Socially isolated breast cancer survivors have higher rates of recurrence and mortality than women with larger social networks, according to a study published online December 12 in Cancer.
The fact that larger social networks predict lower overall mortality in healthy populations and in breast cancer patients has been demonstrated, but associations with breast cancer-specific outcomes such as recurrence and breast cancer mortality have been mixed, wrote lead author Candyce Kroenke, ScD, of the Kaiser Permanente Division of Research in Oakland, CA, and colleagues. Kroenke's group evaluated data from 9,267 women with breast cancer to see how their social networks might affect their survival over two years following their diagnosis (Cancer, December 12, 2016).
Of the women included in the study, there were 1,448 cancer recurrences and 1,521 deaths, 990 of which were from breast cancer. Compared with women who had active social networks, those who were more socially isolated had a 40% higher risk of recurrence, a 60% higher risk of dying from breast cancer, and a 70% higher risk of dying from any cause; these associations were stronger in those with stage I or II cancer.
Age, race/ethnicity, and country of origin also affected outcomes. For example, ties to relatives and friends predicted lower breast cancer-specific mortality in nonwhite women, having a spouse predicted lower breast cancer-specific mortality in older white women, and community ties predicted better outcomes in older whites and Asians.
Kroenke and colleagues urged clinicians to assess patients' social connections as a marker of prognosis, and to consider that patients' support systems may differ by sociodemographic factors.
"These findings, from a large pooled cohort of nearly 10,000 women with breast cancer, confirm the generally beneficial influence of women's social ties on breast cancer recurrence and mortality," Kroenke said in a statement released by Wiley, Cancer's publisher. "However, they also point to complexity: that not all social ties are beneficial, and not in all women."