County-Level Social Vulnerability is Associated With In-Hospital Death and Major Adverse Cardiovascular Events in Patients Hospitalized With COVID-19: An Analysis of the American Heart Association COVID-19 Cardiovascular Disease Registry

Influence of social vulnerability index on Medicare beneficiaries' expenditures upon discharge

Medicare beneficiaries' healthcare spending varies across geographical regions, influenced by availability of medical resources and institutional efficiency. We aimed to evaluate whether social vulnerability influences healthcare costs among Medicare beneficiaries. Multivariable regression analyses were conducted to determine whether the social vulnerability index (SVI), released by the Centers for Disease Control and Prevention (CDC), was associated with average submitted covered charges, total payment amounts, or total covered days upon hospital discharge among Medicare beneficiaries. We used information from discharged Medicare beneficiaries from hospitals participating in the Inpatient Prospective Payment System. Covariate adjustment included demographic information consisting of age groups, race/ethnicity, and Hierarchical Condition Category risk score. The regressions were performed with weights proportioned to the number of discharges. Average submitted covered charges significantly correlated with SVI (β = 0.50, p < 0.001) in the unadjusted model and remained significant in the covariates-adjusted model (β = 0.25, p = 0.039). The SVI was not significantly associated with the total payment amounts (β = -0.07, p = 0.238) or the total covered days (β = 0.00, p = 0.953) in the adjusted model. Regional variations in Medicare beneficiaries' healthcare spending exist and are influenced by levels of social vulnerability. Further research is warranted to fully comprehend the impact of social determinants on healthcare costs.

Social Vulnerability Index and Cardiovascular Disease Care Continuum: A Scoping Review

Background

Social vulnerability index (SVI) estimates the vulnerability of communities to disasters, encompassing 4 separate domains (socioeconomic, household composition and disability, minority status and language, and housing and transportation). The SVI has been linked with risk and outcomes of cardiovascular disease (CVD).

Objectives

This scoping review explored the literature between the SVI and CVD continuum, with a goal to identify gaps in understanding the impact of the SVI on CVD and to elucidate future research opportunities.

Methods

We systematically searched 7 databases from inception to May 19, 2023, for articles that explored the relationship between the SVI and CVD care continuum, including prevention, diagnosis and prevalence, treatment, and health outcomes. Extracted data included SVI ranking type, populations, outcomes, and quality of studies.

Results

Twelve studies evaluated the impact of SVI on the CVD continuum. Five studies explored mortality outcomes, 3 studies explored CVD risk factor prevalence, 4 studies explored CVD prevalence, 1 study explored access to health care in those with CVD, 1 study explored the use of cardiac rehabilitation services, and 1 study explored heart failure readmission rates, all of which revealed statistically significant associations with SVI. All studies included the SVI aggregate percentile ranking, while 5 studies focused on individual thematic components. We identified gaps in understanding the SVI's impact on CVD care continuum, particularly regarding CVD prevention and early detection.

Conclusions

This review provides a comprehensive understanding of the SVI's application in assessing various aspects of the CVD care continuum and highlights potential avenues for future research.

Prevalence, Predictors, and Outcomes of Type 2 NSTEMI in Hospitalized Patients With COVID-19

BACKGROUND

Data on the incidence of type 2 non-ST-segment-elevation myocardial infarction (T2MI) in hospitalized patients with COVID-19 has been limited to single-center studies. Given that certain characteristics, such as obesity and type 2 diabetes, have been associated with higher mortality in COVID-19 infections, we aimed to define the incidence of T2MI in a national cohort and identify pre-hospital patient characteristics associated with T2MI in hospitalized patients with COVID-19.

METHODS AND RESULTS

Using the national American Heart Association COVID-19 Cardiovascular Disease Quality Improvement Registry, we performed a retrospective 4:1 matched (age, sex, race, and body mass index) analysis of controls versus cases with T2MI. We performed (1) conditional multivariable logistic regression to identify predictive pre-hospital patient characteristics of T2MI for patients hospitalized with COVID-19 and (2) stratified proportional hazards regression to investigate the association of T2MI with morbidity and mortality. From January 2020 through May 2021, there were 709 (2.2%) out of 32 015 patients with T2MI. Five hundred seventy-nine cases with T2MI were matched to 2171 controls (mean age 70; 43% female). Known coronary artery disease, heart failure, chronic kidney disease, hypertension, payor source, and presenting heart rate were associated with higher odds of T2MI. Anti-hyperglycemic medication and anti-coagulation use before admission were associated with lower odds of T2MI. Those with T2MI had higher morbidity and mortality (hazard ratio, 1.40 [95% CI, 1.13-1.74]; P=0.002).

