Potassium supplements yield modest BP reductions in hypertension

Oral potassium supplementation appears to confer modest reductions in clinic blood pressure (BP) levels in patients with untreated primary hypertension, according to a meta-analysis.

Researchers searched multiple online databases for randomized parallel or crossover trials comparing oral potassium supplementation with placebo, sodium chloride, or no treatment in adults with untreated primary hypertension.

A total of 19 trials, which involved 803 participants, were included in the meta-analysis. Across the trials, potassium was most often given as potassium chloride, with doses ranging from 30–140 mmol/day (median 64 mmol/day). The median duration of supplementation was 4 weeks (range, 2–16).

Pooled data showed that compared with control, potassium reduced clinic systolic BP by 5.3 mm Hg and diastolic BP by 4.5 mm Hg. Potassium was also associated with reductions in 24‐h ambulatory BP, although the magnitude was smaller: 2.8 mm Hg for systolic BP and 3.2 mm Hg for diastolic BP.

In terms of safety, adverse events occurred more frequently with potassium vs control (12.8 percent vs 3.2 percent). Withdrawals and adverse event leading to withdrawals were uncommon.

Heterogeneity across trials was substantial, and evidence on ambulatory BP was limited.

“The evidence supports, at most, a conditional adjunctive role for oral potassium supplementation in selected adults with untreated primary hypertension, preserved renal function, and access to biochemical monitoring,” the researchers said.

They also cautioned against interpreting the findings as supporting potassium supplementation as an alternative to guideline‐directed BP-lowering therapy when pharmacologic treatment is indicated.