AUTHOR=Zhou Junteng , Kong Qihang , Liu Xiaojing , Huang Yan 

TITLE=U-shaped association between myeloperoxidase levels and anxiety risk: a cross-sectional study in a Chinese population

JOURNAL=Frontiers in Public Health

VOLUME=Volume 13 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2025.1596844

DOI=10.3389/fpubh.2025.1596844

ISSN=2296-2565

ABSTRACT=ObjectiveThis study investigates the association between myeloperoxidase (MPO) levels and anxiety risk in Chinese adults and explores potential effect modifiers, with implications for neuroinflammatory biomarker-guided anxiety prevention strategies.MethodsUsing cross-sectional data from 30,418 adults undergoing routine health examinations (July 2020–June 2021), anxiety severity was assessed via the Self-Rating Anxiety Scale (SAS; score ≥ 50 as clinically relevant). Plasma MPO was quantified by ELISA. Multivariate logistic regression, restricted cubic splines (RCS), threshold effect analysis, and subgroup interactions were conducted to evaluate nonlinear associations.ResultsA U-shaped relationship between MPO and anxiety risk was identified. In fully adjusted models, participants in the lowest (Q1: ≤29.77 ng/mL, OR = 1.15, 95% CI: 1.03–1.28, p = 0.01) and highest quintiles (Q5: ≥47.3 ng/mL, OR = 1.17, 95% CI: 1.05–1.31, p = 0.004) exhibited significantly elevated anxiety risks compared to the reference quintile (Q2: 29.8–34.7 ng/mL). RCS analysis confirmed a nonlinear association (p for nonlinearity < 0.01), with an inflection point at 30 ng/mL: below this threshold, each 1 ng/mL MPO increase reduced anxiety risk (OR = 0.982, CI: 0.970–0.994), while levels above it heightened risk (OR = 1.004, CI: 1.001–1.008). Diabetes mellitus significantly modified this relationship (p-interaction = 0.028), with diabetic individuals showing amplified risks at higher plasma MPO (Q5 OR = 1.84 vs. non-diabetic Q5 OR = 1.15).ConclusionPlasma MPO demonstrates a U-shaped association with anxiety risk independent of cardiometabolic confounders. Diabetic individuals exhibit heightened susceptibility to MPO-related anxiety, suggesting synergistic neuroinflammatory pathways. Monitoring MPO may aid in risk stratification and personalized interventions, particularly in populations with diabetes.