CONCLUSIONS

In hospitalized patients with COVID-19, those with a T2MI compared with those without had higher morbidity and mortality. Outpatient anti-hyperglycemic and anti-coagulation use were the only pre-admission factors associated with reduced odds of T2MI.

Respiratory Syncytial Virus Hospitalizations Associated With Social Vulnerability by Census Tract: An Opportunity for Intervention?

Background

Respiratory syncytial virus (RSV) can cause hospitalization in young children and older adults. With vaccines and monoclonal antibody prophylaxis increasingly available, identifying social factors associated with severe illnesses can guide mitigation efforts.

Methods

Using data collected by the RSV Hospitalization Surveillance Network from 2016 to 2023, we identified RSV hospitalizations in Tennessee. We linked hospitalization information (eg, patient demographic characteristics and outcome) with population-level variables (eg, social vulnerability and health care insurance coverage) from publicly available data sets using census tract of residence. Hospitalization incidence was calculated and stratified by period (2016-2020 and 2020-2023). We modeled social vulnerability effect on hospitalization incidence using Poisson regression.

Results

Among 2687 RSV hospitalizations, there were 677 (25.2%) intensive care unit admissions and 38 (1.4%) deaths. The highest RSV hospitalization incidences occurred among children aged <5 years and adults aged ≥65 years: 272.8 per 100 000 person-years (95% CI, 258.6-287.0) and 60.6 (95% CI, 56.0-65.2), respectively. Having public health insurance was associated with higher hospitalization incidence as compared with not having public insurance: 60.5 per 100 000 person-years (95% CI, 57.6-63.4) vs 14.3 (95% CI, 13.4-15.2). Higher hospitalization incidence was associated with residing in a census tract in the most socially vulnerable quartile vs the least vulnerable quartile after adjusting for age, sex, and period (incidence rate ratio, 1.4; 95% CI, 1.3-1.6).

Conclusions

RSV hospitalization was associated with living in more socially vulnerable census tracts. Population measures of social vulnerability might help guide mitigation strategies, including vaccine and monoclonal antibody promotion and provision to reduce RSV hospitalization.

Factors Associated With Diagnostic Delay in Axial Spondyloarthritis: Impact of Clinical Factors and Social Vulnerability

OBJECTIVE

Patients with axial spondyloarthritis (axSpA) often experience significant delay between symptom onset and diagnosis for reasons that are incompletely understood. We investigated associations between demographic, medical, and socioeconomic factors and axSpA diagnostic delay.

METHODS

We identified patients meeting modified New York criteria for ankylosing spondylitis (AS) or 2009 Assessment of Spondyloarthritis International Society criteria for axSpA in the Mass General Brigham health care system between December 1990 and October 2021. We determined the duration of diagnostic delay, defined as the duration of back pain symptoms reported at diagnosis, as well as disease manifestations and specialty care prior to diagnosis from the electronic health record. We obtained each patient's Social Vulnerability Index (SVI) by mapping their address to the US Centers for Disease Control SVI Atlas. We examined associations among disease manifestations, SVI, and diagnostic delay using ordinal logistic regression.

RESULTS

Among 554 patients with axSpA who had a median diagnostic delay of 3.8 years (interquartile range 1.1-10), peripheral arthritis (odds ratio [OR] 0.65, 95% confidence interval [CI] 0.45-0.93) and older age at symptom onset (OR 0.83, 95% CI 0.78-0.88 per five years) were associated with shorter delay. AS at diagnosis (OR 1.85, 95% CI 1.30-2.63), a history of uveitis prior to diagnosis (OR 2.77, 95% CI 1.73-4.52), and higher social vulnerability (defined as national SVI 80th to 99th percentiles; OR 1.99, 95% CI 1.06-3.84) were associated with longer diagnostic delay.

CONCLUSION

Older age at back pain onset and peripheral arthritis were associated with shorter delay, whereas uveitis was associated with longer diagnostic delay. Patients with higher socioeconomic vulnerability had longer diagnostic delay independent of clinical factors.

