Manuscript Submission: Temporal trends and disparities in Metabolic Syndrome prevalence (2015–2025): a dual-scale analysis of Electronic Health Records data

Abstract Background Understanding temporal trends in Metabolic Syndrome (\(\:\text{M}\text{e}\text{t}\text{S}\)) prevalence is essential for public health planning especially following macro-environmental shocks. The objective of this study was to quantify the annual percentage change (APC) and annual percentage point change (APPC) in the prevalence of \(\:\text{M}\text{e}\text{t}\text{S}\) in Indiana, United States. Methods Retrospective serial cross-sectional study utilizing electronic health records data between 2015 and 2025. Exposures included time (years), age, sex, and race/ethnicity. The primary outcomes were \(\:\text{M}\text{e}\text{t}\text{S}\:\)prevalence, the APC and APPC in prevalence. Results \(\:\text{M}\text{e}\text{t}\text{S}\) prevalence increased from 21.4% in 2015 to 35.1% in 2025. The cohort-wide relative trend was stable with APC of 4.8% [4.5%–5.1%]; p < 0.001. Overall pre-pandemic absolute growth (APPC = 0.90, 2015–2020) nearly doubled following a 2020 structural break (APPC = 1.71, 2020–2025; p = 0.005). Accelerations were concentrated in younger cohorts: adolescents (ages 12–19; APPC 0.10 to 0.88, p < 0.001) and young adults (ages 20–39; APPC 0.70 to 2.05, p = 0.001), while older adults maintained uninterrupted growth. Divergent structural shocks emerged by race/ethnicity, with significant post-2020 accelerations among NH White (APPC 0.97 to 2.04, p = 0.010), NH Asian (APPC 1.10 to 1.72, p = 0.041), and NH AI/AN (APPC − 0.25 to 1.61, p = 0.030) populations. In contrast, NH Black and Hispanic/Latino cohorts exhibited continuous high growth without discrete pandemic breakpoints. Conclusions \(\:\text{M}\text{e}\text{t}\text{S}\) prevalence rose between 2015 and 2025, with an absolute breakpoint around 2020/21. The systemic shock disproportionately changed trends of certain demographics including adolescents and young adults. Population surveillance could benefit by tracking absolute volume expansions alongside relative rates to guide targeted, equitable structural interventions.