B- CRF : Nutritional complications
E- 01 : Primitive hypertension
Daily potassium intake and sodium-to-potassium ratio in the reduction of
blood pressure: a meta-analysis of randomized controlled trials
Binia, Aristeaa; Jaeger, Jonathanb; Hu, Youyoub; Singh, Anuragb; Zimmermann, Dianec
Correspondence to Dr Aristea Binia, Nestlé Research Center, P.O. Box 44, Vers-chez-les-Blanc,
CH-1000 Lausanne 26, Switzerland. Tel: +41 21 785 8278; fax: +41 21 785 8554; e-mail:
aristea.binia@rdls.nestle.com
Journal : Journal of Hypertension
Year: 2015 / Month : August
Volume : 33
Pages : 1509–1520
doi: 10.1097/HJH.0000000000000611
ABSTRACT
Objective
To evaluate the efficacy of daily potassium intake on decreasing blood pressure in non-medicated
normotensive or hypertensive patients, and to determine the relationship between potassium intake,
sodium-to-potassium ratio and reduction in blood pressure.
Design
Mixed-effect meta-analyses and meta-regression models.
Data sources
Medline and the references of previous meta-analyses.
Studies eligibility criteria
Randomized controlled trials with potassium supplementation, with blood pressure as the primary
outcome, in non-medicated patients.
Results
Fifteen randomized controlled trials of potassium supplementation in patients without
antihypertensive medication were selected for the meta-analyses (917 patients). Potassium
supplementation resulted in reduction of SBP by 4.7 mmHg [95% confidence interval (CI) 2.4–7.0]
and DBP by 3.5 mmHg (95% CI 1.3–5.7) in all patients. The effect was found to be greater in
hypertensive patients, with a reduction of SBP by 6.8 mmHg (95% CI 4.3–9.3) and DBP by
4.6 mmHg (95% CI 1.8–7.5). Meta-regression analysis showed that both increased daily potassium
excretion and decreased sodium-to-potassium ratio were associated with blood pressure reduction
(P < 0.05). Increased total daily potassium urinary excretion from 60 to 100 mmol/day and decrease
of sodium-to-potassium ratio were shown to be necessary to explain the estimated effect.
Conclusion
Potassium supplementation is associated with reduction of blood pressure in patients who are not
on antihypertensive medication, and the effect is significant in hypertensive patients. The reduction
in blood pressure significantly correlates with decreased daily urinary sodium-to-potassium ratio and
increased urinary potassium. Patients with elevated blood pressure may benefit from increased
potassium intake along with controlled or decreased sodium intake.
COMMENTS
Diets high in sodium (>4 g/day) and low in potassium (<2 g/day) have been associated with an
increased risk of high BP.
High dietary potassium (>3.5 g/day) is associated with a decrease in BP.
The unique focus of the present study was to analyse available randomized controlled trials (RCTs)
for the effect of potassium supplementation on BP in patients without antihypertensive medication.
The authors investigated the dose response of potassium, as well as the relationship of the sodiumto-potassium ratio (Na/K) with BP. This metanalyse was conducted according to Cochrane
Collaboration guidelines.
Finally, 15 studies fulfilling the inclusion criteria and having the necessary information contributed to
this meta-analyses.
Most of the studies used potassium chloride (KCl) tablets or elixirs for potassium supplementation
Most of the studies had a potassium intervention of 60–65 mmol/day.
Increased potassium intake leads to a decrease in SBP by 4.7 mmHg (95% CI 2. –7.0) and DBP by
3.5 mmHg (95% CI 1.3–5.7) in all patients. A greater reduction was seen in hypertensive patients
with a reduction of SBP by 6.8 mmHg (95% CI 4.3–9.3) and DBP by 4.6 mmHg (95% CI 1.8–7.5).
In conclusion, the BP-lowering effect of ingested potassium cannot be assessed alone, but must be
considered in relation to sodium in the diet. The evidence from clinical trials with a potassium and/or
sodium intervention and from the meta-analyses of these trials indicates that early dietary
modifications towards a Na/K molar ratio of about one unit could make a valuable contribution to
preventive measures for hypertension.
Pr. Jacques CHANARD
Professor of Nephrology