原发性高血压患者盐敏感性的影响因素和急性盐负荷后血压及钠钾代谢的变化

Influence factors of salt-sensitive hypertension and responses of blood pressure and urinary sodium and potassium excretion to acute oral saline loading among essential hypertensive patients

目的探讨原发性高血压患者血压盐敏感性的影响因素和急性盐负荷后血压水平及钠钾代谢的变化情况。方法通过整群随机抽样，选取北京市金盏第二社区的原发性高血压患者作为研究对象。采用改良的Sullivan急性口服盐水负荷及呋塞米排钠缩容试验进行盐敏感性判定，采用二分类logistic回归分析血压盐敏感性的影响因素，并观察血压、尿钠和尿钾浓度的变化情况。结果在342例原发性高血压患者中，共检出盐敏感者63例（18．4％）。盐敏感者年龄大于非盐敏感者（P〈0．05）。二分类logistic回归分析显示，年龄（OR=1．744，95％CI：0．922—3．300，P〉0．05）、性别（OR=0．728，95％CI：0．374～1．415，P〉0．05）、总胆固醇水平（OR=1．168，95％CI：0．882—1．547，P〉0．05）和24h尿钠量（OR=0．998，95％CI：0．995～1．002，P〉0．05）均不是原发性高血压患者血压盐敏感性的影响因素。两因素重复测量方差分析显示：患者的血压、尿钠及尿钾浓度在基线、急性盐负荷后2h和呋塞米排钠缩容后2h之间的差异均有统计学意义（P均〈0．01）；在急性盐负荷后2h和呋塞米排钠缩容后2h，盐敏感者的血压均高于非盐敏感者（P均〈0．01），而尿钠和尿钾浓度差异均无统计学意义（P均〉0．05）。结论年龄、性别、总胆固醇水平和24h尿钠量均不是原发性高血压患者血压盐敏感性的影响因素。急性盐水负荷及利尿排钠缩容后，盐敏感性原发性高血压患者表现出“压力性利钠”功能异常。

Objective To explore the influence factors of salt-sensitive hypertension and to observe changes of blood pressures and urinary sodium and potassium excretion in response to acute oral saline loading among essential hypertensive patients in China. Methods Essential hypertensive patients from Beijing Jinzhan second community were included in this study. Salt-sensitivity was determined via the improved Sullivan＇ s aeute oral saline loading and furosemide volume-depletion tests. Binary logistic regression analysis was applied to explore influence factors of salt-sensitive hypertension. Acute oral saline loading induced changes on blood pressures and urinary sodium and potassium excretion were observed. Results Sixty-three salt-sensitive hypertensive patients were classified out of a total of 342 （ 18. 4% ） essential hypertensive patients. Salt-sensitive patients were elder than the non-salt-sensitive patients （P 〈 0. 05）. Binary logistic regression analysis showed that age （ OR = 1. 744,95% CI： 0. 922 - 3. 300, P 〉0. 05）, gender（ OR = 0. 728, 95% CI： 0. 374 - 1. 415, P 〉 0. 05 ）, total cholesterol level （ OR = 1. 168, 95% CI：0. 882 - 1. 547,P 〉 0. 05 ） and 24-hour urinary sodium （ OR =0. 998,95% CI：0. 995 - 1. 002, P 〉 0. 05 ） were not influencing factors of salt-sensitivity among essential hypertensive patients. Bivariate general linear models for repeated measures showed that there were significant statistical differences on blood pressures and urinary electrolytes concentrations between the beginning of trials, 2 hours after acute saline loading and 2 hours after furosemide volume-depletion（ all P 〈0. 01 ）. There was a greater blood pressures change in salt-sensitive patients than in non-salt-sensitive patients （ all P 〈 0. 01 ） while urinary electrolytes concentrations change was similar between two groups （ all P 〉 0. 05 ）. Conclusions Age, gender, total cholesterol level and 24-hour urinary sodium are not influencing factors of salt-sensitivity among essential hypertensive patients in this study. Impaired pressure natriuresis during acute oral saline loading and furosemide volume-depletion tests is presented in salt-sensitive essential hypertensive patients.