\FVC ratio and FEF25-75%) three months post-operatively compared to preoperative values (p-value < 0.001). In the preoperative period 73.3% had an obstructive pattern in PFT while in the post-operative period only 36.6% had an obstructive pattern in PFT (p =0.004). By using multivariate logistic regression analysis, the most significant predictive factors of abnormal PFT in patients with sinonasal polyposis were right CT Lund MacKay scale (B= 0.74, p =0.014), left CT Lund MacKay scale (B= 0.56, p = 0.01), and total Lund MacKay CT score (0.4, p= 0.01).
Conclusions: the sinonasal polyposis have negative effects in PFTs that improved after FESS. The predictive factor for reduced PFTs in patients with sinonasal polyposis is Lund MacKay CT score.