Aldosoky, Wesam

Abstract Background Obesity is a major public health concern and a leading contributor to premature mortality worldwide. While body mass index (BMI) has long been the standard measure for assessing obesity-related health risks, it fails to distinguish between fat and lean mass or capture the distribution of adiposity—key determinants of metabolic and cardiovascular (CV) health. The Body Roundness Index (BRI), a novel anthropometric measure incorporating waist circumference and height, offers a more precise assessment of body fat distribution and its associated health risks. Although prior studies have linked BRI to all-cause and CV mortality in general populations, its predictive value for premature mortality and potential disparities remain unexplored. Purpose To investigate the association between BRI and premature all-cause (primary outcome) and cardiovascular-specific mortality (secondary outcome) in U.S. adults younger than 65 years. Additionally, we examine whether these associations vary across sociodemographic subgroups. Methods We conducted a nationally representative cohort study using the National Health and Nutrition Examination Survey (NHANES) data (1999–2018) linked to mortality records through December 31, 2019. Adults younger than 65 years were included, excluding those with CV disease or missing covariates. BRI, derived from waist circumference and height, was categorized into quintiles (Q3 as reference). Premature mortality was defined as deaths before age 65. Multivariable Cox proportional hazards models, accounting for NHANES’ complex survey design, were used to assess associations and ensure nationally representative estimates. Nonlinear relationships were examined using restricted cubic splines. Results Among 29,016 (weighted N=1,349,437,788) adults (mean age 42 years; 50% female), 751 premature deaths occurred over a median follow-up of 10 yrs, including 163 attributed to CV causes. In fully adjusted models*, participants in the highest BRI quintile (Q5 vs. Q3) had a 47% higher risk of premature all-cause mortality (HR 1.47; 95% CI, 1.12–1.93; p=0.006) and a 96% higher risk of premature cardiovascular mortality (HR 1.96; 95% CI, 1.12–3.41; p=0.02; Fig.1). Subgroup analyses indicated that the association between high BRI and premature mortality was most pronounced among middle-aged adults (45-64 years: HR 1.80; p-interaction=0.004), males (HR 1.66; p=0.006), and Hispanics (HR 2.17; p=0.007). Similar patterns were observed for premature cardiovascular mortality (Fig.2). Conclusions High BRI is independently associated with increased risks of premature all-cause and cardiovascular mortality, with the strongest effects observed in middle-aged adults. These findings highlight the potential of BRI in risk stratification and underscore the need for targeted interventions to address disparities in premature mortality. Integrating BRI into preventive cardiology and public health strategies may help reduce early mortality.Figure 1 Figure 2

Abstract Aims Obesity, particularly visceral adiposity, is a key driver of cardiovascular mortality (CVM), yet conventional measures such as body mass index (BMI) inadequately capture fat distribution. The Body Roundness Index (BRI) is a novel anthropometric measure integrating waist circumference and height to better reflect body shape and visceral fat. This study examined the association between BRI and CVM in U.S. adults and across sociodemographic subgroups. Methods and results We analysed data from 31 351 adults (median age 43 yrs, 50% females) aged ≥20 years in NHANES 1999–2018, excluding those with prior cardiovascular disease or cancer. BRI was computed using a validated equation and categorized into quintiles (Q3 as reference). The primary outcome was CVM; secondary outcomes included all-cause, heart disease, and cerebrovascular mortality. Weighted Cox proportional hazards and restricted cubic spline (RCS) models evaluated associations after adjustment for demographic, behavioural, and clinical factors. Subgroup and sensitivity analyses tested consistency and effect modification. During a median follow-up of 10.1 years (IQR: 5.3–14.9 years), 883 cardiovascular deaths occurred. In fully adjusted models, participants in the highest BRI quintile had a 54% higher risk of CVM (HR, 1.54; 95% CI, 1.13–2.08; P = 0.006) vs. Q3. This risk remained high even among those with normal BMI. RCS analysis indicated a modest U-shaped association. Stronger effects were observed among middle-aged adults (45–64 years) and those with higher educational attainment. Conclusion Higher BRI is independently associated with increased cardiovascular mortality, particularly among middle aged adults and those with normal BMI, underscoring its potential as a practical, noninvasive tool for cardiovascular risk stratification. Incorporating BRI into clinical and public health assessment may improve identification of individuals at elevated risk.