Brachial flow-mediated dilation predicts subclinical target organ damage progression in essential hypertensive patients: a 3-year follow-up study

Objectives: We found impaired brachial flow-mediated dilation (FMD) was associated with the number of target organ damage (TOD) in 2007. The present study investigated whether FMD predicted TOD progression in essential hypertension. Methods and results: Endothelium-dependent FMD was measured in 280 adults in 2007. At the third year of examination, 199 patients (mean age 62.5 +/- 9.5, men 59.3%) were approached for participation in our study. Patients were divided into two groups: normal FMD group (FMD >= 10) and impaired FMD group (FMD < 10). In patients with 0-1 TOD at baseline, impaired FMD group (n = 65) led to thicker intima-media thickness (P = 0.02), increased carotid-to-femoral pulse wave velocity (P = 0.03), increased urinary albumin/creatinine ratio (P = 0.04) and increased TOD number (P = 0.02), as compared with the normal FMD group (n = 59) at the end of the follow-up, even after adjusting for age and sex, whereas the relationship did not exist in 2-4 TOD group at baseline. TOD number increase was associated with the prevalence of diabetes mellitus (beta = 0.180, P = 0.035), blood pressure control (beta = -0.277, P = 0.001), low-density lipoprotein cholesterol (beta = 0.234, P = 0.006) and baseline FMD (beta = -0.168, P = 0.043) in stepwise multivariate regression analysis. FMD remained a significant predictor of TOD number increase in multiple logistic regression analysis after adjustment for several known risk factors (relative risk 0.92, 95% confidence interval 0.85-0.99, P = 0.042, for each 1% increase in FMD). Conclusion: FMD is a predictor of future TOD progression in low-risk essential hypertensive patients, but has little predictive value in the late stage of TOD.