Abstract 10958: B-type Natriuretic Peptide Level is Associated with Dietary Salt Intake in Patients with Compensated Heart Failure: Evaluated by Casual Spot Urine
Introduction: Dietary salt restriction is a mainstay in the management of patients with hypertension and heart failure. However, the effect of salt intake on heart failure status is not well elucidated in daily practice. We assessed the hypothesis that B-type natriuretic peptide (BNP) level, as an Objectives marker of heart failure, is associated with sodium intake in patients with heart failure.
Subjects and Methods: Consecutive 107 patients with mild to moderate compensated heart failure (41 coronary artery disease, 17 hypertensive heart disease, 14 valvular heart disease, 7 cardiomyopathy, and 28 atrial fibrillation, 76±9 y/o, 44 female) were included. Ejection fraction was preserved (≥ 50%) in 92 (86%) patients. Angiotensin converting enzyme inhibitors/angiotensin receptor blockers, β blockers, and diuretics were used in 85, 47, and 43 % of the patients, respectively. We estimated dietary sodium intake by casual spot urine by the following equation: 24hr urinary salt excretion (g/day) = 1.285 x (Na/Cr in spot urine x expected 24hr Cr excretion)0.392. We measured BNP and blood pressure at the time of urinary sampling. We assessed the relationship of individual changes in BNP (ΔBNP) and changes in daily sodium excretion (ΔNaCl) associated with variation of sodium intake in 1 to 3 months. Results: Baseline BNP levels were 166±245 (median 90) pg/ml and estimated sodium excretions were 9.2±2.2 (median 9.2) g/day. There was a strong correlation between ?NaCl and percent changes in ΔBNP (%ΔBNP, r=0.58, p<0.001, figure). Each 1g increase in NaCl excretion was associated with a 13% increase in BNP level. Changes in systolic blood pressure (ΔSBP) were also associated with ΔNaCl (p=0.043); however, this correlation was weak (r=0.20). Multiple regression analysis showed that %?BNP was associated with ΔNaCl (p<0.001), but not with ΔSBP (p=0.29). In Conclusions, sodium intake can contribute to elevation of BNP level in patients with mild to moderate compensated heart failure.
- © 2010 by American Heart Association, Inc.