Psychological interventions for women with non-metastatic breast cancer

Background: Breast cancer is the most common cancer affecting women worldwide. It is a distressing diagnosis and, as a result, considerable research has examined the psychological sequelae of being diagnosed and treated for breast cancer. Breast cancer is associated with increased rates of depression and anxiety and reduced quality of life. As a consequence, multiple studies have explored the impact of psychological interventions on the psychological distress experienced after a diagnosis of breast cancer. This review is an update of a Cochrane Review first published in 2015.

Objectives: To assess the effect of psychological interventions on psychological morbidities and quality of life among women with non-metastatic breast cancer. SEARCH METHODS: We searched the Cochrane Breast Cancer Group Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO, the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) and ClinicalTrials.gov up to 16 March 2021. We also scanned the reference lists of relevant articles.

Selection criteria: Randomised controlled trials that assessed the effectiveness of psychological interventions for women with non-metastatic breast cancer.

Data collection and analysis: Two review authors independently appraised, extracted data from eligible trials, and assessed risk of bias and certainty of the evidence using the GRADE approach. Any disagreement was resolved by discussion. Extracted data included information about participants, methods, the intervention and outcomes.

Main results: We included 60 randomised controlled trials comprising 7998 participants. The most frequent reasons for exclusion were non-randomised trials and the inclusion of women with metastatic disease. The updated review included 7998 randomised women; the original review included 3940 women. A wide range of interventions was evaluated. Most interventions were cognitive- or mindfulness-based, supportive-expressive, and educational. The interventions were mainly delivered face-to-face (56 studies) and in groups (50 studies) rather than individually (10 studies). Most intervention sessions were delivered on a weekly basis with an average duration of 14 hours. Follow-up time ranged from two weeks to 24 months. Pooled standardised mean differences (SMD) from baseline indicated that the intervention may reduce depression (SMD -0.27, 95% confidence interval (CI) -0.52 to -0.02; P = 0.04; 27 studies, 3321 participants, I² = 91%, low-certainty evidence); anxiety (SMD -0.43, 95% CI -0.68 to -0.17; P = 0.0009; 22 studies, 2702 participants, I² = 89%, low-certainty evidence); mood disturbance in the intervention group (SMD -0.18, 95% CI -0.31 to -0.04; P = 0.009; 13 studies, 2276 participants, I² = 56%, low-certainty evidence); and stress (SMD -0.34, 95% (CI) -0.55 to -0.12; P = 0.002; 8 studies, 564 participants, I² = 31%, low-certainty evidence). The intervention is likely to improve quality of life in the intervention group (SMD 0.78, 95% (CI) 0.32 to 1.24; P = 0.0008; 20 studies, 1747 participants, I² = 95%, low-certainty evidence). Adverse events were not reported in any of the included studies.

Authors' conclusions: Based on the available evidence, psychological intervention may have produced favourable effects on psychological outcomes, in particular depression, anxiety, mood disturbance and stress. There was also an improvement in quality of life in the psychological intervention group compared to control group. Overall, there was substantial variation across the studies in the range of psychological interventions used, control conditions, measures of the same outcome and timing of follow-up.