Associations Between Social Determinants of Health and Cardiovascular Health of U.S. Adult Cancer Survivors

Background Relationships between the social determinants of health (SDOH) and cardiovascular health (CVH) of cancer survivors are underexplored. Objectives This study sought to investigate associations between the SDOH and CVH of adult cancer survivors. Methods Data from the U.S. National Health Interview Survey (2013-2017) were used. Participants reporting a history of cancer were included, excluding those with only nonmelanotic skin cancer, or with missing data for any domain of SDOH or CVH. SDOH was quantified with a 6-domain, 38-item score, consistent with the Centers for Disease Control and Prevention recommendations (higher score indicated worse deprivation). CVH was quantified based on the American Heart Association’s Life’s Essential 8, but due to unavailable detailed dietary data, a 7-item CVH score was used, with a higher score indicating worse CVH. Survey-specific multivariable Poisson regression was used to test associations between SDOH quartiles and CVH. Results Altogether, 8,254 subjects were analyzed, representing a population of 10,887,989 persons. Worse SDOH was associated with worse CVH (highest vs lowest quartile: risk ratio 1.30; 95% CI: 1.25-1.35; P < 0.001), with a grossly linear relationship between SDOH and CVH scores. Subgroup analysis found significantly stronger associations in younger participants (Pinteraction = 0.026) or women (Pinteraction = 0.001) but without significant interactions with race (Pinteraction = 0.051). Higher scores in all domains of SDOH were independently associated with worse CVH (all P < 0.001). Higher SDOH scores were also independently associated with each component of the CVH score (all P < 0.05 for highest SDOH quartile). Conclusions An unfavorable SDOH profile was independently associated with worse CVH among adult cancer survivors in the United States.

R ecent advances in cancer care have led to significantly improved cancer survival rates.As a result, the population of cancer survivors is growing. 1 In 2022, there were an estimated 18.1 million cancer survivors in the United States (ie, approximately 5% of the population). 2][9][10] Therefore, cardiovascular care for these patients is increasingly important.
The increased CVD burden among cancer survivors may not be entirely attributable to traditional cardiovascular risk factors. 7[13] Therefore, it is plausible that social determinants of health (SDOH)-encompassing socioeconomic, environmental, and psychosocial factors that influence health-are also associated with CVD in cancer survivors.However, despite efforts to address SDOH-related cardiovascular health (CVH) disparities, 14 the relationship between SDOH and CVH among cancer survivors remains underexplored.This knowledge gap is particularly relevant as cancer affects both SDOH 15 and CVH, 16 meaning that associations between CVH and SDOH observed in other populations may not be directly extrapolated to cancer survivors.Hence, this study aimed to investigate the association between SDOH and CVH among cancer survivors.

METHODS
DATA SOURCE.The National Health Interview Survey (NHIS) is an annual household survey conducted by the National Center for Health Statistics/Centers for Disease Control and Prevention, collecting health data for noninstitutionalized civilian adults. 17ilizing multistage probability sampling, the NHIS generates representative estimates for the noninstitutionalized U.S. population. 17The NHIS uses sampling weights that account for the complex survey design, including stratification, clustering, and oversampling of certain population groups.These weights are calculated to ensure that the estimates derived from the survey data accurately reflect the characteristics of the noninstitutionalized U.S. population. 18Harmonized data were obtained through the Integrated Public Use Microdata Series Health Survey database. 19Because all data used were deidentified and publicly available, it was exempt from review by an Institutional Review Board.
STUDY POPULATION.We analyzed NHIS data from 2013 to 2017 because only these iterations of the NHIS contained all variables required in the ascertainment of CVH score and SDOH score (detailed subsequently).We included adults ($18 years of age) reporting a diagnosis of cancer, defined as patients who responded "yes" when asked if they had ever been told "by a doctor or other health professional that [they] had cancer or a malignancy of any kind." Those reporting a diagnosis of nonmelanoma skin cancer were excluded, consistent with other cancer survivorship studies. 20,21Those with missing data for any domain of SDOH or CVH, or any of the prespecified covariates (sex, age, race, sexual orientation, and the presence of any known cardiac condition) were also excluded.
ASCERTAINMENT OF CVH.The primary outcome was CVH, quantified by American Heart Association's Life's Essential 8 model. 22Because the NHIS does not include detailed dietary data, the score comprised 7 binary domains/risk factors (hypertension, diabetes mellitus, hypercholesterolemia, current smoking, physical activity, inappropriate sleep, and obesity).
Current smoking status was self-reported.Obesity was defined as body mass index $30 kg/m 2 .Insufficient physical activity was defined as not engaging A higher composite score indicated worse CVH.This score has been published previously. 23CERTAINMENT OF SDOH.We developed a comprehensive SDOH framework based on the 6 domains defined by the Kaiser Family Foundation: economic stability, neighborhood, community and social context, food poverty, education, and access to health care. 24Using NHIS data, we identified 38   or >7 drinks/wk (for women) in the past year. 28nally, as worse CVH might have been due to better detection by higher rates of cardiometabolic work-up, a post hoc exploratory analysis was performed to explore the association between the SDOH score (in quartiles) and a self-reported history of having had blood pressure, fasting blood glucose, and cholesterol checked within the past year.Multivariable logistic regression was used for this analysis.
All P values were 2-sided, with a P value <0.05 considered statistically significant.Because participants with missing values were excluded, the study population had no missing data.All analyses were performed using version 16.1 (StataCorp LLC).

