It's Not All About that Base Weight: Chipping the Glass Ceiling of Women's Cardiovascular Health

As medicine moves toward a more precise, individualized approach, recognizing differences in cardiovascular disease (CVD) development, presentation, diagnosis and treatment across sexes, genders, the lifespan, and ethnic groups is vitally important. Gender‐specific analysis and recommendations for CVD such as heart failure and coronary artery disease are becoming increasingly common, recognizing the need for gender‐specific monitoring, diagnoses and treatment strategies, ¹ , ² , ³ and repeated calls to action for improving CVD among women. ⁴ , ⁵

Traditionally, identifying individuals at greater risk of CVD has employed risk identification strategies such as metabolic syndrome diagnoses or American Heart Association/American College of Cardiology atherosclerotic risk score assessments, which identify individuals at risk based primarily on measures of body size, cholesterol levels, and blood sugar levels. ⁶ , ⁷ Although these measures are objective, significant behavioral risk factors also influence experiences of CVD for women. ⁸

A greater prevalence of metabolic syndrome among women compared with men has been identified, which has increased over the past several decades. ⁶ , ⁹ Further, the effects of traditional risk factors on CVD experiences on women differ from that of men, including smoking, obesity, and sedentary behavior, to name a few. ⁶ , ⁹ Among women, these modifiable risk factors comprise 94% of the population‐attributable risks of myocardial infarction, highlighting the vital importance of a healthy lifestyle in reducing CVD risks for women. ⁸ , ¹⁰

In addition to traditional risk factors, lifestyle factors are increasingly identified as important contributors to experiences of CVD among women. ⁸ , ¹¹ Smoking, alcohol intake, diet, and physical activity have commonly been identified as important health determining behaviors, though body size or obesity continues to be a major focus of lifestyle risk factors for CVD. ⁸ , ¹² , ¹³ The importance of body size as a risk factor for CVD and all‐cause mortality in past research, coupled with weight bias and stigma among health care professionals leads to a focus on body size and can lead to overlooking individuals who present with a healthy body mass index (BMI). ¹⁴ , ¹⁵ Recognizing women of healthy BMI who are at increased risk for CVD is an important aspect of continuing improvements in rates of CVD for all women. ⁴

In the article by Peila et al in this issue of the Journal of the American Heart Association (JAHA), they present analysis from their Women's Health Initiative trial evaluating a healthy lifestyle index to identify risk factors for CVD among postmenopausal women with normal BMI. ¹⁶ They evaluated 40 118 women in the United States aged 50 to 79 years at enrollment with no history of CVD at enrollment for a median 20.1 year follow‐up (9.1–22.9 years) to March 2020. Primary outcomes evaluated at follow‐up included 3821 incidents of CVD, comprised of 1472 cases of coronary heart disease (CHD) (including 1076 cases of myocardial infarction), 1304 coronary revascularizations (596 concurrent with CHD, 42 simultaneous with stroke), 643 cases of angina (72 with concurrent CHD, 40 with simultaneous stroke), and 1436 cases of stroke (151 with simultaneous CHD). They evaluated associations of primary outcomes with a healthy lifestyle index, as described in supplemental Table S1, comprised of scores from 0–4 for each of diet (range: Alternative Healthy Eating Index 2010 ¹⁷ scores <45.6=0 through ≥63.4=4), alcohol consumption (0 drinks/day=0, >0 to <0.5 drinks/day=1, ≥2 drinks/day=2, 1 to <2 drinks/day=3, 0.5 to 1 drinks/day=4), smoking (range: never smoked=4 through current smoker >15 pack‐years=0), healthy waist circumference (range: <69.1 cm=4 through ≥80.1 cm=0), and moderate or vigorous physical activity (range: ≤2.5 metabolic equivalent hours/week=0 through >25.7 metabolic equivalent hours/week=4). Important findings from this study identified higher scores on this composite healthy lifestyle index were associated with substantially lower CVD incidence beyond having a healthy body weight. Even among these women of normal BMI, as outlined in Table 2, the 5 lifestyle factors combined were associated with lower incidence of CVD (adjusted hazard ratio [HR], 0.48 [95% CI, 0.43–0.54]), including CHD (adjusted HR, 0.38 [95% CI, 0.32–0.45]), myocardial infarction (adjusted HR, 0.40 [95% CI, 0.33–0.49]), stroke (adjusted HR, 0.64 [95% CI, 0.57–0.76]), angina (adjusted HR, 0.46 [95% CI, 0.35–0.61]), and coronary revascularization (adjusted HR, 0.41 [95% CI, 0.34–0.49]) among the fifth quintile (Q5) with the highest healthy lifestyle index scores compared to the reference quintile (Q1) with the lowest scores. Further, as outlined in Table 3, this decreased incidence of CVD was found across women who do not undergo hormone replacement therapy (Q5 adjusted HR, 0.49 [95% CI, 0.44–0.55]), younger women (≤63 years and younger, Q5 adjusted HR, 0.43 [95% CI, 0.36–0.52]), older women (>63 years, Q5 adjusted HR, 0.52 [95% CI, 0.46–0.59]), women without diabetes, hypertension, or taking antihypertensive or lipid‐lowering medications (Q5 adjusted HR, 0.49 [95% CI, 0.43–0.57]), and, as outlined on supplementary Table S5, among women experiencing restless (Q5 adjusted HR, 0.51 [95% CI, 0.38–0.68]), average (Q5 adjusted HR, 0.53 [95% CI, 0.45–0.63]), and restful (Q5 adjusted HR, 0.50 [95% CI, 0.43–0.59]) sleep. Although the greatest differences in CVD incidence were identified using the composite healthy lifestyle index including all 5 lifestyle variables, lower incidence of CVD were identified with a lifestyle index containing any 4 of the variables. Individually, as outlined in Figure 1, lifestyle factors were also associated with lower CVD incidence including not smoking (Q5 adjusted HR, 0.41 [95% CI, 0.36–0.46]), having a healthy waist circumference (Q5 adjusted HR, 0.74 [95% CI, 0.66–0.82]), being physically activity (Q5 adjusted HR, 0.77 [95% CI, 0.69–0.85]), and eating a healthy diet (Q5 adjusted HR, 0.49 [95% CI, 0.44–0.54]). These results highlight the importance of all these healthy lifestyle factors in reducing incidence of CVD and represent important targets for patient education and patient goal setting.

