Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Randomized Controlled Trial
. 2017 Nov 15;13(11):1243-1254.
doi: 10.5664/jcsm.6790.

Night-to-Night Sleep Variability in Older Adults With Chronic Insomnia: Mediators and Moderators in a Randomized Controlled Trial of Brief Behavioral Therapy (BBT-I)

Wai Sze Chan  1 , Jacob Williams  2 , Natalie D Dautovich  3 , Joseph P H McNamara  4 , Ashley Stripling  5 , Joseph M Dzierzewski  3 , Richard B Berry  6 , Karin J M McCoy  7 , Christina S McCrae  8
Affiliations
Randomized Controlled Trial

Night-to-Night Sleep Variability in Older Adults With Chronic Insomnia: Mediators and Moderators in a Randomized Controlled Trial of Brief Behavioral Therapy (BBT-I)

Wai Sze Chan et al. J Clin Sleep Med. .

Abstract

Study objectives: Sleep variability is a clinically significant variable in understanding and treating insomnia in older adults. The current study examined changes in sleep variability in the course of brief behavioral therapy for insomnia (BBT-I) in older adults who had chronic insomnia. Additionally, the current study examined the mediating mechanisms underlying reductions of sleep variability and the moderating effects of baseline sleep variability on treatment responsiveness.

Methods: Sixty-two elderly participants were randomly assigned to either BBT-I or self-monitoring and attention control (SMAC). Sleep was assessed by sleep diaries and actigraphy from baseline to posttreatment and at 3-month follow-up. Mixed models were used to examine changes in sleep variability (within-person standard deviations of weekly sleep parameters) and the hypothesized mediation and moderation effects.

Results: Variabilities in sleep diary-assessed sleep onset latency (SOL) and actigraphy-assessed total sleep time (TST) significantly decreased in BBT-I compared to SMAC (Pseudo R2 = .12, .27; P = .018, .008). These effects were mediated by reductions in bedtime and wake time variability and time in bed. Significant time × group × baseline sleep variability interactions on sleep outcomes indicated that participants who had higher baseline sleep variability were more responsive to BBT-I; their actigraphy-assessed TST, SOL, and sleep efficiency improved to a greater degree (Pseudo R2 = .15 to .66; P < .001 to .044).

Conclusions: BBT-I is effective in reducing sleep variability in older adults who have chronic insomnia. Increased consistency in bedtime and wake time and decreased time in bed mediate reductions of sleep variability. Baseline sleep variability may serve as a marker of high treatment responsiveness to BBT-I.

Clinical trial registration: ClinicalTrials.gov, Identifier: NCT02967185.

Keywords: CBT-I; insomnia; mechanisms of change; older adults; sleep variability; treatment efficacy moderator.

PubMed Disclaimer

Figures

Figure 1
Figure 1. CONSORT flow diagram.
BBT-I, brief behavioral therapy for insomnia; LOCF, last observation carried forward, Obs, observation, SMAC, self-monitoring and attention control.
Figure 2
Figure 2. Significant time × group interactions.
Significant time × group interactions on (A) sleep diary-assessed sleep onset latency variability (varSOLs) and (B) actigraphy-assessed total sleep time variability (varTSTa). BBT-I = brief behavioral therapy for insomnia, SMAC = self-monitoring and attention control.
Figure 3
Figure 3. Significant time × group interactions.
Significant time × group interactions on (A) variability in bedtime (varBT), (B) variability in wake time (varWT), and (C) time in bed (TIB). BBT-I = brief behavioral therapy for insomnia, SMAC = self-monitoring and attention control.
Figure 4
Figure 4. Significant time × group × baseline sleep variability interactions.
Significant time × group × baseline sleep variability interactions on (A) sleep diary-assessed sleep onset latency (SOLs), (B) actigraphy-assessed sleep onset latency (SOLa), (C) actigraphy-assessed total sleep time (TSTa), and (D) actigraphy-assessed sleep efficiency (SEa). B_varSEa = baseline variability of SEa, B_varSOLa = baseline variability of SOLa, B_varSOLs = baseline variability of SOLs, B_varTSTa = baseline variability of TSTa, BBT-I = brief behavioral therapy for insomnia, SMAC = self-monitoring and attention control.
See this image and copyright information in PMC

References

    1. Mallon L, Broman JE, Hetta J. Relationship between insomnia, depression, and mortality: a 12-year follow-up of older adults in the community. Int Psychogeriatr. 2000;12(3):295–306. - PubMed
    1. Stewart R, Besset A, Bebbington P, et al. Insomnia comorbidity and impact and hypnotic use by age group in a national survey population aged 16 to 74 years. Sleep. 2006;29(11):1391–1397. - PubMed
    1. Ohayon MM. Epidemiology of insomnia: what we know and what we still need to learn. Sleep Med Rev. 2002;6(2):97–111. - PubMed
    1. Baron KG, Reid KJ, Malkani RG, Kang J, Zee PC. Sleep variability among older adults with insomnia: associations with sleep quality and cardiometabolic disease risk. Behav Sleep Med. 2017;15(2):144–157. - PMC - PubMed
    1. Buysse DJ, Cheng Y, Germain A, et al. Night-to-night sleep variability in older adults with and without chronic insomnia. Sleep Med. 2010;11(1):56–64. - PMC - PubMed

Publication types

Associated data