Array of Public Interventions Help Reduce US Health Disparities

Health disparities in the United States persist, and may even be increasing, despite improvements in medical care and disease prevention. Social determinants—poverty, lack of access to quality education or work, unhealthy housing, and neighborhood violence—are increasingly being recognized as factors that affect health and contribute to disparities through negative neurodevelopmental and biological consequences beginning in childhood that accumulate and produce disease.

Rachel L.J. Thornton, PhD, of the Johns Hopkins School of Medicine, and colleagues wrote in Health Affairs that their analysis of interventions focusing on social determinants of health shows that population health can be improved and social disparities reduced. The interventions they use in their study targeted education and early childhood; urban planning and community development; housing; income enhancements and supplements; and employment.

“Although the interventions we discuss primarily target a single social determinant, they likely have ripple effects across others,” the researchers noted.

The interventions studied in their analysis included the Perry Preschool Project in Michigan in the 1960s, which found that disadvantaged 3- and 4-year olds who received high-quality preschool education engaged in fewer risky health behaviors, such as smoking and substance use in adulthood, and also found that at age 40, those who had received the preschool intervention had higher education, income, and health insurance coverage and lower rates of violent crime, incarceration, welfare receipt, and out-of-wedlock births compared with the control group. The Great Smoky Mountains Study in North Carolina examined the impact of income supplements to Native Americans resulting from casino revenue. The supplements were associated with improved mental health outcomes in adolescents that persisted through early adulthood, increased education, and reduced criminal offenses among Native American youth. Studies of the Head Start program, however, were not as promising and showed no consistent evidence of positive health impacts.

Most current interventions do not take a life-course perspective, and tend instead to be disease specific—targeting individual and health systems factors without addressing social determinants, the researchers say. Existing research suggests that eliminating disparities in morbidity and mortality for people with less than a college education would have an estimated economic value of $1.02 trillion, and that eliminating racial and ethnic disparities would reduce medical care costs by $230 billion and indirect costs of excess morbidity and mortality by more than $1 trillion over 4 years.

“Reducing and eliminating disparities is a moral imperative that is also advantageous to the US economy,” the investigators wrote.

Their study suggests that interventions addressing “upstream” social determinants are cost-effective and lead to long-term societal savings, and can also improve population health and reduce disparities.

“The complex interplay of factors that have resulted in persistent health disparities cannot be reversed with short-term investments,” the authors noted.

Social determinant-related interventions designed to create structural changes must be coordinated with long-term efforts to change social and cultural norms, build on existing community strengths, and change the opportunity costs associated with healthy behaviors to make the healthy choice the default choice, according to the researchers.

“For such interventions to have sustained, intergenerational positive health impacts, they must be coupled with attention to social marketing, behavioral economics, social services, and other supports,” the authors concluded.