Arousal perception/misperception and total sleep time misperception in subjects with sleep disorders

Limited studies have examined arousal perception in obstructive sleep apnea (OSA) or other sleep disorders. The aim of this study is to evaluate the factors that affect patients’ arousal and total sleep time perception. This is a retrospective study of 210 subjects divided into 5 groups: Primary insomnia; upper airway resistance syndrome (UARS)/primary snoring; mild, moderate and severe OSA. Perceived arousals were compared to objectively defined arousals. The subjects’ age, body mass index (BMI), total sleep time (TST), perceived TST, sleep efficiency, stage shifts, rapid eye movement (REM) and delta time were compared. UARS/primary snoring group had significantly higher perceived arousal relative to arousal events and shorter total arousal duration than in primary insomnia and all OSA groups. There was a significant linear increase in total arousals and respiratory arousal as OSA severity increased. The number of perceived arousal events was negatively correlated with perception of TST. There was a trend for the insomnia group to have more perceived non-respiratory arousals compared with all OSA groups. Although subjects with UARS/primary snoring had the lowest total arousals, they perceived the highest arousals. The non-respiratory related arousals are probably perceived differently from respiratory arousal related perception. For the insomnia group to have more arousals not driven by respiratory events suggests that insomnia may be better defined as a disorder by being driven to arousals rather than apneas, who are aroused despite being driven towards sleep.