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“Cardiovascular health” is a new construct defined by the American Heart Association (AHA) as part of its 2020 Impact Goals definition. The applicability of this construct to community-based populations and the distributions of its components by race and sex have not been reported.
The AHA construct of “cardiovascular health” and the AHA “ideal health behaviors index” and “ideal health factors index” were evaluated among 1933 participants (mean age 59 years; 44% blacks; 66% female) in the community-based Heart Strategies Concentrating on Risk Evaluation study. One of 1933 participants (0.1%) met all 7 components of the AHA's definition of ideal cardiovascular health. Less than 10% of participants met ≥5 components of ideal cardiovascular health in all subgroups (by race, sex, age and income level). Thirty-nine subjects (2.0%) had all four components of the ideal health behaviors index and 27 (1.4%) had all three components of the ideal health factors index. Blacks had significantly fewer ideal cardiovascular health components than whites (2.0±1.2 vs. 2.6±1.4, p<0.001). After adjustment by sex, age and income level, blacks had 82% lower odds of having ≥5 components of ideal cardiovascular health (Odds Ratio 0.18, 95% Confidence Interval (CI)=0.10-0.34, p<0.001). No interaction was found between race and sex.
The prevalence of ideal cardiovascular health is extremely low in a middle-age community-based study population. Comprehensive individual and population-based interventions must be developed to support the attainment of the AHA's 2020 Impact Goals for cardiovascular health.
Despite the decline in age-standardized cardiovascular disease (CVD) and stroke mortality rates over the last four decades, CVD remains the leading cause of morbidity and mortality in the United States1. The American Heart Association (AHA) 2010 Impact Goal aimed to reduce coronary heart disease (CHD) and stroke death rates and prevalences of CVD risk factors such as smoking, hypercholesterolemia, hypertension, physical inactivity, obesity and diabetes2. Although declines in CHD and stroke mortality and decreases in the prevalences of hypercholesterolemia and uncontrolled hypertension were achieved, AHA goals for smoking cessation, increased physical activity, and decreased prevalences of obesity and diabetes have not been met1,3. In this context, the AHA 2020 Impact Goal released in January 2010 focuses on promotion of health and control of risk rather than solely on prevention and treatment of specific diseases. This new Impact Goal defines the construct of “Cardiovascular Health” and presents metrics to monitor it over time3.
The AHA defines ideal cardiovascular health as the simultaneous presence of four ideal health behaviors (nonsmoking, body mass index (BMI) <25 kg/m2, physical activity at goal level, diet consistent with current guideline recommendations) and three ideal health factors (untreated total cholesterol <200mg/dL, untreated blood pressure <120/<80 mmHg, untreated fasting glucose <100 mg/dL). The 2020 Impact Goals aim to improve cardiovascular health of all Americans by 20% and reduce CVD and stroke deaths by 20%. Furthermore, the writing committee recommended the use of the new constructs to monitor race and sex disparities and the expansion of preventive efforts towards underserved populations3.
Previous studies have described the prevalences of different combinations of health behaviors and factors and their associations with health outcomes4,5,6. However, application of the AHA construct of cardiovascular health to a diverse population has not been reported. Our study applies the AHA 2020 Impact Goals to a cohort of 1933 participants in the community-based Heart Strategies Concentrating on Risk Evaluation (Heart SCORE) study.
Heart SCORE began in 2003 as a community-based participatory research study conducted in Allegheny County, PA. Initial aims of this single site study were to improve risk stratification, identify racial disparities and evaluate mechanisms for population differences in CVD. Pre-specified recruitment goals were enrollment of 2,000 participants (50% black), including 800 participants at low Framingham risk, 1,000 participants at intermediate or high Framingham risk and 200 participants with established CVD. Minority recruitment was enriched through community-based initiatives in partnership with the Pittsburgh Theological Seminary and Urban League of Greater Pittsburgh, and mass mailings. Participants were 45-75 years old at entry; individuals with a comorbid condition that was expected to limit life expectancy to <5 years or an inability to undergo annual follow-up visits were excluded. Baseline evaluation included assessment of demographics, psychosocial characteristics and exercise and dietary habits, measurements of traditional and emerging CVD risk factors (e.g., C-reactive protein, Interleukin-6, lipoprotein particle sizes), evaluation for sleep disturbances, and assessments of subclinical atherosclerosis (using electron beam CT scan, brachial artery ultrasonography, finger pulse amplitude tonometry). Ongoing annual evaluations include measurement of risk factors, tabulation and adjudication of adverse events, and periodic assessments of subclinical atherosclerosis. The present analyses of baseline visit data were confined to the 1933 participants who self-reported race as either black or white. Sixty-seven subjects who reported other races were not included because the number of participants in these categories was too small for a meaningful analysis. The study was approved by the Institutional Review Board at the University of Pittsburgh. All subjects provided written informed consent.
