Social networks and survival after breast cancer diagnosis.
BACKGROUND
Evidence has been inconsistent regarding the impact of social networks on survival after breast cancer diagnosis. We prospectively examined the relation between components of social integration and survival in a large cohort of breast cancer survivors.


METHODS
Women (N=4,589) diagnosed with invasive breast cancer were recruited from a population-based, multi-center, case-control study. A median of 5.6 years (Interquartile Range 2.7-8.7) after breast cancer diagnosis, women completed a questionnaire on recent post-diagnosis social networks and other lifestyle factors. Social networks were measured using components of the Berkman-Syme Social Networks Index to create a measure of social connectedness. Based on a search of the National Death Index, 552 deaths (146 related to breast cancer) were identified. Adjusted hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox proportional hazards regression.


RESULTS
Higher scores on a composite measure of social connectedness as determined by the frequency of contacts with family and friends, attendance of religious services, and participation in community activities was associated with a 15-28% reduced risk of death from any cause (p-trend=0.02). Inverse trends were observed between all-cause mortality and frequency of attendance at religious services (p-trend=0.0001) and hours per week engaged in community activities (p-trend=0.0005). No material associations were identified between social networks and breast cancer-specific mortality.


CONCLUSIONS
Engagement in activities outside the home was associated with lower overall mortality after breast cancer diagnosis.
Beasley
Jeannette M
JM
Cancer Prevention Program, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., M3-A410, Seattle, WA 98109-1024, USA.
Newcomb
Polly A
PA
Trentham-Dietz
Amy
A
Hampton
John M
JM
Ceballos
Rachel M
RM
Titus-Ernstoff
Linda
L
Egan
Kathleen M
KM
Holmes
Michelle D
MD
D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis / Q000401:mortality* / Q000523:psychology / Q000534:rehabilitation; D002277:Carcinoma / Q000175:diagnosis / Q000401:mortality* / Q000523:psychology / Q000534:rehabilitation; D016022:Case-Control Studies; D002423:Cause of Death; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D012944:Social Support; D012959:Socioeconomic Factors; D016019:Survival Analysis