biostudies-literatureWang CNational Natural Science Foundation of ChinaForskningsrådet om Hälsa, Arbetsliv och VälfärdFull-time Postdoc Research and Development Foundation of West China Hospital1450-1458https://www.ebi.ac.uk/biostudies/studies/S-EPMC8575780biostudies-literatureUnknown125(10)<h4>Background</h4>To assess the risk of cardiovascular mortality among cancer survivors who developed breast cancer as a second malignancy (BCa-2) compared with patients with first primary breast cancer (BCa-1) and the general population.<h4>Methods</h4>Using the Surveillance, Epidemiology, and End Results database, we conducted a population-based cohort study including 1,024,047 BCa-1 and 41,744 BCa-2 patients diagnosed from the age 30 between 1975 and 2016, and the corresponding US female population (994,415,911 person-years; 5,403,551 cardiovascular deaths). Compared with the general population and BCa-1 patients, we calculated incidence rate ratios (IRRs) of cardiovascular deaths among BCa-2 patients using Poisson regression. To adjust for unmeasured confounders, we performed a nested, case-crossover analysis among BCa-2 patients who died from cardiovascular disease.<h4>Results</h4>Although BCa-2 patients had a mildly increased risk of cardiovascular mortality compared with the population (IRR 1.08) and BCa-1 patients (IRR 1.15), the association was pronounced among individuals aged 30-49 years (BCa-2 vs. population: IRR 6.61; BCa-2 vs. BCa-1: IRR 3.03). The risk elevation was greatest within the first month after diagnosis, compared with the population, but comparable with BCa-1 patients. The case-crossover analysis confirmed these results.<h4>Conclusion</h4>Our findings suggest that patients with BCa-2 are at increased risk of cardiovascular mortality.British journal of cancerCardiovascular mortality among cancer survivors who developed breast cancer as a second primary malignancy.PMC8575780818723072018-00648Wang CFang FLu DHu KDeng LFall KLuo CTamimi RMValdimarsdottir UAfalseCardiovascular mortality among cancer survivors who developed breast cancer as a second primary malignancy.<h4>Background</h4>To assess the risk of cardiovascular mortality among cancer survivors who developed breast cancer as a second malignancy (BCa-2) compared with patients with first primary breast cancer (BCa-1) and the general population.<h4>Methods</h4>Using the Surveillance, Epidemiology, and End Results database, we conducted a population-based cohort study including 1,024,047 BCa-1 and 41,744 BCa-2 patients diagnosed from the age 30 between 1975 and 2016, and the corresponding US female population (994,415,911 person-years; 5,403,551 cardiovascular deaths). Compared with the general population and BCa-1 patients, we calculated incidence rate ratios (IRRs) of cardiovascular deaths among BCa-2 patients using Poisson regression. To adjust for unmeasured confounders, we performed a nested, case-crossover analysis among BCa-2 patients who died from cardiovascular disease.<h4>Results</h4>Although BCa-2 patients had a mildly increased risk of cardiovascular mortality compared with the population (IRR 1.08) and BCa-1 patients (IRR 1.15), the association was pronounced among individuals aged 30-49 years (BCa-2 vs. population: IRR 6.61; BCa-2 vs. BCa-1: IRR 3.03). The risk elevation was greatest within the first month after diagnosis, compared with the population, but comparable with BCa-1 patients. The case-crossover analysis confirmed these results.<h4>Conclusion</h4>Our findings suggest that patients with BCa-2 are at increased risk of cardiovascular mortality.2021-01-01T00:00:00Z2021 Nov2025-04-18T20:58:15.82Z2025-02-19T01:57:20.784ZS-EPMC85757803458043110.1038/s41416-021-01549-w