Date Published: April 18, 2017
Publisher: Public Library of Science
Author(s): Jalal Poorolajal, Fatemeh Zeraati, Ali Reza Soltanian, Vida Sheikh, Elham Hooshmand, Akram Maleki, Yan Li.
Increased dietary potassium intake is thought to be associated with low blood pressure (BP). Whether potassium supplementation may be used as an antihypertensive agent is a question that should be answered.
To assess the effect of oral potassium supplementation on blood pressure in patients with primary hypertension.
We searched Medline, Web of Science, Scopus, Cochrane Central Register of Controlled Trials until October 2016. We also screened reference lists of articles and previous reviews. We applied no language restrictions.
We included randomized placebo-controlled clinical trials addressing the effect of potassium supplementation on primary hypertension for a minimum of 4 weeks.
We extracted data on systolic and diastolic BP (SBP and DBP) at the final follow-up. We explored the heterogeneity across studies using Cochran’s test and I2 statistic and assessed the probability of publication bias using Begg’s and Egger’s tests. We reported the mean difference (MD) of SBP and DBP in a random-effects model.
We found a total of 9059 articles and included 23 trials with 1213 participants. Compared to placebo, potassium supplementation resulted in modest but significant reductions in both SBP (MD -4.25 mmHg; 95% CI: -5.96 to -2.53; I2 = 41%) and DBP (MD -2.53 mmHg; 95% CI: -4.05 to -1.02; I2 = 65%). According to the change-score analysis, based on 8 out of 23 trials, compared to baseline, the mean changes in SBP (MD -8.89 mmHg; 95% CI: -13.67 to -4.11) and DBP (MD -6.42 mmHg; 95% CI: -10.99 to -1.84) was significantly higher in the intervention group than the control group.
Our findings indicated that potassium supplementation is a safe medication with no important adverse effects that has a modest but significant impact BP and may be recommended as an adjuvant antihypertensive agent for patients with essential hypertension.
Evidence has shown that high potassium intake can reduce blood pressure (BP), decrease the risk of developing cardiovascular disease, and mitigate the adverse effects of salt on blood pressure . The World Health Organization (WHO) recommends a potassium intake of at least 90 mmol/day (3.5 g/day) from food for adults to reduce BP and risk of cardiovascular disease, cerebrovascular events, and coronary heart disease. Current evidence has shown no significant difference between the flavor and taste of potassium-enriched salt and regular salt . The WHO also recommends a potassium intake of at least 90 mmol/day from food for children to control BP . However, there is no need to give a supplement or specially formulated products because most people can replace needed potassium through food consumption [4,5].
The Vice-chancellor of Research and Technology, Hamadan University of Medical Sciences, approved and funded this review. We wrote the report based on the PRISMA checklist of items for reporting systematic reviews and meta-analyses . The supporting PRISMA checklist of this review is available as supporting information; see S1 PRISMA Checklist.
Our findings indicated that potassium supplementation had a statistically significant effect on both SBP and DBP. Subgroup analyses revealed an evidence of dose-response relationship between potassium intake and BP reduction. Accordingly, potassium supplementation had a clinically modest impact on essential hypertension and thus may be used as an adjuvant antihypertensive agent.
This meta-analysis provided evidence based on RCTs of the effect of potassium intake on BP in hypertensive patients. Our findings indicated that potassium supplementation is a safe medication with no important adverse effects that has a modest but significant impact BP and may be recommended as an adjuvant antihypertensive agent for patients with essential hypertension.