Dietary Sodium Reduction Lowers 10-Year Atherosclerotic Cardiovascular Disease Risk Score: Results from the DASH-Sodium Trial

The Dietary Approaches to Stop Hypertension (DASH) diet lowers estimated 10-year ASCVD (atherosclerotic cardiovascular disease) risk. The effects of dietary sodium reduction on ASCVD risk are uncertain. This study aims to evaluate the impact of sodium reduction, alone and combined with the DASH diet, on 10-year ASCVD risk scores. The DASH-Sodium trial randomized adults with elevated blood pressure (average systolic blood pressure of 120 to 159 mm Hg and average diastolic blood pressure of 80 to 95 mm Hg) to the DASH diet or typical American diet. Within each arm, individuals consumed 3 different levels of sodium in random order: low, medium, and high. Each period lasted 30 days. Pooled cohort equation-estimated 10-year ASCVD risk scores were calculated at baseline and at the end of each feeding period. The primary outcomes of interest were the absolute and relative differences in 10-year ASCVD risk scores from baseline. Among the 412 participants (mean age 48 ± 10 years; 57 % female, 57 % Black), sodium reduction decreased ASCVD risk scores in both dietary arms. Compared to high sodium intake, low sodium intake changed ASCVD risk by -9.4 % (95 % CI -11.7, -7.0). When compared to a typical American diet, the DASH diet changed 10-year ASCVD by -5.3 % (95 % CI -9.3, -1.2). Compared to a high sodium-control diet, the combination of both low sodium intake with DASH changed ASCVD risk by -14.1 % (95 % CI -18.6, -9.3). Sodium reduction and the DASH diet both independently reduced 10-year ASCVD risk scores. Moreover, the combined impact was additive. These findings support dietary sodium reduction in addition to the DASH diet for ASCVD prevention.