Cutler J A, Follmann D, Allender P S
Division of Epidemiology and Clinical Applications, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
Am J Clin Nutr. 1997 Feb;65(2 Suppl):643S-651S. doi: 10.1093/ajcn/65.2.643S.
We updated a previously published overview of randomized clinical trials testing the effects of reducing sodium intake. We excluded trials that had confounded designs, enrolled preadolescent study populations, tested intakes outside the usual range for the US population, or reported neither systolic nor diastolic blood pressure. Thirty-two trials with outcome data for 2635 subjects were included. Two reviewers abstracted information independently and differences were reconciled. Pooled blood pressure differences between treated and control groups were highly significant for all trials combined and for trials in hypertensive and normotensive subjects pooled separately. The effects on blood pressure of lowering sodium in hypertensive and normotensive subjects, respectively (each trial weighted according to sample size), were -4.8/-2.5 and -1.9/-1.1 mm Hg (systolic/diastolic). Median differences in sodium excretion between sodium-reduction and control groups in these subgroups were -77 and -76 mmol/24 h, respectively. Weighted linear-regression analyses across the trials showed dose responses, which were more consistent for trials in normotensive subjects. These associations were, per 100 mmol Na/24 h, -5.8/-2.5 and -2.3/-1.4 mm Hg in hypertensive and normotensive subjects, respectively. There is no evidence that sodium reduction as achieved in these trials presents any safety hazards. The blood pressure reduction that would result from a substantial lowering of dietary sodium in the US population could reduce cardiovascular morbidity and mortality.
我们更新了之前发表的关于测试降低钠摄入量效果的随机临床试验综述。我们排除了设计存在混淆、纳入青春期前研究人群、测试美国人群通常范围之外的摄入量或既未报告收缩压也未报告舒张压的试验。纳入了32项试验，这些试验有2635名受试者的结局数据。两名评审员独立提取信息并解决分歧。治疗组和对照组之间的合并血压差异在所有合并试验以及分别合并的高血压和正常血压受试者试验中均具有高度显著性。降低钠摄入量对高血压和正常血压受试者血压的影响（每项试验根据样本量加权）分别为-4.8/-2.5和-1.9/-1.1毫米汞柱（收缩压/舒张压）。这些亚组中钠减少组和对照组之间钠排泄的中位数差异分别为-77和-76毫摩尔/24小时。对所有试验进行加权线性回归分析显示出剂量反应，在正常血压受试者的试验中更为一致。这些关联在高血压和正常血压受试者中，每100毫摩尔钠/24小时分别为-5.8/-2.5和-2.3/-1.4毫米汞柱。没有证据表明这些试验中实现的钠减少存在任何安全隐患。美国人群饮食中钠的大幅降低所导致的血压降低可减少心血管疾病的发病率和死亡率。
