Abstract B099: Association between obesity and mortality by race, ethnicity, and sex in the United States, 1999-2018
Authors: Marlow Emily C. , Thomson Blake , Jemal Ahmedin , Islami Farhad 
Published: December 2023

Abstract
Background The association between obesity and mortality risk is well established. This prospective cohort study will examine whether there are disparities in this across sex and race/ethnicity in the US and provide updated risk estimates for all-cause, cancer, and five other leading causes of death. Methods We created a cohort of 282,602 never-smoking participants using the National Health Interview Survey (NHIS) linked to the National Death Index that follows mortality up to December 31, 2019. We considered participants aged 25-84 years at enrollment, with at least 2 years follow up, and the following race/ethnicity groups: non-Hispanic White[White], non-Hispanic Black[Black], Hispanic, and other. Self-reported BMI values from NHIS were adjusted using the National Health and Nutrition Examination Survey objectively measured BMI averages by sex, race/ethnicity, and education. The adjusted BMI categories included 12-&lt;18.5(underweight), 18.5-&lt;25(healthy weight), 25-&lt;30(overweight), 30-&lt;40(obese), and 40-≤70(severely obese). Adjusted mortality rate ratios (RR) obtained by the Cox proportional hazard model using NHIS complex survey design compared individuals with healthy weight to those with lower or higher BMI by sex and race/ethnicity. Results A total of 22,591 deaths occurred in this study period, of which 4,539 were cancer. In men and women, obesity and severe obesity were associated with higher risk of cancer mortality. Compared to men with healthy weight, the risk of cancer mortality was higher among individuals who were underweight (RR=1.95,95%CI=1.06-3.58), overweight (RR=1.03,95%CI=0.88-1.19), obese (RR=1.30,95%CI=1.11-1.53), and severely obese (RR=1.68,95%CI=1.21-2.32). Among women, the risk for cancer mortality was higher among individuals who were underweight (RR=1.18,95%CI=0.78-1.80), overweight (RR=1.06,95%CI=0.95-1.18), obese (RR=1.17,95%CI=1.04-1.32), and severely obese (RR=1.62,95%CI=1.35-1.93) compared to the risk for those with healthy weight. In general, similar patterns were observed in all-cause and leading causes of death evaluated in this study. Similarly, being underweight, obese, and severely obese, as compared to being healthy weight, was generally associated with all-cause and cause-specific mortality among White and Hispanic populations. However, obesity and severe obesity were not significantly associated with cancer mortality among Black people likely due to sparse data. The magnitude of some mortality associations also differed by sex and race/ethnicity. For example, the association between obesity and all-cause mortality was stronger among Hispanic men (RR=1.64,95%CI=1.33-2.02) compared to Hispanic women (RR=1.10,95%CI=0.94-1.28). The all-cause RR for severe obesity among White females (RR=1.96,95%CI=1.78-2.17) was larger than among Black females (RR=1.52,95%CI=1.31-1.76). Conclusions Higher BMI was associated with higher risk of all-cause and leading causes of mortality by sex and race/ethnicity, emphasizing the importance of interventions to help reduce excess body weight and maintaining healthy body weight.
Citation Format: Emily C. Marlow, Blake Thomson, Ahmedin Jemal, Farhad Islami. Association between obesity and mortality by race, ethnicity, and sex in the United States, 1999-2018 [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B099.