Four women sat slumped in their powder blue gowns in Mount Sinai Hospital’s mammography center recently. Each woman hugged herself with both arms, cradling her breasts in between. They sat low and in a row.

Three ladies were black and the other Hispanic.

In Chicago, nearly 80 African-American women die of breast cancer every year because of racial differences in access to healthcare – the worst number of any city in the study, a new study suggests.

Overall, Chicago had the fifth highest gap between breast cancer deaths among black women and white women, according to a report by the West Side-based Sinai Urban Health Institute.

The study, lead by the Institute’s director Steven Whitman, used death certificates to calculate the cancer mortality rates of the 24 largest cities in the United States. It found that black women were more likely to die of breast cancer than white women in almost all of them. Residential segregation and median household income were the only two risk factors to significantly influence racial disparity in breast cancer mortality, because they affect access to care.

“Black people tend to be segregated into these isolated enclaves and they’re far away from facilities that can serve them well and help improve their health,” Whitman said. “Segregation in general has been found to impact many areas of health, and one of them we’ve just discovered is breast cancer.”

Chicago is the most segregated of the 10 largest U.S. cities, according to a January report by the Manhattan Institute for Policy Research based on census data.

Centralized system part of the problem?

The distance from facilities can deter regular screening, which in turn means breast cancer is often diagnosed when it has reached a late stage, according to Jennifer Orsi, a co-author of the study and senior data coordinator at the Metropolitan Chicago Breast Cancer Task Force. The nonprofit organization focuses on fighting health inequalities.

Cities with higher mortality rates were also those with centralized public health systems, as in Chicago and Los Angeles, said Richard Warnecke, professor emeritus of epidemiology, public administration and sociology at the University of Illinois at Chicago. In contrast, New York City’s health system is decentralized with public hospitals dispersed throughout its boroughs.

“Here we have Provident and Cook County [hospitals], and that’s for the whole county,” Orsi said. “New York City’s public health system is funded at a much higher rate, as is their Medicaid rate. When you factor all of those, they can all play a role in addition to segregation.”

But the problem is not that black women are dying from breast cancer more than they were in the past, but that white women are dying less, according to a 2008 paper published in the journal Cancer Causes Control. The mortality rate for black women has remained the same in the past 20 years; however, the rate for white women decreased in the 1990s due to advances in diagnosis and treatment.

“If [black women] aren’t getting those techniques and they’re not screening, then they’re not going to benefit from them,” Warnecke said.

The Chicago City Council last month took action to improve the distribution of resources. It passed an ordinance opening the way to contract with five area hospitals to provide both screenings and follow-up care. Currently, breast cancer patients may have to go to one clinic for their mammograms and then another clinic to have them read.

While not involved with the Institute’s study, Warnecke has researched economic, racial and ethnic disparities in breast cancer. He places less emphasis on the role of Chicago’s racial divisions on cancer rates.

“I don’t disagree with the findings, but segregation itself probably isn’t a direct effect on health as much as the de facto issue of what’s available in these neighborhoods that are predominantly poor,” he said.