Journal Article

Pathogenesis of obstructive sleep apnea in individuals with the COPD + OSA Overlap syndrome versus OSA alone

Sun, Xiaoying S., Orr, Jeremy E., DeYoung, Pamela N., Owens, Robert L., Malhotra, Atul, Edwards, Bradley A., Brena, Rebbecca, Schmickl, Christopher N., Jain, Sonia

2020

Overview

Overlap syndrome (OVS) is the concurrence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA), and is associated with poor outcomes. We hypothesized that physiological changes in COPD may affect the pathogenesis of OSA in important ways. We therefore sought to measure the anatomical and nonanatomical OSA traits in individuals with OVS and compare to those with OSA alone. Patients with established OVS were recruited, along with age, gender, and BMI matched OSA only controls. Smoking and relevant comorbidities or medications were excluded. Subjects underwent baseline polysomnography followed by an overnight physiological research study to measure the OSA traits (Veupnea, Varousal, Vpassive, Vactive, and loop gain). Fifteen subjects with OVS and 15 matched controls with OSA alone were studied (overall 66 ± 8 years, 20% women, BMI 31 ± 4 kg/m2, apnea‐hypopnea index 49 ± 36/hr). Mixed‐modeling was used to incorporate each measurement (range 52–270 measures/trait), and account for age, gender, and BMI. There were no significant differences in the traits between OVS and OSA subjects, although OVS subjects potentially tolerated a lower ventilation before arousal (i.e., harder to wake; p = .06). Worsened lung function was significantly associated with worsened upper airway response and more unstable breathing (p < .05 for all). Consistent differences in key OSA traits were not observed between OVS and OSA alone. However, worse lung function does appear to exert an influence on several OSA traits. These findings indicate that a diagnosis of OVS should not generally influence the approach to OSA, but that lung function might be considered if utilizing OSA trait‐specific treatment. This is the first study to comprehensively measure both anatomical and non‐anatomical OSA traits during sleep in those with COPD + OSA (Overlap syndrome) and compare them to those with OSA alone. No consistent differences were found between the two groups, while worsened lung function did impact upper airway function and control of breathing. These findings have implications towards mechanisms underlying OSA, as well as management of sleep apnea.

• Publisher: John Wiley & Sons, Inc,John Wiley and Sons Inc,Wiley
• Subject: Aged / Apnea / Arousal / Cardiovascular disease / Chronic obstructive pulmonary disease / COPD / Female / Humans / Lung / Lung diseases / Male / Middle Aged / Obstructive lung disease / Original Research / OSA / Pathogenesis / Physiology / Pulmonary Disease, Chronic Obstructive - complications / Pulmonary Disease, Chronic Obstructive - physiopathology / Respiration / Respiratory Conditions Disorder and Diseases / Respiratory function / Sleep / Sleep apnea / Sleep Apnea, Obstructive - complications / Sleep Apnea, Obstructive - physiopathology / Sleep disorders