Socioeconomic inequalities in premature cancer mortality among US counties during 1999 to 2018
Menée aux Etats-Unis à partir de données 1999-2018 portant sur des adultes âgés de 25 à 64 ans, cette étude analyse l'évolution des disparités socioéconomiques dans la mortalité prématurée par cancer dans 3 028 comtés
Background: This study investigated socioeconomic inequalities in premature cancer mortality by cancer types, and evaluated the associations between socioeconomic status (SES) and premature cancer mortality by cancer types. Methods: Using multiple databases, cancer mortality was linked to SES and other county characteristics. The outcome measure was cancer mortality among adults aged 25-64 years in 3,028 US counties, from 1999 to 2018. Socioeconomic inequalities in mortality were calculated as a concentration index by income (annual median household income), educational attainment (% with bachelor's degree or higher), and unemployment rate. A hierarchical linear mixed model and dominance analyses were used to investigate SES associated with county-level mortality. The analyses were also conducted by cancer types. Results: Concentration indexes of SES factors varied by cancer types. Low-SES counties showed increasing trends in mortality, while high-SES counties showed decreasing trends. Socioeconomic inequalities in mortality among high-SES counties were larger than those among low-SES counties. SES explained 25.73% of the mortality. County-level cancer mortality was associated with income, educational attainment, and unemployment rate, at −0.24 (95% CI: −0.36, −0.12), −0.68 (95% CI: −0.87, −0.50), and 1.50 (95% CI: 0.92, 2.07) deaths per 100,000 population with one unit SES factors increase, respectively, after controlling for healthcare environment and population health. Conclusions: SES acts as a key driver of premature cancer mortality, and socioeconomic inequalities differ by cancer types. Impact: Focused efforts that target socioeconomic drivers of mortalities and inequalities are warranted for designing cancer-prevention implementation strategies and control programs and policies for socioeconomically underprivileged groups.