Figure 1. Relationship between ORP in total sleep time and during the first 9 seconds after arousal and wake time.
(A) Relationship between average odds ratio product (ORP) in total sleep time and wake time in all patients (n = 267). Normals = normal sleepers in the Sleep Heart Health Study, NWT-NP = in hospital studies with normal wake time (NWT) and no associated pathology, NWT+P = in hospital studies with NWT and obstructive sleep apnea (OSA) and/or periodic limb movements (PLMs), EWT-NP = patients with excessive wake time (EWT; sleep efficiency < 80%) and no associated pathology, EWT+P = EWT and associated OSA/PLMs. (B) Same relation but using ORP during the first 9 seconds after arousal instead of ORP during sleep.