**Table 2.** *Cont.*

 ER: estrogen receptor, PR: progesterone receptor status.

Multivariable models were adjusted for age, year of cancer diagnosis, race and ethnicity, disease stage, tumor size, and number of lymph nodes examined as these variables were found to be statistically significant in bivariable analyses. In these models, men with breast

cancer who received chemotherapy as part of their first course of treatment had elevated risk for CVD (Hazard ratio (HR): 1.32, 95% CI: 1.05–1.66)), with the risk being higher among those who received chemotherapy alone (HR: 1.55, 95% CI: 1.18–2.04) (Table 3).

**Table 3.** Hazard ratios and 95% confidence intervals for the association of cancer treatment with CVD mortality in men diagnosed with breast cancer, SEER registry (2000–2019).


Model 1: age adjusted model. Model 2: adjusted for age, year of cancer diagnosis, race and ethnicity, disease stage, tumor size, and number of lymph nodes examined. CI: confidence interval, HR: hazard ratio.

There was no significant association between radiotherapy (with or without chemotherapy) and CVD deaths. There was a significant interaction between race and ethnicity and cancer treatment on the risk of CVD mortality (*p* = 0.005). The risk of CVD mortality was observed to be highest among Hispanic men (HR: 3.96, 95% CI: 1.31–12.02) (Figure 1).

**Figure 1.** The association of cancer treatment with cardiovascular disease mortality in men diagnosed with breast cancer according to race and ethnicity, SEER registry (2000–2019). NH: Non-Hispanic. *p* value for interaction = 0.005.

Among persons who received radiotherapy, there was no significant influence of laterality or the association of radiotherapy and CVD mortality (*p* = 0.672). Similarly, the relation of radiotherapy and CVD mortality was not significantly influenced by the type of surgery, thus breast conservation surgery or mastectomy (*p* = 0.206).
