Osteosarcopenia – Causes, Diagnosis and Treatment

What is Osteosarcopenia?

Osteosarcopenia is a clinical condition in which a person is simultaneously affected by osteoporosis (reduced bone density and bone quality) and sarcopenia (loss of muscle mass and strength). The two conditions reinforce each other and together substantially increase the risk of falls, fractures and functional decline in daily life.

Osteosarcopenia is not uncommon: studies indicate that a significant proportion of adults over the age of 65 are affected by both conditions concurrently. Because bone and muscle tissue are closely interconnected through mechanical, hormonal and metabolic signalling pathways, the deterioration of one tissue often accelerates the deterioration of the other.

Causes and Risk Factors

Osteosarcopenia develops through an interplay of several factors that affect both bone and muscle health:

• Advancing age: From around the age of 40, bone density and muscle mass begin to decline physiologically.
• Hormonal changes: The decline in oestrogen after menopause and reduced testosterone levels negatively affect both bone and muscle metabolism.
• Physical inactivity: A sedentary lifestyle significantly accelerates the loss of both bone and muscle tissue.
• Nutritional deficiencies: Inadequate intake of protein, calcium, vitamin D and other micronutrients is one of the most important modifiable risk factors.
• Chronic diseases: Diabetes mellitus, chronic inflammation, kidney insufficiency and other conditions increase the risk.
• Medications: Long-term use of corticosteroids and certain other drugs can damage both bone and muscle.
• Smoking and alcohol: Both negatively influence bone and muscle metabolism.

Symptoms and Clinical Consequences

Osteosarcopenia often develops gradually and may go unnoticed for a long time. Common signs can include:

• Loss of height and postural changes
• Muscle wasting, particularly in the legs and arms
• Reduced grip strength and walking speed
• Increased tendency to fall
• Back or joint pain
• Bone fractures from minor trauma, known as fragility fractures

The simultaneous weakening of bones and muscles means that falls not only occur more frequently but also result in more severe consequences compared with individuals affected by only one of the two conditions.

Diagnosis

Diagnosing osteosarcopenia requires a combined assessment of bone and muscle health:

• DXA scan (Dual-Energy X-ray Absorptiometry): The standard method for measuring bone mineral density and body composition, including muscle and fat mass.
• Muscle function tests: Handgrip dynamometry, gait speed assessment and the five-times chair stand test.
• Laboratory parameters: Calcium, vitamin D (25-OH vitamin D), parathyroid hormone and inflammatory markers.
• Clinical history and fall history.

International consensus groups such as the EWGSOP2 (European Working Group on Sarcopenia in Older People) and the IOF (International Osteoporosis Foundation) have published diagnostic criteria for both conditions individually.

Treatment and Prevention

Physical Activity

Regular resistance and strength training is one of the most effective interventions for improving muscle mass and bone density. Balance exercises and aerobic training additionally support fall prevention and overall musculoskeletal function.

Nutrition and Nutrient Supply

An adequate intake of protein (at least 1.0-1.2 g per kg body weight per day in older adults, according to ESPEN guidelines), calcium (approximately 1000-1200 mg per day) and vitamin D (at least 800-1000 IU per day) is essential for maintaining bone and muscle health. Magnesium, vitamin K2, zinc and collagen peptides also play supportive roles in bone and muscle metabolism.

For individuals who are unable to meet their increased nutrient requirements through diet alone, targeted supplementation may be beneficial. Our bone complex supplement for comprehensive bone and muscle support was specifically developed to address these nutritional needs.

Medical Treatment

For clinically confirmed osteoporosis, the following medications may be used depending on severity:

• Bisphosphonates (e.g. alendronic acid): Inhibit bone resorption.
• Denosumab: A monoclonal antibody that reduces bone breakdown.
• Teriparatide: Stimulates bone formation in severe osteoporosis.
• Hormone replacement therapy (in postmenopausal women, based on individual medical assessment).

Currently, no approved medications exist specifically for sarcopenia. Treatment relies primarily on exercise and nutritional optimisation.

Fall Prevention

Fall prevention programmes, home environment modifications (such as removing trip hazards and improving lighting) and reviewing medications that increase fall risk are important components of management. Ensuring adequate intake of key nutrients that support bone density and muscle function is a valuable complement to these measures. You can find more details about our nutritional supplement for bone and muscle health on the dedicated product page.

Osteosarcopenia and Quality of Life

Osteosarcopenia is not only a medical challenge but also has a significant impact on the independence and quality of life of older adults. Those affected commonly report difficulties with everyday activities, social withdrawal, fear of falling and an increased need for care. Early prevention and interdisciplinary treatment can substantially improve quality of life and delay the need for long-term care.

A comprehensive approach combining regular exercise, a balanced diet rich in relevant nutrients and, where necessary, targeted supplementation is particularly effective. Learn more about how our Knochen-Komplex product supports the musculoskeletal system as part of a preventive strategy.

Frequently Asked Questions

What is the difference between osteosarcopenia and osteoporosis or sarcopenia alone?

Osteoporosis refers exclusively to reduced bone density and bone quality, while sarcopenia describes the loss of muscle mass and strength. Osteosarcopenia is diagnosed when both conditions are present simultaneously. This combination is particularly hazardous because weak muscles increase the risk of falls while weakened bones greatly raise the likelihood of a fracture if a fall occurs.

How common is osteosarcopenia?

Studies estimate that between 5 and 37 percent of adults over 65 are simultaneously affected by both osteoporosis and sarcopenia, depending on the study population and diagnostic criteria used. The prevalence is likely even higher among people over 80 and in nursing home residents.

Can osteosarcopenia be reversed?

A complete reversal is rarely achievable, but resistance training combined with optimised protein and micronutrient intake can produce measurable improvements in both muscle mass and bone density. Early intervention can significantly slow progression and help preserve musculoskeletal function and independence.

Which nutrients are most important in osteosarcopenia?

Calcium, vitamin D and protein are the most critical nutrients. Calcium and vitamin D are essential for bone mineralisation and density, while adequate protein intake supports muscle maintenance and growth. Magnesium, vitamin K2 and zinc also play important supporting roles in calcium metabolism and bone health.

At what age should one start thinking about osteosarcopenia?

Prevention ideally begins in middle age, from around 40 to 50 years, as bone density and muscle mass start declining gradually at this point. Prevention becomes especially important after menopause in women and from age 65 onwards in both sexes. Regular medical check-ups are strongly recommended.

How is osteosarcopenia diagnosed?

Diagnosis involves a combination of DXA bone density measurement, muscle function tests (grip strength, gait speed), body composition analysis and laboratory values including vitamin D, calcium and inflammatory markers. No single unified international diagnostic standard for osteosarcopenia exists yet; clinicians typically apply the established criteria for each individual condition in combination.

References

1. Kirk B, Zanker J, Duque G. Osteosarcopenia: epidemiology, diagnosis, and treatment - facts and numbers. Journal of Cachexia, Sarcopenia and Muscle. 2020;11(3):609-618.
2. Binkley N, Krueger D, Buehring B. What's in a name revisited: should osteoporosis and sarcopenia be considered components of dysmobility syndrome? Osteoporosis International. 2013;24(12):2955-2959.
3. Cruz-Jentoft AJ, et al. Sarcopenia: revised European consensus on definition and diagnosis. Age and Ageing. 2019;48(1):16-31.