Interdependence of physical and psychological morbidity among patients with cancer and family caregivers: Review of the literature.

OBJECTIVE: Caregivers for patients with cancer have an integral role in maintaining patients' health. Although patients and caregivers experience the impact of cancer individually, studies suggest their health is interdependent. The objective of this review was to synthesize the literature on interdependent physical and psychological morbidity in patient-caregiver dyads published since 2016. METHODS: A search of PubMed, CINAHL, Embase, and PsycInfo databases was performed using Cooper's recommendations and the Preferred Reporting Items for Systematic Reviews And Meta-Analyses Guidelines. Studies were included if they measured individual physical or psychological morbidity in cancer patient-caregiver dyads, evaluated interdependence, and were published in a peer-reviewed journal. RESULTS: Twenty-three studies met criteria, characterized by mainly spousal dyads. Studies included a variety of cancers and methodologies. Findings were inconsistent, indicating varying interdependence. However, the studies demonstrated a stronger relationship between patients' and caregivers' psychological morbidity than between their physical morbidity. CONCLUSIONS: This review revealed a need for continued exploration of dyadic health interdependence. Future studies should consider samples of patients with a single type of cancer, testing cultural mediators/moderators, and using longitudinal designs.