Seemant Chaturvedi, MD

Observation data from the Women's Health Initiative support greater dietary potassium intake.

Increasing evidence links dietary patterns to the development of vascular disease. The Women's Health Initiative (WHI) is a study of more than 90,000 postmenopausal women. In this observational portion of the study, the researchers analyzed potassium intake and risk for stroke; they also aimed to evaluate stroke subtypes. They assessed participants' potassium intake by food frequency questionnaires administered at two times 3 years apart.

Potassium intake was divided in quartiles; mean dietary intake was 2611 mg/day. Blacks, current smokers, and nondrinkers of alcohol had relatively reduced potassium intake. The authors adjusted their analyses for these factors and for age, hypertension status, physical activity, body-mass index, hormone use, high cholesterol, aspirin use, and histories of diabetes or myocardial infarction. Compared with the lowest quartile of potassium intake, the highest quartile was associated with significantly lower overall mortality (adjusted hazard ratio, 0.90), total stroke incidence (AHR, 0.88), and ischemic stroke incidence (AHR, 0.84) but not hemorrhagic stroke incidence. The observed effect was strongest in women without a history of hypertension (AHR, 0.73). In patients with hypertension, the highest quartile of potassium intake was associated with lower overall mortality (but not stroke incidence) than the lowest quartile. Only 2.8% of participants met or exceeded the U.S. Department of Agriculture recommended daily intake of 4700 mg/day, and only 17% met the World Health Organization recommendation of 3510 mg/day.

Citation(s):

Seth A et al. Potassium intake and risk of stroke in women with hypertension and nonhypertension in the Women's Health Initiative. Stroke 2014 Sep 4; [e-pub ahead of print].