Previously collected data from our institution shows that rapid eye movement (REM)sleep time and slow wave sleep time do not affect perception of total sleep time (TST). No differences in sleep perception amongst diagnostic groups; obstructive sleep apnea (OSA), upper airway resistance syndrome (UARS), primary snoring and primary insomnia were observed. The aim of the current study is to evaluate if other factors contribute to TST perception.
One hudred and eighty (180) subjects were retrospectively divided into 3 groups: 1. normal estimators [within 1 standard deviation (SD)] 2. abnormal estimators [within 2 SDs] 3. severely abnormal estimators > 2SDs]. Standard deviation was relative to percent of estimated TST. Perception estimates were compared for each diagnostic group; primary insomnia, UARS/primary snoring and mild, moderate and severe OSA. The subjects’ perception of how much they slept was compared with objectively determined TST by NPSG. Factors evaluated were: age, body mass index(BMI), apnea/hypoapnea index(AHI), sleep efficiency (SE), sleep onset (SO), SOREM, number of REM periods, REM time, number of total arousals, respiratory and non-respiratory arousals and number of stage shifts. Diagnostic NPSG inclusion criteria were normal REM sleep time, TST minimum = 4.5 hrs. Many exclusion criteria used, two were absence of REM altering medications or benzodiazepines.
Data showed that 121 (67%) of all subjects estimated TST to within 1SD, 29% within 2SDs and 4% > 2SDs, for their respective diagnostic group. Two macro-sleep factors appeared to significantly influence perception: TST [group 2, 352.4 ± 30.1 < group 1 (324.5 ± 37.3) p < 0.001] and the number of stage shifts [group 3 (109.4 ± 10.5) < group 1 (154.6 ± 44.4) < group 2 (155.2 ± 54.4) p < 0.04]. No significant differences between groups were observed for any other sleep and demographic factors.
Thirty-three percent(33%) of subjects with various disorders abnormally perceive their sleep. Subjects with the greatest sleep misperception had the lowest number of stage shifts.
Greater sleep continuity results in sleep misperception possibly secondary to the absence of memory consolidation opportunities arousals would provide.
Zinobia Khan, No Financial Disclosure Information; No Product/Research Disclosure Information