A new systematic review and meta-analysis has found no link between calcium or vitamin D supplements and a lowered risk of fractures in older adults living at home
Practice guidelines currently recommend calcium and vitamin D supplements for older people to prevent fractures in those with osteoporosis.
A study published in the Journal of the American Medical Association (JAMA) has reviewed 33 randomised trials involving more than 50,000 participants, in order to discover whether use of such supplements actually prevents fractures.
The researchers found use of supplements including calcium, vitamin D or both, compared with placebo or no treatment, was not significantly associated with a lower risk of fractures among community-dwelling adults.
The results were found to be generally consistent regardless of the dose of calcium or vitamin D, sex, fracture history, calcium intake, and baseline serum 25-hydroxyvitamin D concentration.
“These findings do not support the routine use of these supplements in community-dwelling older people,” say the authors from Tianjin Hospital in China.
Supplements may be considered in people living in residential aged care institutions, they concede, as this group is more likely to have osteoporosis because of their poorer mobility, infrequent sun exposure and poorer diet.
“Benefits of calcium and vitamin D supplementation may differ between people living in the community and people living in residential institutions,” they say.
“For these reasons it is possible that older people living in residential care communities may benefit from calcium or vitamin D supplements.”
This conclusions aligns with Australian medical guidelines.
For example, the RACGP recommends vitamin D supplements (ergocalciferol 1000 IU daily) and calcium supplements (1000-1500 mg in postmenopausal women, 800-1000mg in men) to minimise the risk of injury due to falls in older people living in residential aged care facilities.
Meta-analyses published to date have not reached consistent conclusions in regards to the association between calcium, vitamin D, or combined calcium and vitamin D supplements and fracture risk.
For example, a Cochrane review conducted in 2016 found differing results to the JAMA study.
The review of 53 trials, with a total of 91,791 participants including post-menopausal women and older men, found:
- High quality evidence that vitamin D alone is unlikely to be effective in preventing hip fracture or any new fracture.
- High quality evidence that vitamin D plus calcium results in a small reduction in hip fracture risk (equating to nine fewer hip fractures per 1000 older adults per year in high-risk populations).
- High quality evidence that vitamin D plus calcium is associated with a statistically significant reduction in incidence of new non-vertebral fractures.
- High quality evidence that vitamin D plus calcium reduced the risk of any type of fracture.
“Vitamin D alone is unlikely to prevent fractures in the doses and formulations tested so far in older people,” say the Cochrane authors.
However “supplements of vitamin D and calcium may prevent hip or any type of fracture”.
There was a small but significant increase in gastrointestinal symptoms and renal disease associated with taking the supplements.
People with kidney stones, kidney disease, high blood calcium levels, gastrointestinal disease or those at risk of heart disease should seek medical advice before taking these supplements, they say.
See the JAMA article here.
See the Cochrane review here.
See RACGP guidelines here (pages 37-39).