Association of marital status with cardiovascular outcome in patients with breast cancer

BACKGROUND: The influences of marital status on cardiovascular death risk in patients with breast cancer remained unclear. This study aimed to evaluate the associations of different marital status with cardiovascular death risk in patients with breast cancer. METHODS: A total of 182,666 female breast cancer patients were enrolled in this study from the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2014, and was divided into two groups: married (N=107,043) and unmarried (N=75,623). A 1:1 propensity score matching (PSM) was applied to reduce inter-group bias between the two groups. Competing-risks model was used to assess the associations between different marital status and cardiovascular death risk in patients with breast cancer. RESULTS: After PSM, marital status was an independent predictor for cardiovascular death in patients with breast cancer. Unmarried condition was associated with increased cardiovascular death risk than married condition among breast cancer patients [unadjusted model: hazard ratio (HR) =2.012, 95% confidence interval (CI): 1.835–2.208, P<0.001; Model 1: HR =1.958, 95% CI: 1.785–2.148, P<0.001; Model 2: HR =1.954, 95% CI: 1.781–2.144, P<0.001; Model 3: HR =1.920, 95% CI: 1.748–2.107, P<0.001]. With the exception of separated condition (adjusted HR =0.886, 95% CI: 0.474–1.658, P=0.705), further unmarried subgroups analysis showed that the other three unmarried status were associated with increased cardiovascular death risk as follows: single (adjusted HR =1.623, 95% CI: 1.421–1.853, P<0.001), divorced (adjusted HR =1.394, 95% CI: 1.209–1.608, P<0.001), and widowed (adjusted HR =2.460, 95% CI: 2.227–2.717, P<0.001). In particularly, widowed condition showed the highest cardiovascular death risk in all 4 unmarried subgroups. CONCLUSIONS: Unmarried condition (e.g., single, divorced and widowed) was associated with elevated cardiovascular death risk compared with their married counterparts in patients with breast cancer, suggesting that more attention and humanistic care should be paid to unmarried breast cancer patients (especially the widowed patients) in the management of female breast cancer patients.