Effectiveness and moderators of cancer patient-caregiver dyad interventions in improving psychological distress: A systematic review and meta-analysis.

Objective: As patients and family caregivers are increasingly viewed as a dyadic whole, growing studies have emerged that identify ways to improve the two parties' emotional distress. However, the specific effectiveness, quality, and optimal intervention details of these studies are unclear. Our objective is to synthesize the effectiveness of existing dyadic interventions for improving the psychological distress of cancer patient-caregiver dyads and identify potential moderators that influence intervention effectiveness.

Methods: PubMed, Cochrane Library, Web of Science, CINHAL, Embase, and Clinical Trials were searched to identify all randomized controlled trials from inception until June 2021. Two reviewers performed the process independently. The Cochrane Risk of Bias tool was used for quality assessment. We calculated effect sizes (Hedges' adjusted ) by standard mean difference. Potential moderators influencing the intervention effects were explored.

Results: We included 28 articles, of which 12 were available for meta-analysis. In total, 4784 participants were included, who were primarily middle-aged ( ​= ​58 years old), with the highest proportion reporting a diagnosis of "mixed cancer" (30%). Patients' anxiety ( ​= ​-0.31; 95% : ​-0.51 to -0.12;  ​= ​0.001;  ​= ​17%) and cancer-related distress ( ​= ​-0.32; 95% : ​-0.46 to -0.18;  ​< ​0.0001;  ​= ​0%) were statistically significantly improved from baseline to post-intervention. Interventionist, delivery type, duration, and frequency were potential moderators for psychosocial interventions on negative emotions.

Conclusions: Face-to-face, relatively shorter interventions led by psychologists in moderator analysis seem to have better performance. Cancer dyad-based interventions were efficacious in improving the emotional distress of both parties in the dyad, but the effect was more apparent in patients than in family caregivers. However, the long-term effects were modest for both groups.