Abstract P210: Dietary Calcium and Phosphorus Intakes at Middle Age and Their Associations With Vascular Calcification at Older Age: The Atherosclerosis Risk in Communities (ARIC) Study

Background:High dietary calcium and phosphorus intakes may accelerate vascular calcification. A few studies have explored the association of dietary calcium and phosphorus intakes with vascular calcification but reported inconsistent results. Most studies relied on dietary assessment at one time point and evaluated only coronary artery calcification.Aim:To assess the associations of dietary calcium and phosphorus intakes over two time points during middle age with coronary artery and extra-coronary calcification at older age.Methods:We studied 1,940 ARIC participants who underwent chest CT scans at ≥75 years of age in 2018-19 and completed a 66-item food frequency questionnaire at two earlier visits (1987-89 and 1993-95). We calculated the average of dietary calcium and phosphorus intakes across these two visits. Calcification was quantified as Agatston score in coronary arteries, ascending aorta, descending aorta, aortic valve ring, aortic valve, and mitral valve. We ran multivariable linear (for continuous Agatston score) and logistic regression models (for Agatston score >75thpercentile).Results:The mean dietary calcium and phosphorus intake was 659 mg/day and 1,074 mg/day, respectively. Overall, we did not observe any positive associations of dietary calcium intake with vascular/valvular calcification. Rather, we saw its inverse association with ascending aorta calcification (Figure). In contrast, dietary phosphorus was not associated with the calcification of any vascular beds. The results were largely similar in linear regression models and after excluding 332 participants (17%) taking calcium supplements.Conclusion:Dietary calcium intake at middle age was largely neutral in its association with vascular calcification while showing a mild inverse association with ascending aorta calcification at older age. No evident associations were seen for dietary phosphorus. Our findings do not support a concern that a calcium or phosphorus-rich diet may accelerate vascular calcification.