Sociodemographic differences in lung cancer mortality trends across the United States (US) rural-urban divide.

Abstract

11048 Background: It is known that rural populations face higher lung cancer mortality than urban populations, but it is unknown how trends vary across demographic groups. We investigated rural-urban disparities in age-adjusted mortality rates (AAMRs) from lung cancer across demographic groups over 20 years. Methods: We analyzed lung cancer mortality (ICD codes C34.0 - 34.3, 34.8, 34.9) from 1999-2019 using the CDC WONDER database. Populations were classified as urban or rural based on 2013 US census definitions. AAMRs were calculated as deaths per 100,000 using the US Standard Population and stratified by sociodemographic categories. Annual percentage change (APC) and 95% CIs were estimated using linear regression with the log-scale AAMRs as the dependent variable and year as a continuous covariate. Results: There were 3,244,056 deaths attributable to lung cancer (79.7% urban, 20.3% rural) with overall AAMR reduction from 86.9 to 53 deaths per 100,000 from 1999-2019. Rural populations had slower mortality improvements compared to urban populations (APC -2.6 [-2.9, -2.4] vs -1.6 [-1.9, -1.3]; p <0.001), with greatest rural-urban differences seen in younger and female populations (Table). Younger adults (<65)in rural areas had nearly 2-fold slower improvement than urban areas (APC -2.1 [-2.3, -1.9] vs -3.7 [-3.9, -3.5]; p<0.001). Females in rural areas had 3-fold slower improvement than females in urban areas (APC -0.6 [-0.9, -0.3] vs -2.0 [-2.3, -1.7], p<0.001). Slower mortality improvements were also seen for non-Hispanic patients in rural than in urban areas. While AAMR remained slightly higher for Hispanic patients in rural than urban areas, it noted faster improvement in rural areas (APC -3.3 [-3.7, -3.9] vs -2.4 [-2.7, -2.2]). Conclusions: Patients in rural areas had higher AAMR than urban counterparts across all demographic groups analyzed with slower improvements in almost all subgroups. This study highlights populations in greatest need of health services initiatives such as tobacco cessation efforts, lung cancer screening, and guideline concordant treatment receipt to close the rural-urban gap. Overall Urban Rural P Overall -2.5 (-2.7, -2.2) -2.6 (-2.9, -2.4) -1.6 (-1.9, -1.3) <0.001 Age 25-65 -3.4 (-3.6, -3.2) -3.7 (-3.9, -3.5) -2.1 (-2.3, -1.9) <0.001 Age >65 -2.1 (-2.5, -1.8) -2.3 (-2.6, -2.0) -1.4 (-1.8, -1.1) 0.006 Female -1.7 (-2.1, -1.4) -2.0 (-2.3, -1.7) -0.6 (-0.9, -0.3) <0.001 Male -3.2 (-3.4, -2.9) -3.3 (-3.6, -3.1) -2.5 (-2.8, -2.2) 0.002 Hispanic -2.5 (-2.8, -2.3) -2.4 (-2.7, -2.2) -3.3 (-3.7, -2.9) 0.025 Non-Hispanic Black -3.0 (-3.2, -2.7) -3.1 (-3.4, -2.8) -2.1 (-2.4, -1.9) 0.002 Non-Hispanic White -2.24 (-2.5, -2.0) -2.4 (-2.7, -2.1) -1.5 (-1.8, -1.2) 0.002 APC for overall, urban, and rural geographic regions by demographic subgroups. P value for difference in change in AAMR over time between Urban and Rural areas, overall and within subgroups, estimated using interaction tests. All CIs are 95%.