Life's Essential 8 and Incident Cardiovascular Disease in U.S. Women With Breast Cancer

Abstract

Background: Relationships between lifestyle risk factors and cardiovascular disease (CVD) risk in women with breast cancer (BC) are underexplored.

Objectives: To evaluate the incidence of CVD in relation to the Life's Essential 8 (LE8) score among women with BC.

Methods: Data from the Women's Health Initiative were utilized. The primary exposure was the LE8 score assessed prior to BC diagnosis. The LE8 score was stratified into low (0-59), moderate (60-79), and high (80-100) cardiovascular health (CVH). The primary endpoint was a composite of incident CVD events, which included coronary heart disease, defined as myocardial infarction along with coronary revascularization, CVD death, and stroke. We calculated the cumulative incidence of CVD and estimated hazard ratios.

Results: Among 7,165 participants, the median age was 70.1 years at BC diagnosis. The mean LE8 score was 62.0 ± 12.2. Over a median follow-up period of 6 years, 490 composite CVD events occurred. The risk of CVD events was highest for low CVH compared with moderate and high CVH. Compared with low CVH, the hazard ratio for incident CVD was 0.57 (95% CI: 0.46-0.69) for moderate CVH and 0.34 (95% CI: 0.20-0.59) for high CVH. LE8, in conjunction with age, provided a C-statistic of 0.74 for the composite risk of CVD.

Conclusions: Higher LE8 scores were associated with a lower risk of incident CVD among women with BC in the United States.

Keywords: behavioral risk factors; breast cancer; ischemic disease; lifestyle risk factors; women’s oncology.

Graphical abstract

Figure 1

Cumulative Incidence of CVD Events per CVH Category During a median follow-up period of 6.0 years (Q1-Q3: 3-9.3 years), a total of 490 composite cardiovascular disease (CVD) events occurred. Compared with individuals with low cardiovascular health (CVH), those with moderate and high CVH had a lower incidence of CVD (Gray’s test P < 0.001). The cumulative incidence at 10 years for CVD was 16.2%, 9.1%, and 1.5% for low, moderate, and high CVH, respectively. CHD = coronary heart disease.

Figure 2

Individual Components of LE8 Components and Risk of CVD When examining the association between each of the Life’s Essential 8 (LE8) components (excluding the lipid metric), nicotine exposure, blood glucose, and blood pressure were found to be significantly associated with risk of CVD. As compared with the reference score of 100, the lowest CVH status in nicotine exposure was associated with a HR of 1.83 (95% CI: 1.33-2.53), a HR of 1.94 (95% CI: 1.20-3.15) for blood glucose, and a HR of 1.94 (95% CI: 1.09-3.48) for blood pressure. In contrast, diet, physical activity, and sleep were not significantly associated with incident CVD. Abbreviations as in Figure 1.

Central Illustration

LE8 Score Predicts Incident CVD in Women with Breast Cancer Our study evaluated 7,165 postmenopausal women with breast cancer in the Women’s Health Initiative (WHI). Compared with women with breast cancer with a low cardiovascular health (CVH), those with moderate CVH and high CVH had a significantly lower risk of cardiovascular disease (CVD). A 10-point difference in Life’s Essential (LE8) scores was associated with a 21% lower risk of CVD. LE8, either as a categorical variable or as a continuous variable, provided a C-statistic of 0.74 for incident CVD when combined with age.