Osteosarcopenia is the existence of osteoporosis and sarcopenia–two chronic musculoskeletal conditions–at the same time. These conditions are commonly associated with ageing.
Unfortunately the presence of both conditions leads to worse outcomes than what is seen when either condition exists on its own. Consequently, people with osteosarcopenia have a higher risk for disability, admission in aged care and depression.
Symptoms & causes
Osteosarcopenia often does not present with any symptoms until the person experiences a major catastrophic fracture.
Symptoms of osteosarcopenia may include:
- past history of falls and/or fractures in older people
- excessive outward curvature of the spine, causing hunching of the back
- loss of height (due to vertebral fractures after middle age)
- muscle weakness, problems with balance, falls, and decreasing overall function.
Primary osteosarcopenia arises from age-related changes in bone and declines in muscle function. From age 60 onwards, people experience a natural progressive decline in bone mineral density (~1–1.5% per year), muscle mass (~1% per year) and strength (~2.5–3% per year). These changes predispose older people to the risk of osteoporosis and sarcopenia.
Secondary osteosarcopenia may arise from underlying medical conditions, which if treated can lead to improvements in a person’s overall condition. Secondary causes include:
- endocrine (hormonal) conditions, e.g. Type II diabetes mellitus, hypogonadism, early menopause, thyroid disorders, hypercalciuria, Paget’s disease, cortisol excess and hypogonadism
- inflammatory disease e.g. rheumatoid arthritis
- malignant disease e.g. cancer (solid organ & blood-based)
- organ failure e.g. heart failure, kidney failure.
A number of risk factors have been identified for osteosarcopenia. These include:
- older age
- female sex
- use of oral glucocorticoid medications
- female menopause
- current smoker
- high alcohol intake
- low dietary protein and/or calcium intake
- low serum vitamin D levels
- medical conditions – hypogonadism (men), hyperparathyroidism, rheumatoid arthritis, chronic kidney disease
- low mobility and function
- living in residential aged care facilities.
Osteosarcopenia has only recently been defined as a medical condition. Consequently, few studies have specifically looked at its prevention. However, it is expected that the preventive measures recommended for osteoporosis and sarcopenia could have a beneficial effect in patients at risk for osteopsarcopenia.
Adopting a healthy lifestyle that incorporates adequate amounts of exercise is recommended for general wellbeing. There is evidence that–for those with deficiencies–combining resistance and balance exercises with the use of nutritional supplements (whey protein, vitamin D, calcium, creatine), as directed by a clinician, may reduce progression to osteosarcopenia.
An osteosarcopenia diagnosis requires clear demonstration of the coexistence of both osteoporosis and sarcopenia. A person’s history of previous fractures and falls will often alert their clinician to the possibility of osteosarcopenia.
For the diagnosis, a comprehensive geriatric assessment is undertaken including review of the person’s medical history and risk factors. Several investigations are used to confirm diagnosis. Imaging tools such as DXA (i.e. dual‐energy X‐ray absorptiometry, also used for the diagnosis of osteoporosis) are used to quantify muscle and bone mass. Muscle strength (grip strength) and functional capacity (gait or walking speed) are also assessed using a number of approaches.
Additional investigations may be undertaken to identify secondary causes of osteosarcopenia. These may include measuring calcium and vitamin D levels, measuring parathyroid hormone levels, assessing kidney function (creatinine/estimated glomerular filtration rate) and measuring albumin levels. In men serum testosterone levels may also be investigated.
These comprehensive assessments for osteosarcopenia are performed at our Falls and Fractures Clinic at AIMSS.
Treatment of osteosarcopenia includes a combination of lifestyle changes and the use of medications as outlined below.
Lifestyle recommendations include smoking cessation and guidance on reducing/restricting alcohol consumption.
Physical activity recommendations include undertaking at least two or three sessions per week of resistance and balance training, for a minimum of 30 minutes per session. People with mobility issues that present a barrier to exercise might require referral to a physiotherapist or another relevant health professional.
To optimise musculoskeletal health nutritional supplements may be recommended. This includes the use of protein supplements, vitamin D and calcium.
Osteoporosis medications are used to treat the osteoporosis associated with osteosarcopenia. Therapies include antiresorptive (denosumab, bisphosphonates), anabolic (teriparatide, abaloparatide), antisclerostin (romosozumab), and hormonal (hormone replacement therapy, selective oestrogen receptor modulators) agents.
Currently, there are no medications available for treating sarcopenia. A number of new treatments are being investigated for sarcopenia and these may be available in a few years time.