Article

Lower potassium intake is associated with increased wave reflection in young healthy adults

Nutrition Journal (Impact Factor: 2.64). 04/2014; 13(1):39. DOI: 10.1186/1475-2891-13-39
Source: PubMed

ABSTRACT Increased potassium intake has been shown to lower blood pressure (BP) even in the presence of high sodium consumption however the role of dietary potassium on vascular function has received less attention. The aim of this study was to evaluate the relationship between habitual intake of sodium (Na) and potassium (K) and measures of arterial stiffness and wave reflection.
Thirty-six young healthy adults (21 M, 15 F; 24 +/- 0.6 yrs; systolic BP 117 +/- 2; diastolic BP 63 +/- 1 mmHg) recorded their dietary intake for 3 days and collected their urine for 24 hours on the 3rd day. Carotid-femoral pulse wave velocity (PWV) and the synthesis of a central aortic pressure waveform (by radial artery applanation tonometry and generalized transfer function) were performed. Aortic augmentation index (AI), an index of wave reflection, was calculated from the aortic pressure waveform.
Subjects consumed an average of 2244 kcals, 3763 mg Na, and 2876 mg of K. Average urinary K excretion was 67 +/- 5.3 mmol/24 hr, Na excretion was 157 +/- 11 mmol/24 hr and the average Na/K excretion ratio was 2.7 +/- 0.2. An inverse relationship between AI and K excretion was found (r = -0.323; p < 0.05). A positive relationship between AI and the Na/K excretion ratio was seen (r = 0.318; p < 0.05) while no relationship was noted with Na excretion alone (r = 0.071; p > 0.05). Reflection magnitude, the ratio of reflected and forward waves, was significantly associated with the Na/K excretion ratio (r = 0.365; p <0.05) but not Na or K alone. PWV did not correlate with Na or the Na/K excretion ratio (p > 0.05) but showed an inverse relationship with K excretion (r = -0.308; p < 0.05).
These data suggest that lower potassium intakes are associated with greater wave reflection and stiffer arteries in young healthy adults.

Download full-text

Full-text

Available from: David G Edwards, Aug 27, 2014
0 Followers
 · 
54 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background and Purpose-Dietary potassium has been associated with lower risk of stroke, but there are little data on dietary potassium effects on different stroke subtypes or in older women with hypertension and nonhypertension. Methods-The study population consisted of 90 137 postmenopausal women aged 50 to 79 at enrollment, free of stroke history at baseline, followed up prospectively for an average of 11 years. Outcome variables were total, ischemic, and hemorrhagic stroke, and all-cause mortality. Incidence was compared across quartiles of dietary potassium intake, and hazard ratios were obtained from Cox proportional hazards models after adjusting for potential confounding variables, and in women with hypertension and nonhypertension separately. Results-Mean dietary potassium intake was 2611 mg/d. Highest quartile of potassium intake was associated with lower incidence of ischemic and hemorrhagic stroke and total mortality. Multivariate analyses comparing highest to lowest quartile of potassium intake indicated a hazard ratio of 0.90 (95% confidence interval, 0.85-0.95) for all-cause mortality, 0.88 (95% confidence interval, 0.79-0.98) for all stroke, and 0.84 (95% confidence interval, 0.74-0.96) for ischemic stroke. The effect on ischemic stroke was more apparent in women with nonhypertension among whom there was a 27% lower risk with hazard ratio of 0.73 (95% confidence interval, 0.60-0.88), interaction P<0.10. There was no association with hemorrhagic stroke. Conclusions-High potassium intake is associated with a lower risk of all stroke and ischemic stroke, as well as all-cause mortality in older women, particularly those who are not hypertensive.
    Stroke 09/2014; 45(10). DOI:10.1161/STROKEAHA.114.006046 · 6.02 Impact Factor