By Lilian Anekwe
Researchers have called for the use of calcium supplements in osteoporosis 'to be reassessed' after a meta-analysis published in the BMJ today found they increased the risk of myocardial infarctions and cardiovascular events.
A study by a team of researchers from the UK and New Zealand, published today in the BMJ, found calcium supplements were associated with a 31% increased risk of heart attack and a non-significant 20% increase in the risk of stroke and mortality.
Calcium supplements, in combination with vitamin D, are recommended by NICE as part of the management of osteoporosis and, are commonly prescribed to patients with other musculoskeletal diseases as well as women on long-term steroids and hormone replacement therapy.
Pulse first reported on the link between calcium supplements and increased risk of cardiovascular events when the research was presented at the World Congress on Osteoporosis in May.
The meta-analysis of 8,000 patients in five randomised controlled trials were given calcium supplements – without vitamin D – found that when given at doses of more than 500mg a day, there was a 31% increase in the risk of myocardial infarction compared with patients given a placebo.
Calcium supplements also increased the risk of stroke by 20%, death by 9%, and the risk of a heart attack, stroke or sudden death by 18% compared to placebo, although these increases in risk did not reach statistical significance.
As Pulse reported, the researchers called for a reassessment of the role of calcium supplements in the management of osteoporosis.
Professor Ian Reid, professor of medicine and endocrinology at the University of Auckland, concluded: ‘Although the magnitude of the increase in risk is modest, the widespread use of calcium supplements means that even a small increase in incidence of cardiovascular disease could translate into a large burden of disease in the population.
‘The likely adverse effect of calcium supplements on cardiovascular events, taken together with the possible adverse effect on incidence of hip fracture and its modest overall efficacy in reducing fracture, suggest that a reassessment of the role of calcium supplements in the prevention and treatment of osteoporosis is warranted.'
In an accompanying editorial, Professor John Cleland, professor of cardiology at the University of Hull, said calcium ‘should not be given without concomitant treatment'.
‘Calcium supplements, given alone, improve bone mineral density, but they are ineffective in reducing the risk of fractures and might even increase risk, they might increase the risk of cardiovascular events, and they do not reduce mortality.
'They seem to be unnecessary in adults with an adequate diet. Given the uncertain benefits of calcium supplements, any level of risk is unwarranted.'
Calcium supplements are part of the management of osteoporosis
