| Category | Examples |
| Pulmonary diseases | Severe chronic obstructive pulmonary disease Chronic hypercapnic or hypoxemic respiratory failure |
| Cardiac diseases | Congestive heart failure |
| Neuromuscular diseases and hypoventilation syndromes | Central sleep apnea, obesity hypoventilation syndrome, neuromuscular diseases |
| Effects of drugs including substance use/abuse | Opioids, gabapentinoids, other respiratory depressants |
| Other conditions | Prior upper airway surgery |
