Abstract 1067: Dietary Phosphorus, Blood Pressure and Incidence of Hypertension in the Atherosclerosis Risk in Communities (ARIC) Study and the Multi-Ethnic Study of Atherosclerosis (MESA)
Background/objectives: Greater dietary phosphorus intake has been associated with lower levels of blood pressure (BP) in previous cross-sectional studies, but has not been studied prospectively. We used data from two prospective cohorts to explore the association of dietary phosphorus with the incidence of hypertension.
Methods: We studied 8208 participants from the Atherosclerosis Risk in Communities (ARIC) Study and 2901 from the Multi-Ethnic Study of Atherosclerosis (MESA), free of diabetes, known cardiovascular disease and hypertension at baseline. Diet was assessed using food frequency questionnaires, and BP was measured according to standardized protocols. Analyses were adjusted for age, gender, ethnicity, body mass index, waist circumference, eGFR, education, income, physical activity, smoking, study site, alcohol, and energy intake. Results from ARIC and MESA were pooled as no evidence of heterogeneity was found.
Results: At baseline, individuals in the highest vs. lowest quintile of phosphorus intake had lower systolic BP after adjustment for confounders (−2.3 mmHg, 95% confidence interval (CI) −3.2, −1.4, p for trend <0.001). A similar association was observed for diastolic BP. In follow-up visits, 3345 new cases of hypertension (blood pressure >=140/90 and/or taking antihypertensive drugs) were identified. Hypertension risk was lower in individuals with the highest vs. lowest phosphorus intake (hazard ratio: 0.89, 95% CI 0.80, 1.00, p for trend=0.02). Associations were weaker after additional adjustment for dietary calcium, potassium, and magnesium. Finally, only phosphorus from dairy products was associated with lower levels of BP and lower risk of hypertension (HR for highest vs. lowest quintile: 0.86, 95% CI: 0.76, 0.97, p for trend=0.01). However, phosphorus from other dietary sources was not associated with hypertension risk (HR for highest vs. lowest quintile: 1.04, 95% CI 0.93, 1.17, p for trend=0.48).
Conclusion: In these geographically and ethnically diverse samples in the United States, dietary phosphorus was inversely associated with lower levels of BP and a lower risk of hypertension. Overall, our findings suggest benefit from either dairy phosphorus, other nutrients in dairy products, or dairy products as a whole.