Intervention Review

Potassium supplementation for the management of primary hypertension in adults

  1. Heather O Dickinson1,*,
  2. Donald Nicolson2,
  3. Fiona Campbell3,
  4. Fiona R Beyer4,
  5. James Mason5

Editorial Group: Cochrane Hypertension Group

Published Online: 19 JUL 2006

Assessed as up-to-date: 31 MAR 2006

DOI: 10.1002/14651858.CD004641.pub2


How to Cite

Dickinson HO, Nicolson D, Campbell F, Beyer FR, Mason J. Potassium supplementation for the management of primary hypertension in adults. Cochrane Database of Systematic Reviews 2006, Issue 3. Art. No.: CD004641. DOI: 10.1002/14651858.CD004641.pub2.

Author Information

  1. 1

    Newcastle University, Institute of Health and Society, Newcastle upon Tyne, Tyne & Wear, UK

  2. 2

    University of Leeds, School of Healthcare, Leeds, UK

  3. 3

    University of Sheffield, School of Health and Related Research, Sheffield, UK

  4. 4

    University of Newcastle, Institute for Health and Society, Newcastle upon Tyne, Tyne & Wear, UK

  5. 5

    Durham University, Queen's Campus, School of Medicine and Health, Stockton-on-Tees, UK

*Heather O Dickinson, Institute of Health and Society, Newcastle University, 21 Claremont Place, Newcastle upon Tyne, Tyne & Wear, NE2 4AA, UK. heather.dickinson@newcastle.ac.uk.

Publication History

  1. Publication Status: Edited (no change to conclusions)
  2. Published Online: 19 JUL 2006

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Abstract

  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要

Background

Epidemiological evidence on the effects of potassium on blood pressure is inconsistent.

Objectives

To evaluate the effects of potassium supplementation on health outcomes and blood pressure in people with elevated blood pressure.

Search methods

We searched the Cochrane Library, MEDLINE, EMBASE, Science Citation Index, ISI Proceedings, ClinicalTrials.gov, Current Controlled Trials, CAB abstracts, and reference lists of systematic reviews, meta-analyses and randomised controlled trials (RCTs) included in the review.

Selection criteria

Inclusion criteria were: 1) RCTs of a parallel or crossover design comparing oral potassium supplements with placebo, no treatment, or usual care; 2) treatment and follow-up >=8 weeks; 3) participants over 18 years, with raised systolic blood pressure (SBP) >=140 mmHg or diastolic blood pressure (DBP) >=85 mmHg); 4) SBP and DBP reported at end of follow-up. We excluded trials where: participants were pregnant; received antihypertensive medication which changed during the study; or potassium supplementation was combined with other interventions.

Data collection and analysis

Two reviewers independently extracted data and assessed trial quality. Disagreements were resolved by discussion or a third reviewer. Random effects meta-analyses and sensitivity analyses were conducted.

Main results

Six RCT's (n=483), with 8-16 weeks follow-up, met our inclusion criteria. Meta-analysis of five trials (n=425) with adequate data indicated that potassium supplementation compared to control resulted in a large but statistically non-significant reductions in SBP (mean difference: -11.2, 95% CI: -25.2 to 2.7) and DBP (mean difference: -5.0, 95% CI: -12.5 to 2.4). The substantial heterogeneity between trials was not explained by potassium dose, quality of trials or baseline blood pressure.

Excluding one trial in an African population with very high baseline blood pressure resulted in smaller overall reductions in blood pressure (SBP mean difference: -3.9, 95% CI: -8.6 to 0.8; DBP mean difference: -1.5, 95% CI: -6.2 to 3.1). Further sensitivity analysis restricted to two high quality trials (n=138) also found non-significant reductions in blood pressure (SBP mean difference: -7.1, 95% CI: -19.9 to 5.7; DBP mean difference: -5.5, 95% CI: -14.5 to 3.5).

Authors' conclusions

Potassium supplementation has no statistically significant effect on blood pressure. Due to small number of participants in the two high quality trials, the short duration of follow-up, and the unexplained heterogeneity between trials, the evidence about the effect of potassium supplementation on blood pressure is not conclusive. Further high quality RCTs of longer duration are required to clarify whether potassium supplementation can reduce blood pressure and improve health outcomes.

 

Plain language summary

  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要

Oral potassium supplementation for high blood pressure in adults

This review examines whether taking potassium supplements can be recommended for treating adults with high blood pressure from no known cause. The results of the trials varied a lot: some trials found potassium lowered blood pressure much more than a dummy drug (placebo), while others found little difference between potassium and placebo. Overall no significant reduction in blood pressure from taking potassium supplements was found.

