Abstract P403: Blood Pressure Differences Associated With OMNIHEART-like Lower Sodium Compared With Typical American Higher Sodium Nutrient Profile: INTERMAP USA

Background: The DASH-Sodium trial demonstrated beneficial effects on blood pressure (BP) of the DASH diet with lower sodium intake, compared to typical American diet with higher sodium. The subsequent OMNIHEART trial reported additional benefits for BP by replacing carbohydrate in the DASH diet with either protein or monounsaturated fats. Objective: Assess possible BP benefits of a lower sodium OMNIHEART-like diet in free-living Americans using two statistical methods: a linear OMNIHEART nutrient score, and a Bayesian approach comparing estimated BP levels with an OMNIHEART-like lower sodium nutrient profile (“OMNIHEART”) and with a typical American higher sodium profile (“Control”). Methods: Cross-sectional data include four 24-h dietary recalls, two timed 24-h urine collections, eight BP readings for 2,195 individuals ages 40-59 from the International Study on Macro/Micronutrients and Blood Pressure (INTERMAP). An OMNIHEART score (with 9 nutrient targets, based on the protein arm of the trial) was calculated for each participant and regressed on BP. For Bayesian profile regression, participants were assigned to clusters based on similarity of their nutrient profiles; pre-specified OMNIHEART and Control profiles were assigned to clusters. Posterior distributions were obtained for mean BP levels associated with OMNIHEART and Control profiles. Results: With adjustment for potential confounders, an OMNIHEART score higher by one point was associated with systolic/diastolic BP differences of 1.0/ 0.5 mmHg (both P<0.001). Mean systolic/diastolic BPs were 111.3/68.4 and 115.2/70.6 mmHg for Bayesian OMNIHEART and Control profiles respectively; controlled for possible confounders, average BP differences were 3.9/ 2.2 mmHg (P(diff≥0) =0.98/0.96). Findings were comparable for men and women, for non-hypertensive participants, and with adjustment for antihypertensive treatment. Conclusions: These findings indicate broad generalisability of DASH and OMNIHEART trial results, and support recommendations for reduced sodium OMNIHEART-style diet for prevention/control of population-wide adverse BP levels.