Impact of social vulnerability on comorbid COVID-19 and acute myocardial infarction mortality in the United States

The trajectory of several cardiovascular diseases (CVD), including acute myocardial infarction (AMI), has been adversely impacted by COVID-19, resulting in a worse prognosis. The Social Vulnerability Index (SVI) has been found to affect certain CVD outcomes. In this cross-sectional analysis, we investigated the association between the SVI and comorbid COVID-19 and AMI mortality using the CDC databases. The SVI percentile rankings were divided into four quartiles, and age-adjusted mortality rates were compared between the lowest and highest SVI quartiles. Univariable Poisson regression was utilized to calculate risk ratios. A total of 5779 excess deaths and 1.17 excess deaths per 100,000 person-years (risk ratio 1.62) related to comorbid COVID-19 and AMI were attributable to higher social vulnerability. This pattern was consistent across the majority of US subpopulations. Our findings offer crucial epidemiological insights into the influence of the SVI and underscore the necessity for targeted therapeutic interventions.

Protective effect of vaccination on the risk of cardiovascular disease after SARS-CoV-2 infection

OBJECTIVE

This study investigated the incidence of CVDs after COVID-19.

METHODS

Data for 2,146,130 infected people were collected, including the vaccination status. COVID-19 patients were classified according to the number of the received vaccine doses: no, first, second, and ≥ third. To evaluate the short-term risk of CVDs after infection, adjusted odds ratios (aOR) and 95% confidence intervals (CIs) were calculated by multivariable logistic regression analysis after adjustments for covariates.

RESULTS

Compared to non-infected people, aORs [95% CIs; p value] for CVDs within a month after infection were 2.80 [2.64-2.97; < 0.001] in overall infected people and 4.62 [4.23-5.05; < 0.001], 4.20 [3.45-5.11; < 0.001], 2.79 [2.55-3.05; < 0.001], and 2.07 [1.91-2.24; < 0.001] in those who were infected after receiving no, first, second, and ≥ third vaccine doses, respectively. Among participants who received second doses of vaccine prior to contracting COVID-19, the aOR in those vaccinated with only the mRNA-based vaccine (BNT162b2 and mRNA-1273; Reference) was lower than those vaccinated with the virus-derived vaccine (ChAdOx1 nCov-19 and AD26.COV2-S; aOR 1.25 [1.06-1.48; < 0.01]).

CONCLUSION

Although COVID-19 increased the CVD risk, the inverse association in the risk of CVDs according to vaccine doses was significant in a dose-response manner. Our findings suggest that ≥ second doses of the COVID-19 vaccine prevent the risk of CVDs after SARS-CoV-2 infection.

COVID-19 Mortality Disparities Among Socially Vulnerable Medicare Beneficiaries Associated With the Quality of Nurse Work Environments in U.S. Hospitals

COVID-19 mortality disparities for socially vulnerable patients, including individuals facing higher levels of poverty, housing insecurity, and limited transportation, have been linked to the quality of hospitals where they received care. Few studies have examined the specific aspects of hospitals, such as nursing care quality, that may underlie disparate outcomes. Recent studies suggest that nursing resources in the pre-pandemic period were associated with mortality during the COVID-19 public health emergency. In this study, we examined the association between social vulnerability, the nurse work environment, and inpatient mortality among Medicare beneficiaries hospitalized with COVID-19. A cross-sectional analysis was conducted of linked survey data collected from nurses working in New York and Illinois, Medicare claims, American Hospital Association Annual Survey data, and the Social Vulnerability Index (SVI). Higher mortality rates were observed among patients in the highest quartile of social vulnerability compared to the lowest (6870 [25.8%] vs 5019 [19.1%]; P < .001). Using multivariable regression modeling, a statistically significant interaction was found between the highest SVI quartile and the nurse work environment (OR, 0.86; 95% CI, 0.76-0.98; P < .05), implying that the effect of a higher quality nurse work environment on mortality was decidedly greater for patients in the highest quartile (odds ratio = 0.86 × 0.94 = 0.80) compared to patients in the lowest quartile (OR, 0.94). Post-hoc analyses demonstrated that hundreds of COVID-19 related deaths among the most socially vulnerable patients may have been avoided if all hospitals had a high-quality nurse work environment. Strengthening the quality of nurse work environments may help to reduce health disparities and should be considered in public health emergency planning, specifically in hospitals serving socially vulnerable communities.

