Chest:限盐饮食或可缓解睡眠呼吸暂停

　　澳大利亚昆士兰大学医学院Pimenta及其同事进行的一项研究表明，对于顽固性高血压和醛固酮增多症患者，膳食中盐的摄入量与其阻塞性睡眠呼吸暂停（OSA）严重程度有关。

　　OSA是高血压病（尤其是顽固性高血压病）与心血管疾病较强的独立危险因素，顽固性高血压患者的OSA患病率普遍较高，这一现象与此类患者醛固酮水平、盐摄入量以及血压的盐敏感性较高有关。

　　研究者使用夜间多导睡眠仪监测、24小时尿钠排泄量（UNa）、以及醛固酮水平等指标，对97例摄入其平常饮食的顽固性高血压患者进行了前瞻性评估。所有受试者平均诊所血压（BP）为156.3±22.4 / 88.9±13.3mmHg，平均使用4.3±1.1种降压药物，OSA发生率为77.3%。28例（28.9%）患者被诊断为醛固酮增多症。只有在醛固酮增多症患者中，UNa水平才是预测患者OSA严重程度的独立预测因子。

　　研究者认为，该结果支持可将限盐饮食作为减轻此类患者阻塞性睡眠呼吸暂停严重程度的一种治疗策略。 

INCREASED DIETARY SODIUM IS RELATED TO SEVERITY OF OBSTRUCTIVE SLEEP APNEA IN PATIENTS WITH RESISTANT HYPERTENSION AND HYPERALDOSTERONISM

Background:  Obstructive sleep apnea (OSA) is a strong and independent risk factor for the development of hypertension, particularly resistant hypertension, and cardiovascular diseases. Patients with resistant hypertension have a high prevalence of OSA in association with elevated aldosterone levels, high salt intake, and salt-sensitivity of blood pressure.

Objectives:  Determine if dietary salt and aldosterone are associated with severity of OSA in patients with resistant hypertension.

Methods:  Ninety-seven patients with resistant hypertension were prospectively evaluated by overnight polysomnography and 24-hour urinary sodium excretion (UNa) and aldosterone while ingesting their usual diet. Hyperaldosteronism was defined as PRA < 1 ng/mL/hr and UAldo ≥ 12 µg/24-hr.

Results:  Overall, the mean clinic blood pressure (BP) was 156.3±22.4/88.9±13.3 mm Hg on an average 4.3±1.1 antihypertensive medications. Prevalence of OSA was 77.3%. Twenty-eight (28.9%) of patients were diagnosed with hyperaldosteronism. UNa was an independent predictor of severity of OSA only in patients with hyperaldosteronism.

Conclusions:  The current findings suggest that dietary salt is related to the severity of OSA in patients with resistant hypertension and hyperaldosteronism. Our results support dietary salt restriction as a treatment strategy for reduction of OSA severity in these patients.