Body size and composition trends in U.S. adults with a history of cancer: NHANES 1999–2018

Abstract Purpose High fat mass and low muscle mass are associated with increased mortality and risk of second primary cancers in cancer survivors. This longitudinal study examined trends in body size and composition among US adults with a history of cancer from 1999 to 2018. Methods Data from self-reported cancer survivors aged ≥20 years in the Continuous National Health and Nutrition Examination Survey 1999-2006 and 2011-2018 were analyzed. Outcome measurements included body mass index (BMI, n=3,544) waist circumference (WC, n=3,354), and DEXA-derived indices, including fat mass index (FMI, n=1,767), total lean mass (LM, n=1,775), and appendicular skeletal muscle mass index (ASMMI, n=1,741). Multivariate linear regressions were used to analyze across data cycle associations, adjusting for age, sex, and race/ethnicity. Results Across 19 years, average BMI increased from 27.1 kg/m² to 30.0 kg/m² (p