Collaborating for COVID-19: Hospital Health Information Exchange and Public Health Partnership

Background: The coronavirus disease (COVID-19) pandemic highlighted the need for effective communication and information sharing among health care organizations and public health systems (PHSs). Health information exchange (HIE) plays a vital role in improving quality control and efficiency in hospital settings, particularly in underserved areas. Objective: This study aimed to investigate the variation of HIE availability among hospitals based on their collaboration with the PHS and affiliation with Accountable Care Organizations (ACOs) in 2020, as well as variation by community social determinants of health. Methods: The primary data set used for this study comprised the linked data set of the 2020 American Hospital Association (AHA) Annual Survey and the AHA Information Technology Supplement. The measures used included the hospital's participation in HIE networks, availability of data exchange, and HIE measures during the COVID-19 pandemic, including whether hospitals effectively received electronically transmitted information from outside providers for COVID-19 treatment. Results: The sample size of hospitals ranged from 1,316 to 1,436, depending on different outcomes related to HIE questions. Of the hospitals surveyed, ∼67% reported public health collaboration and ACO affiliation, while 7% reported neither. Hospitals without public health collaboration or ACO affiliation were more likely to be located in underserved areas. Compared with hospitals without public health collaboration or ACO affiliation, hospitals with both were 9% more likely to report the availability of electronically transmitted clinical information from outside providers and to participate in local and national HIE networks. Furthermore, these hospitals were 30% (marginal effect [ME] = 0.30, p < 0.001) more likely to report effective receipt of information from outside providers for COVID-19 treatment and 12% (ME = 0.12, p = 0.02) more likely to always/often receive clinical information for COVID-19 treatment electronically. Conclusions: Hospital collaboration with the PHS and ACO affiliation are associated with greater availability of electronic health data, particularly during the COVID-19 pandemic.

Mapping the Heartbeat of America with ChatGPT-4: Unpacking the Interplay of Social Vulnerability, Digital Literacy, and Cardiovascular Mortality in County Residency Choices

Cardiovascular disease remains a leading cause of morbidity and mortality in the United States (US). Although high-quality data are accessible in the US for cardiovascular research, digital literacy (DL) has not been explored as a potential factor influencing cardiovascular mortality, although the Social Vulnerability Index (SVI) has been used previously as a variable in predictive modeling. Utilizing a large language model, ChatGPT4, we investigated the variability in CVD-specific mortality that could be explained by DL and SVI using regression modeling. We fitted two models to calculate the crude and adjusted CVD mortality rates. Mortality data using ICD-10 codes were retrieved from CDC WONDER, and the geographic level data was retrieved from the US Department of Agriculture. Both datasets were merged using the Federal Information Processing Standards code. The initial exploration involved data from 1999 through 2020 (n = 65,791; 99.98% complete for all US Counties) for crude cardiovascular mortality (CCM). Age-adjusted cardiovascular mortality (ACM) had data for 2020 (n = 3118 rows; 99% complete for all US Counties), with the inclusion of SVI and DL in the model (a composite of literacy and internet access). By leveraging on the advanced capabilities of ChatGPT4 and linear regression, we successfully highlighted the importance of incorporating the SVI and DL in predicting adjusted cardiovascular mortality. Our findings imply that just incorporating internet availability in the regression model may not be sufficient without incorporating significant variables, such as DL and SVI, to predict ACM. Further, our approach could enable future researchers to consider DL and SVI as key variables to study other health outcomes of public-health importance, which could inform future clinical practices and policies.

Major cardiovascular events after COVID-19, event rates post-vaccination, antiviral or anti-inflammatory therapy, and temporal trends: Rationale and methodology of the CORONA-VTE-Network study

BACKGROUND

Coronavirus disease 2019 (COVID-19) is associated with excess risk of cardiovascular and thrombotic events in the early post-infection period and during convalescence. Despite the progress in our understanding of cardiovascular complications, uncertainty persists with respect to more recent event rates, temporal trends, association between vaccination status and outcomes, and findings within vulnerable subgroups such as older adults (aged 65 years or older), or those undergoing hemodialysis. Sex-informed findings, including results among pregnant and breastfeeding women, as well as adjusted comparisons between male and female adults are similarly understudied.

