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Background: Reduced potassium excretion caused by angiotensinconverting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) may increase the risk of hyperkalemia (serum potassium concentration >5 mmol/L) in the setting of increased potassium intake. Objective: The purpose of this study was to assess the effect of increasing dietary potassium on serum potassium concentration in hypertensive individuals with normal renal function treated with an ACEi or ARB. We hypothesized that an increase in dietary potassium would not provoke hyperkalemia in this population despite treatment with either an ACEi or ARB. Design: We conducted a controlled, parallel-design clinical trial in 20 hypertensive subjects with normal renal function treated with an ACEi or ARB, with random assignment to a usual diet or a high-potassium diet (HKD). Fruit and vegetable intake was used to increase potassium intake. Seram potassium concentration, 3-d food records, and 24-h urine collections were completed at baseline and 4 wk. Results: In the usual-diet group there were no statistically significant differences for potassium excretion, intake, or serum levels at end of study compared with baseline. The HKD group had significant differences in urinary potassium excretion (83 [+ or -] 26 mmol/d at baseline compared with 109 [+ or -] 35 mmol/d at 4 wk, P = 0.01) and dietary potassium intake (3775 [+ or -] 1189 mg/d at baseline compared with 5212 [+ or -] 1295 mg/d at 4 wk, P = 0.02). Despite increased potassium intake in the HKD group, serum potassium concentrations did not significantly increase from baseline at midpoint or end of study (4.1 [+ or -] 0.6, 4.3 [+ or -] 0.3, and 4.2 [+ or -] 0.4 mmol/L, respectively). Conclusion: This study demonstrates that an increase in dietary potassium over a 4-wk period is safe in hypertensive subjects who have normal renal function and are receiving ACEi and/or ARB therapy. This trial was registered at www.clinicaltrials.gov as NCT02759367. Keywords: angiotensin-converting enzyme inhibitor, [beta]-blocker, hypertension, nutrition, potassium doi: 10.3945/ajcn.115.129635

Background: Sodium-related claims on food labels should facilitate lower-sodium food choices; however, consumer attitudes and understanding of such claims are unknown. Objectives: We evaluated consumer attitudes and understanding of different types of sodium claims and the effect of having hypertension on responses to such claims. Design: Canadian consumers (n = 506), with and without hypertension, completed an online survey that contained a randomized mock-package experiment, which tested 4 packages that differed only by the claims they carried as follows: 3 sodium claims (disease risk reduction, function, and nutrient-content claims) and a tastes-great claim (control). Participants answered the same questions on attitudes and understanding of claims after seeing each package. Results: Food packages with any sodium claim resulted in more positive attitudes toward the claim and the product healthfulness than did packages with the taste control claim, although all mock packages were identical nutritionally. Having hypertension increased ratings related to product healthfulness and purchase intentions, but there was no difference in reported understanding between hypertensives and normotensives. In general, participants attributed additional health benefits to low-sodium products beyond the well-established relation of sodium and hypertension. Conclusions: Sodium claims have the potential to facilitate lower-sodium food choices. However, we caution that consumers do not seem to differentiate between different types of claims, but the nutritional profiles of foods that carry different sodium claims can potentially differ greatly in the current labeling environment. Additional educational efforts are needed to ensure that consumers do not attribute inappropriate health benefits to foods with low-sodium claims. This trial was registered at clinicaltrials.gov as NCT01764724. Am J Clin Nutr 2013;97:1288-98. doi: 10.3945/ajcn.112.052910.

Background: Twenty-four-hour urine collections are considered the optimal method for sodium intake assessment. Whether a diagnosis of heart failure (HF) or the use of loop diuretic (LD) therapy for HF compromises the validity of 24-h urine collections as a surrogate marker for sodium intake is unknown. Objective: The objective was to determine the strength of association between 24-h urine collections and food records for sodium intake assessment in non-HF cardiac patients and in HF patients stratified by LD usage. Design: Food records and 24-h urine collections were simultaneously completed for 2 consecutive days. Correlation coefficients and the Bland-Altman method of agreement described the relation between the techniques. Results: Non-HF cardiac patients (n = 96; mean [+ or -] SD age: 65 [+ or -] 11 y), HF patients who were not taking an LD (n = 47; 62 [+ or -] 11 y), and HF patients who were taking an LD (n = 62; age: 60 [+ or -] 12 y) were included. Correlation coefficients for sodium intake between food records and urine collections were r = 0.624 (P < 0.001) for non-HF cardiac patients and r = 0.678 (P < 0.001) for HF patients who were not taking an LD. However, no significant association (r = 0.132, P = 0.312) was observed for HF patients who were taking LDs. The 95% limits of agreement between the non-HF cardiac patients and the HF patients who were not taking LDs were similar but were [approximately equal to]50% wider for HF patients who were taking LDs. Conclusions: For the assessment of sodium intake, food records agree well with 24-h urine collections in non-HF patients with cardiovascular disease and in HF patients who are not receiving LD but not for HF patients who are taking LDs. Therefore, food records may provide a better estimate of sodium intake in HF patients who are receiving LD therapy. Am J Clin Nutr 2011;93:535-41. doi: 10.3945/ajcn.110.004457

Background: A low-sodium diet is an accepted treatment of patients with heart failure (HF), although minimal evidence exists on the appropriate amount of sodium intake for this population. Certain HF guidelines have liberalized dietary sodium recommendations, which actually exceed guidelines for healthy adults. Objectives: We tested the hypothesis that high sodium intake is related to acute decompensated HF (ADHF) in ambulatory HF patients. Secondary outcomes included all-cause hospitalization and mortality. Design: We prospectively enrolled medically stable, ambulatory patients with systolic HF (n = 123; mean [+ or -] SD age: 60 [+ or -] 13 y) from 2 outpatient HF clinics from 2003 to 2007. Baseline estimates of dietary sodium and other nutrient intakes were obtained from two 3-d food records. Results: The median follow-up time was 3.0 y. Mean ([+ or -]SD) sodium intakes were 1.4 [+ or -] 0.3, 2.4 [+ or -] 0.3, and 3.8 [+ or -] 0.8 g Na/d in the lower, middle, and upper tertiles, respectively. Cumulative ADHF event rates at 3 y were 12 [+ or -] 6%, 15 [+ or -] 7%, and 46 [+ or -] 11% in the low, middle, and upper tertiles, respectively (log-rank P = 0.001). For ADHF, the upper tertile was associated with an adjusted hazard ratio of 2.55 (95% CI: 1.61, 4.04; P < 0.001). Time-to-event probabilities were significant for mortality (log-rank P = 0.022) but not for all-cause hospitalization (log-rank P = 0.224). The high-sodium tertile was associated with an adjusted hazard ratio of 1.39 (95% CI: 1.06, 1.83; P = 0.018) for all-cause hospitalization and 3.54 (95% CI: 1.46, 8.62; P = 0.005) for mortality. Conclusions: To our knowledge, this study provides the first prospective evidence that ambulatory HF patients who consume higher amounts of sodium are at greater risk of an ADHF event. These data provide support for more stringent sodium intake guidelines than those currently recommended for HF patients. doi: 10.3945/ajcn.110.000174.