Exercise as it relates to Disease/Vitamin D status, muscle mass and physical activity in elderly people

This Wikibooks page is a critical appraisal of the journal article “Low Vitamin D status is associated with reduced muscle mass and impaired physical performance in frail elderly people’ by M. Tieland et al. (2013) (1)

What is the Background to this research?
Elderly populations undergo an age-associated process called sarcopenia. This is a reduction in their skeletal mass both of muscle tissue and fat (2). This study looks at the relationship between vitamin D levels in an elderly and frail population, its effect on muscle mass loss and physical performance. A decline in muscle mass and a decrease in physical performance affects the frail and elderly's ability to participate in physical activity, placing them at a higher risk of falls and injury (3). There is a strong correlation between falls, hip fracture, and mortality within 12 months following the injury (4) and much evidence that shows an increased quality of life, more social interaction and reduced mortality when elderly populations participate in physical activity (3). To understand this relationship and have elderly people stay more physically active could be largely beneficial.

Where is this research from?
Tieland, Brouwer-Brolsma, Nienabar-Rousseau, Van Loon and De Groot conducted this study from a community-dwelling in Norway, from December 2009 – September 2010. They studied pre-frail and frail people over the age of 65 and the research was published in the European Journal of clinical nutrition, a high-quality peer-reviewed journal that covers many aspects of human nutrition. The research took place in Norway, however, the correlation between vitamin D levels, vitamin D intake, and reduced appendicular lean mass are what is of interest and the findings will still be relevant in different locations.

What kind of research is this?
This research is a Cross-sectional study due to a representative subset of a population being examined at a particular point in time. It has highlighted a need for further trials as it is unclear whether the findings on low Vitamin D and low appendicular mass are a result of low vitamin D levels or due to other influencing factors.

What did the research involve?
In the Norwegian community-dwelling, 127 frail and pre-frail people over the age of 65 underwent the following tests;

Dual-energy x-ray absorptiometry was used to measure whole body and appendicular lean mass. Serum 25 Hydroxyvitamin D levels were tested from blood samples and diet was recorded in the form of a three-day record. Physical testing included one repetition maximum leg strength, grip strength, and physical activity data via accelerometer.

Limitations exist in this study as there is no control group that had vitamin D levels increased to study the effects that had on muscle mass.

What were the basic results?
53% of participants had serum 25(OH)D levels below 50nmol/1

25(OH)D status was associated with appendicular lean mass and physical activity.

Vitamin D intake was associated with the physical performance but not appendicular lean mass.

What conclusions can we take from this research?
The study suggests there is an association between low vitamin D status, reduced appendicular lean mass and decreased physical performance. It was also noted that Vitamin D intake was associated with impaired physical performance. This study highlights a need for trials that assess what impact increasing vitamin D to a healthy level of above 50 nmol/1 has on muscle mass and physical activity.

Practical Advice
There is more research required around Vitamin D status and its effects on muscle mass and physical performance, however, there is strong evidence to support physical activity in the frail and pre-frail, elderly population and it is recommended to slow the process of sarcopenia and reduce the risk of falls and injury.