Lifestyle and Cardiovascular Risk Factors Associated With Heart Failure Subtypes in Postmenopausal Breast Cancer Survivors

Background

Breast cancer (BC) survivors experience an increased burden of long-term comorbidities, including heart failure (HF). However, there is limited understanding of the risk for the development of HF subtypes, such as HF with preserved ejection fraction (HFpEF), in BC survivors.

Objectives

This study sought to estimate the incidence of HFpEF and HF with reduced ejection fraction (HFrEF) in postmenopausal BC survivors and to identify lifestyle and cardiovascular risk factors associated with HF subtypes.

Methods

Within the Women’s Health Initiative, participants with an adjudicated diagnosis of invasive BC were followed to determine the incidence of hospitalized HF, for which adjudication procedures determined left ventricular ejection fraction. We calculated cumulative incidences of HF, HFpEF, and HFrEF. We estimated HRs for risk factors in relation to HF, HFpEF, and HFrEF using Cox proportional hazards survival models.

Results

In 2,272 BC survivors (28.6% Black and 64.9% White), the cumulative incidences of hospitalized HFpEF and HFrEF were 6.68% and 3.96%, respectively, over a median of 7.2 years (IQR: 3.6-12.3 years). For HFpEF, prior myocardial infarction (HR: 2.83; 95% CI: 1.28-6.28), greater waist circumference (HR: 1.99; 95% CI: 1.14-3.49), and smoking history (HR: 1.65; 95% CI: 1.01-2.67) were the strongest risk factors in multivariable models. With the exception of waist circumference, similar patterns were observed for HFrEF, although none were significant. In relation to those without HF, the risk of overall mortality in BC survivors with hospitalized HFpEF was 5.65 (95% CI: 4.11-7.76), and in those with hospitalized HFrEF, it was 3.77 (95% CI: 2.51-5.66).

Conclusions

In this population of older, racially diverse BC survivors, the incidence of HFpEF, as defined by HF hospitalizations, was higher than HFrEF. HF was also associated with an increased mortality risk. Risk factors for HF were largely similar to the general population with the exception of prior myocardial infarction for HFpEF. Notably, both waist circumference and smoking represent potentially modifiable factors.

Temporal Associations and Outcomes of Breast Cancer and Heart Failure in Postmenopausal Women

Background

Heart failure (HF) and breast cancer are 2 of the leading causes of death in postmenopausal women. The temporal association between HF and breast cancer in postmenopausal women has not been described.

Objectives

This study sought to examine the temporal association between HF and breast cancer.

Methods

Postmenopausal women within the WHI (Women's Health Initiative) cohort were studied. All prevalent HF and prevalent breast cancer at enrollment were self-reported. Incident hospitalized HF and breast cancer diagnoses were adjudicated through 2017.

Results

Among a cohort of 44,174 women (mean age 63 ± 7 years), 2,188 developed incident invasive breast cancer and 2,416 developed incident hospitalized HF over a median follow-up of 14 and 15 years, respectively. When compared with a breast cancer- and HF-free cohort, there was no association between prevalent HF and incident invasive breast cancer and similarly, there was no association between prevalent breast cancer and incident hospitalized HF. Across the entire cohort, the median survival after incident hospitalized HF was worse compared with an incident invasive breast cancer diagnosis (5 and 19 years, respectively). In women with incident invasive breast cancer, prevalent HF was associated with an increased risk of mortality (hazard ratio: 2.28; 95% confidence interval: 1.31 to 3.95). In women with incident hospitalized HF, prevalent breast cancer was associated with an increased risk of mortality (hazard ratio: 1.66; 95% confidence interval: 1.03 to 2.68). Cause of death after incident HF was different only in women with prevalent and interim breast cancer compared with those without prevalent and interim breast cancer.

Conclusions

In postmenopausal women, prevalent HF was not associated with a higher incidence of breast cancer and vice versa. However, the presence of incident invasive breast cancer or incident HF in those with prevalent HF or prevalent breast cancer, respectively, was associated with increased mortality.

Pre-Diagnosis Exercise and Cardiovascular Events in Primary Breast Cancer: Women's Health Initiative

Objectives

The purpose of this study was to investigate whether pre-diagnosis exercise reduces the risk of subsequent cardiovascular events (CVEs) in women with primary breast cancer.

Background

Cardiovascular disease (CVD) is the leading nonmalignant cause of death in patients with cancer, and it is the leading cause of death in women with primary breast cancer who are older than 65 years of age.

Methods

Using a prospective design, 4,015 patients with confirmed diagnosis of primary breast cancer enrolled in the Women’s Health Initiative (WHI) completed a self-report questionnaire assessing leisure-time physical activity (i.e., exercise) in metabolic equivalent task (MET) hours per week. Age- and multivariable-adjusted Cox proportional hazards models were used to estimate associations between pre-diagnosis exercise and new-onset CVEs (i.e., heart failure [HF], myocardial infarction [MI], angina, coronary revascularization, peripheral arterial disease [PAD], carotid artery disease, transient ischemic attack [TIA], stroke, and cardiovascular death).

Results

Median follow-up was 12.7 years and 8.2 years for cardiovascular disease (CVD) mortality and CVEs, respectively, with 324 CVEs, including 89 MIs, 49 new diagnoses of HF, and 215 CVD deaths. In multivariable analysis, the incidence of composite CVEs decreased across increasing total MET h/week categories (p = 0.016). Compared with <2.5 MET-hours per week, the adjusted hazard ratio (HR) was 0.80 (95% confidence interval [CI]: 0.59 to 1.09) for 2.5 to <8.6 MET h/week; 0.9 (95% CI: 0.64 to 1.17) for 8.6 to <18 MET h/week; and 0.63 (95% CI: 0.45 to 0.88) for ≥18 MET h/week.

Conclusion

Pre-diagnosis exercise exposure is associated with a significant graded reduction in subsequent CVEs in long-term survivors of primary breast cancer.