Social Ties Significantly Impact Survival of Patients With Breast Cancer

An exhaustive study conducted by researchers at the Kaiser Permanente Division of Research, Oakland, California, has found that a woman’s social network can significantly affect her chances of survival following breast cancer.

 

The study included more than 9000 women with breast cancer who were a part of the After Breast Cancer Pooling Project, and included women diagnosed with stages 1 to 4 invasive breast cancer. Data was collected and analyzed from breast cancer survivorship studies conducted in California, Utah, Oregon, Arizona, Texas, and Shanghai, China. Researchers examined how a range of lifestyle factors–including exercise, diet, weight management, and social factors–affect breast cancer survivorship. The study authors gathered data on social networks from these women within 2 years of their diagnosis. A social network index was derived for each participant using information such as the presence of a spouse/partner, religious ties, community ties, friendship ties, and numbers of living first-degree relatives. Stratification was by demographic, social, tumor, and treatment factors.

 

Over a median follow-up of 10.6 years, 1448 cancer recurrences and 1521 deaths (990 from breast cancer) were documented. Compared with socially integrated women, socially isolated women had:

• A 43% higher risk of recurrence (hazard ratio [HR], 1.43; 95% CI, 1.15-1.77)
• A 64% higher risk of dying specifically due to breast cancer (HR, 1.64; 95% CI, 1.33-2.03)
• A 69% higher risk of all-cause mortality (HR, 1.69; 95% CI, 1.43-1.99)

Of note, the associations were stronger in those with early-stage (1 or 2) cancer. Additionally, specific associations differed by age, race/ethnicity, and country of origin. For example, ties to relatives and friends predicted lower breast cancer—specific mortality in non-white women, whereas having a spouse predicted lower breast cancer—specific mortality in older white women. Ties within the community predicted better outcomes in older whites and those of Asian origin.

 

“It is well established that larger social networks predict lower overall mortality in healthy populations and in breast cancer patients, but associations with breast cancer—specific outcomes like recurrence and breast cancer mortality have been mixed,” said lead author Candyce H. Kroenke, ScD, MPH, a research scientist with the Kaiser Permanente Northern California Division of Research. “Our findings demonstrate the beneficial influence of women's social ties on breast cancer—specific outcomes, including recurrence and breast cancer death.”

 

Kroenke added that clinicians should assess information on social networks as a marker of prognosis and should consider that critical supports may differ by sociodemographic factors.

“Ultimately, this research may be able to help doctors tailor clinical interventions regarding social support for breast cancer patients based on the particular needs of women in different sociodemographic groups,” she said.

 

Reference

Post-diagnosis social networks and breast cancer mortality in the After Breast Cancer Pooling Project [published online December 12, 2016]. Cancer. doi: 10.1002/cncr.30440.