Many people who are living longer after a sedentary lifestyle are paying the price. The diseases osteoporosis and sarcopenia are on the rise, and their underlying biological similarities and common risk factors are creating a new syndrome: osteosarcopenia.
This syndrome exacerbates each disease’s associations with high risk of frailty, falls, fractures, hospitalisation and mortality; indeed, a study confirmed that osteosarcopenia is linked with poorer physical function than sarcopenia alone.
Early diagnosis and intervention for this “hazardous duet” are imperative, so here’s what to know.
Osteoporosis affects more than 60% of Australians over 50 years. It happens with aging when bone tissue starts deteriorating, resulting in porous bones and increased risk of fracture – even with minor falls. It can be diagnosed with a bone mineral density scan.
Sarcopenia, on the other hand, refers to accelerated loss of skeletal muscle mass and strength with aging. Affecting around one in three older adults, it can be harder to detect – especially if a person is overweight. Handgrip is typically used to measure muscle strength and gait to assess physical performance.
Bones and muscles both release hormones that impact the metabolism and functions of other tissues, and crosstalk with fat cells – together these three groups are the biggest constituent of connective tissue.
When muscle and bone tissues break down, they are typically infiltrated with fat cells which creates toxicity and inflammation and interferes with the crosstalk between them.
The only way to diagnose osteosarcopenia is with combined detection of each disease.
A history of falls and/or fractures should sound warning bells. Shortened stature is also a clue to fractures of the vertebrae due to osteoporosis. Muscle weakness and wasting can point to sarcopenia, and genetics play a role in both conditions.
People with these risk factors should be regularly screened for each disease, and experts agree that all postmenopausal women over 65 should have bone mineral density scans regardless.
Factors that lead to high risk of osteosarcopenia include older age, being female, endocrine disorders, sex steroids, low protein intake, smoking, inadequate dietary calcium intake, low vitamin D levels, and minimal mobility and function.
It is better to treat osteosarcopenia as one condition, using an integrated approach, rather than the two contributing diseases separately.
Inactivity is a primary, modifiable cause of muscle wasting and bone density loss, as the health of both bones and muscles relies on mechanical stimulus. Resistance training – increasing muscle strength – is most important.
Regular weight-bearing and muscle-strengthening exercises that target agility, strength, posture and balance have demonstrated benefits and are recommended at least three times a week for 20 minutes or more.
Protein is vital for bone and muscle and is recommended at more than 0.8 mg/kg body weight per day. Calcium and vitamin D also have dual benefits for bone and muscle; together with protein they can help reduce falls, fractures and disability.
Regular activity and a healthy diet with adequate nutrition are also the most effective ways to prevent age-related deterioration of bone and muscle and retain independence and optimal quality of life.
It affects about one in three older adults, it’s debilitating, it fast-tracks mortality, and finally it is gaining greater recognition.
Sarcopenia Australia Day was officially launched just last year in July 2018 by the Australian Institute for Musculoskeletal Science, the University of Melbourne and Western Health to increase awareness, detection and treatment of this muscle wasting disease.
In November 2016, Sarcopenia was dubbed the “‘new’ disease on the block” by SBS news, shortly after it was recognised by the World Health Organisation and given its own ICD-10 (International Classification of Diseases) code in October that year.
Its label as a disease may be new, but the condition certainly isn’t.
Irving Rosenberg first devised the term sarcopenia (sarx = flesh; penia = loss) in 1988 to describe the disease, saying, “no single feature of age-related decline (is) more striking than the decline in lean body mass.”
Despite this, the disease didn’t gain traction until more recent years. Professor Gustavo Duque from the University of Melbourne is pushing for greater recognition of the condition.
He told SBS news that “People progressively lose the capacity to do the things that they usually do and they don’t know why.”
The disease is “to muscles what osteoporosis is to bones”, but doctors are often unaware of the condition, he said.
It can be particularly tricky to detect if patients are not visually wasting away; low muscle mass can even coexist with obesity.
Some muscle wasting is normal with ageing, but thousands of older Australians have accelerated muscle loss, leading to increased risk of falls, fractures, and hospitalisation.
And it affects more than just muscles. Muscle mass makes up more than half of overall body tissue, and so far research suggests its degradation has widespread ramifications including poor wound healing, increased risk of insulin resistance, type 2 diabetes, poor lung function and even breast cancer.
Diet and exercise become increasingly important as we age, and our body’s ability to repair and regenerate muscle is not what it used to be.
Physical activity helps to maintain muscle mass and strength – especially resistance training. But any activity can help, even small, regular movements or 15 minutes of cardiovascular exercise can promote muscle growth.
The importance of protein cannot be underestimated. Protein has numerous functions for maintaining the body’s metabolic processes and is important for maintaining lean muscle mass and healthy bone density.
