Asthma predicts 8-year incidence of obstructive sleep apnea in the Wisconsin sleep cohort

Introduction Cross-sectionally, obstructive sleep apnea (OSA) is more common among asthmatics, but whether asthma promotes development of OSA in adulthood remains unknown. We investigated whether the presence or development of asthma is associated with risk of new-onset OSA in Wisconsin Sleep Cohort Study (WSCS) participants. Materials and methods At four-year intervals, WSCS participants (ages 30–60 years in 1988) completed in-laboratory polysomnography, clinical assessments, and health history questionnaires. We used logistic regression to model the association of presence of asthma and odds of incident 8-year OSA (apnea–hypopnea index (AHI) ⩾ 5 or OSA treatment initiation) among participants free of OSA (apnea–hypopnea index  Results Of 1545 WSCS participants with baseline studies, 773 had no OSA at baseline and an 8-year follow-up study. Of these 773 participants, 201 had asthma (61 childhood-onset, 140 adult-onset). Relative to those without asthma, those with asthma at any age had 1.70 times (95% CI = 1.15–2.51) greater odds of new-onset OSA. Each increment in asthma duration of 5 years was associated with 10% higher odds (1.01–1.19) of new-onset OSA at 8-year follow-up. Relative to no asthma, childhood-onset asthma was associated with 2.34 times (1.25–4.37) and adult-onset asthma with 1.48 times (0.92–2.36) greater odds of new-onset OSA. There were 45 subjects who developed asthma during follow-up. New-onset asthma was unassociated with new-onset OSA, both in the model that included asthma with onset at any age (which remained significantly associated 1.67 times (1.12–2.50) and when stratified by age of onset (childhood- onset 2.28 [1.24–4.20] and adult-onset asthma 1.44 [0.88–2.35]). Conclusion In adults, presence of asthma, particularly childhood-onset asthma, predicted 8-year risk of developing OSA. Incremental asthma duration by 5 years was associated with 10% higher odds for OSA 8 years later. Whether and how intrinsic disease characteristics or associated features starting early in life affect upper airway patency during sleep remains unknown. Acknowledgements This work was supported by the National Heart, Lung, and Blood Institute (R01HL62252) and the National Center for Research Resources (1UL1RR025011) at the National Institutes of Health.