Types, Assessment, and Treatment of Apnea
Sleep-disordered breathing includes OSA, central sleep apnea (CSA), periodic breathing (including Cheyne-Stokes breathing), and sleep-related hypoventilation. OSA affects approximately 24% of men and 9% of women between 30 and 60 years of age. Several studies revealed that the prevalence of OSA is substantially higher among patients with AF (ranging from 32% to 39%), indicating that OSA could be contributing to the initiation and progression of AF.
OSA is caused by repeated upper airway collapse leading to oxygen desaturation and disrupted sleep. Pathogenesis varies; predisposing factors include small upper airway lumen, unstable respiratory control, low arousal threshold, and dysfunctional upper airway dilator muscles. Risk factors include obesity, male sex, age, menopause, fluid retention, adenotonsillar hypertrophy, and smoking. Continuous positive airway pressure (CPAP) is the treatment of choice for OSA, with adherence of 60%–70%. The positive pressure keeps the pharyngeal area from collapsing, and thus helps alleviate the airway obstruction.
Bi-level positive airway pressure or adaptive servoventilation can be used for patients who are intolerant of CPAP. Other treatments include mandibular advancement devices, upper airway surgery, and lifestyle modification (weight loss, avoidance of alcohol and sedatives).