In a prospective cohort of 400 Black adolescents from lower-income Chicago households, exposure to neighborhood gun violence over the preceding five years was independently associated with a 0.5% lower brachial artery flow-mediated vasodilation (FMD) score — comparing youth at the 75th versus 25th percentile of violence exposure — across three measurement occasions spanning two years. Crucially, two modifiable pathways emerged: central adiposity mediated the concurrent association, while dietary quality mediated the prospective link, both independently of co-occurring stressors including personal victimization, economic hardship, and police misconduct.
Endothelial dysfunction, measurable by FMD, is an established early predictor of atherosclerosis and long-term cardiovascular disease. A 0.5% FMD difference in adolescence may sound modest, but evidence from adult cohorts suggests even small FMD reductions carry compounded lifetime risk — and cardiovascular disparities in Black Americans are already disproportionate. What distinguishes this work is its prospective design and mechanistic specificity: identifying diet quality and waist circumference as tractable intervention targets within a social-determinants framework is genuinely actionable for clinicians and public health planners. Limitations include a single urban cohort limiting generalizability, reliance on waist circumference rather than imaging for adiposity, and no direct dietary biomarker validation. As a preprint posted to medRxiv and not yet peer-reviewed, findings remain provisional and may be refined after expert scrutiny. Still, this research is among the first to longitudinally quantify how structural violence embeds itself biologically in youth arteries.
