Abstract Body: INTRODUCTION: Obesity is linked to cardiovascular disease (CVD) and excess mortality. However, contemporary data about obesity trends in disaggregated Asian American, Native Hawaiian and other Pacific Islander (AANHPI) adults are lacking, especially among younger adults. We examined temporal trends in high body mass index (BMI) and obesity among AANHPI compared to non-Hispanic White (NHW) adults aged 30-49y receiving care in a large California healthcare system.

METHODS: Among adults aged ≥30y with no prior CVD who were Kaiser Permanente Northern California members in 2012-2022, we ascertained the first BMI per person per calendar year (2010-2023) at ages 30-49y. BMI ≥27.5 (lower intervention threshold for Asian adults) and BMI ≥30 kg/m2 (obesity) were classified for all groups. Sex-specific prevalence estimates were age-standardized to the overall population aged 30-49y with measured BMI. To estimate trends in prevalence of high BMI over time, we conducted sex-stratified modified Poisson regression models for both BMI outcomes with calendar year, race/ethnicity, age at BMI, and an interaction term between race/ethnicity and calendar year as covariates with a robust variance estimator to account for within-person clustering.

RESULTS: Among 1,284,415 adults aged 30-49y (mean age 40±6, 61% women), 89,067 (6.9%) were Chinese, 86,683 (6.7%) Filipino, 21,591 (1.7%) Native Hawaiian/Pacific Islander, 68,633 (5.3%) South Asian, 29,512 (2.3%) Vietnamese, 18,240 (1.4%) other Southeast Asian, 8148 (0.6%) Japanese, 9306 (0.7%) Korean, and 953,235 (74.2%) NHW. Age-adjusted prevalences of BMI ≥27.5 and BMI ≥30 were generally higher for men than women, highest for Native Hawaiian/Pacific Islander adults, and lower for East Asian, Vietnamese, and South Asian compared to NHW adults across all years (Figures 1-2). From 2010 to 2023, prevalence of high BMI accelerated fastest among Filipino and other Southeast Asian vs NHW adults (p<0.001). By 2023, the prevalence of high BMI among Filipino and other Southeast Asian adults approached that of NHW adults.

CONCLUSIONS: High BMI/obesity prevalence and trends vary significantly across AANHPI subgroups compared to NHW adults aged 30-49y receiving care, with Native Hawaiian/Pacific Islander adults having the highest burden and Filipino and Southeast Asian adults experiencing rapid increases. These findings underscore the need for effective interventions targeting obesity among younger AANHPI adults to prevent CVD and adverse outcomes.