Age, race, sex, education level and annual income were obtained by self-report at the baseline visit. Race was self-identified as “Black or African American”, “White”, “Asian”, “American Indian or Native Alaskan”, “Native Hawaiian or Pacific Islander”, “Other”. Education was categorized as “some college or higher” or “less than college”. Individual annual income was reported as: “Less than $10,000”, “10,000-<$20,000”, “$20,000-<$40,000”, “$40,000-<$80,000” and “$80,000 or more”. Participants self-reported a history of clinical CVD (CHD, heart failure, stroke), CVD risk factors (family history of premature CVD, cigarette smoking, hypertension, diabetes and hyperlipidemia), physical activity and diet, and use of medications for hypertension, hyperlipidemia or diabetes.
In accordance with AHA definitions3, ideal cardiovascular health was defined as the simultaneous presence of four ideal health behaviors (nonsmoking, BMI <25 kg/m2, physical activity at goal level, diet consistent with current recommendations) and three ideal health factors (untreated total cholesterol <200mg/dL, untreated blood pressure <120/<80 mm Hg and untreated fasting glucose <100 mg/dL) in the absence of clinical CVD. For each behavior and factor, prevalences of ideal, intermediate and poor health status were calculated as follows:
Four AHA-defined ideal health behaviors were measured at the baseline visit- (1) Current smoking- Participants were classified as “never”, “former” or “current” smokers from self-reported information. (2) Body mass index- BMI was calculated as weight (kilograms)÷the square of height (meters). BMI was classified as ideal (<25 kg/m2), intermediate (25-29.9 kg/m2) or poor (≥30 kg/m2). (3) Physical activity- Physical activity was evaluated using the Lipid Research Clinic Questionnaire7, which includes questions about type and frequency of physical activity at work and during leisure time and permits classification of individuals as: Very active, moderately active and inactive. Although the amount of exercise (minutes/week) could not be derived, the questionnaire provided approximations of ideal, intermediate and poor physical activity. (4) Consumption of fruits and vegetables- The PrimeScreen questionnaire8 was used to evaluate average daily consumption of fruits and vegetables. This self-administered questionnaire evaluates diet quality using average frequency of consumption of specific foods and food groups during the previous year. Although PrimeScreen is not intended to assess the total intake of specific nutrients, a cutoff value of three servings/day of fruits and vegetables has been shown to correlate closely with 5 servings/day when derived from more extensive food frequency questionnaires8. Therefore, we used PrimeScreen to classify individuals as having an ideal (≥3 servings per day) or intermediate-poor (<3 servings per day) consumption of fruits and vegetables. Discrimination between intermediate and poor nutrition status was not possible. The AHA also recommended quantification of consumption of fish, fiber-rich whole grains, sodium and sugar-sweetened beverages, but these data cannot be derived from PrimeScreen.
Three AHA-defined ideal health factors were measured at baseline- (1) Total cholesterol- measured in fasting venous blood drawn using standard laboratory techniques at the University of Pittsburgh Medical Center clinical laboratory. Total cholesterol status was defined as: ideal (<200 mg/dL, untreated), intermediate (200-239 mg/dL or treated with lipid lowering agents to goal9), and poor (≥240 mg/dL). (2) Blood pressure (BP)- measured twice after 5 minutes of rest in a seated position by experienced research nurses using a manual sphygmomanometer and an appropriately-sized cuff. The average of the two readings was used to classify BP status as: ideal (systolic blood pressure (SBP) <120mmHg and diastolic blood pressure (DBP) <80mmHg) in the absence of antihypertensive therapy, intermediate (SBP 120-139 or DBP 80-89 or individuals treated to goal10), or poor (SBP ≥140mmHg or DBP ≥90 mmHg). (3) Fasting plasma glucose (FPG)- Measured in fasting venous blood using standard analytical technique. FPG was classified as ideal (untreated FPG <100mg/dL), intermediate (FPG 100-125mg/dL or treated to goal), or poor (FPG ≥126 mg/dL).
