Hypertensive Heart Disease Attributable to High BMI: Global Trends, Gender Disparities, and SDI-Based Inequities (1990–2021)

Background Hypertensive heart disease (HHD) that is responsible for 23% of global cardiovascular deaths is increasingly mediated by high body mass index (BMI > 25 kg/m²). With obesity prevalence tripling since 1975, quantifying the distinct trajectory of BMI-attributable HHD burden across equity dimensions is critical for achieving UN Sustainable Development Goal 3.4. This study analyzed the global burden through gender and socio-demographic index (SDI) strata (1990–2021) and projects trends to 2051. Methods We performed two-sample Mendelian randomization (MR) analyses to investigate the causal association between BMI and HHD risk. Leveraging Global Burden of Disease 2021 data from 204 countries, we assessed HHD mortality and disability-adjusted life years (DALYs) attributable to high BMI via DisMod-MR 2.1. Health inequities were quantified using Slope Index of Inequality (SII) and Concentration Index (CI), with Bayesian age-period-cohort modeling enabling gender-stratified projections. Results MR provided causal evidence that per SD increment in BMI leads to over two times higher odds of HHD (OR: 2.257, 95% CI: 2.09–2.437). Global HHD deaths attributable to high BMI rose 1.48% (95% UI: 1.01–1.98) from 1990–2021, with females experiencing disproportionately higher mortality (+ 1.4%, 0.88–2) and DALYs (+ 1.12%, 0.75–1.67) than males. Southern sub-Saharan Africa recorded the steepest ASMR increase (+ 0.54, 0.33–0.77), while East Asia saw mortality surge + 1.14% (0.43–2.38), epitomizing the socioeconomic paradox where rapid development outpaces health system adaptation. SII inverted from − 13.94 (1990) to 37.59 (2021), signaling expanding absolute inequities. Projections indicate persistently higher female burdens despite declining overall rates post-2030. Conclusion High BMI is a causal risk predictor for HHD. The escalating HHD burden attributed to high BMI constitutes a health equity crisis, disproportionately impacting females and resource-limited regions. Urgent tiered interventions are warranted: implementing gender-integrated screening; enforcing WHO-aligned policies targeting ultra-processed foods; and deploying mobile health units to high-burden rural areas. Future efforts must reconcile economic growth with health system resilience to address the socioeconomic paradox.