The use of handheld nasal spirometry to predict the presence of obstructive sleep apnea

Nasal obstruction and oral breathing may play an important role in the pathophysiology of obstructive sleep apnea (OSA). This study aims to better understand the link between oral breathing, nasal obstruction, and the spectrum of sleep-disordered breathing.

Prospective study.

Prospective study of patients who presented to the Otolaryngology clinic and underwent polysomnogram (PSG) from 2015 to 2016. Patients were divided into two groups based on the severity of their OSA as defined by PSG results. Both apnea-hypopnea index (AHI) and supine and REM AHI (SUP-REMe AHI), a parameter that takes into account both sleep position and sleep stage, were recorded. The primary outcome was awake nasal-oral forced expiratory volume in 1-s (FEV1) ratio as measured by handheld spirometry.

A total of 21 patients were included in the study. We found that nasal-oral FEV1 ratio was significantly different between patients with minimal and substantial OSA as stratified by SUP-REMe AHI, while not significant when stratified by AHI.

Patients with substantial OSA as determined by SUP-REMe AHI are more likely to have decreased awake nasal airflow as measured by nasal-oral FEV1. SUP-REMe AHI may represent an improved metric of OSA severity by taking into account sleep position and sleep stage. Handheld spirometers have the potential to become an important office tool by allowing for easy and reliable measurement of nasal airflow.