From the individual health behaviors and factors described above, we generated corresponding AHA indices, which were then analyzed separately. The ideal health behaviors index corresponds to the number of ideal behaviors that were present at the baseline study visit (score 0-4). Subjects with a score of four were classified as having “ideal health behaviors”. The ideal health factors index corresponds to the number of health factors present at baseline plus “not smoking” (score 0-4). A score of four classified a subject as having “ideal health factors”. The inclusion of smoking as a component of both health behaviors and health factors indices was explicitly recommended by the AHA3.
Continuous variables were described by means±standard deviations and compared by t-tests or corresponding non-parametric tests based on distributional properties. Categorical variables were described by percentages and compared by chi-square tests. Subgroup analyses by race, age, sex and income level were conducted. To evaluate the independent effect of race on ideal cardiovascular health, the ideal health behaviors index and the ideal health factors index, uni- and multivariable logistic regression models were generated that sequentially added a selection of other socio-demographic predictors (sex, age, education, income level, marital status, living status and work status). An annual income level of >$40,000 for a study participant was chosen as the threshold for the multivariable analysis in correspondence with the median income in the U.S. Alternative definitions for each of the indicators of interest were examined when small numbers of subjects reached the original definition of “ideal”. All data analyses were performed using PWSA statistical package version 18.0 (SPSS, Inc., Chicago, IL), with 2-sided P-values<.05 considered to be statistically significant.
Analyses were confined to 1933 participants (97% of cohort) who self-reported race as black (44%) or white. Table 1 presents baseline characteristics. Mean age of the study population was 59±7.5 years; 74% were <65 years old and blacks were on average two years younger than whites. A majority of individuals (81%) had at least some college education and 57% had at least an associate degree. More than half reported an annual income of ≥$40,000 and one in 5 reported an annual income ≥$80,000. Income levels were significantly higher among whites and for males (data not shown).
The distribution of components of cardiovascular health in the cohort and in subgroups by race and sex are shown in Table 2. Most individuals were classified as having an intermediate or poor health status in each of the AHA-defined health behaviors and factors, except for smoking and FPG in which the ideal category was the predominant group. Less than 20% of the cohort had a BMI <25 kg/m2, <40% reported a sufficient consumption of fruits and vegetables and less than a quarter were in the ideal (i.e., very active) category for physical activity. For health factors, the ideal categories for total cholesterol, BP and FPG were reached by 25.1%, 15.1% and 63.1% of the participants, respectively.
Males had significantly worse health status with respect to smoking, BMI, BP and FPG; females had poorer physical activity and total cholesterol statuses. In comparison to males, a higher proportion of females reported an ideal consumption of fruits and vegetables, but the difference was non-significant. Blacks had a significantly poorer health status than whites in every component of cardiovascular health, except for total cholesterol.
Analysis of the presence of all 7 ideal components of cardiovascular health in this community-based CVD prevention study demonstrated that Heart SCORE study participants presented with 2.3±1.4 ideal components, with blacks exhibiting a significantly lower number of ideal components when compared to whites (2.0±1.2 vs. 2.6±1.4, respectively, p<0.001). Furthermore, only one out of the 1933 participants (0.1%) was classified as having ideal cardiovascular health (i.e., having ideal levels of all 7 healthy behaviors and factors). The vast majority of participants (80.9%) presented with three or fewer ideal health components. Additional subgroup analyses indicated that among 102 individuals (5.3%) who had ≥5 ideal health components, there was a significantly lower proportion of blacks (2% vs. 9.2%, p<0.001) and a higher, but not statistically significant, proportion of females (6.9% vs. 4.7%, p=0.074). The proportion of subjects who met ≥5 ideal health components significantly decreased with age (7.5%, 6.5% and 3.2% in the subgroups of 45-55, 55-65 and 65-75 years of age, respectively, p=0.02) and with lower income (10%, 5.3%, 5.2% and 4.1% with annual incomes ≥$80,000, $40,000-$80,000, $20,000-$40,000 and <$20,000, respectively, p=0.008). Figure 1 depicts the distribution of participants according to the number of ideal components of cardiovascular health for the entire cohort and for subgroups by race and sex.