Other nutrients can also help, including Vitamin D, creatinine supplementation (combined with resistance training), and minerals such as magnesium, selenium and zinc.
Importantly, the best results come from combining movement with good nutrition for stronger muscles and better, longer quality of life.
A new study has found that adults over 84 years who eat more protein are less likely to suffer disability, which is a significant problem in this growing age group.
Researchers took food diaries from 722 community-dwelling adults in the UK and measured disability according to difficulty performing daily activities like moving around the house, getting in and out of a chair, shopping, walking and climbing stairs.
Progression of disability, followed up 18 months, 3 and 5 years later, fell into four distinct categories, from very low to severe.
Results showed that adults who ate more protein were less likely to become disabled over the 5-year follow-up than those with lower protein intake, after factoring in gender, education, physical activity, cognition and chronic diseases.
Lead author of the study, Dr Nuno Mendonca, told Nutrition Insight, “We believe that the largest benefit of protein consumption is due to delaying muscle mass and strength loss.”
Protein is critical for maintaining lean muscle mass, needed for strength and mobility, and healthy bone density. Not only that, if protein stores are low, the liver will draw on the muscle’s protein stores to maintain energy levels between meals.
Dietary protein also has a multitude of other important bodily functions including formation of enzymes and hormones, transporting molecules through the bloodstream, manufacturing antibodies and regulating acid-alkaline levels.
Adults in the study who consumed 1g protein per kg of body weight each day were more likely to have lower disability, supporting calls to increase recommended protein intakes.
For a 58 kg person, that could easily be met by eating 2 eggs for breakfast, 100g yoghurt with lunch and a 100g serve of salmon for dinner – all soft foods for people with dentition or swallowing difficulties.
For adults with poor appetite, eating small meals with protein shakes for morning and afternoon tea will help boost protein intake.
It’s important to note that protein needs increase when the body is stressed by infection, burns, cancer or injury.
And to maximise muscle mass and strength, the benefits of regular physical activity in conjunction with protein intake cannot be underestimated.
Twenty years ago, the term “sarcopenia” – Greek for “poverty of flesh” – was coined to describe the muscle wasting that occurs with aging.
Often unnoticed, this condition can dramatically impact quality of life and independent living. Experts propose that muscle mass, strength and function should be assessed to diagnose sarcopenia.
Awareness of sarcopenia – affecting at least a third of older Australians – is slowly gaining momentum. So too are its wide-ranging effects on health, including its potential to cause type 2 diabetes.
New research suggests it could impact lung function and breast cancer risk.
Poor lung function can lead to respiratory complications like pneumonia and bronchitis as well as broader problems like heart disease and death.
Lungs rely on healthy muscles in the respiratory system, particularly the diaphragm, to help breathe in oxygen and expel carbon dioxide.
Handgrip strength is an easy, quick measure of muscle strength. The test involves simply squeezing a small object as hard as possible to measure the strength of your grip.
Handgrip strength is a useful indicator of general health, and has been related to nutrition status and walking ability. Also a useful indicator of low muscle mass, hand-grip strength can be used to diagnose sarcopenia.
Weak lung function has been linked to poor handgrip strength in hospitals or nursing homes. Korean researchers wanted to test if handgrip strength could predict lung function, measured using standard pulmonary (lung) function tests, in a national population study of healthy community-dwelling women aged 65-79.
They found that as handgrip strength declined, so did lung capacity – after adjusting for several other factors like age, education and physical activity levels.
The researchers suggest handgrip strength could be a useful public health tool for identifying potential impairment in lung function.
Sarcopenia and excess fat have been previously related to higher risk of mortality from metastatic (secondary) breast cancer.
Researchers from the United States and Canada recently investigated whether this was the case with nonmetastatic (primary) breast cancer. They measured muscle mass, muscle quality and fat in 3,241 women with stage 2 or 3 breast cancer, i.e. cancer that has not spread to other organs, and followed them up for at least 6 years.
A third of patients had sarcopenia, and they were 41 percent more likely to die early than those without sarcopenia. Women with highest amounts of fat were 35 percent more likely to die early than those with low fat levels.
Women who had lower muscle mass and higher levels of fat were 89 percent less likely to survive. Interestingly, body mass index (BMI; height/weight ratio) was not associated with survival.
It is possible, the researchers say, that women with more aggressive cancer may have lost more muscle mass early in their cancer as a result. Women with higher muscle mass may also have had healthier lifestyle habits more generally.
They suggest, however, that clinical measures of muscle mass and fat might help provide prognostic information to help guide treatment.
These studies build on evidence that says muscle matters – more than we might realise. Better health outcomes with aging can be achieved with simple lifestyle habits that embrace physical activity and good nutrition to prevent loss of muscle mass.