Associations of social networks with cancer mortality: a meta-analysis.

This meta-analysis integrates results of 87 studies on the associations of perceived social support, network size, and marital status with cancer survival. In controlled studies, having high levels of perceived social support, larger social network, and being married were associated with decreases in relative risk for mortality of 25%, 20%, and 12%, respectively. Moderator analyses revealed that never married patients had higher mortality rates than widowed and divorced/separated patients. Associations of social network with mortality were stronger in younger patients, and associations of marital status with mortality were stronger in studies with shorter time intervals, and in early-stage cancer. Relationships varied by cancer site, with stronger associations of social support observed in studies of patients with leukemia and lymphomas and stronger associations of network size observed in studies of breast cancer. Further randomized intervention studies are needed to test causal hypotheses about the role of social support and social network for cancer mortality. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.