Short-Term Stability of Sleep and Heart Rate Variability in Good Sleepers and Patients with Insomnia: For Some Measures, One Night is Enough

Abstract

Most QEEG bandwidths and HRV during sleep show high short-term stability in good sleepers and patients with insomnia alike. One night of data is, thus, sufficient to derive reliable estimates of these outcomes in studies focused on group differences or correlates of QEEG and/or HRV. In contrast, one night of data is unlikely to generate reliable estimates of PSG-assessed sleep duration, continuity or architecture, with the exception of slow wave sleep.

Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society on the Recommended Amount of Sleep for a Healthy Adult: Methodology and Discussion

“…117 Retrospective self-report, the most common method in epidemiologic studies and in clinical practice, is easy and has good face validity. However, sleep duration can vary substantially over time, [118][119][120] and there is little information on how individuals account for such variation in their reports. Also, self-report questions may have captured time in bed rather than time asleep.…”

Sleep in Healthy Black and White Adolescents

“…Selfreport measures of sleep are often examined with regard to a long interval of time (eg, last 3 months) or their "typical" pattern; however, some dimensions of sleep can vary markedly from night to night. 16 Time diaries of activities and sleep throughout 24 hours require compliant, conscientious participants. The dynamic and changing nature of adolescence, coupled with marked changes in sleep and circadian rhythms during adolescence, suggests that a multimethod approach to assessing sleep is necessary to obtain a comprehensive picture of adolescents' sleep.…”

The Accuracy, Night-to-Night Variability, and Stability of Frontopolar Sleep Electroencephalography Biomarkers

“…In the patients, the autonomic activation index (AAI), a measurement of brief but important episodic changes in pulse rate, was found to be 2 times greater during NREM sleep as compared to REM sleep, a difference similar to the NREM and REM ratio of low-to high-frequency heart rate variability (HRV). 41,42 The night-to-night variability of the AAI and HRV were also similar during both NREM sleep (0.82 versus 0.90) and REM sleep (0.80 versus 0.89). 41 These findings suggest that both low HRV and low AAI are measuring increased sympathetic dominance, 43 a finding supported by the lower REM AAI in patients taking antihypertensive medications.…”

“…41,42 The night-to-night variability of the AAI and HRV were also similar during both NREM sleep (0.82 versus 0.90) and REM sleep (0.80 versus 0.89). 41 These findings suggest that both low HRV and low AAI are measuring increased sympathetic dominance, 43 a finding supported by the lower REM AAI in patients taking antihypertensive medications. Each autonomic activation event requires a 10-second detection window, thus tallying and computing an index for REM and NREM is possible in patients with limited REM time or who suffer from highly fragmented sleep.…”