Effect of increased potassium intake on cardiovascular risk factors and disease: systematic review and meta-analyses.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials and cohort studies
PubMed 23558164 · doi:10.1136/bmj.f1378
What was done
A systematic review and random-effects meta-analysis of randomized controlled trials and cohort studies searched across Cochrane Central, Medline, Embase, WHO ICTRP, and LILACS. The authors assessed the effect of increased potassium intake on blood pressure, renal function, blood lipids, catecholamine concentrations, all-cause mortality, cardiovascular disease, stroke, and coronary heart disease in adults and children.
What was found
In adults, 22 randomized controlled trials (n = 1,606) demonstrated that increased potassium intake reduced systolic blood pressure by 3.49 mm Hg (95% CI 1.82 to 5.15) and diastolic blood pressure by 1.96 mm Hg (95% CI 0.86 to 3.06). This reduction occurred in hypertensive adults but not in normotensive adults. Intakes of 90-120 mmol/day reduced systolic blood pressure by 7.16 mm Hg (95% CI 1.91 to 12.41) with no dose-response relationship. No adverse effects on renal function, blood lipids, or catecholamines were found. In 11 cohort studies (n = 127,038), higher potassium intake was associated with a reduced risk of incident stroke (RR 0.76, 95% CI 0.66 to 0.89), but not cardiovascular disease (RR 0.88, 95% CI 0.70 to 1.11) or coronary heart disease (RR 0.96, 95% CI 0.78 to 1.19). In children (3 trials, 1 cohort), systolic blood pressure change was not statistically significant (-0.28 mm Hg, 95% CI -0.49 to 1.05).
Why it matters
This review shows that increasing potassium intake effectively lowers blood pressure in hypertensive individuals and correlates with lower stroke risk, without adverse impacts on lipid levels or renal parameters in individuals with normal kidney function.
Limits
Clinical outcomes such as stroke, cardiovascular disease, and mortality were evaluated only in observational cohort studies, not randomized trials. Blood pressure reductions were not statistically significant in normotensive adults or in children, no clear dose-response gradient was found, and the findings do not generalize to patients with impaired renal potassium excretion.
Cited by
- supports Increasing dietary potassium intake has been shown to reduce the risk of stroke.