Abstract
BACKGROUND: Hypoxic ventilatory response (HVR) is weakened in patients with obstructive sleep apnea-hypopnea syndrome (OSAS) compared to healthy people, however, the mechanisms remain unknown. Our previous study found a positive human leukocyte antigen (HLA)-DQB1*0602 status was related to lower HVR, which indicate gene background may play a critical role in HVR.
OBJECTIVES: To examine HVR in Chinese Han and Uygur OSAS patients and investigate whether ethnic differences contribute to HVR alterations.
METHODS: 215 subjects with suspected OSAS were recruited (n=70 for Han people, n=145 for Uygur people). All the patients underwent polysomnography (PSG), spirometry and oximetry tests. Apnea-hypopnea index(AHI), hypopnea index (HI),mean SaO2(MSaO2%), the lowest SaO2(LSaO2%), the time spent at SaO2 below 90%(SIT90%), the number of desaturations ≥ 4% per hour(ODI4)and hypoxic ventilatory response(ΔVE/ΔSaO2) changes were measured.
MEASUREMENTS AND MAIN RESULTS: Uygur patients had a higher apnoea/hypopnoea index (AHI) (36.4 ± 26.4/h vs 14.1 ± 8.2/h), more ODI4 (26.9 ± 3.0 /h vs 8.9 ± 1.2/h), longer SIT90 (19.7±3.1 vs 9.6±1.9), and lower LSaO2 (76.2±10.2% vs83.9±9.0%) than Han patients of the same age and body mass index (BMI).Compared to Han patients, Uygur patients had weaker hypoxic responsiveness (-0.40±0.22 L·min-1·%-1vs -0.32±0.18 L·min-1·%-1; p<0.05); the difference still exists after adjusting AHI (-0.25±0.19 L·min-1·%-1vs -0.46±0.15 L·min-1·%-1; p<0.05).
CONCLUSIONS: HVR is closely associated with ethnic background, but independent of age and BMI.
- Copyright ©the authors 2016