Thirty-nine subjects (2%) had all ideal health behaviors (smoking status, BMI, physical activity, fruits and vegetables); 211 (10.9%) had three or more. All four ideal health factors (total cholesterol level, BP, glucose level, smoking status) were present in 27 participants (1.4%); 268 (13.9%) had three or more factors. The distributions of the health behaviors and health factors indices in the entire cohort and in subgroups defined by race and sex are presented in Figures 2 and and3.3. Blacks had a significantly lower proportion of three or more ideal health behaviors compared to whites (5.2% vs. 17.7%, respectively, p<0.001). Similarly, the proportion of blacks exhibiting ≥3 ideal health factors was significantly lower than that of whites (12.3% vs. 15.9%, p=0.025). In comparison to males, females had a higher proportion of ≥3 ideal components in both indices, but the differences did not reach statistical significance (15.3% vs. 12.5%, p=0.109 for ideal health behaviors, and 13.2% vs. 10.8%, p=0.144 for ideal health factors).
“Five or more components” was used as the outcome in logistic regression models due to the small number of participants having all 7 ideal components (0.1%), or even 6 components (1.2%). In comparison to whites and after adjustment by sex, age and income level, blacks had 82% lower odds of having ≥5 components of ideal cardiovascular health (Odds Ratio 0.18, 95% Confidence Interval=0.10-0.34, p<0.001). This model explained 10.2% of the total variation in cardiovascular health. No interaction was found between race and sex in relation to cardiovascular health (data not shown). Education level, marital status, living status and work status were also explored, but no associations were found with ideal cardiovascular health or indices of ideal health behaviors and factors.
The AHA Impact Goal for 2010-2020 that was released in January 2010 focuses on promotion of health and control of risk rather than on the treatment of specific cardiovascular diseases. This goal includes a new construct of cardiovascular health and presents metrics to monitor it over time3. To the best of our knowledge, our study is the first to report the application of this construct to a cohort of participants in a community-based cardiovascular prevention study. We identified an extremely low prevalence of ideal cardiovascular health in a cohort that is composed of black and white individuals who are relatively free of overt CVD and who volunteered to participate in a cardiovascular prevention study. Even after using a less strict definition of ideal cardiovascular health (≥5 ideal health components instead of 7), less than 10% of the participants met the AHA's goal in all age groups between 45-75 years, in both black and whites, males and females, and across all subgroups of education and annual income.
Our findings add to previous reports that have demonstrated low prevalences of healthy lifestyles and health factors, both individually and in combination, in the general population and in ongoing epidemiologic studies. Reeves11 reported a 3% national prevalence of a healthy indicator composed of nonsmoking, BMI 18.5-25 kg/m2, consuming ≥5 fruits and vegetables/day and regular physical activity (≥30 minutes ≥5 times per week). The age-adjusted prevalence of the four healthy lifestyles was 3.3% among whites and 1.4% in blacks. More recently, Ford12 used data from four national surveys to create an index of low risk (not currently smoking, untreated total cholesterol<200mg/dL, untreated SBP <120 mmHg and DBP <80 mmHg, BMI <25 kg/m2 and no previous diagnosis of diabetes). Ford reported that the overall prevalence of low risk was ≈8% in the general population, but much lower in the group corresponding to our Heart SCORE participants (3.5% and 0.8% in age groups of 45-64 and 65-74 years, respectively).
Due to the comprehensive nature of the new AHA construct of cardiovascular health, we anticipated a low prevalence of ideal categories. However, the fact that only one out of 1933 participants met the definition of ideal cardiovascular health and that the indices of ideal health behaviors and factors were only met by 2.0% and 1.4% of the participants respectively, is especially concerning because of the participatory nature of our project, the use of a community-based recruitment strategy, and the inherent healthy volunteer bias that we expected to be associated with more favorable findings. One potential explanation for our finding is the age range of Heart SCORE participants (45-75 years) because, with the exception of smoking, prevalences of healthy behaviors and factors are known to decrease with aging1,13. However, several longitudinal studies have previously demonstrated that it is feasible for middle and older age subjects to maintain or even adopt a healthy lifestyle pattern and that this is associated with substantial CVD, stroke and all-cause mortality benefits6, 14-17.
