The dyadic paradox of unmet supportive care needs and depression in colorectal cancer couples: an explanatory sequential mixed-methods study

PurposeGuided by the Dyadic Coping Theory (DCT), this study aimed to investigate dyadic interrelationships between unmet supportive care needs (USCNs) and depression in colorectal cancer (CRC) patient-spousal caregiver dyads.MethodsUsing an explanatory sequential mixed-methods design, 200 CRC patient-caregiver dyads completed quantitative surveys. The Actor-Partner Interdependence Model (APIM) analyzed dyadic data. Subsequently, 10 dyads participated in semi-structured interviews, analyzed using reflexive thematic analysis.ResultsPatients reported significantly higher USCNs and depression. APIM revealed significant actor effects (unfulfilled needs predicted intrapersonal depression) but non-significant partner effects. Qualitative findings explained this phenomenon: couples employed “protective buffering” to conceal unfulfilled needs, inadvertently causing emotional isolation.ConclusionThe interrelationship between USCNs and depression in CRC dyads is driven by intrapersonal internalization rather than direct interpersonal transmission. Mutual protective buffering hinders open communication rather than directly transmitting distress. Care must transition to a dyad-centered approach, implementing couple-based communication interventions to dismantle protective buffering and alleviate mutual distress.