METHODS

Adult patients, aged ≥18 years, with polymerase chain reaction-confirmed COVID-19 who received inpatient or outpatient care at the participating centers of the registry are eligible for inclusion. A total of 10,000 patients have been included in this multicenter study, with Brigham and Women's Hospital (Boston, MA) serving as the coordinating center. Other sites include Beth Israel Deaconess Medical Center, Anne Arundel Medical Center, University of Virginia Medical Center, University of Colorado Health System, and Thomas Jefferson University Health System. Data elements will be ascertained manually for accuracy. The two main outcomes are 1) a composite of venous or arterial thrombotic events, and 2) a composite of major cardiovascular events, defined as venous or arterial thrombosis, myocarditis or heart failure with inpatient treatment, new atrial fibrillation/flutter, or cardiovascular death. Clinical outcomes are adjudicated by independent physicians. Vaccination status and time of inclusion in the study will be ascertained for subgroup-specific analyses. Outcomes are pre-specified to be reported separately for hospitalized patients versus those who were initially receiving outpatient care. Outcomes will be reported at 30-day and 90-day follow-up. Data cleaning at the sites and the data coordinating center and outcomes adjudication process are in-progress.

CONCLUSIONS

The CORONA-VTE-Network study will share contemporary information related to rates of cardiovascular and thrombotic events in patients with COVID-19 overall, as well as within key subgroups, including by time of inclusion, vaccination status, patients undergoing hemodialysis, the elderly, and sex-informed analyses such as comparison of women and men, or among pregnant and breastfeeding women.

Race-Based Differences in ST-Segment-Elevation Myocardial Infarction Process Metrics and Mortality From 2015 Through 2021: An Analysis of 178 062 Patients From the American Heart Association Get With The Guidelines-Coronary Artery Disease Registry

BACKGROUND

Systems of care have been developed across the United States to standardize care processes and improve outcomes in patients with ST-segment-elevation myocardial infarction (STEMI). The effect of contemporary STEMI systems of care on racial and ethnic disparities in achievement of time-to-treatment goals and mortality in STEMI is uncertain.

METHODS

We analyzed 178 062 patients with STEMI (52 293 women and 125 769 men) enrolled in the American Heart Association Get With The Guidelines-Coronary Artery Disease registry between January 1, 2015, and December 31, 2021. Patients were stratified into and outcomes compared among 3 racial and ethnic groups: non-Hispanic White, Hispanic White, and Black. The primary outcomes were the proportions of patients achieving the following STEMI process metrics: prehospital ECG obtained by emergency medical services; hospital arrival to ECG obtained within 10 minutes for patients not transported by emergency medical services; arrival-to-percutaneous coronary intervention time within 90 minutes; and first medical contact-to-device time within 90 minutes. A secondary outcome was in-hospital mortality. Analyses were performed separately in women and men, and all outcomes were adjusted for age, comorbidities, acuity of presentation, insurance status, and socioeconomic status measured by social vulnerability index based on patients' county of residence.

RESULTS

Compared with non-Hispanic White patients with STEMI, Hispanic White patients and Black patients had lower odds of receiving a prehospital ECG and achieving targets for door-to-ECG, door-to-device, and first medical contact-to-device times. These racial disparities in treatment goals were observed in both women and men, and persisted in most cases after multivariable adjustment. Compared with non-Hispanic White women, Hispanic White women had higher adjusted in-hospital mortality (odds ratio, 1.39 [95% CI, 1.12-1.72]), whereas Black women did not (odds ratio, 0.88 [95% CI, 0.74-1.03]). Compared with non-Hispanic White men, adjusted in-hospital mortality was similar in Hispanic White men (odds ratio, 0.99 [95% CI, 0.82-1.18]) and Black men (odds ratio, 0.96 [95% CI, 0.85-1.09]).

CONCLUSIONS

Race- or ethnicity-based disparities persist in STEMI process metrics in both women and men, and mortality differences are observed in Hispanic White compared with non-Hispanic White women. Further research is essential to evolve systems of care to mitigate racial differences in STEMI outcomes.

Major adverse cardiovascular events are associated with necroptosis during severe COVID-19

BACKGROUND

The mechanisms used by SARS-CoV-2 to induce major adverse cardiac events (MACE) are unknown. Thus, we aimed to determine if SARS-CoV-2 can induce necrotic cell death to promote MACE in patients with severe COVID-19.

