The effect of mindfulness meditation on sleep quality: a systematic review and meta-analysis of randomized controlled trials

Abstract

There is a growing interest in the effectiveness of mindfulness meditation for sleep disturbed populations. Our study sought to evaluate the effect of mindfulness meditation interventions on sleep quality. To assess for relative efficacy, comparator groups were restricted to specific active controls (such as evidenced-based sleep treatments) and nonspecific active controls (such as time/attention-matched interventions to control for placebo effects), which were analyzed separately. From 3303 total records, 18 trials with 1654 participants were included. We determined the strength of evidence using four domains (risk of bias, directness of outcome measures, consistency of results, and precision of results). At posttreatment and follow-up, there was low strength of evidence that mindfulness meditation interventions had no effect on sleep quality compared with specific active controls (ES 0.03 (95% CI -0.43 to 0.49)) and (ES -0.14 (95% CI -0.62 to 0.34)), respectively. Additionally, there was moderate strength of evidence that mindfulness meditation interventions significantly improved sleep quality compared with nonspecific active controls at postintervention (ES 0.33 (95% CI 0.17-0.48)) and at follow-up (ES 0.54 (95% CI 0.24-0.84)). These preliminary findings suggest that mindfulness meditation may be effective in treating some aspects of sleep disturbance. Further research is warranted.

Keywords: MBCT; MBSR; dose-response; insomnia; meditation; mindfulness; sleep.

Conflict of interest statement

Competing interests

The authors declare no competing interests.

Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

Figures

Figure 1.

Flow diagram from record identification to a final study inclusion.

Figure 2.

A-B Between-group relative percent difference in change score. Author, year, and sleep scale are noted at the bottom of each cluster bar. Follow-up scores are reported for trials with a follow-up assessment between 5 and 12 months from baseline. Percent change in sleep score was calculated using the formula: {[(postintervention mean^control – baseline mean^control) – (postintervention mean^meditation – baseline mean^meditation)] / (baseline mean^meditation)} × 100. Positive scores should be interpreted as relative percent change in favor of meditation. For example, a change score of 20% indicates the meditation group had a 20% higher improvement in sleep quality score compared with the control group. Dotted lines at −5% and 5% demarcate the effect threshold and do not indicate statistical significance. *The result is statistically significant per manuscript. [*]overall group effect is statistically significant; the effect for individual time points was not reported.

Figure 2.

A-B Between-group relative percent difference in change score. Author, year, and sleep scale are noted at the bottom of each cluster bar. Follow-up scores are reported for trials with a follow-up assessment between 5 and 12 months from baseline. Percent change in sleep score was calculated using the formula: {[(postintervention mean^control – baseline mean^control) – (postintervention mean^meditation – baseline mean^meditation)] / (baseline mean^meditation)} × 100. Positive scores should be interpreted as relative percent change in favor of meditation. For example, a change score of 20% indicates the meditation group had a 20% higher improvement in sleep quality score compared with the control group. Dotted lines at −5% and 5% demarcate the effect threshold and do not indicate statistical significance. *The result is statistically significant per manuscript. [*]overall group effect is statistically significant; the effect for individual time points was not reported.

Figure 3.

Random effects meta-analysis of the effect of mindfulness meditation on sleep quality at post-intervention, stratified by control type. The standardized mean difference was used as the summary effect estimate and was calculated as Hedges’g. Abbreviations: CI, confidence interval; IV, inverse variance; SD, standard deviation; Total, number of participants.

Figure 4.

Random effects meta-analysis of the effect of mindfulness meditation on sleep quality at a 5- to 12-month follow-up, stratified by control type. The standardized mean difference was used as the summary effect estimate and was calculated as Hedges’ g. Abbreviations: CI, confidence interval; IV, inverse variance; SD, standard deviation; Total, number of participants.