Relationship Between Vascular Overload Index And Cardiovascular Structure And Function In Hypertensives

Objectives:The aim of this study was to investigate the relationship between vascular overloadindex (VOI) and cardiovascular structure and function, which were evaluated byendothelium-dependent vasodilatation (FMD) of brachial artery (BA), intima mediathickness of carotid artery (CA-IMT), left ventricular mass index (LVMI).Methods:744subjects, including646with essential hypertension (EH) and98with normalblood pressure, were enrolled between August2000and March2013. Before themeasuring of FMD, patients’ height, body weight, heart rate, systolic blood pressure(SBP), diastolic blood pressure(DBP) were recorded. Fasting blood glucose, bloodlipid profile, liver and renal functions, routine blood test and fibrinogen were alsodetermined. All patients underwent echocardiographic exam to detect LVMI. Thedilatation of brachial artery induced by reactive hyperemia was examined byhigh-resolution vascular ultrasound. The intima media thickness of bilateral carotidartery was also measured. CA-IMT was defined as1.5mm with any presence ofplaque on either side of carotid artery. Based on the diagnostic cutpoint of CA-IMT≥1.0mm, EH patients were divided into two groups: IMT<1.0mm group (n=376) andIMT≥1.0mm group (n=270). Subjects with normal blood pressure served as thecontrol（n=98）. VOI=1.33×SBP-0.33×DBP-133.3mmHg.Results:1. Of744subjects,428were male,316were female, with an average age of61.14±12.26years. Stepwise multiple regression analysis showed that VOI was aninfluencing factor for FMD, CA-IMT and LVMI. For an increase of10mmHg of VOI,FMD was correspondingly decreased by0.45%, CA-IMT was thicken by0.046mm,and LVMI was increased by2.04g/m2. 2. Of646EH patients, aged62.08±12.28years,386were male,260were female.Stepwise multiple regression analysis showed that VOI was a determinant factor forFMD, CA-IMT and LVMI in EH patients. For an increase of10mmHg of VOI, FMDwas decreased by0.47%, CA-IMT was thicken by0.045mm, and LVMI wasincreased by1.40g/m2.3. For EH patients <70years old, VOI was an influencing factor for FMD and LVMI.The correlations were not significant when EH patients were over70years old. Afterstratification of age, VOI was found to be a persistent influencing factor for CA-IMT.4. For EH patients with≤3risk factors, VOI was an influencing factor for FMD. Thecorrelation was not significant for EH patients with over3risk factors. Irrespective ofnumbers of risk factors, VOI was a persistent influencing factor for CA-IMT.Conclusion:VOI was an influencing factor for FMD, CA-IMT and LVMI. With the increase of ageor risk factor, the influences of VOI on FMD and LVMI were weakened in EHpatients. VOI was an independent influencing factor for CA-IMT in EH patients.