There are many benefits from living in more diverse and integrated neighborhoods, and a recently published study funded by the National Heart, Lung, and Blood Institute (NHLBI) provides additional evidence that moving to more integrated neighborhoods has health benefits.
Kershaw and colleagues examined 25 years of longitudinal data of 2280 Black participants in the Coronary Artery Risk Development in Young Adults (CARDIA) project to determine the effect of racial residential segregation on blood pressure. Controlling for potential confounds including age, sex, marital status, education, and neighborhood poverty and density, participants exposed to less segregated neighborhoods experienced over a 1 mm Hg reduction in systolic blood pressure. Among those who made more permanent moves to lower segregated neighborhoods (i.e., did not move back to highly segregated neighborhoods), their blood pressure dropped by 5.71 mm Hg on average.
These findings, while longitudinal, are still correlational, and those more likely to move to less segregated neighborhoods (or whose neighborhood became less segregated over time) may be different in unknown ways from those who did not move. Over 25 years, however, nearly everyone (94%) moved at least once. While such findings cannot posit that Blacks who move to more integrated neighborhoods will experience a nearly 6 mm Hg reduction in systolic blood pressure, these findings are consistent with prior research showing that those who were randomly selected to receive housing vouchers to move to lower poverty neighborhoods experienced less obesity and diabetes than those who were not selected for such vouchers.
Should we be impressed with a 1.3 or 5.7 mm Hg reduction in systolic blood pressure? Population models of blood pressure indicate that a 1 mm Hg systolic reduction among Blacks, who have disproportionately higher rates of hypertension and cardiovascular disease, would result in 20.3 fewer heart failure events per 100,000 person‐years. In the recently published HOPE-3 trial, the combination of candesartan and hydrocholorothiazide produced a 6.0 mm Hg reduction in systolic blood pressure. Therefore, the reductions in systolic blood pressure observed in the CARDIA study among Blacks who move from high to low segregated neighborhoods are comparable to the reductions found in those with intermediate cardiovascular risk treated with hypertensive medications.
These observed systolic blood pressure reductions associated with moves from high to low segregated neighborhoods are also comparable to the systolic blood pressure reductions found in trials of behavioral changes such as increased exercise (6.1 mg Hg), dietary modifications (6.0 mg Hg), sodium restriction (4.7 mg Hg), relaxation training (4.0 mm Hg), reduced alcohol consumption (3.8 mm Hg), calcium supplements (2.5 mm Hg) and fish oil supplements (2.3 mm Hg).
May is National High Blood Pressure Education Month, and we clearly have a range of interventions available to reduce systolic blood pressure and subsequently reduce the risk of cardiovascular disease and stroke. There is much more to learn about the mechanisms that account for the reductions in blood pressure observed from moving to low segregated neighborhoods, and a causal relationship needs to be established, but the current evidence suggests that in addition to considering a range of medications and behavioral interventions to reduce systolic blood pressure, we should also strongly consider policy changes that encourage more integrated neighborhoods. Living in a diverse and integrated community has many benefits, and improved health appears to be one of them.