Most included trials were of poor quality, so their results may not be reliable. The trials were not long enough or large enough to measure whether potassium supplements reduce the risk of death, heart attack or stroke, which may be caused by high blood pressure. The studies reporting adverse effects did not find any serious side effects from taking potassium supplements.

This review does not confirm whether potassium supplements can lower high blood pressure and therefore does not recommend them for treating hypertension. More trials enrolling a large number of participants with long periods of follow-up are necessary to know whether or not potassium supplements can lower high blood pressure.

 

摘要

  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要

背景

「補充鉀離子」應用於成人原發性高血壓治療的角色

目前在流行病學方面,鉀離子在調控血壓的部份,仍沒有一個一致性的結論。

目標

評估「補充鉀離子」應用於高血壓者血壓調控及健康的成效

搜尋策略

我們搜尋了Cochrane Library, MEDLINE, EMBASE, Science Citation Index, ISI Proceedings, ClinicalTrials.gov, Current Controlled Trials, CAB abstracts以上這些資料庫,並參考了許多系統性回顧研究、多項研究綜合分析研究、隨機對照試驗研究的文獻資料。

選擇標準

入選條件包括:(1)比較「口服鉀離子補充」及「安慰劑、無治療、或一般照護」的隨機對照試驗研究。(2)治療及追蹤大於八個星期。(3) 參加試驗者年滿18歲,且合併收縮壓大於140mmHg,或舒張壓大於85mmHg。(4)追蹤結束時有紀錄收縮壓及舒張壓。我們排除了以下的研究:參加試驗者懷有身孕、研究期間調整過高血壓用藥、除了鉀離子補充外還有使用其他的治療方法。

資料收集與分析

由二位專家獨立檢閱及評估這些研究資料,若遇到不同意見時,則經由彼此討論或第三位專家的意見來解決。這些研究資料再進一步進行隨機綜合分析研究及敏感度分析。

主要結論

總共有6個隨機對照試驗研究(包含了483位參加試驗者)符合我們的入選條件,追蹤時間為8到26個星期。5個統合分析(包含了425位參加試驗者)顯示「鉀離子補充」的參加試驗者比較對照組並沒有明顯的降低收縮壓(平均差: −11.2 mmHg, 95%信賴區間: −25.2 to 2.7)及降低舒張壓(平均差: −11.2 mmHg, 95%信賴區間: −25.2 to 2.7)。無法使用「鉀離子劑量」、「研究的品質」或「血壓基準值」來解釋這些研究間的異質性。但有一組「非洲族群併極高基準血壓值」試驗例外,此試驗結果發現總體血壓有些許下降.(收縮壓平均差: −3.9 mmHg, 95%信賴區間: −8.6 to 0.8; 舒張壓平均差: −1.5 mmHg, 95%信賴區間: −6.2 to 3.1). 有2個高品質研究(n = 138)的敏感度分析中也發現沒有明顯的降低血壓.(收縮壓平均差: −7.1 mmHg, 95%信賴區間: −19.9 to 5.7; 舒張壓平均差: −5.5 mmHg, 95%信賴區間: −14.5 to 3.5).

作者結論

這個系統性的回顧發現鉀離子補充對於血壓的調控並沒有統計上的成效。由於2個高品質研究的參加試驗者人數過少,追蹤的時間過短,研究間無法解釋的異質性,因此鉀離子補充對於血壓調控的成效並沒有結論。未來我們需要更多設計良好,追蹤時間更長的隨機對照試驗研究來釐清鉀離子補充是否可降低血壓及促進健康。

翻譯人

本摘要由臺北榮民總醫院李培雯翻譯。

此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。

總結

這篇回顧文章是用來檢視「口服鉀離子補充」能否被推薦用來治療成人高血壓。這些研究結果差異很大:有些認為「鉀離子補充」有降低血壓的效果,有些二者差異不大。總體而言,鉀離子補充並無法顯著降低血壓。這些研究大多設計不良,所以這個解論並不值得信賴。這些研究大多不夠長久也不夠大型來評估鉀離子補充是否可降低因高血壓造成死亡,心臟病發及中風的風險。並沒有研究指出鉀離子補充有嚴重的副作用。這篇回顧並沒有證實鉀離子補充可降低血壓,因此不被用來推薦治療高血壓。需要更多包含眾多參加試驗者,追蹤時間更長的隨機對照試驗研究來瞭解鉀離子補充是否可降低血壓。