Peila and colleagues' findings highlight the importance for primary care physicians to consider lifestyle factors for CVD in patient care management, even among women with a normal BMI. This importance of lifestyle risk factors among postmenopausal women often presumed to be healthy further supports individualized medicine considering a range of risk factors for CVD prevention and management. As this study evaluated a predominantly White population in a higher income country, it is important to keep in mind the racial and ethnic differences and differences across countries of residence in CVD risks and experiences and the influence of risk factors on CVD development among postmenopausal women. ⁸ , ¹⁸

The Women's Health Initiative study has some limitations. This study is composed of primarily White women, most of whom have at least some postsecondary education and are married. As body size with BMI varies between racial and ethnic groups, and racial and ethnic groups experience different rates of CVD, it is important to recognize these results may not translate as accurately to women of other racial or ethnic groups. ⁴ , ¹⁹ Similarly, women living in low‐income settings, often less educated and less likely to be married, may also experience lifestyle factors differently. ⁴ Further, the limitations of waist circumference as a lifestyle factor oversimplify the complexities of adiposity in relation to environment, biology and psychosocial factors. Additionally, the removal of alcohol intake from the healthy lifestyle index did not change the associations of CVD. The healthy lifestyle index Q5 adjusted HR for CVD was 0.48 (95% CI, 0.43–0.54) both with and without alcohol consumption, and HR for alcohol quintiles alone with CVD were each nonsignificant (range: Q2 HR, 0.86 [95% CI, 0.72–1.02] to Q3 HR, 1.01 [95% CI, 0.89–1.16]). Thus, the importance of reduced alcohol consumption in reducing risks of CVD for this population appears less important.

Expanding on this identification of important lifestyle factors, even among women without obesity, diabetes, or hypertension, is a vital next step to further our understanding of women's experience of CVD and support meaningful prevention, management, and treatment strategies for all women. Better understanding of the intersectionality of ethnic differences; experiences of colonization; socioeconomic status; built and social environments and health care access; mental well‐being; social supports; gender experiences including identity, roles, relations, and institutionalized gender; and cultural connectedness in relation to women's risks and experience of CVD is necessary to effectively improve women's health. ⁸ , ¹¹ , ²⁰

Continuing to evaluate women‐specific development, experience, and treatment of CVD is of paramount importance. Understanding these experiences among diverse women, including across the lifespan, races or ethnic groups, and body sizes, is important to improve cardiovascular outcomes for all women. Building on these recognitions of women‐specific experiences of CVD risk factors to include the layers of social, cultural, and geopolitical experiences will lead us to break the glass ceiling of women's CVD health and build a healthier world and better outcomes for all women.

Disclosures

Dr Foulds reports grants from The Canadian Institutes of Health Research, The Social Sciences and Humanities Research Council, The Heart and Stroke Foundation of Canada, and The Saskatchewan Health Research Foundation.