Risk of obstructive sleep apnea among patients with Cushing's syndrome: a nationwide longitudinal study

Objective: Previous studies have demonstrated the association between Cushing's syndrome (CS), obstructive sleep apnea (OSA),and the risk factors for OSA, but rarely provided the evidence within a large population. Using the Taiwan National Health Insurance Research Database, we attempted to investigate the association between CS and OSA, and to provide persuading evidences. Methods: In our study, 1612 patients with CS and 1612 age-, sex-, and comorbidities-matched controls were included, and followed up to the end of 2011. Cases of OSA were identified during the follow-up. Results: Among patients with CS, 53 developed OSA (incidence: 4.11 per thousand person-year) compared with 22 in the control group (incidence: 1.70 per thousand person-year) during the follow-up (p < 0.001). CS patients had a 2.82-fold higher risk of developing OSA (HR = 2.82; 95% CI: 1.67-4.77) in later life. Discussion: Our study was the first longitudinal study to support the temporal association between CS and risk of OSA. Patients with CS were associated with an increased likelihood of OSA. Further studies would be required to investigate the exact underlying mechanisms between CS and OSA, and elucidate whether the prompt intervention for CS may reduce the risk of subsequent OSA. (C) 2017 Elsevier B.V. All rights reserved.