MO014A LOW-SODIUM BREAD IMPROVES THE ADHERENCE TO A LOW-SODIUM DIET IN HYPERTENSIVE SUBJECTS

Abstract

INTRODUCTION AND AIMS: Salt intake is a critical factor in hypertension and compliance to low‐sodium diets is often scarce in these patients. In this context, a significant reduction in the hidden salt of processed foods might represent an effective strategy to achieve the target sodium intake. The aim of the study was to verify the hypothesis that the use of a low‐sodium functional bread, in the context of a lowsodium diet, could increase the adherence to the latter and help to achieve blood pressure (BP) reduction. METHODS: We carried on a 6‐months multi‐center randomized controlled trial on hypertensive patients. Fifty‐four subjects suffering from stadium I‐II hypertension were enrolled and randomized in 3 study arms. Group A (n=19) followed a free diet with the use of standard Altamura bread (750 mg Na/100g), group B (n=17) followed a low‐sodium (2300 mg Na/die) diet including the use of standard Altamura bread, while group C (n=18) followed a low‐sodium (2300 mg Na/die) diet including the use of innovative, low‐sodium “PANdelCUORE” Altamura bread (280 mg Na/100g). We measured blood pressure, serum and urine sodium concentration, and endothelial function by flow‐mediated dilation (FMD). Results were expressed as mean ± SD or median and interquartile ranges. Continuous variables were analyzed by paired t‐ Student test or by Wilcoxon test, as opportune. P‐values < 0.05 were considered statistically significant. RESULTS: After 6 months, urinary sodium (113.0 [102.5‐157.5] vs 155 [150.5‐231.5] mEq/24h, p=0.02), systolic (131.67±9.08 vs 139.28±10.26 mmHg, p=0.01) and diastolic (81.94±7.89 vs 88.89±5.67 mmHg, p=0.002) BP were significantly reduced as compared to baseline levels only in group C. Urinary sodium: group A 140.5 [84.0‐ 178.0] vs 162.5 [129.3‐198.0] mEq/24h, p=0.11; group B 145.0 [124.5‐193.5] vs 148.0 [108.0‐2±9.0] mEq/24h, p=0.59. Systolic BP: group A 135.53±14.62 vs 138.42±10.42 mmHg, p=0.28; group B 132.06±12.51 vs 134.59±9.77 mmHg, p=0.51. Diastolic BP: group A 83.68±9.55 vs 85.42±6.79, p=0.37; group B 85.59±10.29 vs 84.12±5.66 mmHg, p=0.62. FMD improved in all the three groups, although more remarkably in group C (group A: 9.72±2.50 vs 7.43±1.40%, p=0.02; group B: 10.35±2.65 vs 5.81±2.03%, p=0.02; 10.84±2.68 vs 5.57±1.98%, p=0.0004). FMD did not show any significant correlation with BP. CONCLUSIONS: This is, in our knowledge, the first study exploring the differential adherence to a dietary salt restriction by comparing the use of a low‐sodium functional food vs a conventional one. We demonstrate here that the use of a low‐sodium bread increases the adherence to a low‐sodium diet and that their association is effective to significantly decrease sodium excretion and BP. Group B patients, although theoretically following a diet providing the same sodium intake of group C, failed to achieve sodium excretion and BP reduction. Moreover, we obtained a BP‐independent effect on FMD in all the enrolled patients, suggesting that even small reductions in sodium intake could result in amelioration of endothelial reactivity. Our data encourage the strategy of salt reduction in processed foods as effective for BP decrease in hypertensive patients.