METHODS

This observational prospective cohort study includes experiments with hamsters and human samples from patients with severe COVID-19. Cytokines and serum biomarkers were analysed in human serum. Cardiac transcriptome analyses were performed in hamsters' hearts.

RESULTS

From a cohort of 70 patients, MACE was documented in 26% (18/70). Those who developed MACE had higher Log copies/mL of SARS-CoV-2, troponin-I, and pro-BNP in serum. Also, the elevation of IP-10 and a major decrease in levels of IL-17ɑ, IL-6, and IL-1rɑ were observed. No differences were found in the ability of serum antibodies to neutralise viral spike proteins in pseudoviruses from variants of concern. In hamster models, we found a stark increase in viral titters in the hearts 4 days post-infection. The cardiac transcriptome evaluation resulted in the differential expression of ~ 9% of the total transcripts. Analysis of transcriptional changes in the effectors of necroptosis (mixed lineage kinase domain-like, MLKL) and pyroptosis (gasdermin D) showed necroptosis, but not pyroptosis, to be elevated. An active form of MLKL (phosphorylated MLKL, pMLKL) was elevated in hamster hearts and, most importantly, in the serum of MACE patients.

CONCLUSION

SARS-CoV-2 identification in the systemic circulation is associated with MACE and necroptosis activity. The increased pMLKL and Troponin-I indicated the occurrence of necroptosis in the heart and suggested necroptosis effectors could serve as biomarkers and/or therapeutic targets. Trial registration Not applicable.

Necroptosis Drives Major Adverse Cardiovascular Events During Severe COVID-19

Background The mechanisms used by SARS-CoV-2 to induce major adverse cardiac events (MACE) are unknown. Thus, we aimed to determine if SARS-CoV-2 can infect the heart to kill cardiomyocytes and induce MACE in patients with severe COVID-19. Methods This observational prospective cohort study includes experiments with hamsters and human samples from patients with severe COVID-19. Cytokines and serum biomarkers were analyzed in human serum. Cardiac transcriptome analyses were performed in hamsters' hearts. Results From a cohort of 70 patients, MACE was documented in 26% (18/70). Those who developed MACE had higher Log copies/mL of SARS-CoV-2, troponin-I, and pro-BNP in serum. Also, the elevation of IP-10 and a major decrease in levels of IL-17ɑ, IL-6, and IL-1rɑ were observed. No differences were found in the ability of serum antibodies to neutralize viral spike proteins in pseudoviruses from variants of concern. In hamster models, we found a stark increase in viral titers in the hearts 4 days post-infection. The cardiac transcriptome evaluation resulted in the differential expression of ~ 9% of the total transcripts. Analysis of transcriptional changes of the effectors of necroptosis (mixed lineage kinase domain-like, MLKL) and pyroptosis (gasdermin D) showed necroptosis, but not pyroptosis, to be elevated. Active form of MLKL (phosphorylated MLKL, pMLKL) was elevated in hamster hearts and, most importantly, in the serum of MACE patients. Conclusion SARS-CoV-2 can reach the heart during severe COVID-19 and induce necroptosis in the heart of patients with MACE. Thus, pMLKL could be used as a biomarker of cardiac damage and a therapeutic target. Trial registration: Not applicable.

Moderating Effects of Racial Segregation on the Associations of Cardiovascular Outcomes with Walkability in Chicago Metropolitan Area

Cardiovascular diseases (CVDs), as the leading cause of death in the U.S., pose a disproportionate burden to racial/ethnic minorities. Walkability, as a key concept of the built environment, reflecting walking and physical activity, is associated with health behaviors that help to reduce CVDs risk. While the unequal social variation and spatial distribution inequality of the CVDs and the role of walkability in preventing CVDs have been explored, the moderating factors through which walkability affects CVDs have not been quantitatively analyzed. In this paper, the spatial statistical techniques combined with the regression model are conducted to study the distribution of the CVDs' health outcomes and factors influencing their variation in the Chicago metropolitan area. The spatial statistical results for the CVDs' health outcomes reveal that clusters of low-value incidence are concentrated in the suburban rural areas and areas on the north side of the city, while the high-value clusters are concentrated in the west and south sides of the city and areas extending beyond the western and southern city boundaries. The regression results indicate that racial segregation reduced the positive association between health outcomes and walkability, although both racial segregation and walkability factors were positively associated with CVDs' health outcomes.