MONDAY, May 15, 2017 (HealthDay News) -- Getting out of a segregated neighborhood might make a difference to your health. Black Americans who moved to more integrated areas saw their blood pressure decline between 1 and 5 points, researchers say.
Overall, blacks who moved out of a highly segregated neighborhood tended to experience a 1-point decrease in their systolic blood pressure, said lead researcher Kiarri Kershaw.
Blacks who leave segregation behind for good do even better, added Kershaw, an assistant professor of preventive medicine at Northwestern University's Feinberg School of Medicine in Chicago.
Those who permanently moved to moderately segregated neighborhoods underwent a 3-point decrease in blood pressure on average, while those who moved to a low-segregation neighborhood had a 5-point decrease, Kershaw said. The study followed the participants for 25 years.
Systolic blood pressure, the first number in a blood pressure reading, is an indicator of heart attack and stroke risk.
The prevalence of high blood pressure among black men and women in the United States is among the highest in the world, according to the American Heart Association. More than 40 percent of black Americans have high blood pressure, which develops earlier in life and is usually more severe than in other racial groups.
Kershaw believes the stress that comes with living in a segregated neighborhood is driving these higher blood pressure rates.
"In a less violent area with better resources, you are more secure about your family's safety and your children's future in better schools," Kershaw said in a Northwestern news release. "You see opportunities for the economic mobility of your kids. And there is better access to good grocery stores, health care and an economically vital business district."
For this report, Kershaw and her colleagues tracked more than 2,000 black Americans participating in a federally funded long-term study of heart disease.
The participants were 18 to 30 years old when they entered the study, and between 43 and 55 at follow-up. They lived in one of four locations -- Birmingham, Ala., Chicago, Minneapolis and Oakland, Calif.
The researchers analyzed census data to figure out whether each participant lived in a racially segregated neighborhood at the start of the study or at follow-up. The racial makeup of their neighborhood was compared with that of the city or county in which they live to rank its level of segregation as high, moderate or low.
The findings were published May 15 in JAMA Internal Medicine.
The study didn't prove that living in an all-black neighborhood leads to high blood pressure, or hypertension.
Still, the new findings could help doctors figure out why people from a particular neighborhood in their city are having a tougher time controlling their blood pressure, said Dr. Eduardo Sanchez, the American Heart Association's chief medical officer for prevention.
"Maybe where you live makes a difference," Sanchez said. "Zip codes matter."
Doctors can respond to this factor by changing up a person's blood pressure medications or emphasizing lifestyle changes such as eating right or exercising, Sanchez said.
"Blood pressure control is about a variety of things, and the effect of a neighborhood is just one of them," Sanchez said.
Doctors can use the study itself to start a conversation with patients from racially segregated areas, letting them know their locale creates a greater challenge in controlling their blood pressure, Sanchez said.
At a higher level, this study shows the importance of policies that either improve the quality of segregated neighborhoods or open up housing markets to give people opportunities to live elsewhere, Kershaw said.
Economic investment in these neighborhoods can help. Kershaw pointed to policies that are establishing new grocery stores in urban "food deserts," which help people eat healthier and also provide jobs in the community.
School districts also can help moderate this effect by trying to distribute resources more equitably across all schools, which would help improve education in segregated neighborhoods, Kershaw said.
"This paper points to the importance of thinking of the health implications of social policies," Kershaw said.
For more on high blood pressure and race, visit the American Heart Association.