Calcium and vitamin D supplements were not associated with increased risk of cardiovascular events, supporting the cardiovascular safety of such supplementation, according to the UK Biobank data presented at the recent 2016 World Congress on Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (WCO-IOF-ESCEO 2016) held in Malaga, Spain.

“Calcium supplementation is widely used, including as an adjunct to therapy for osteoporosis,” said lead author Professor Nicholas Harvey, a consultant rheumatologist from the MRC Lifecourse Epidemiology Unit at the University of Southampton in Southampton, UK.

Prior studies have reported conflicting information about whether or not supplemental calcium and/or vitamin D increased the risk of cardiovascular disease (CVD), myocardial infarction (MI), CVD death or other heart-related incidents, and most of these were not designed to specifically examine the relationships.

“Our results, using the largest single study to date, provide reassurance that such supplementation appears safe,” said Harvey.

The longitudinal study analysed data from 502,664 participants (mean age 58 years) in the UK Biobank. Out of these, 34,890 (6.94 percent) reported taking calcium supplements, 20,004 (3.97 percent) took vitamin D supplements, and 10,406 (2.1 percent) took both supplements. [WCO-IOF-ESCEO 2016; abstract P311]

The researchers found no association between taking calcium supplements and risk of incident hospital admission (ICD-10) with ischaemic heart disease (IHD) (for women: adjusted hazard ratio [adjHR], 1.06, 95 percent confidence interval [CI], 0.85-1.31; p=0.62, and for men: adjHR, 1.02, 95 percent CI, 0.80-1.30; p=0.87).

Also, taking calcium supplements was not associated with risk of death from IHD (for women: adjHR, 0.71, 95 percent CI, 0.32-1.61; p=0.42, and for men: adjHR, 0.92, 95 percent CI, 0.52-1.62; p=0.76). Similar results were observed for vitamin D or combination supplements.

These findings remained even after accounting for confounders such as age, body mass index (BMI), educational status, blood pressure, and in women, use of hormone replacement therapy (HRT).

The UK Biobank is a large prospective cohort of 502,664 people aged 40 to 69 years. Calcium and vitamin D supplementation was self-reported by the participants, who were followed-up on ICD-10 for IHD and IHD-related death for up to 7 years.