Higher levels of racial segregation are associated with a greater rate of HIV diagnoses among African-American heterosexuals, aidsmap reports.

Publishing their findings in the Journal of Urban Health, researchers analyzed segregation patterns from 2008 to 2015 in 95 large metropolitan statistical areas (MSAs). (Such areas may contain the area surrounding a city and sometimes may include more than one city provided those cities are relatively adjacent.)

The investigators looked at the relationship between two main variables: the degree of segregation as measured by the Massey and Denton isolation index and the rate of newly diagnosed HIV per 10,000 adult Black heterosexuals. Their analysis added a one-year lag time between these two variables, to allow for the potential for changes in the segregation level one year to, at least in theory, yield a change in HIV diagnosis rate the following year. So they considered 2007 as the study period’s start year for the isolation index measurement.

In their analysis, the study authors controlled for various factors that also might have affected HIV diagnosis rates, including local inequalities in education, education, employment and poverty rates.

The median Black isolation index was 36.6 percent in 2007. This means that in half of the MSAs, African-American residents lived in a census area in which at least 36.6 percent of people were also Black. The index did not change much over time; it was 34.3 percent in 2015.

During the study period, the annual rate of new diagnoses among Blacks declined by 37.5 percent.

A reduction of one standard deviation from the 2007 average segregation index was associated with a 16.2 percent reduction in the rate of new HIV diagnoses. Over time, one standard deviation reduction in the segregation index was associated with a 4.6 percent decrease in new HIV diagnoses, suggesting a relationship between a decrease in segregation and a decrease in HIV diagnoses.

The study authors’ investigation of factors that may have mediated, or driven, the apparent association between segregation and HIV diagnoses led them to theorize that socioeconomic inequality between Blacks and whites was such a driver.

“The findings further emphasize the need to address segregation as part of a comprehensive strategy to reduce racial inequities in HIV,” the study authors concluded.

To read the aidsmap article, click here.

To read the study abstract, click here.