CORRELATION ANALYSIS BETWEEN VASCULAR OVERLOAD INDEX AND LEFT VENTRICULAR HYPERTROPHY IN HYPERTENSION

Abstract

Objective: The vascular overload index (VOI) is commonly used to assess the’overload’phenomenon induced by hypertension,and vascular overload is one of the pathogenic mechanisms for left ventricular hypertrophy(LVH)associated with hypertension. The left ventricular mass index (LVMI) is the most frequently used diagnostic indicator for LVH. Research has found that VOI derived from office blood pressure readings is correlated with LVH,but it doesn’t evaluate the relationship between vascular load during different periods of the day and LVH. This study aims to investigate the correlation between VOI obtained from 24-hour ambulatory blood pressure and LVH. Design and method: A total of 591 hypertensive patients hospitalized from July 2020 to July 2022 were included. Echocardiography was performed in each patient,and the LVMI was calculated; The 24-hour VOI(VOI24h=1.33×SBP24h-0.33×DBP24h-133.3mmHg),daytime VOI(VOId),and nighttime VOI(VOIn)were calculated based on the 24-hour ambulatory blood pressure results. A multivariate logistic regression was utilized to explore the correlation between VOI at different times and LVH,adjusting for covariates such as gender,age,BMI,triglycerides,cholesterol,HDLand LDL. Results: The age of the 591 hypertensive patients was 63.8±13.3years and BMI was 25.7±3.6Kg/m2.Univariate linear regression analysis showed that VOI24h,VOId,and VOIn were positively correlated with LVMI(P<0.001). After adjusting,all of VOI remained correlated with LVMI. Compared with the lowest tertile of VOI24h, the highest tertile had β (95%CI) of 9.25(6.09∼12.4). For VOId,the highest tertile compared to the lowest had β (95%CI) of 8.70(5.55∼11.86),and for VOIn,it was 9.48(6.32∼12.64).Univariate logistic regression analysis indicated that all of VOI were significantly associated with LVH(P<0.001),and after adjusting for confounders,all of VOI still correlated with LVH,with OR(95%CI)respectively being 1.04(1.02∼1.07),1.04(1.02∼1.07),and 1.03(1.01∼1.05). Subgroup analysis revealed that regardless of the comorbidity of the hypertensive patients,all of VOI were all related to LVH.However, when analyzed by season,VOI24h and VOId were significantly associated with LVH in summer and winter, but not in spring and autumn; VOIn was only associated with LVH in winter. Conclusions: In the hypertensive patients,VOI derived from 24-hour ambulatory blood pressure is significantly correlated with LVH. Compared to spring and autumn,vascular load during summer and winter is significantly associated with LVH. Therefore,not only should steady blood pressure control over 24 hours be emphasized,but also pay attention to the impact of vascular load on LVH during summer and winter.