The problem of disparities in vascular health

A health disparity is defined as a particular type of health difference that is closely linked with social, political, economic, and environmental disadvantages. ¹ Health inequities are systematic differences in the health status of different population groups, which have significant social and economic costs to both individuals and societies. ² These inequities refer to differences that are unnecessary and avoidable but are also considered unfair and unjust. ² Healthy People 2030 categorizes social determinants of health (SDoH), the social conditions in which people are born, live, and work, into five domains: economic stability, education, healthcare access and quality, neighborhood and built environment, and social and community context. ³ In addition, commercial determinants of health refer to the conditions, actions, and omissions by commercial factors, including the activities as well as the environment in which commerce takes place, which can have beneficial or detrimental impacts on health. ⁴ Together, these social and commercial factors have a broad impact on health risks and outcomes throughout a person’s lifetime. Health disparities in vascular disease continue to be well documented among different racial, ethnic, sex, and socioeconomic subgroups. Recognizing and assessing these inequities and the root of SDoH is crucial for clinicians and health care systems to develop strategies to address them.

In this focused issue of Vascular Medicine, multiple investigators report their original research findings related to assessing and understanding health disparities in presentation and outcomes among patients with vascular disease. Islam and colleagues ⁵ demonstrated that desirable neighborhood social characteristics including social cohesion and activity, low violence, and improved food access are independently associated with lower arterial stiffness in Black adults. Factors such as stress and discrimination have been previously theorized to cause increased oxidative stress and chronic inflammation, leading to increased arterial stiffness and vascular aging. ⁶ This is an example of the ‘weathering’ hypothesis, which uses measures of allostatic load – the cumulative wear and tear of the body caused by repeated adaption to stressors – and postulates that Black Americans experience early health deterioration as a consequence of the cumulative impact of repeated experience with social or economic adversity, political marginalization, and high-effort coping with chronic stressors. ⁷

Understanding the higher burden of peripheral artery disease (PAD) in Black patients, Lee et al. ⁸ incorporate the prognostic value of the ankle–brachial index (ABI) and lower extremity symptoms for cardiovascular risk stratification in this population. The authors found that the highest risk for major adverse cardiovascular events and all-cause mortality were in symptomatic participants with abnormal ABIs, followed by asymptomatic participants with abnormal ABIs. Their findings highlight the need to evaluate the value of PAD screening in Black adults given their increased risk of adverse outcomes even when asymptomatic. ⁸ This higher risk of PAD-related mortality is shown in the work of Dicks et al., ⁹ where utilizing NHANES data found that Black individuals presented with more premature PAD, had a higher burden of SDoH, and those with concomitant coronary artery disease (CAD) had higher rates of age-adjusted mortality compared to their White counterparts. ⁹ Issa et al. ¹⁰ show us that PAD-related mortality has decreased over the last two decades, with a plateau over the last several years. They also identified that men, Black Americans, and those in rural counties had the highest adjusted mortality rates. ¹⁰

Hispanics have historically been underrepresented in cardiovascular studies, which is important to highlight when a study includes a representative cohort of Hispanic adults. Snyder et al. ¹¹ report data on 1265 patients with confirmed pulmonary embolism (PE) in which 37% identified as Hispanic or Latino from a single institution. At their institution, Hispanic patients were less likely to present with high-risk PE, but still experienced similar rates of inpatient mortality compared with their non-Hispanic counterparts. ¹¹

Canonico et al. ¹² present a contemporary analysis on sex differences in the implementation of guideline-directed medical therapy (GDMT) in 9810 patients with PAD from a single institution. The authors found low rates of GDMT for PAD regardless of sex and symptoms, but an even lower GDMT prescription among women, irrespective of concurrent CAD, symptomatic PAD, or revascularization. ¹² Breen et al. ¹³ tackle the use of telemedicine for management of veterans with PAD in rural areas. In this pilot study, the authors demonstrate that telemedicine is feasible to facilitate a vascular consult and was effective at shortening time to vascular evaluation and, if needed, revascularization for patients with chronic limb-threatening ischemia (CLTI). ¹³ Vossen et al. ¹⁴ describe that patient-reported improvement after lower extremity revascularization was significantly associated with a higher VQ-6-NL score (a disease-specific quality of life improvement questionnaire), and that a change in postprocedure ABI equal or greater than 0.32 was needed for patients to report improvement. ¹⁴

PAD is estimated to affect over 200 million adults globally and approximately 8 million adults in the United States. In the US, it disproportionately impacts vulnerable populations across various dimensions including low-income Americans of all races, Black, Hispanic and Native Americans, as well as those living in rural areas. Black Americans are more likely to have PAD, present with more severe disease, and have worse outcomes. ¹⁵ Even after adjusting for comorbidities, socioeconomic status, and geographic location, Black patients have a nearly twofold greater rate of major amputations. ¹⁶ The higher prevalence of PAD and worse outcomes in Black patients can only be partially explained by higher rates of hypertension, smoking, and chronic kidney disease. It has been recently understood that aside from the traditional cardiovascular risk factors, SDoH and structural racism contributes to the disparities observed between Black Americans and other groups. ¹⁵ Structural racism affects health outcomes by creating residential segregation. A disproportionate number of Black and other non-White individuals live in areas of concentrated poverty, where there is less investment by government and private sector, and fewer jobs and educational opportunities, which leads to difficulty practicing healthy behaviors. In multiple ways, this can limit access to primary and subspecialty care, lead to inadequate treatment of chronic illness, and disparities in health outcomes. ¹⁷

There is a growing body of evidence pointing to disparities in other fields of vascular health. Although abdominal aortic aneurysm (AAA) is more often seen in men, women who present with ruptured AAAs tend to fare worse than men. Women tend to rupture at smaller diameters than men, have higher mortality rates, and experience perioperative complications. ¹⁸ Lack of insurance and lower socioeconomic status have been associated with higher in-hospital mortality after AAA repair. ¹⁹ Recent studies are also showcasing disparities in venous thromboembolism, with Black Americans suffering higher PE-related mortality. ²⁰ Furthermore, one analysis on carotid endarterectomy after stroke showed lower rates of intervention in non-White patients receiving treatment at ‘minority-serving’ hospitals, suggesting system-level factors as a contributor to racial disparities. ²¹

The prominent theme throughout the scientific papers in this focused issue of Vascular Medicine, is the importance of assessing how SDoHs impact morbidity and mortality in vulnerable populations with vascular disease, developing innovative solutions to address access to quality primary and specialty care, and ensuring sustained adherence to guideline-concordant quality health care delivery. These health inequities have many implications, including economic costs, health care costs, quality of life, and number of lives. As we continue to report and understand the root cause of these disparities, focused action plans need to be developed to pave the way for health equity.