Medical Matters: Sarcopenia – what is it and how can we prevent it?
If we are physically inactive, we can lose up to 5 per cent of our muscle mass per decade after age 30
One of the best ways to treat, and indeed prevent, sarcopenia is exercise. Photograph: Getty Images/iStockphoto
Growing old brings its health challenges, many in the form of diseases associated with ageing. Osteoporosis and osteoarthritis readily come to mind. But now we have a relatively new kid on the block – sarcopenia.
First used to define a distinct clinical condition about two decades ago, and with some remaining uncertainty about its clinical relevance, the term sarcopenia comes from the Greek “sarx”, meaning flesh, and “penia” for loss; it describes the progressive decline in muscle mass that accompanies ageing.
Sarcopenia was a focus of the recent World Congress on Osteoporosis, Osteoarthritis and Musculoskeletal Diseases. Researchers from the University of Liège, Belgium, presented a study that helps to put numbers on the growing burden of sarcopenia in Europe. In doing so they had to allow for the absence of a global consensus on the definition of the disease for diagnostic purposes.
In general terms, signs of the disorder include loss of muscle mass and strength, which in turn affects balance, gait and overall ability to perform tasks of daily living. To allow for diagnostic uncertainty, the Belgian study looked at two different scenarios based on different diagnostic criteria.
Using the Eurostat online database, researchers calculated age-specific population projections from 2016-2045 for 28 European countries. According to their lowest prevalence estimate, the number of Europeans with sarcopenia in 2016 is over 10.8 million. By 2045 they reckon this will rise to 18.7 million people, a 72 per cent increase. In the worst case scenario, Dr Olivier Ethgen and his colleagues estimated the number of people with sarcopenia would rise from 19.7 million at present to 32.3 million in 2045.
Now when I see big numbers associated with a “new” disease entity, my jaundiced eye becomes suspicious. In the past warnings like this have been driven by disease mongering on the part of those with a commercial interest in finding a disease to match a pre-existing treatment.
No commercial agendaBut in fairness to the various experts who spoke at the congress I cannot detect a commercial agenda behind the sudden blossoming of sarcopenia. Rather it seems to be driven by a genuine prevention motive.
At some point in our 30s we begin to lose muscle mass and function. If we are physically inactive, we can lose up to 5 per cent of our muscle mass per decade after the age of 30. Although sarcopenia is mostly seen in people who are inactive, the fact that it also occurs in people who stay physically active throughout life suggests there are other factors involved in its development.
These include: an age-related reduction in nerve cells responsible for sending signals from the brain to the muscles to initiate movement; a reduction in the concentration of hormones such as growth hormone and testosterone; a decrease in the body’s ability to synthesise protein; and an inadequate intake of protein to sustain muscle mass.
One of the best ways to treat (and indeed prevent) sarcopenia is exercise. Resistance training or strength training – using exercises that increase muscle strength and endurance with weights or resistance bands – has been shown to have a positive effect on our neuromuscular system, hormone concentrations and protein synthesis.
Good nutrition also plays a role. Aim to have a varied diet, rich in fruit and vegetables and good quality protein.
According to the National Dairy Council, not all proteins are the same: “Proteins are made up of building blocks called amino acids, with an amino acid called leucine being one of the most effective at stimulating muscle growth. Protein sources that are rich in leucine include lean meat, eggs and dairy. Dairy products such as milk, yogurt and cheese are not only good sources of protein but also contain a matrix of other vital nutrients including calcium, riboflavin, vitamin B12, iodine, potassium and phosphorus,” it says.
Finally, although drugs such as testosterone and HRT may have benefits, drug therapy is not recommended for sarcopenia.