RESULTS
Of the 16,586 subjects with known cancer in NHIS 2013-2017, 8,254 were analyzed after applying the Satti et al in Supplemental Table 2.The distribution of the CVH score is visualized in Supplemental Figure 2, with a weighted mean score of 2.9 AE 1.5.Characteristics of the included subjects are summarized in Table 1.
Characteristics of subjects were also tabulated against the included subjects in Supplemental Tables 3 and 4.
The included and excluded subjects were generally comparable, except that the included subjects were older, were more commonly male, had higher rates of hypercholesterolemia, and less commonly had low family income compared with the excluded subjects.Abbreviations as in Table 1.
mortality in the general population. 12,23,29,30Previous studies demonstrated that various domains of SDOH influence CVH in complex and variable ways.For example, Makhlouf et al 31 found that neighborhood walkability and the green space availability were associated with better CVH in the United States.
Similarly, in another cross-sectional survey, food insecurity was associated with suboptimal CVH. 32using insecurity has also been identified to be associated with CVH in the general population. 33though all these SDOH domains are important, only specific facets of SDOH have been investigated for their relationships with CVH in cancer survivors.For instance, Batra et al 34 found that rural residence, low income, and low education were associated with higher risks of developing CVD in cancer survivors.These were confirmed by Berkman et al, 35 who found that an annual household income <$50,000 USD was associated with increased odds of CVD in young adult cancer survivors, and Appiah et al, 36 who showed that breast and gynecologic cancer survivors residing in rural areas had higher risks of cardiovascular mortality.
However, the impact of SDOH extends beyond these few specific factors, and studying individual domains of SDOH in isolation is inadequate because they are likely associated with CVH in complex and intersectional ways.Instead, an aggregate SDOH risk score may better identify and improve care for socially disadvantaged individuals. 37Hence, we used a well-established and published aggregate SDOH score, ensuring reliability, robustness, and objectivity.Similar issues may exist for CVH quantification, which is evolving.Therefore, we referenced the American Heart Association's Life's Essential 8 model, which is an evidence-based framework created in 2022 to define and quantify CVH. 22though the original model involved more detailed measurements and included diet, the CVH score used in this study had been previously published and shown to be a robust measurement of CVH. 23,25The use of this CVH score thus ensured robustness of our findings.This was further reinforced by sensitivity analyses, in one of which excessive alcohol use was added to the CVH score in recognition of CVH as an evolving concept.
Importantly, we found that the association between SDOH and CVH was particularly strong among women or young individuals, congruent with previous research on associations between social vulnerability and mortality due to comorbid cancer and CVD. 38The worse CVH associated with disadvantaged SDOH may have contributed to such observations for mortality, further emphasizing the need to prioritize interventions that address social and economic disadvantage in female and young cancer survivors.
UNDERLYING MECHANISMS.The association between SDOH and CVH is likely multifactorial.However, our exploratory analyses suggested that differences in rates of cardiometabolic work-up within the past year were unlikely to be the driving factor behind this association.We speculate that the adverse association between socioeconomic disadvantage and mental health may be one of the potential mediators. 39,40We previously showed that psychological distress is associated with worse CVH in adult cancer survivors. 41Others have also hypothesized that psychological factors mediate associations between social/physical environments and CVD, 42,43 which may be positive (eg, social support improving health behaviors among racial/ethnic minority groups by reducing depressive symptoms) 44,45 or negative (eg, poorly built environments increasing the risk of CVD via an increased likelihood of mental disorders causing chronic life stress).However, our study is not devoid of limitations. First in $75 min/wk of vigorous exercise, $150 min/wk of moderate intensity exercise or combination, or a total combination of $150 min/wk of moderate intensity/ vigorous exercise.Inappropriate sleep duration was defined as <6 hours or >10 hours of sleep on average per night.Each of the 7 CVH domains was coded as 0 (absence of a risk factor) or 1 (presence of a risk factor), with a maximum composite CVH score of 7. A B B R E V I A T I O N S A N D A C R O N Y M S CVD = cardiovascular disease CVH = cardiovascular health NHIS = National Health Interview Survey RR = risk ratio SDOH = social determinants of health Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China; and the k School of Nursing and Health Studies, Hong Kong Metropolitan University, Hong Kong SAR.*Drs Satti and Chan contributed equally to this work as joint first authors.The authors attest they are in compliance with human studies committees and animal welfare regulations of the authors' institutions and Food and Drug Administration guidelines, including patient consent where appropriate.For more information, visit the Author Center.Manuscript received April 23, 2023; revised manuscript received July 21, 2023, accepted July 24, 2023.

