Christodoulou, G., & Black, D.S. (2017). Mindfulness-based interventions and sleep among cancer survivors: A critical analysis of randomized controlled trials. Current Oncology Reports, 19, 60-017-0621-6.

STUDY PURPOSE: Review and critically examine the literature that tests the efficacy of mindfulness-based interventions (MBIs) on sleep outcomes among cancer survivors.

TYPE OF STUDY: General review, "semi" systematic

DATABASES USED: Not stated

YEARS INCLUDED: (Overall for all databases) 2003-2015

INCLUSION CRITERIA: Randomized controlled trials that examine the efficacy of MBIs on sleep parameters that are primary or secondary outcomes of the study

EXCLUSION CRITERIA: Not stated

TOTAL REFERENCES RETRIEVED: Not stated 

EVALUATION METHOD AND COMMENTS ON LITERATURE USED: A specific appraisal or scoring system was not used, but the discussion addresses methodological strengths and limitations of the studies, including how researchers define sleep problems at baseline, whether sleep was a primary or secondary outcome of the trial, whether participants had completed cancer treatment, characteristics of control groups, and sleep measurement strategies.

FINAL NUMBER STUDIES INCLUDED: 6

TOTAL PATIENTS INCLUDED IN REVIEW: 695 participants 

SAMPLE RANGE ACROSS STUDIES: 35-336

KEY SAMPLE CHARACTERISTICS: Four trials had samples of breast cancer survivors, and two trials had patients with mixed diagnoses. Five of six trials required patients to have completed treatment, but three trials allowed patients to continue with hormone therapy. Participants in the trials had variable levels of sleep problems (low to high) at baseline.

PHASE OF CARE: Multiple phases of care  

APPLICATIONS: Elder care, palliative care

Four of six studies reported improvement in objective and/or subjective sleep measures immediately after the MBI. Three of six studies reported improvement in sleep at follow-up time points (1 month–3 months). Effect sizes were larger when participants had higher levels of sleep problems at baseline. Some trials included sleep as a secondary outcome when the primary outcomes were other conditions, such as depression, anxiety, and distress. It is not known, therefore, whether MBIs improved sleep directly or indirectly through improvement of the primary condition. It is difficult to measure dosage of MBIs.

The benefits of MBIs on sleep problems in cancer survivors are uncertain because of the variability in these trials.

Limited search

Limited number of studies included

High heterogeneity

The databases and the search strategy used are unknown. Only 6 studies were included. A specific appraisal system was not used.

Mindfulness practices have potential benefits to address a variety of distressing conditions, including cancer-related sleep disturbances. This review of six trials that tested the efficacy of MBIs on sleep disturbances in patients reported mixed results on sleep outcomes, concluding that the research was limited by variability in the trials. The discussion includes recommendations for strengthening this body of research.