5 Questions: Rita Hamad on why living in poor neighborhoods could be bad for your health

The Stanford researcher co-authored a new study showing that refugees assigned to the most deprived Swedish neighborhoods were 15 to 30 percent more likely to develop Type 2 diabetes.

- By Kris Newby

Rita Hamad

In the 1980s, as a wave of refugees entered Europe, the Swedish government established an immigration policy that dispersed families to neighborhoods distributed across the country in an almost random fashion. This strict dispersal policy unwittingly created the perfect setup for a natural experiment in which researchers could look for causal relationships between neighborhood quality and population health.

Three decades later, a research team from the Stanford School of Medicine, UC-San Francisco and Lund University, in Sweden, used this natural experiment to look at the effects of neighborhood quality on diabetes risk in a study published April 27 in The Lancet Diabetes & Endocrinology.

In this study, the researchers found that refugees assigned to housing in deprived neighborhoods had a 15 to 30 percent higher chance of developing Type 2 diabetes than counterparts assigned to less-deprived areas. These data were culled from records of 61,386 immigrants, ages 25 to 50, who arrived in Sweden between 1987 and 1991.

Study co-author, Rita Hamad, MD, MS, MPH, an instructor of medicine at Stanford, recently shared her thoughts with writer Kris Newby about this research, and how it might be used to help governments assimilate refugees who have recently fled the war-torn country of Syria.

Q: How did you determine neighborhood quality from data?

Hamad: Sweden, like many European countries, collects centralized, real-time data on health-care access, medication prescriptions, income, housing, education and how many people live in each home. We don’t have that kind of data access in the United States.

For the Sweden study, we created a composite ranking that factored in levels of poverty, unemployment, average schooling and how many people were enrolled in social welfare programs. Then we categorized neighborhoods as high-deprivation, moderate-deprivation or low-deprivation.

Q: Why do poor neighborhoods increase diabetes risk?

Hamad: We’re still working on this analysis, but we hypothesize that deprived neighborhoods make it harder for residents to access healthy foods and good health care. There may be fewer opportunities for education and employment, making it harder for them to purchase quality food and health care. And the chronic stress associated with living in a high-poverty or high-crime area might contribute to the onset of diabetes.

Q: What was the most surprising finding?

Hamad: After analyzing 10 to 20 years of health data, we were surprised to find that living in a deprived neighborhood had a cumulative effect on diabetes risk, even when about half of the refugees later moved to a different neighborhood. Their diabetes risk increased by 9 percent on average for every five years after they were settled in high-deprivation areas.

Q: Based on these findings, what will you research next?

Hamad: We want to do this analysis in other settings and countries. Denmark is next, and we will be traveling there in May with funding from Stanford’s Center for Population Health Sciences. It’s pretty amazing that we will be able to access several decades’ worth of health and socioeconomic data on almost all 5.6 million individuals living in Denmark.

Within Sweden we’re continuing to work with our collaborators at Lund University. They have a lot of great data on neighborhood characteristics such as walkability and food access. Next, we want to analyze the effect of neighborhood quality on other outcomes like mental health or child health.

Q: How might your findings influence policy abroad and in the United States?

Hamad: Our data suggest that decisions affecting the settlement and integration of immigrants can have long-term consequences for the health of the new arrivals, and that these societies may end up paying the price decades later if refugees don’t receive adequate support upfront.

Even though the U.S. doesn’t have a national health-care program like Sweden’s, the health care of vulnerable populations such as refugees eventually hits everyone’s bottom line. People with poor health-care access end up in emergency rooms and on Medicare and Medicaid, and these costs get passed on to taxpayers. Our study suggests that making upfront investments in social services and better neighborhoods for disadvantaged groups can prevent costly chronic diseases such as diabetes.    

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2023 ISSUE 1

How social factors make or break us