2 0 2 4 : 4 3 9 -4 5 0
Figure 1, with a weighted mean score of 5.3 AE 4.2.Subjects in the first quartile of the SDOH score had a score of 0 to 2, the second quartile had a score of 3 to 4, the third quartile had a score of 5 to 7, and the fourth quartile had a score of 8 to 28.The per component distribution of the SDOH score is detailed

FIGURE 2
FIGURE 2 Summary of Key Results may also need to be recalibrated to enhance cancer survivors' access to preventive medicine services, such as ensuring continued follow-up care for those with disadvantaged SDOH profiles.Given the interconnected nature of these factors and their cascading downstream effects on health outcomes, national efforts are needed to reduce social disparities in CVH among cancer survivors.This can be achieved within broader programs such as the Centers for Medicare and Medicaid Services initiative,48 which focuses on

FIGURE 3
FIGURE 3 Associations for the Components of CVH

TABLE 1
Demographics and Components of Cardiovascular Health in the Included Subjects Values are n or n (%).Percentages are unweighted.CVH ¼ cardiovascular health; SDOH ¼ social determinants of health.Values are adjusted risk ratio (95% CI), P value.a Adjusted for sex, age, race, sexual orientation, and the presence of any known cardiac condition.

TABLE 3
Associations Between Individual Domains of the SDOH Score and CVH Adjusted for sex, age, race, sexual orientation, and the presence of any known cardiac condition.
a b Data distribution did not allow meaningful quartiles to be generated.
CONCLUSIONSAmong cancer survivors in the United States, an unfavorable SDOH profile was independently associated with worse CVH, especially in young and female subjects.This highlights the need for a comprehensive approach to health care for cancer survivors that considers the broader socioeconomic and environmental factors associated with their CVH.FUNDING SUPPORT AND AUTHOR DISCLOSURESThis work was partly supported by the Tianjin Key Medical Discipline (Specialty) Construction Project (Project number: TJYXZDXK-029A) and by a grant from the Hong Kong Metropolitan University (Project Reference No. RIF/2022/2.2).The funder played no role in any part of this study.Dr Dee is funded in part through the Cancer Center Support Grant from the National Cancer Institute (P30 CA008748).Dr Sharma is supported by the Blumenthal Scholarship in Preventive Cardiology at the Ciccarone Center for the Prevention of Cardiovascular Disease at Johns Hopkins University School of Medicine and American Heart Association grant 979462.Dr Virani has received grant support from the Department of Veterans Affairs, the World Heart Federation, and the Tahir and Jooma Family; and honoraria from the American College of Cardiology (Associate Editor for Innovations).Dr Shapiro has served on scientific advisory boards for Amgen, Ionis, Novartis, and Precision BioScience; and as a consultant for Ionis, Novartis, Regeneron, EmendoBio, and Aidoc.All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.