One by One, Social Determinants of Health Add to Fatal CHD Risk
Counting the risk factors may help guide practice, researchers say. But real change requires a shift in values and public policy.
The more social determinants of health (SDH) a person has, the higher their risk of dying from coronary heart disease (CHD) over the next decade, observational data on more than 22,000 people confirm.
Additive burdens posed by race or social isolation, poverty, economic instability, poor access to healthcare, and lower education translate into real-world consequences, Monika M. Safford, MD (Weill Cornell Medicine, New York, NY), and colleagues report in Circulation. This risk persists even when accounting for more-traditional markers like comorbidities and smoking.
“Counting the number of SDH may be a promising approach that could be incorporated into clinical care to identify individuals at high risk of CHD,” the researchers suggest. While more-formal “indices reflecting social deprivation have been developed for population management,” they say, these tools can be unwieldy during an office visit.
Khadijah Breathett, MD (University of Arizona, Tucson), commenting on the results for TCTMD, said, “This is yet another study to show that social determinants of health matter maybe even more so than traditional risk factors when we’re talking about risk of fatal cardiovascular disease.”
It’s a reminder, Breathett continued, that it’s time to start addressing this problem. “We need to use public policy to specifically address each of these factors. We need to reallocate resources from our cities, from our healthcare systems, from our GDP to manage these different social determinants of health if we’re really going to change the trajectory of cardiovascular disease in this nation.”
For years, these disparities have been present and are even growing, she stressed. What’s more, COVID-19—known to more harshly affect minority groups, such as Black and Hispanic people—may impart long-term effects that carry more weight for some than for others based on sociodemographic factors.
“We have to decide,” urged Breathett, “if we’re going to change the course of history or continue to proceed in a way where one population continues to suffer and have worse outcomes than another.”
For their analysis, Safford et al turned to the prospective longitudinal Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort study, which enrolled community-dwelling Black and white adults over the age of 45 between 2003 and 2007. Within this group, 22,152 participants (58.8% women; 42.0% Black) were free of CHD at baseline.
The researchers derived their seven SDH from the US government’s Healthy People 2020 framework, arriving at these risk factors: Black race, social isolation, education less than high school degree, annual household income < $35,000, living in a zip code where > 25% of residents are below the federal poverty line, lack of health insurance, and residing in one of the nine US states with the least public health infrastructure.
Among the patients without baseline CHD, 20.6% had no SDH, 30.6% had one, 23.0% had two, and 25.8% had three or more.
Median follow-up was 10.7 years, during which time 463 fatal incident CHD events and 932 nonfatal MIs occurred.
For fatal CHD, age-adjusted incidence per 1,000 person-years increased from 1.30 among those with none of the risk factors to 2.86 among those with more than three SHD. For nonfatal MI, it rose from 3.91 with no SDH to 5.44 with two or more risk factors.
Adjusted for age, gender, comorbidities, smoking, and alcohol use, as well as other traditional risk factors, incident CHD risk remained significantly higher with more than three SDH (HR 1.67; 95% CI 1.18-2.37). Nonfatal MI lost statistical significance when these covariates were accounted for, however (HR 1.14; 95% CI 0.93-1.41).
“The variables used here could be widely implemented as part of the social history, alerting treating physicians to intensify aggressiveness of CHD risk factor management, since the majority of out-of-hospital cardiac arrests are related to structural CHD,” the authors say, adding, “Population health managers could use the simple count of SDH to identify patients for intervention to improve linkages to community resources including housing, social support, availability of healthy foods, or transportation.”
Emerging From a 'Painful Year’
Just this spring, the American Heart Association issued an advisory calling out structural racism, with ideas on how to dismantle it.
Breathett expressed hope, too, that change may come from the racial/ethnic disparities witnessed in COVID-19 and the reckoning over racism in the United States. “We have to look at what positivity can come from such a painful year in our country and in the world. One highlight has been a focus on social determinants of health, on systemic racism, on bias.
“I think it’s because of people being glued to the news and aware of the levels of police brutality that are happening—that have been happening for years—but they’re more aware . . . and they agree it does not make sense,” she said. Thanks to growing public support and younger generations that increasingly embrace diversity, “we are not going to continue to stand for these levels of inequality.”
What with the incoming Biden administration, Breathett predicted “these issues are going to remain a prominent focus.” The key will be hard work, she added, in the form of “continued changes in our structures, systems, and culture” as well as a recognition of shared humanity. It’s true that “a lot of people don’t like change,” said Breathett. “But I think this past year has shown what can happen if we don’t change.”
For clinicians, one step forward would be if the Centers for Medicare & Medicaid Services created an ICD-10 code for SDH, as they have for homelessness, she suggested. “What if we started including those? And what if we started reimbursing the healthcare systems that are taking care of these patient populations? What if we reimburse them even further if they reduce these social determinants of health for these patients?”
Safford MM, Reshetnyak E, Sterling MR, et al. Number of social determinants of health and fatal and nonfatal incident coronary heart disease in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. Circulation. 2020;Epub ahead of print.
- The study is supported by the National Institutes of Health (NIH).
- Safford reports receiving research grant funding from Amgen.
- Breathett reports receiving NIH grants.