© ZEPHYR/SPL. Aortic valve replacement, 3D CT.

Effect of calcium supplementation on mortality in patients with aortic stenosis

By Rebecca Jenkins
Oral calcium supplementation with or without vitamin D is associated with lower survival and greater rates of aortic valvular replacement (AVR) in elderly patients with mild to moderate aortic stenosis, research finds.

In the retrospective longitudinal study, researchers tracked 2657 US patients with mild to moderate aortic stenosis between 2008 and 2018; the patients were aged 74 years on average and monitored for an average of more than 5.5 years.

Patients were stratified into those who did not take supplements (1292 people; 49%), those who took vitamin D alone (332 people; 12%) and those who supplemented with calcium with or without vitamin D (1033 people; 39%).

Researchers found supple­mental calcium with or without vitamin D was associated with a 31% increased risk of death from any cause and a doubling in the risk of a cardiovascular (CV) death. This group also had a 48% higher risk of AVR compared with those not taking supplements, the researchers wrote in Heart.

Patients taking supplements had significantly more diabetes, coronary artery disease, prior coronary artery bypass graft and dialysis dependence than those not taking supple­ments, the researchers said, and they were also more likely to be taking statins, warfarin and phosphate binders.

Use of calcium and vitamin D supplements had risen notably in recent years, they added, particularly among postmenopausal women susceptible to osteoporosis and bone fractures.

‘Our findings suggest that supplemental calcium in this population [elderly patients with mild to moderate aortic stenosis] does not confer any CV benefit, and instead these relationships should be thoughtfully considered in light of growing evidence and concern for CV harm particularly with unnecessary supplementation,’ the researchers concluded.

The author of an accompany­ing editorial suggested that the safety of artificial supplementary calcium intake had to be considered in an individualised and careful manner.

‘In patients with calcific [aortic stenosis] and high-risk CV [disease], the present study strongly adds to the evidence that long-term continuous calcium supplementation should be avoided if not mandatory,’ the editorialist concluded.

Professor David Brieger, Professor of Cardiology at The University of Sydney and Head of the Department of Cardiology at Sydney’s Concord Hospital, called the study findings plausible, but noted the difference in the study populations meant there was almost certainly some residual confounding contributing to the poorer outcomes among the patients receiving calcium supplementation.

‘There is already some concern about calcium supplementation among patients with coronary disease, but to my knowledge less awareness of this issue among those with aortic valve disease,’ he told Medicine Today.

He suggested clinicians should be aware of the potential association and perhaps look at alternatives to calcium for patients with these conditions who also needed treatment for osteoporosis.

‘Future studies of osteoporosis treatments should include cardiovascular outcomes in a similar way to recent diabetic trials,’ he added.
Heart 2022; doi:10.1136/ heartjnl-2021-320215.
Heart 2022; doi:10.1136/ heartjnl-2021-320672.