Format

Send to

Choose Destination
Sleep. 2015 Nov 1;38(11):1727-34. doi: 10.5665/sleep.5152.

Short- and Long-Term Sleep Stability in Insomniacs and Healthy Controls.

Author information

1
Sleep Research and Treatment Center, Department of Psychiatry, Pennsylvania State University College of Medicine, Hershey, PA.
2
Department of Psychiatry, School of Medicine, University of Crete, Heraklion, Crete, Greece.
3
Department of Public Health Sciences, Pennsylvania State University College of Medicine, Hershey, PA.

Abstract

STUDY OBJECTIVES:

Assess the short- and long-term stability of sleep duration in patients with insomnia and normal-sleeping controls.

DESIGN:

Observational short-term and prospective studies.

SETTING:

Sleep laboratory.

PARTICIPANTS:

Patients with insomnia (n = 150) and controls (n = 151) were recruited from the local community or sleep disorders clinic. A subsample of 95 men from the Penn State Adult Cohort (PSAC) were followed up 2.6 y after their initial visit.

MEASUREMENTS:

Participants underwent a physical examination and 8-h polysomnography (PSG) recording for 3 consecutive nights (controls and insomniacs), or 2 single nights separated by several years (PSAC). Intraclass correlation coefficients (ICCs) assessed the stability of the variables total sleep time (TST), sleep onset latency (SOL), and wake after sleep onset (WASO). We also examined persistence of the first-night classification of "short" versus "normal" sleep duration on subsequent nights.

RESULTS:

Stability of TST, SOL, and WASO based on 1 night were slight to moderate in both patients with insomnia (ICC = 0.37-0.57) and controls (ICC = 0.39-0.59), and became substantial to almost perfect when based on the average of 3 nights (ICC = 0.64-0.81). We observed similar degrees of stability for TST and WASO in the longitudinal sample, with moderate stability based on a single night and substantial stability based on both nights. In examining the persistence of "short" and "normal" sleep duration, 71.4% (controls), 74.7% (patients with insomnia), and 72.6% (longitudinal sample) of participants retained their first-night classifications over subsequent nights.

CONCLUSIONS:

Sleep duration variables, particularly total sleep time based on 3 consecutive nights in both patients with insomnia and controls or two single-night recordings separated by several years, are stable and reflect a person's habitual sleep. Furthermore, a single night in the laboratory may be useful for reliably classifying one's sleep duration.

KEYWORDS:

good sleepers; insomnia; polysomnography; sleep; stability

PMID:
26237768
PMCID:
PMC4813370
DOI:
10.5665/sleep.5152
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Silverchair Information Systems Icon for PubMed Central
Loading ...
Support Center