The role of peak nasal and oral inspiratory flow in the evaluation of patients with sleep-related breathing disorders

Abstract

Background: Sleep-related breathing disorders (SRBD) are common reported disorders in the adult population. The nose plays an important role in the development of SRBD; thus, the measurement of nasal respiratory function remains an important step in the management of these patients. Peak nasal inspiratory flow (PNIF) is a useful tool to assess nasal airflow and it has recently been studied together with peak oral inspiratory flow (POIF). Objective: The aim of the present study was to evaluate the role of PNIF and POIF in an adult population of patients affected by SRBD. Methodology: Seventy consecutive adult patients with SRBD were included in the present study. All patients were evaluated with home-based sleep studies (type III), PNIF, POIF, SNOT-22 questionnaire, Epworth Sleepiness Scale test and VAS for nasal obstruction. Results: Although PNIF and POIF showed to correlate with each other, no correlations were observed between Apnea Hypopnea index (AHI) and PNIF, POIF or NPI (PNIF/POIF). A further analysis showed a marginal correlation between SNOT- 22 and AHI and between SNOT-22 and POIF. Furthermore, in a multivariate analysis, also POIF marginally correlated with some of the sleep- related SNOT-22 items. Conclusions: In the present study neither PNIF nor POIF were found to be associated with OSAS severity. However, POIF values correlated better than PNIF with sleep related symptoms suggesting that POIF could be a more useful parameter for upper airway assessment in patients with SRBD. In addition, a correlation between OSAS severity, in terms of AHI, and SNOT-22 total score has been reported.