Disparities in cancer mortality patterns: a comprehensive examination of U.S. rural and urban adults, 1999-2020
Introduction
Cancer mortality rates overall in the U.S. have decreased considerably; however, the rate of decline has not been equal across sociodemographic groups. Unlike urban communities, rural populations have poorer outcomes, particularly for preventable cancers, due to limited access to evidence-based interventions (including smoking cessation and cancer screening) and slower dissemination of medical advancements. Rural areas have higher mortality rates for smoking-related cancers (lung cancer) and cancers that can be prevented or detected earlier by screening (colorectal and cervical cancers). Cancer screening rates are lower in rural than in urban U.S., which may be exaggerated, especially among racial and ethnic minorities in rural communities. We aimed to compare trends in cancer mortality rates from 1999 to 2020 between rural and urban individuals and examine whether any rural-urban differences are uniform across racial and ethnic groups.
Methods
We analyzed annual cancer mortality data from the National Center for Health Statistics (NCHS), over 22 years, from January 1999 to December 2020, among individuals aged 25 years or older. Our primary analysis focused on sex-specific age-adjusted cancer mortality rates by rural-urban classification among U.S. adults aged 25 years or older. We estimated average annual percentage change (AAPC) in age-standardized cancer mortality rates in the U.S. by cancer type, rural-urban status, sex, and race and ethnicity.
Results
A total of 12,580,140 cancer deaths occurred between 1999 and 2020 among individuals in the U.S. aged 25 years or older. The age-adjusted death rate was 282.7 per 100,000 population among rural persons (346.8 per 100,000 males; 235.3 per 100,000 females) and 258.2 per 100,000 population among urban persons (311.2 per 100,000 males; 221.4 per 100,000 females). There was a larger reduction in cancer mortality rates among individuals from urban (males: AAPC, -1.96%; 95% CI, -2.03, -1.90; females: AAPC, -1.56%; 95% CI, -1.64, -1.48) than rural (males: AAPC, -1.43%; 95% CI, -1.47, -1.39; females: AAPC, -0.93; 95% CI, -1.03, -0.82) areas. AAPCs for cancer types were uniformly higher in urban areas compared with rural areas. Despite overall decreases, deaths rates for liver and pancreas cancers increased, including in the most recent period among males (2012-2020, APC, 1.34; 95% CI, 0.49, 2.20) and females (2013-2020, APC, 1.52; 95% CI, 0.03, 3.02) in rural areas.
Conclusion
Cancer death rates decreased in all racial and ethnic populations; however, the rural-urban differences varied by race/ethnicity. The decline in mortality rates was lower in rural areas than in urban communities, and death rates for liver and pancreas cancers increased, particularly for individuals living in rural America.