Table 1.
Required Symptoms, Findings, and/or Comorbidities for Central Disorders of Hypersomnolence, According to the ICSD-3
| NT1 | NT2 | IH | |
|---|---|---|---|
| Daily periods of irrepressible sleep need or daytime lapses into sleep | |||
| X | X | X | |
| Objective measures: Laboratory | |||
| - Hypocretin (orexin) deficiency | (X) | – | – |
| Objective measures: PSG or actigraphy | |||
| - ≥11 h sleep per 24 h | (P) | (X) | |
| - Sleep efficiency ≥90% | (S) | ||
| Objective measures: MSLT | |||
| - Low mean sleep latency (≤8 min) | (X) | X | (X) |
| - <2 SOREMs (including PSG) | X | ||
| - ≥2 SOREMs (including PSG) | (X) | X | |
| Reported measures: Symptoms | |||
| - Cataplexy | (X) | – | – |
| - Sleep inertia, unrefreshing naps | (P) | (S) | |
| Reported measures: Sleep–wake behavior | |||
| - Sleep time shorter than expected | – | – | |
| - Sleep time curtailed by an alarm clock, etc. | (P) | ||
| - Longer sleep during weekend/vacation | (P) | ||
| - Sleepiness remits with longer sleep | – | – |
NC1 and NC2 = narcolepsy type 1 and 2; IH = idiopathic hypersomnia; X = mandatory criterion; (X) = either/or criterion, or facultative criterion; (S) = supportive criterion; – = must be absent for the diagnosis; (P) = not considered a classic feature but sometimes present.