The national overweight and obesity epidemic may provide another explanation for our findings. Any definition of “health” that includes a BMI of <25 kg/m2 will be unmet by a large percentage of Americans, especially blacks and other minorities18. In our study, 80.6% of the participants were classified as being overweight or obese. Furthermore, it is well recognized that other risk behaviors and factors such as poor nutrition, lack of exercise, elevated blood pressure and hyperglycemia tend to cluster with obesity. Therefore, a better understanding of the causes of overweight and obesity along with the successful implementation of programs targeting its prevention and treatment will likely increase the prevalence of ideal cardiovascular health. As an example, the efficacy of diet and physical activity counseling in class III (BMI >35 kg/m2) and class IV (BMI >40 kg/m2) obesity demonstrated by Goodpasture19 suggests that even for severely obese adults, lifestyle interventions may be associated with improvements in several components of cardiovascular health.
According to the model of determinants of health proposed by Healthy People 2010, population health can be influenced by both individual factors and an array of other critical determinants, such as physical and social environments, public health policies and interventions, and access to and affordability of health care, all of which continuously interact with each other and with individuals20. Therefore, potential approaches to increasing attainment of AHA goals in the general population include: (1) Individual level: Evolving research on the identification of individual predictors of success or failure of compliance with and the effectiveness of preventive interventions are expected to foster the development of a more personalized approach to preventive medicine. For instance, the application of genomics, metabolomics and neuroscience research may enable the development of cardiovascular prevention strategies tailored to individuals. (2) Physical and social environment levels: Although it is well accepted that strategies that improve the provision of clean and safe places for people to work, exercise and play can promote good health, and that the social environment has a profound effect on health20, there is an increasing recognition that health sciences and social sciences have been isolated within disciplinary silos. This led the National Institutes of Health to develop large-scale infrastructure programs that support interdisciplinary translational research integrating the biomedical, social, behavioral and psychological sciences21. Team-based research addressing the effects of the built environment and social interventions on CVD holds promise for improving the attainment of AHA' s goals. (3) Policies and interventions level: The National Prevention, Health Promotion, and Public Health Council was recently established with the purpose of developing a national strategy to improve health promotion and disease prevention, with an emphasis on lifestyle behavior modification and prevention measures for the five leading causes of death in the U.S. The council will also coordinate and provide leadership at the federal level22. The national strategy, which is scheduled to be released by March 2011, will hopefully be designed to promote significant and sustained improvements in health and disease prevention, including CVD. (4) Access to quality health care level: The Affordable Care Act enacted in March 2010 will guarantee access to health care for all Americans and stimulate effective integration of care provided by physicians and other health care professionals to improve outcomes, care productivity, and patient experiences23. The proactive management of preventive care and the establishment of accountable care organizations and patient-centered medical homes are expected to improve the quality and lower the cost of care. Implementation of this legislation should increase access to and promote the provision of primary care, which is expected to improve the cardiovascular health status among the general population.
The 2020 AHA Impact Goal emphasizes the need for improvement of cardiovascular health of all Americans. Our results indicate that there is a significant race-related difference in attaining ideal cardiovascular health and its components. This finding is consistent with previous reports of blacks having a disproportionately greater burden of cardiovascular risk factors and higher CVD and stroke mortality rates compared to whites1, 6, 12, 24, 25. We found that the effect of race on cardiovascular health indicators persisted after adjustment for a variety of relevant socio-demographic characteristics, including socioeconomic status. This observation is consistent with prior reports and reinforces the call for new research study designs that will increase the understanding of the underlying determinants of such disparities24, 26. These study designs may benefit from a mixed methods approach because racial disparities are related to a combination of known (e.g., genetic, psychosocial, cultural, historical) and other unrecognized factors27.
