Place of living increasingly determines where historic drop in cancer mortality reaches

In 1991, the U.S. experienced a significant shift in cancer death rates, as, for the first time, deaths began a steady decline that continues to the present day. Researchers at Mississippi State’s Social Science Research Center, in partnership with scientists at Oak Ridge National Laboratory, examined this decline to identify where and who benefited the most from this dramatic improvement.

In the British Journal of Cancer, a recent article from MSU SSRC Giles Distinguished Professor Emeritus Arthur G. Cosby and a team of researchers analyzed cancer deaths in almost 3,000 U.S. counties from 1981–2019, finding urban and affluent counties were more likely to experience a significant decline in cancer mortality.

“The dramatic reduction in cancer deaths occurs so unevenly across America, and there are many Americans who are not sharing this important improvement in the nation’s health,” Cosby said. “By identifying the place-based differences in cancer decline, we can gain insights into the forces limiting improved cancer health at the local level.”

The article “Who is Benefiting from the Dramatic Decline in U.S. Cancer Mortality?: Place-Based Evidence of Disparities in Rates of Improvement” explores the forces and characteristics that contribute to these differences in the mortality decline. In 1991, when the cancer rate peaked, there were initially few differences between counties with the highest and lowest income levels. By 2019, 10% of the population living in the highest-income counties had mortality improvements roughly 7 times greater than those 10% living in the lowest-income counties.

“Place can make a huge difference in health outcomes, and this was certainly true for county cancer mortality. The geographic differences were stark,” Cosby said. “The large urban centers along both the Atlantic and Pacific coasts consistently had among the highest rates of cancer improvement. At the same time, rural and smaller cities in the interior of the U.S. often had much lower rates.”

Death certificates from more than 23 million cancer deaths collected by the Centers for Disease Control and Prevention were used in this study. The period was selected to capture the transition period: the earlier period of increasing mortality, the peak transition point of 1991 and the current period of declining cancer mortality.

Cosby said health researchers attribute the decline in cancer mortality to a considerable range of health interventions. These include preventive measures and improvements in cancer treatment. He cites, for example, the decline in tobacco use brought about by health warnings, higher taxes on cigarettes, and smoke-free laws, and said it is likely county differences in cancer improvement are a result, in part, from differences in the county level of utilization and acceptance of health practices.

“Wealthy, metropolitan New York City has been aggressive in instituting tobacco control measures, and the results show. Manhattan Borough had a lung cancer rate of 49 per 100,000 in 1991. By 2019, it cut its rate to 19.6—a 60% reduction,” Cosby said.

Cosby led this study along with Viswadeep Lebakula, a lead scientist on the LandScan Global Project at Oak Ridge National Laboratory, and Gina Mendez Rico, assistant SSRC research professor. Other authors were Karissa Bergene, assistant director of research operations at George Mason University’s Center for Resilient and Sustainable Communities; Mackenzie Bumgarner, a former SSRC undergraduate research assistant; and Alina Peluso, a research scientist at Oak Ridge National Laboratory.