Treanor, C.J., McMenamin, U.C., O'Neill, R.F., Cardwell, C.R., Clarke, M.J., Cantwell, M., & Donnelly, M. (2016). Non-pharmacological interventions for cognitive impairment due to systemic cancer treatment. Cochrane Database of Systematic Reviews, 8, CD011325.
STUDY PURPOSE: To determine the effectiveness of nonpharmacologic interventions for minimizing chemotherapy-induced cognitive impairment in adult patients with breast cancer.
TYPE OF STUDY: Systematic review
DATABASES USED: MEDLINE, Embase, PubMed, CINAHL, PsycINFO, and CENTRAL (Cochrane Centre Register of Controlled Trials)
YEARS INCLUDED: (Overall for all databases) 1980 through September 29, 2015
INCLUSION CRITERIA: Randomized controlled trials evaluating the effectiveness of nonpharmacologic interventions on maintaining or improving cognitive function in cancer survivors who completed chemotherapy (including those currently on hormonal therapy)
EXCLUSION CRITERIA: Studies involving participants with primary or metastatic central nervous system (CNS) disease, nonmelanoma skin cancer, and/or patients in nursing home or residential care settings
TOTAL REFERENCES RETRIEVED: 255 screened (plus 47 additional records), but 40 assessed for study eligibility
EVALUATION METHOD AND COMMENTS ON LITERATURE USED: Cochrane risk of bias tool was utilized to evaluate study quality.
FINAL NUMBER STUDIES INCLUDED: 5
TOTAL PATIENTS INCLUDED IN REVIEW: 235
SAMPLE RANGE ACROSS STUDIES: 100% female; all patients received chemotherapy and/or hormonal therapy
KEY SAMPLE CHARACTERISTICS: Breast cancer survivors
PHASE OF CARE: Transition phase after active treatment
Five randomized clinical trials compared an intervention with wait-list controls to improve various cognitive functions (i.e., memory, information processing speed [IPS], executive functioning [EF]). Nonpharmacologic interventions included cognitive behavioral therapy (n = 1), cognitive training (n = 2), meditation through Tibetan sound therapy (n = 1), and aerobic exercise (n = 1).
Although cognitive training and cognitive behavioral therapy may be beneficial in improving cognitive functioning, there is insufficient evidence for exercise and meditation. The overall quality of the evidence was determined to be low for all studies included.
Findings from this study revealed that there is insufficient good-quality evidence to determine whether cognitive training, cognitive behavioral interventions, exercise, or meditation may improve cognitive functioning in breast cancer survivors who have received chemotherapy with or without hormonal therapy. However, cognitive training and cognitive behavioral interventions were associated with improvements in objective and subjective measures of cognitive function, so further research including multisite studies with large sample sizes and higher-quality evidence may confirm their effectiveness. Further studies are needed to determine whether exercise and/or meditation might have a role in alleviating cognitive impairment.
Limited number of studies included
Mostly low quality/high risk of bias studies
Study findings do not support recommending cognitive training, cognitive behavioral interventions, exercise, or meditation for improving cognitive impairment in breast cancer survivors. However, additional research using these interventions are recommended to further determine their effectiveness.