14 DAY TRIAL // Older people commonly take calcium supplements to fight or slow down osteoporosis. A scientific study published today on bmj.com associates these supplements with a high risk of heart attack. The authors of the study suggest that a better management of the calcium supplements in countering osteoporosis is necessary.
Doctors usually prescribe calcium supplements for improving skeletal health, but this new research implies that it could increase heart attack rates and cardiovascular problems in healthy old people. Before confirming this theory, an international team of researchers investigated the results of 11 randomized calcium supplements controlled trials, excluding vitamin D associations, on 12,000 people.
In November 2007 they have searched for randomized placebo controlled trials of calcium supplements, thanks to terms like “calcium”, “randomized controlled trial” and “placebo” as text words, in data from Medline, Embase, and the Cochrane Central Register of Controlled Trials. Scientists also looked for studies in the reference lists of meta-analysis, that were published between 1990 and 2007 and treated the effect of calcium supplements on bone density, colorectal neoplasia, fracture and blood pressure, and in two clinical trial registries - ClinicalTrials.gov and Australian New Zealand Clinical Trials Registry.
Then in March 2010, they made an update of the searchers in the electronic databases as following: Medline: January 1966-March 2010, Embase: January 1980-March 2010, Central Register of Controlled Trials: first quarter 2010. the differences in study design and quality were taken into account for bias minimization.
Scientists concluded that calcium supplements presented about a 30% increased risk of heart attack and smaller increases in the risk of stroke and mortality. These findings were valid for all trials, regardless of age, sex or supplement type. As previous research found no link between higher dietary calcium intake and increased cardiovascular risks, scientists conclude that these risks are only related to supplements, e! Science News writes.
Professor John Cleland and his colleagues suggest, in an accompanying editorial, that there are doubts about the efficiency of calcium supplements in reducing fractures. As this evidence is quite slim, patients with osteoporosis should generally not be treated with calcium supplements, with or without vitamin D association, unless they also follow an effective treatment for osteoporosis.