The Johns Hopkins University School of Medicine, The Johns Hopkins Bloomberg School of Public Health, and The Welch Center for Prevention, Epidemiology and Clinical Research, Baltimore, Maryland.
Division of General Medicine and Primary Care, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.
J Clin Hypertens (Greenwich). 2019 Mar;21(3):355-362. doi: 10.1111/jch.13487. Epub 2019 Jan 28.
Lightheadedness after standing contributes to adverse clinical events, including falls. Recommendations for higher sodium intake to treat postural lightheadedness have not been evaluated in a trial setting. The Dietary Approaches to Stop Hypertension (DASH)-Sodium trial (1998-1999) tested the effects of the DASH diet and sodium reduction on blood pressure (BP). Participants were randomly assigned to DASH or a typical Western diet (control). During either diet, participants ate three sodium levels (50, 100, 150 meq/d at 2100 kcal) in random order for 30-days, separated by 5-day breaks. Participants reported the presence and severity of postural lightheadedness at baseline and after each feeding period. There were 412 participants (mean age 48 years; 57% women; 57% black). Mean baseline SBP/DBP was 135/86 mm Hg; 9.5% reported baseline lightheadedness. Among those consuming the DASH diet, high vs low sodium increased lightheadedness (OR 1.71; 95% CI: 1.01, 2.90; P = 0.047) and severity of lightheadedness (P = 0.02), but did not affect lightheadedness in those consuming the control diet (OR 0.77; 95% CI: 0.46, 1.29; P = 0.32). Among those consuming high vs low sodium in the context of the DASH diet, adults <60 vs ≥60 years old experienced more lightheadedness (P-interaction = 0.04), along with obese vs non-obese adults (P-interaction = 0.01). In the context of the DASH diet, higher sodium intake was associated with more frequent and severe lightheadedness. These findings challenge traditional recommendations to increase sodium intake to prevent lightheadedness.
直立性头晕会导致不良临床事件，包括跌倒。尚未在试验环境中评估增加钠摄入量以治疗直立性头晕的建议。饮食方法阻止高血压（DASH）-钠试验（1998-1999 年）测试了 DASH 饮食和钠减少对血压（BP）的影响。参与者被随机分配到 DASH 饮食或典型的西方饮食（对照组）。在任何一种饮食中，参与者都以随机顺序在 2100 卡路里的情况下食用三种钠水平（50、100、150 meq/d），每种饮食持续 30 天，中间休息 5 天。参与者在基线和每次喂养期后报告直立性头晕的存在和严重程度。共有 412 名参与者（平均年龄 48 岁；57%为女性；57%为黑人）。平均基线 SBP/DBP 为 135/86mmHg；9.5%报告有基线头晕。在食用 DASH 饮食的人群中，高钠与低钠相比会增加头晕（OR 1.71；95%CI：1.01，2.90；P=0.047）和头晕严重程度（P=0.02），但对食用对照组饮食的人群没有影响（OR 0.77；95%CI：0.46，1.29；P=0.32）。在 DASH 饮食的高钠与低钠环境中，<60 岁与≥60 岁的成年人经历更多头晕（P 交互=0.04），以及肥胖与非肥胖成年人（P 交互=0.01）。在 DASH 饮食的背景下，较高的钠摄入量与更频繁和更严重的头晕有关。这些发现挑战了传统的增加钠摄入量以预防头晕的建议。
