Cancer Mortality Higher in Counties with Persistent Poverty

An article published in Cancer Epidemiology, Biomarkers & Prevention suggested that cancer mortality was higher in counties that experienced persistent poverty compared to other counties, including those currently experiencing poverty.¹

Persistent poverty, defined by the 2007-2011 American Community Survey, means that a county has had poverty rates of 20% or higher in US Census data from 1980, 1990, and 2000. According to lead author Jennifer L. Moss, PhD, assistant professor in the Department of Family and Community Medicine at Penn State College of Medicine in Hershey, Pennsylvania, these areas, which represent about 10% of all US counties, are primarily located in the rural south.

Counties which have persistent poverty generally have larger populations of racial and ethnic minorities, more children under the age of 18, less formal education, and greater unemployment. Further, they also tend to be more likely to have high rates of cancer risk factors such as obesity or cigarette smoking.

“Counties that have experienced persistent poverty face health risks that have accumulated for decades, and they have fewer current or past resources to protect public health,” Moss noted in a press release.²

In this study, researchers examined cancer mortality rates in persistently poor counties compared with other counties. Notably, the median income in the persistently poor counties was $32,156, compared with $47,154 in the counties not experiencing persistent poverty.

County-level, age-adjusted, overall, and type-specific cancer mortality rates were calculated from 2007-2011. Overall cancer mortality was found to be 179.3 (standard error [SE] = 0.55) deaths per 100,000 people per year in nonpersistent poverty counties and 201.3 (SE = 1.80) in persistent poverty counties (12.3% higher, P < 0.0001).

In multivariate analysis, cancer mortality was also higher in persistent poverty versus nonpersistent poverty counties for overall cancer mortality as well as for several type-specific mortality rates, including lung and bronchus, colorectal, stomach, and liver and intrahepatic bile duct (all P < .05). Moreover, among counties currently experiencing poverty, those that were also experiencing persistent poverty had elevated mortality rates for all cancer types as well as lung and bronchus, colorectal, breast, stomach, and liver and intrahepatic bile duct (all P < .05).

Though the exact reasons for the elevated cancer mortality rates in counties experiencing persistent poverty versus other counties is not yet known, the investigators indicated that along with high rates of cancer risk behaviors and lower rates of cancer screening, larger scale, infrastructural issues, such as reduced access to health care, may have contributed to mortality risk.

“Disinvestment in clinical and public health systems is a problem in any community, but in these persistent poverty counties, which are primarily rural and have had high rates of poverty for more than 30 years, infrastructure may be especially underequipped to deal with the burden of cancer in an aging population now and in the future,” the authors wrote. “It is, therefore, crucial to understand area-level poverty as a marker of exposure to carcinogenic environments.”

Moving forward, the researchers recommended future etiologic research should attempt to better understand the higher rates of cancer mortality in these counties.

Moreover, Moss said that the results of this study suggest that researchers need to distinguish between persistent poverty and current poverty, given that persistent poverty is associated with the strongest risk of cancer mortality. She also said the long-entrenched societal problems surrounding persistent poverty merit local and national interventions to improve health outcomes.

“We need interventions in these communities to change cancer-causing behaviors, to make cancer screening more accessible, to improve treatment, and to promote quality of life and survivorship,” Moss explained. “Efforts to reduce the risk of cancer in these counties will require strategic coordination, collaboration, and funding, with input from community members every step of the way.”

References:

1. Moss JL, Pinto CN, Srinivasan S, Cronin KA, Croyle RT. Persistent Poverty and Cancer Mortality Rates: An Analysis of County-Level Poverty Designations. Cancer Epidemiology, Biomarkers & Prevention. doi: 10.1158/1055-9965.EPI-20-0007

2. Counties with Persistent Poverty Rates Experience Higher Rates of Cancer Deaths [news release]. Philadelphia. Published September 30, 2020. Accessed September 30, 2020.