Age and gender-specific flow-mediated dilation reference values and predictive factors for Chinese children and adolescents.

Background: We aim to establish normative reference values of brachial artery flow-mediated dilation (FMD) by age and gender in children and adolescents, and to identify predictors of FMD in this population.

Methods: A representative sample of 1498 healthy children and adolescents aged 8 to 17 years was recruited. Subjects underwent sonographic brachial artery assessment and blood sampling. Smoothed gender-specific FMD percentile curves were constructed using the Lambda-Mu-Sigma (LMS) method. Predictive factors of FMD were identified using linear regression analysis.

Results: Mean FMD among children and adolescents in the community setting was 8.57 ± 0.90%. Smoothed gender-specific FMD in centiles were constructed as a reference benchmark. Regression analysis after adjustment for age, gender, body mass index (BMI) z-score, and baseline artery diameter, when applicable, demonstrated that FMD is positively correlated with age (β = 0.142, p < 0.001, 95% CI [0.081-0.203]) and high density lipoprotein (HDL) (β = 0.103, p = 0.001, 95% CI [0.041-0.165]), while negatively correlated with baseline artery diameter (β = -0.117, p = 0.001, 95% CI [-0.189 - -0.046]), diastolic blood pressure (DBP) (β = -0.053, p = 0.047, 95% CI [-0.105 - -0.001]), glucose (β = -0.091, p = 0.004, 95% CI [-0.153 - -0.030]) and triglyceride (TG) (β = -0.138, p < 0.001, 95% CI [-0.198 - -0.078]). Multivariate regression analysis showed that age, baseline artery diameter, DBP, glucose and TG were independent predictors of FMD.

Conclusions: Normative reference values for FMD were constructed with predictive factors identified for children and adolescents.