Obstructive sleep apnoea accelerates FEV1decline in asthmatic patients.
Although the prevalence of both obstructive sleep apnoea (OSA) and asthma are both increasing, little is known about the impact of OSA on the natural history of lung function in asthmatic patients.



A total of 466 patients from our sleep laboratory were retrospectively enrolled. Of them, 77 patients (16.5%) had asthma with regular follow-up for more than 5 years. Their clinical characteristics, pulmonary function, emergency room visits, and results of polysomnography results were analysed.



The patients were divided into three groups according to the severity of the apnoea-hypopnea index (AHI). The decline in FEV1among asthma patients with severe OSA (AHI > 30/h) was 72.4 ± 61.7 ml/year (N = 34), as compared to 41.9 ± 45.3 ml/year (N = 33, P = 0.020) in those with mild to moderate OSA (5 < AHI ≤ 30) and 24.3 ± 27.5 ml/year (N = 10, P = 0.016) in those without OSA (AHI ≤ 5). For those patients with severe OSA, the decline of FEV1significantly decreased after continuous positive airway pressure (CPAP) treatment. After multivariate stepwise linear regression analysis, only AHI was remained independent factor for the decline of FEV1decline.



Asthmatic patients with OSA had substantially greater declines in FEV1than those without OSA. Moreover, CPAP treatment alleviated the decline of FEV1in asthma patients with severe OSA.
Pulmonary Disease Research Centre, Department of Thoracic Medicine, Chang Gung Memorial Hospital, Chang Gung University, School of Medicine, 199 Tun-Hwa N. Rd., Taipei, Taiwan.
Tsai-Yu
TY
Wang
Pulmonary Disease Research Centre, Department of Thoracic Medicine, Chang Gung Memorial Hospital, Chang Gung University, School of Medicine, 199 Tun-Hwa N. Rd., Taipei, Taiwan.
Yu-Lun
YL
Lo
Pulmonary Disease Research Centre, Department of Thoracic Medicine, Chang Gung Memorial Hospital, Chang Gung University, School of Medicine, 199 Tun-Hwa N. Rd., Taipei, Taiwan.
Shu-Min
SM
Lin
Pulmonary Disease Research Centre, Department of Thoracic Medicine, Chang Gung Memorial Hospital, Chang Gung University, School of Medicine, 199 Tun-Hwa N. Rd., Taipei, Taiwan.
Chien-Da
CD
Huang
Pulmonary Disease Research Centre, Department of Thoracic Medicine, Chang Gung Memorial Hospital, Chang Gung University, School of Medicine, 199 Tun-Hwa N. Rd., Taipei, Taiwan.|Department of Thoracic Medicine, St. Paul's Hospital, Taoyuan, Taiwan.
Fu-Tasi
FT
Chung
Pulmonary Disease Research Centre, Department of Thoracic Medicine, Chang Gung Memorial Hospital, Chang Gung University, School of Medicine, 199 Tun-Hwa N. Rd., Taipei, Taiwan.
Horng-Chyuan
HC
Lin
Pulmonary Disease Research Centre, Department of Thoracic Medicine, Chang Gung Memorial Hospital, Chang Gung University, School of Medicine, 199 Tun-Hwa N. Rd., Taipei, Taiwan.
Chun-Hua
CH
Wang
Pulmonary Disease Research Centre, Department of Thoracic Medicine, Chang Gung Memorial Hospital, Chang Gung University, School of Medicine, 199 Tun-Hwa N. Rd., Taipei, Taiwan. q8828@ms11.hinet.net.
Han-Pin
HP
Kuo
D000328:Adult; D000368:Aged; D001249:Asthma / Q000150:complications*; D045422:Continuous Positive Airway Pressure; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017286:Polysomnography; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology* / Q000628:therapy*; D013624:Taiwan
Obstructive sleep apnoea; Pulmonary function; asthma