Digital health behaviour change interventions targeting physical activity and diet in cancer survivors: a systematic review and meta-analysis

Purpose: The number of cancer survivors has risen substantially due to improvements in early diagnosis and treatment. Health behaviours such as physical activity (PA) and diet can reduce recurrence and mortality, and alleviate negative consequences of cancer and treatments. Digital behaviour change interventions (DBCIs) have the potential to reach large numbers of cancer survivors. Methods: We conducted a systematic review and meta-analyses of relevant studies identified by a search of Medline, EMBASE, PubMed and CINAHL. Studies which assessed a DBCI with measures of PA, diet and/or sedentary behaviour were included. Results: 15 studies were identified. Random effects meta-analyses showed significant improvements in moderate-vigorous PA (7 studies; mean difference (MD) = 41 minutes per week; 95% CI: 12, 71) and body mass index (BMI)/weight (standardised mean difference (SMD) = -0.23; 95% CI: -0.41, -0.05). There was a trend toward significance for reduced fatigue and no significant change in cancer-specific quality of life (QoL). Narrative synthesis revealed mixed evidence for effects on diet, generic QoL and self-efficacy and no evidence of an effect on mental health. Two studies suggested improved sleep quality. Conclusions: DBCIs may improve PA and BMI among cancer survivors and there is mixed evidence for diet. The number of included studies is small and risk of bias and heterogeneity was high. Future research should address these limitations with large, high-quality RCTs, with objective measures of PA and sedentary time. Implications for cancer survivors: Digital technologies offer a promising approach to encourage health behaviour change among cancer survivors

Effects and mediators of a web-based tailored intervention for cancer survivors on quality of life, anxiety, depression, and fatigue

Background: Many cancer survivors face difficulties affecting their quality of life, of which anxiety, depression, and fatigue are prominent issues. Therefore, the web-based computer-tailored 'Kanker Nazorg Wijzer' intervention (KNW; Cancer Aftercare Guide) was developed, a self-management tool aimed at increasing survivors' psychosocial well-being. Methods: As part of a randomized controlled trial comparing a waiting list control group (n=231) with an intervention group (n=231), the effectiveness of the KNW on quality of life (EORTC QLQ-C30), anxiety and depression (HADS), and fatigue (CIS) was assessed at 6 and 12 months from baseline using multilevel linear regression analyses. Theoretically hypothesized mediators, measured at 3 months from baseline, were problem solving skills (SPSI-R) and personal control (IPQ-R). Mediation analyses were conducted with Hayes' PROCESS macro. Results: At 6 months from baseline, the KNW was effective in reducing depression and fatigue. In addition, effects were found for emotional and social functioning, although these effects were less strong. At 12 months from baseline, the effects were not statistically significant. Mediation analyses, with depression and fatigue at 6 months from baseline as outcomes, showed that personal control mediated the effects of depression and fatigue. There was no evidence for problem solving skills as mediator. Conclusions: The KNW can be considered as an effective intervention (at short-term), low-intensive, and easy accessible intervention that expedites cancer recovery, partly through changing personal control. Therefore, it might serve as a first step in stepped care for initial psychosocial support after cancer treatment