Rural-urban disparities in lung cancer-related mortality in the United States.

Abstract

186 Background: Lung cancer survival outcomes have improved substantially over the last two decades, largely due to the advent of immunotherapy and targeted therapy. However, it is still the leading cause of death among all malignancies in the United States (U.S.). It is hence vital to identify the disparities between different population groups to further decrease lung cancer-related mortality. We, therefore, sought to analyze the outcome variances between urban and rural populations. Methods: We retrieved the mortality data from the Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research (CDC WONDER) multiple causes of death database (years: 1999–2020). We analyzed age-adjusted mortality rates (AAMRs) per 100,000 population and assessed temporal trends in the average percent change (APC) of AAMRs by applying the simplest model with a maximum of 3 joinpoints (using the Joinpoint regression program 5.0.2). We conducted nonparallel pairwise comparisons to assess differences in trends between large metropolitan, small/medium metropolitan, and rural areas (per National Center for Health Statistics Urban-Rural Classification Scheme, 2016) using average annual percentage change difference (AAPCD). Results: A total of 5,409,649,211 lung cancer-related deaths were retrieved from CDC Wonder between 1999-2020, amongst which 2,972,877,175 (54.9%) were in the large metropolitan, 1,622,092,262 (30%) were in the small/medium metropolitan, and 814,672,274 (15.1%) were in the rural regions. We noted a decline in the AAMR overall and across large metropolitan, small/medium metropolitan, and rural areas (table). However, the decline in AAMR was significantly higher among large metropolitan areas as compared to small/medium metropolitan (AAPCD -0.5257, 95% CI -0.93, -0.11, p=0.012) and rural areas (AAPCD: -1.2617, 95% CI -1.67, -0.85, p<0.000001). A similar difference was also distinguished when the small/medium metropolitan group was compared with the rural group (AAPCD -0.7360, 95% CI -1.14, -0.32, p=0.0004). Conclusions: We identify discrepancies in the decline in lung cancer AAMR between urban and rural areas. A substantially lower decline in AAMR is eminent in the rural regions, as compared to the urban counterparts. This raises the concern for poor access to cancer care in this population group. Our results, therefore, emphasize the imperative of prioritizing and designing strategies to ensure healthcare equity.[Table: see text]