Snapshot A 56-year-old man presents to your office for excessive fatigue. He complains of falling asleep all the time at work, which is “very distressing" as it has been affecting his work. He denies sudden loss of muscle tone or hallucinations before or after falling asleep. His wife reports that he snores at night. A physical examination demonstrates an obese, lethargic man with unremarkable findings. Introduction Presentation Studies Diagnostic testing diagnostic approach diagnosis is based on clinical history and physical exam (especially if significant risk factors are present) and confirmed via an in-laboratory polysomnography studies home sleep apnea testing acceptable alternative for patients strongly suspected of OSA without medical comorbidities in-laboratory polysomnography gold standard diagnostic test for sleep apnea differentiates OSA from CSA Diagnostic criteria OSA 15 obstructive apneas/hour 5 apneas/hour and snoring/breathing pauses with daytime somnolence Differential Narcolepsy distinguishing factor clinical features such as cataplexy, hypnagogic hallucinations, sleep attacks, and sleep paralysis can be differentiated on polysomnography Respiratory disease (e.g., chronic obstructive lung disease) distinguishing factor positive medical history and polysomnography results Treatment Complications daytime fatigue (increased risk for motor vehicle accidents) hypertension and other cardiovascular conditions pulmonary hypertension may result in cor pulmonale type 2 diabetes and other metabolic conditions arrhythmias