You are sitting in the sleep medicine clinic. It’s late afternoon and the hum of the HVAC is the only thing keeping you awake. Your next patient is Arthur, a 68-year-old male with a history of severe ischemic cardiomyopathy.

He shuffles in, looking pale and exhausted, accompanied by his wife, Martha, who looks equally drained. In fact, if you didn't have the schedule in front of you, you might have assumed they were both the patient; they are both wearing mismatched, unironed clothes and look profoundly deprived of sleep.