Whelton P K, He J, Cutler J A, Brancati F L, Appel L J, Follmann D, Klag M J
Welch Center for Prevention, Epidemiology and Clinical Research, The Johns Hopkins University School of Hygiene and Public Health, Baltimore, Md, USA.
JAMA. 1997 May 28;277(20):1624-32. doi: 10.1001/jama.1997.03540440058033.
To assess the effects of supplementation with oral potassium on blood pressure in humans.
Meta-analysis of randomized controlled trials.
English-language articles published before July 1995.
Thirty-three randomized controlled trials (2609 participants) in which potassium supplementation was the only difference between the intervention and control conditions.
Using a standardized protocol, 2 of us independently abstracted information on sample size, duration, study design, potassium dose, participant characteristics, and treatment results.
By means of a random-effects model, findings from individual trials were pooled, after results for each trial were weighted by the inverse of its variance. An extreme effect of potassium in lowering blood pressure was noted in 1 trial. After exclusion of this trial, potassium supplementation was associated with a significant reduction in mean (95% confidence interval) systolic and diastolic blood pressure of -3.11 mm Hg (-1.91 to -4.31 mm Hg) and -1.97 mm Hg (-0.52 to -3.42 mm Hg), respectively. Effects of treatment appeared to be enhanced in studies in which participants were concurrently exposed to a high intake of sodium.
Our results support the premise that low potassium intake may play an important role in the genesis of high blood pressure. Increased potassium intake should be considered as a recommendation for prevention and treatment of hypertension, especially in those who are unable to reduce their intake of sodium.
评估口服补钾对人体血压的影响。
随机对照试验的荟萃分析。
1995年7月以前发表的英文文章。
33项随机对照试验（2609名参与者），其中补钾是干预组和对照组之间的唯一差异。
我们两人使用标准化方案，独立提取了关于样本量、持续时间、研究设计、钾剂量、参与者特征和治疗结果的信息。
采用随机效应模型，在对每个试验的结果按其方差的倒数加权后，汇总了各个试验的结果。在1项试验中发现钾对降低血压有极端效果。排除该试验后，补钾与收缩压和舒张压的显著降低相关，平均（95%置信区间）收缩压降低-3.11 mmHg（-1.91至-4.31 mmHg），舒张压降低-1.97 mmHg（-0.52至-3.42 mmHg）。在参与者同时摄入高钠的研究中，治疗效果似乎有所增强。
我们的结果支持低钾摄入可能在高血压发病中起重要作用这一前提。应考虑增加钾的摄入量，作为预防和治疗高血压的建议，尤其是在那些无法减少钠摄入量的人群中。
