According to the lung function of patients with OSAHS, the correlation between OSAHS and peripheral airway resistance was explored.

This was a cross-sectional study conducted in respiratory department of affiliated hospital of Qinghai university from August 2017 to August 2019. Adult patients who lived in Qinghai Province, were diagnosed with OSAHS were enrolled. According to apne-hypopnea index (AHI), patients were divided into three groups: mild group (5≤AHI≤15), moderate group (15<AHI≤30), and severe group (AHI>30). Spearman correlation analysis was used to explore the correlation between AHI and R5-R20. The multivariable linear regression models were used to study the relationship between severity of OSAHS and R5-R20. In addition, subgroup analyses were conducted based on sex and chronic obstructive pulmonary disease (COPD) to further explore the relationship between severity of OSAHS and R5-R20.

A total of 184 adult patients diagnosed with OSAHS were included in this study. Spearman correlation analysis showed that the R5-R20 increased with the elevation of AHI (r=0.402, P<0.001). Multivariable linear regression analysis showed that every degree of OSAHS severity increased, R5-R20 increased (β, 0.340, 95%CI, 0.199-0.481, P<0.001). After that, the results of subgroup analysis showed that the relationship between OSAHS severity and R5-R20 still exists in females and males (females: β, 0.517; 95%CI, 0.207-0.827, P=0.002; Male: β, 0.309; 95%CI, 0.144-0.474, P<0.001), or in non-COPD group and COPD group (non-COPD: β, 0.262, 95%CI, 0.113-0.410, P=0.001; COPD: β, 0.497, 95%CI, 0.154-0.840, P=0.005).

Severity of OSAHS is related to peripheral airway resistance. Patients in higher degree of OSAHS severity had higher peripheral airway resistance and the risk of the prevalence of chronic bronchitis.