How obesity affects nasal function in obstructive sleep apnea: anatomic and volumetric parameters.

INTRODUCTION: Obstructive sleep apnea is a consequence of upper airway collapse. Any obstructive sector in the upper airway can contribute to pharyngeal collapse. Obesity and obesity-related disorders play an important role in obstructive sleep apnea and its relationship with increased upper airway resistance. OBJECTIVE: This study was designed to evaluate the relationship between obesity and properties of the nasal cavity in patients with obstructive sleep apnea. METHODS: The study was conducted retrospectively by review of medical records of adult patients. The nasal obstruction symptom evaluation, NOSE instrument, was used to measure nasal obstruction. Sleep breathing disorders were evaluated by polysomnography exams. Nasal volume was obtained by computed tomography scans and volumetric reconstruction of nasal airway. Nasal anatomic alterations were assessed by nasal endoscopy. RESULTS: Analysis of 83 patient records, among whom 54 were male and 29 females, found the mean body mass index of 28.69 kg/m2. Obese and non-obese groups were determined by using cut-off 30 kg/m2. In the comparison between groups, the obese group had a positive and significant correlation with apnea/hypopnea index (p = 0.02), NOSE instrument (p = 0.033) and inferior turbinate hypertrophy (p = 0.036), with odds ratio 1.983 (95% IC 1.048 - 3.753). nasal septum deviation (p = 0.126) and nasal airway volume evaluation (p = 0.177) showed no significant results. CONCLUSION: Obesity was significantly correlated with subjective nasal obstruction, NOSE scale, and inferior turbinate hypertrophy in patients with obstructive sleep apnea. There was no correlation with the nasal volume evaluation. LEVEL OF EVIDENCE: 3b - Individual case-control study.