This is the first known report of the application of the new AHA definition of cardiovascular health to a community-based study cohort. The large gaps between the prevalence of ideal cardiovascular health and the AHA's goals were consistently identified in all subgroups evaluated and the significant effect of race on cardiovascular health was independent of sex, robust across different age groups, and persisted after adjustment for socioeconomic status. However, this study has several limitations. First, our population was subject to referral and healthy volunteer biases, which may explain the low prevalence of smoking and an overall high level of education. We did not find differences in cardiovascular health by education level, which should be interpreted in the context of this highly educated population, whose homogeneity in terms of years of education may limit comparisons. Although this may affect the generalizability of our findings, it does not explain the unexpectedly low prevalences of healthy behaviors and factors. Indeed, the prevalences of healthy behaviors and factors may actually be significantly lower in a more general population with lower levels of education. Second, all blood pressure measurements were obtained at a single examination visit, which may be associated with misclassification of blood pressure status as a result of the regression to the mean phenomenon28. However, even if this resulted in inflated prevalences of the intermediate and poor blood pressure categories in our cohort, a misclassification would not explain the large gap between observed blood pressures and the AHA's blood pressure goal. Additionally, if regression dilution bias is affecting our statistical models, the true effect of race on cardiovascular health is expected to be stronger than that which is reported in this study.
Third, misclassification of nutritional and physical activities may have occurred because the PrimeScreen and the Lipid Research Clinic questionnaires were not designed to evaluate the total amount of nutrients and physical activity, respectively. Therefore, we used approximations of the recommended consumption of fruits and vegetables, as well as the level of physical activity. However, our systematic approach to classification of diet and physical activity should not affect comparisons of health behaviors and factors by race and other relevant socio-demographic variables. Additionally, although other nutritional components recommended by the AHA were not assessed in the current investigation, our use of fruits and vegetables consumption as a proxy of a heart healthy diet is supported by a large body of evidence that indicates that higher consumption of fruits and vegetables correlates with an array of beneficial health effects, including reduction in blood pressure, lower rates of overweight and obesity, and reduction in risks of diabetes, CHD, stroke and certain cancers29. We anticipate that future studies using the AHA definition for a healthy diet score will likely report prevalences of ideal dietary categories lower than those observed in this study.
The prevalence of the new concept of “ideal cardiovascular health” is extremely low in a middle-aged cohort that was recruited from the general community to participate in a study of CVD risk assessment. Although black race emerged as an important determinant of the lack of achievement of “ideal cardiovascular health”, both whites and blacks have a long way to goal. The large gap between the prevalence of ideal cardiovascular health and AHA's goals suggests that the attainment of the stated goals for the next decade may be much more challenging than originally conceived. Targeted efforts will be required at multiple levels (e.g. individual, social, environmental, policies and intervention, and access to quality health care) in order to insure the achievement of these goals.
The AHA's 2020 Impact Goal focuses on promotion of health and control of risk rather than solely on prevention and treatment of specific cardiovascular diseases. This goal includes a new construct of cardiovascular health composed by seven behaviors and factors. Our study is the first report of the application of this construct to a cohort of black and white participants in a community-based cardiovascular prevention study. Only one out 1933 participants met all 7 components of the AHA's definition of ideal cardiovascular health. The indices of ideal health behaviors and ideal health factors were only met by 2.0% and 1.4% of participants, respectively. The large gap between the prevalence of ideal cardiovascular health and the AHA's goals was consistently identified in all subgroups evaluated by age, race, sex, education and income level. Although black race emerged as an important independent determinant of the lack of achievement of “ideal cardiovascular health”, both whites and blacks have a long way to goal. Our findings suggest that the attainment of the stated goals for the next decade may be more challenging than originally conceived. Practicing clinicians and their health care teams need to engage in coordinated efforts along with social sciences professionals, policymakers, and individuals and their communities in order to insure the achievement of these goals.
The authors thank Amy Beto, Mary Catherine Coast, Jowanda Green and Lee Ann McDowell for their ongoing support for Heart SCORE.
Funding Sources: This study was funded by the Pennsylvania Department of Health (ME-02-384). The department specifically disclaims responsibility for any analyses, interpretations or conclusions. Additional funding was provided by National Institutes of Health grant R01HL089292.
Disclosures: The authors have no conflicts of interest.