High sodium–potassium ratio leads to high CVD and mortality risk
MedWire News: A high sodium-potassium ratio is associated with a significantly increased risk for cardiovascular disease (CVD) and all-cause mortality in the US population, a study suggests.
"Public health recommendations should emphasize simultaneous reduction in sodium intake and increase in potassium intake," write Quanhe Yang (Centers for Disease Control and Prevention, Atlanta, Georgia, USA) and colleagues in the Archives of Internal Medicine.
Yang et al studied the estimated usual intakes of sodium and potassium of 12,267 US adults from the Third National Health and Nutrition Examination Survey.
Over a mean follow-up period of 14.8 years, 825 patients died from CVD, and 433 died from ischemic heart disease (IHD).
After adjusting for factors including gender, race, and education level, patients with higher intake of sodium (quartiles 2, 3, and 4) had a 20% increased risk for all-cause mortality (95% confidence interval [CI] 1.03-1.41 per 1000 mg/day) than those with a low sodium intake (quartile 1).
In addition, patients with a higher potassium intake had a 20% lower risk for all-cause mortality (CI 0.67-0.94 per 1000 mg/day) than those with a low potassium intake.
Finally, the risk for mortality increased linearly with increasing sodium-potassium ratio. The adjusted hazard ratios comparing the top with the bottom quartile were 1.46 for all-cause (CI 1.27-1.67) and CVD mortality (CI 1.11-1.92), and 2.15 for IHD mortality (CI 1.48-3.12).
These associations did not differ significantly by gender, race, body mass index, hypertension status, education level, or physical activity.
In a related commentary, Lynn Silver and Thomas Farley (New York City Department of Health, Queens, New York, USA) wrote: "The study by Yang et al challenges us to clarify effective public health strategies."
"It is crucial that we understand the interplay of sodium and potassium in the diet and how to optimize intake in an increasingly processed food supply without generating harm," they concluded.
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By Piriya Mahendra