Vitamin D important for falls and fracture prevention in seniors and those at risk

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Sunshine is not always sufficient as source of vitamin D; supplementation is recommended for the elderly or people at risk of fracture

This statement is in response to a recent report published in the Lancet which has implied that vitamin D does not prevent osteoporosis, defined as low bone mineral density (BMD), in healthy middle-aged people (1). The authors found that vitamin D had no net effect on BMD at the spine but that it did significantly increase femoral neck BMD. Of all BMD measurements, BMD of the femoral neck is the strongest predictor of hip fracture –and this is one reason why femoral neck BMD is included in the FRAX calculator – a tool that predicts the 10-year risk of fracture. The improvement in femoral neck BMD would be expected to translate to some protection against hip fractures.

Importantly, BMD is only one of several determinants of osteoporotic fracture. Muscle strength, particularly in the lower extremities, and balance strongly influence risk of falling and falling is a powerful risk factor for fracture. The analysis in Lancet did not consider the positive role that vitamin D plays in muscle strength and balance, and thus its protective effect against falls and fractures. Vitamin D is essential for bone and muscle maintenance throughout life. In children, severe vitamin D deficiency results in inadequate mineralization of bone, leading to growth retardation and bone deformities known as rickets. As well, there is evidence that children born to mothers who are vitamin D deficient during pregnancy may have reduced bone mass, which could in turn be a risk factor for osteoporosis later in life. In older adults, vitamin D is particularly important for muscle mass, strength and balance.

But how much Vitamin D is adequate? While experts are in agreement that supplements should not be indiscriminately prescribed for the population at large, seniors in general, and especially those living in nursing homes or institutionalized, can reap benefits in terms of added protection against falls and fractures. As a result, the International Osteoporosis Foundation (IOF) recommends that people over the age of 60 years take vitamin D supplements at a dose of 800-1000 IU per day (2).

“Vitamin D supplementation is recognized to have a modest role in improving BMD in healthy people with adequate levels of vitamin D. However, it has been shown to play a role in reducing falls and fractures, especially hip fractures, in seniors and others at high risk of deficiency. Doctors should continue to prescribe it for this purpose.” said Professor Bess Dawson Hughes, Director of the Bone Metabolism Laboratory at the Jean Mayer US Dept. of Agriculture and Human Nutrition Research Center on Aging, Boston, MA.

Professor Cyrus Cooper, Chair of the IOF Committee of Scientific Advisors stated, “Health authorities should be aware of the potential role of vitamin D in helping to reduce the burden of fractures in their senior populations and people at risk of fractures. The implementation of effective low-cost strategies to ensure optimal levels of vitamin D in the at-risk population could make a substantial difference to musculoskeletal health wordwide.