When the second-most frequent cause of death in the nation begins to decline, the effects are considerable. Improvements in cancer screening, treatment and prevention have led to increases in longevity and well-being.

In a diverse country, however, not everyone or every place benefits equally from improvements in health and medicine. In coordination with my colleague Viswadeep Lebakula, research from my team of social scientists and I found that where people live can profoundly influence their chances of dying from cancer.

Rural mortality penalty

While national data on cancer deaths can provide a useful report card on how successful a country has been on improving its health, it can also mask large geographic differences.

My team and I examined cancer deaths rates for almost 3,000 U.S. counties between 1981 and 2019. By looking at cancer mortality at the county level, we found a more complex picture of changing cancer death patterns than just examining the country overall.

Specifically, geographic differences between who benefited from the medical and public health improvements that reduced cancer deaths were stark.

Large urban centers along both the Atlantic and Pacific coasts consistently had the highest rates of cancer improvements. The heavily populated corridor from Boston to Washington, D.C., had steep declines in cancer deaths. For example, the four largest boroughs in New York City – Manhattan, Queens, Bronx and Brooklyn – saw cancer death rates decline over 40% between 1991 and 2019. The largest and wealthiest borough, Manhattan, had the highest improvement at 47% fewer deaths.

Similarly, large coastal urban centers, such as Miami, the San Francisco Bay Area, Los Angeles, San Diego and Seattle, saw very large improvements in cancer mortality. In the San Francisco Bay Area, for example, wealthy urban counties had decreases in cancer rates that substantially exceeded the national rate of 34%. Specifically, Marin County saw a 47% decline, San Mateo County a 44% decline and San Francisco County a 40% decline.

It is a much different story for rural counties in the middle of the country.

Prior to 1991, rural and urban America generally shared similar rates of cancer mortality. When the national rate started to decline, however, rural and small-town America lagged behaind large urban centers. These nonmetropolitan areas had much lower rates of declining cancer deaths: 20% for Mississippi, 23% for Arkansas, 24% for West Virginia and 29% for Montana. Around 458 rural counties even experienced increasing cancer mortality.

Notably, these differences in cancer mortality between rural and urban counties were originally small and only began to increase when overall national cancer rates began to drop. The cancer rate in rural, small-town America was improving overall, but metropolitan America was improving substantially faster.

These disparities suggest that the medical and social changes leading to reduced cancer mortality were concentrated in more metropolitan regions.

Higher income, fewer cancer deaths

We found that county median family income had a strong influence on cancer death rates.

When cancer death rates peaked in 1991, there was initially little difference between counties with the highest and lowest income levels. By 2019, the 10% of the U.S. population living in counties with the highest median incomes had mortality improvements approximately seven times greater than the 10% living in the lowest-income counties.

The overall pattern was very clear: As county income increased, improvements in cancer mortality increased. Counties with the least financial capacity to deal with the burden of cancer saw the least improvement.

The American Cancer Society and the Centers for Disease Control and Prevention have identified multiple factors underlying declining cancer death rates. These include advances in cancer prevention, screening and treatment. But there are considerable county and state differences in the adoption of preventive measures and access to cancer services.

For example, lung cancer is the leading cause of cancer deaths and has seen the strongest decline in death rates. Tobacco control strategies – smoking cessation programs, health warnings, increased taxes on tobacco products, bans on tobacco purchases by minors and smoking in public place – have been especially successful in reducing deaths from lung cancer. Geographic differences in adoption of these tobacco control measures can partially explain why some places have higher cancer death rates compared to others, especially for lung cancer.

For example, New York City aggressively instituted tobacco control measures, and the results show. My team found that New York’s Manhattan borough had 60% fewer lung cancer deaths in 2019 compared to 1991. At the same time, many states and counties – often rural and less affluent – have adopted fewer and weaker tobacco control measures. Rural communities often have higher smoking rates and exposure to tobacco smoke in the home, along with fewer smoke-free laws and less support for tobacco control policies.

Innovation over access

Cancer can devastate families and communities, both emotionally and economically. The U.S. has become more successful in developing innovations to treat cancer than in equitably distributing these innovations across the nation.

While most of the U.S. is experiencing improvements in cancer mortality, these benefits are greatest in urban and wealthy areas. Developing tobacco control policies and screening techniques tailored to rural settings, as well as increasing access to advanced treatments in rural and poor settings, could help improve cancer mortality for more people.

Will the gap between rural and urban America – and the gap between rich and poor America – decline or grow? Answering this question will require a better understanding of the unique needs of everyday people in their communities.

Arthur Cosby, Professor of Sociology, Mississippi State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.