Long-term use of calcium supplements is not associated with increased risk for development or progression of abdominal aortic calcification (AAC) in older women, according to study results presented at the American Society for Bone and Mineral Research 2019 Annual Meeting, held September 20 to 23 in Orlando, Florida.
Calcium supplements with or without vitamin D are frequently used in patients for whom dietary calcium intake is below the recommended levels. Previous studies have suggested a possible link between the use of these supplements and an increased risk for arterial calcification and myocardial infarction. In the current study, the goal was to explore the association between calcium supplements and risk for progression of AAC compared with placebo.
Data from the Calcium Intake Fracture Outcome Study, a double-blind placebo-controlled trial of 1.2 g elemental calcium in the form of calcium carbonate, were used for this study.
The study cohort included 904 women >70 years of age (mean age, 74.9±2.6 years) with available lateral spine images scored using the AAC24 semiquantitative method. Assessment of AAC24 was completed by an experienced investigator at baseline (1998-1999) and at the end of the trial (2003-2004).
In the intention-to-treat analysis or the per protocol analysis, which included 626 women who were taking ≥80% of their tablets, there was no difference in the change in AAC24 scores between the groups. This finding did not change after adjustment for age, dietary calcium, and other cardiovascular risk factors.
In a similar fashion, there was no difference between groups among 301 women with evidence of an AAC24 score progression ≥2, either in the intention-to-treat analysis (34.3% in the calcium group vs 32.3% in the placebo group; P =.572) or in the per protocol analysis (37.0% vs 30.5%, respectively; P =.091). Furthermore, there was no difference between the groups in women with severe AAC (AAC24 score >5) at baseline.
Although there was also no significant difference between the calcium supplementation and placebo groups in women with no AAC at baseline (AAC24 score, 0; 180 women) who developed any grade of AAC (AAC24 progression, ≥1; 50 women), for women who took ≥80% of their tablets, development of AAC was less frequent in those assigned to take calcium supplements compared with the placebo group (23.0% vs 42.4%, respectively; P =.032).
“[T]his study using data from a large randomized controlled trial did not identify evidence that long-term calcium supplementation increases the development or progression of abdominal aortic calcification,” concluded the researchers.
Lewis J, Lim W, Schousboe J, et al. Long-term effects of calcium supplementation on abdominal aortic calcification in older women: analysis of a 5-year double-blind randomized controlled trial. Presented at: American Society for Bone and Mineral Research 2019 Annual Meeting; September 20-23, 2019; Orlando, FL. Abstract LB-1168.