Preserved ratio impaired spirometry and severity of obstructive sleep apnea: An observational cross-sectional study

Lung function abnormality of obstructive sleep apnea (OSA) has not been explored well. Preserved ratio impaired spirometry (PRISm) is known for its association with obesity and cardiovascular morbidity, which are also characteristic features of OSA. This study aims to investigate whether the prevalence of PRISm increases according to apnea-hypopnea index levels among subjects with OSA.