Environmental racism may accelerate aging of black Americans: study

BAccording to a new study, Americans who live in neighborhoods with lower levels of income and education may age faster than their white neighbors. This may be true even when a black person has a higher income or education level, which highlights how a person’s environment can impact their health.

THE studypublished Wednesday in PLOS ONE, builds on an emerging body of research that links faster biological aging, measured by a process called DNA methylation (DNAm), low socio-economic status – a term that encompasses education, income and wealth. The University of Pennsylvania research team is the first to show how the neighborhood a person lives in can contribute to racial disparities in accelerated aging, even after controlling for individual socioeconomic status. The researchers found that living in a “disadvantaged” neighborhood — one that includes a greater proportion of low-income residents, among other factors — explains 21% of racial disparity in an mDNA measure.

It’s well established that some people age at different rates than others, said Corey McMillan, an associate professor of neurology at the University of Pennsylvania and one of the paper’s co-authors. But the new study “addresses some of the environmental pressures that contribute to different rates of aging, which black people are more often exposed to due to structural factors like environmental racism.”

This is the phenomenon known as “aging” – the premature biological aging experienced by people in marginalized communities due to stressors like racism and poverty. It has been linked to poorer health outcomes, ranging from hypertension and mental illness at higher infant and maternal mortality. STAT reported Last year on a study showing that the brains of black Americans are aging faster than those of white or Hispanic adults, with signs of dementia appearing in MRIs as early as their forties.

The new study aimed to shed more light on the environmental factors that contribute to inclement weather. The researchers found that PM2.5 Pollution – the amount of very fine particles in the air that are less than 2.5 microns in diameter – has a much greater impact on the accelerated aging of black Americans than white Americans exposed to the same pollution. The researchers also looked atneighborhood deprivation– an index that measures, for example, the proportion of people living in a certain neighborhood with less than 12 years of education or the percentage who do not own a car or who live in overcrowded housing.

It is unclear whether the disparities in the impact of air pollution on aging can be attributed to black participants being more sensitive to pollution or more exposed in ways that are not taken into account in this study, note the authors. Having a history of lung disease or asthma — conditions that disproportionately affect communities of color — could make a person more vulnerable.

Additionally, lead author Isabel Yannatos said, “This cumulative effect of disadvantage and discrimination could lead to a greater amount of stress, which could make someone’s body unable to cope with the pollution of the air.”

Other factors that may influence people’s level of exposure to air pollution, even when they live in the same neighborhood, include varying amounts of time spent outdoors, having a air conditioning unit or air cleaner, the type of job or home a person has and how long they’ve lived in the neighborhood, said Yannatos, a doctoral student in neuroscience at the University of Pennsylvania.

The study focused on data from 2,960 Americans aged 50 or older, drawn from the Health and Retirement Study, a longitudinal cohort study that surveys a representative sample of approximately 20,000 people across the United States. A subset of these participants submitted a blood sample in 2016. The researchers analyzed these samples for patterns of DNA methylation, a biological process that can alter DNA activity, such as levels of gene expression. By examining DNAm data, surveys, and neighborhoods based on participants’ ZIP codes, the researchers used two statistical approaches to analyze how neighborhood and environmental factors contributed to racial disparities in epigenetic aging.

There are other limitations to the study. There’s a big one in the field of social epigenetics, the authors note: a lack of longitudinal mDNA data that follows participants over a longer period of time, not just at one point in time.

“You would expect someone who has lived in a poor neighborhood with a lot of exposure to air pollution all their life to probably be very different from someone who has recently moved into the neighborhood,” said Gloria Huei-Jong Graf, a doctoral student in epidemiology at the Columbia Mailman School of Public Health, who was not involved in the study. “Especially if you think about, what if it’s a gentrified neighborhood? And the people who settle there are better off than those who traditionally live there.

Findings from this type of location-based study also aren’t entirely generalizable, according to Emily Shantz, a Ph.D. candidate who studies health geography at the University of Waterloo. Social systems, with their unique sets of environmental, social and cultural norms, work differently in different places, she told STAT by email.

Shantz noted that it would be interesting to see similar studies in other neighborhoods and with other racial and ethnic groups across the country, to see if there are any changes in the effects on accelerated aging and in how much each factor contributes to the disparities.

“Human bodies don’t live in a vacuum – they constantly interact with all aspects of their environment,” she said. “Based on decades of work by predominantly black feminist scholars, we know that identities and social circumstances don’t add up – they inform each other.”

Future research using a more intersectional approach that reflects these nuanced experiences is also on the authors’ wish list. As important as it is to quantify the contribution of environmental factors to weathering, it is crucial to recognize how other structural and social factors may differentially affect the aging of marginalized groups like black women, the authors note. These can include differences in the accessibility and quality of access to health care, as well as other forms of discrimination and environmental racism.

“My hope is that as a field and as a society, we really start to think about these kinds of environmental and neighborhood factors…as one of the drivers of health in addition to things at the individual level,” said said Yannatos. Once the connection between the neighborhood a person lives in and their individual health is made, she hopes the groundwork will be laid for local and larger-scale policy interventions that could “prevent some of these health issues and disparities.” in health to occur”.