Left ventricular diastolic function dysfunction and its related risk factors in older adults: Guangzhou Biobank Cohort Study - CVD

Abstract

目的探讨广州市相对健康的中老年人左心室舒张功能减退及其相关危险因素。方法采用单纯随机方法收集390名年龄≥50岁,无脑卒中、心肌梗死、肺心病及恶性肿瘤等重大慢性疾病史的中老年人进行横断面研究，收集其个人资料及病史、体格检查并测定血清空腹血糖、血脂水平；采用彩色多普勒超声诊断仪,进行左心舒张功能指标测定，包括二尖瓣舒张早期血流峰值（E）和舒张晚期血流峰值（A）及E/A,E峰减速时间(DT)和等容舒张时间（IVRT）。结果①A峰随着年龄的增长而增高，E/A随着年龄的增长而减低（均P<0.05）。②调整了年龄和性别之后，随着腰围的增大，A峰和IVRT随之升高，而E/A则随之降低；同时也发现A峰随三酰甘油和空腹血糖水平升高而升高(均P<0.05)。③用三分位数分组，对310名未服用抗高血压药物者的血压水平，调整了年龄和性别，结果显示A峰随收缩压和脉压差升高而增高（P<0.05），而E/A则随收缩压和舒张压的升高而降低（P<0.05）。④理想血压组、正常血压高值组和高血压组的A峰水平呈逐步升高(P<0.05)，而E/A则呈逐步下降的趋势 (P<0.05)。结论血压升高是左心室舒张功能损伤的独立危险因素，即使血压在正常水平范围内, 左心舒张功能仍随血压的升高而减低。 Objective: To study left ventricular diastolic function and it s risk factors in relatively healthy older people in Guangzhou. Methods: A cross-sectional investigation was performed in a random sample , from the Guangzhou Biobank Cohort Study , of 390 individuals aged 50 years or above and without apparent diseases including stroke , myocardial infarction , COPD and cancers. Personal history , blood pressure , fasting glucose and lipids were assessed. Color Doppler ultrasound was used to measure indicators of left ventricular diastolic function , including peak E velocity and peak A velocity of mitral diastolic flow ( E) and (A) , E/ A ratio , the deceleration time of peak E(DT) , and isovolumic relaxation time ( IVRT) . Results: ①With increasing age , peak A significantly increased and E/ A level significantly decreased (all P < 0. 05). ②After adjusting age and sex , A and IVRT increased , while E/ A decreased with waist circumference. Moreover , A increased with triglyceride and fasting plasma glucose (all P < 0. 05) . ③After adjusting age and sex , A was positively associated with systolic and diastolic blood pressure (all P < 0. 05) , while E/ A was negatively associated with systolic and diastolic blood pressure in tertiles in 310 individuals without antihypertensive medication (all P < 0. 05) . ④There was a t rend of increase in A ( P < 0. 05) and decrease in E/ A ( P < 0. 05) from optimal to normal blood pressure to hypertension. Conclusions: Higher blood pressure was an independent risk factor for left ventricular diastolic dysfunction. Even within normal blood pressure level , left ventricular diastolic function may deteriorate with increased blood pressure.