RT Book, Section A1 Kasper, Dennis L. A1 Fauci, Anthony S. A1 Hauser, Stephen L. A1 Longo, Dan L. A1 Jameson, J. Larry A1 Loscalzo, Joseph SR Print(0) ID 1128786568 T1 Sleep Apnea T2 Harrison's Manual of Medicine, 19e YR 2016 FD 2016 PB McGraw-Hill Education PP New York, NY SN 9780071828529 LK accessmedicine.mhmedical.com/content.aspx?aid=1128786568 RD 2024/10/06 AB Sleep apnea is defined by the presence of at least five episodes per hour of apnea (no airflow for ≥10 seconds) and/or hypopnea (reduction in airflow by at least 30% from baseline for ≥10 seconds accompanied by oxygen desaturation or arousal from sleep). Obstructive sleep apnea/hypopnea syndrome (OSAHS) is caused by upper airway closure during inspiration, punctuated by brief arousals that terminate apneic episodes. Risk factors for OSAHS include obesity, craniofacial factors such as micrognathia, family history of OSAHS, and male sex. Hypothyroidism and acromegaly are systemic diseases associated with OSAHS. OSAHS increases the risk of multiple cardiovascular conditions, including coronary artery disease, heart failure, stroke, and arrhythmias.