Effective non-pharmacological interventions for cancer related cognitive impairment in adults (excluding central nervous system or head and neck cancer): systematic review and meta-analysis

Cancer-related cognitive impairment (CRCI) is prevalent in cancer survivors, and impairments affect daily living tasks and overall wellbeing. This review aimed to identify and evaluate published randomized controlled trials (RCTs) of interventions to manage CRCI in adult populations, to analyze their effectiveness and to investigate the quality of the studies.Seven databases were searched (Medline, Scopus, CINAHL, AMED, PsychINFO, OTseeker, and the Cochrane Database of Systematic Reviews), including years 2005-2020, for randomized controlled trials (RCTs) investigating interventions to address cognition for adults with cancer. The final search was conducted in February 2021. The quality of studies was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for RCTs. Meta-analysis used comprehensive meta-analysis software. The study protocol was registered with PROSPERO (registration N. CRD42017076868).A total of 45 studies involving 4727 participants examined interventions for CRCI and met selection criteria. Categories of interventions included cognitive training-based intervention (N.=15), cognitive behavior therapy (CBT) (N.=4), physical activity (N.=16) and other supportive therapies (N.=10). Meta-analysis indicated beneficial overall effects for all categories of interventions: cognitive training (standardized mean difference [SMD]=0.41, 95% CI: 0.28-0.53, I2=88.87%); CBT (SMD=0.30, 95% CI: 0.14-0.46, I2=44.86%); physical activity (SMD=0.27, 95% CI: 0.20-0.35, I2=37.67%); and supportive therapies (SMD=0.27, 95% CI: 0.16-0.39, I2=64.94%). Studies used self-report cognitive outcome measures and neurocognitive testing, or a mixture.Findings suggest that effective intervention for CRCI exist, and cognitive training is consistently supported as an effective intervention; however, a high level of heterogeneity was found. CRCI research is currently dominated by breast cancer survivors, and quality research is also needed to address the broader population of cancer survivors who experience CRCI.