Osteoporosis Therapy – Treatment & Medications

What is Osteoporosis Therapy?

Osteoporosis therapy refers to all medical and non-medical strategies aimed at slowing progressive bone loss, preserving or improving bone density, and reducing the risk of fractures. Osteoporosis is a systemic skeletal disease characterized by decreased bone mass and deterioration of bone microarchitecture, making bones fragile and prone to breaking even from minor trauma.

Causes and Risk Factors of Osteoporosis

Understanding the causes of osteoporosis helps guide the most effective treatment approach:

• Hormonal changes: The decline in estrogen after menopause accelerates bone loss in women.
• Age: Bone density naturally decreases with age in both men and women.
• Calcium and vitamin D deficiency: Both nutrients are essential for bone formation and maintenance.
• Physical inactivity: Lack of mechanical loading weakens bones over time.
• Genetic predisposition: A family history of osteoporosis increases individual risk.
• Medications: Long-term use of corticosteroids is a major secondary cause of osteoporosis.
• Smoking and excessive alcohol consumption: Both are established risk factors for bone loss.

Diagnosis of Osteoporosis

Before therapy begins, osteoporosis is diagnosed using a bone density measurement, most commonly the DXA scan (Dual-energy X-ray Absorptiometry). This test produces a T-score: a value of -2.5 or below confirms a diagnosis of osteoporosis. Additional diagnostic tools include blood tests for calcium, vitamin D, and hormone levels, as well as X-rays to identify existing fractures.

Non-Pharmacological Treatment

Lifestyle modifications form the cornerstone of osteoporosis management:

• Physical activity: Weight-bearing and resistance exercises strengthen bones and muscles and improve balance, reducing fall risk.
• Adequate calcium intake: A daily intake of 1000–1200 mg of calcium is recommended, ideally from dietary sources such as dairy products, leafy green vegetables, and mineral water.
• Vitamin D supplementation: Sufficient vitamin D levels are critical for calcium absorption. Daily intake of 800–2000 IU is typically recommended, with supplements used when dietary intake is insufficient.
• Fall prevention: Removing household hazards, using walking aids, wearing hip protectors, and engaging in physiotherapy to improve balance.
• Smoking cessation and alcohol reduction: Both positively impact bone health.
• Nutritional optimization: A balanced diet rich in protein and micronutrients supports overall bone integrity.

Pharmacological Treatment

When osteoporosis is confirmed or fracture risk is high, various classes of medications may be prescribed:

Bisphosphonates

Bisphosphonates (e.g., alendronate, risedronate, zoledronic acid) are the most widely used medications for osteoporosis. They work by inhibiting osteoclast activity (the cells responsible for bone resorption), thereby slowing bone loss and significantly reducing fracture risk. They are available as oral tablets (daily, weekly, or monthly) or as annual intravenous infusions.

Denosumab

Denosumab is a monoclonal antibody that inhibits the RANK ligand pathway, thereby reducing osteoclast activity and bone resorption. It is administered as a subcutaneous injection every six months and is particularly useful for patients with renal insufficiency, in whom bisphosphonates may be contraindicated.

Selective Estrogen Receptor Modulators (SERMs)

Raloxifene is a SERM that mimics the effects of estrogen on bone without the associated risks to breast or uterine tissue. It is primarily used in postmenopausal women with osteoporosis.

Anabolic (Bone-Building) Therapies

Unlike the antiresorptive agents listed above, anabolic medications actively stimulate new bone formation:

• Teriparatide and abaloparatide are synthetic analogues of parathyroid hormone (PTH) that stimulate osteoblast activity (bone-forming cells). They are administered via daily subcutaneous injection and are limited to a maximum treatment duration of 24 months.
• Romosozumab is an antibody targeting sclerostin that simultaneously promotes bone formation and inhibits bone resorption. It is given as a monthly injection for up to 12 months.

Hormone Replacement Therapy

In postmenopausal women, hormone replacement therapy (HRT) with estrogen can help slow bone loss. However, due to potential risks such as increased breast cancer risk, it is only recommended for osteoporosis management in carefully selected patients.

Treatment of Steroid-Induced Osteoporosis

Patients on long-term corticosteroid therapy should receive bone-protective treatment early. Standard management typically combines calcium and vitamin D supplementation with a bisphosphonate.

Treatment Goals and Monitoring

The primary goals of osteoporosis therapy are to reduce fracture risk, preserve mobility and quality of life, and prevent complications. Treatment response is monitored through regular bone density scans (every 1–2 years) and measurement of bone turnover markers in the blood.

References

1. Kanis JA et al. - European guidance for the diagnosis and management of osteoporosis in postmenopausal women. Osteoporosis International. 2019;30(1):3-44.
2. Cosman F et al. - Clinician's Guide to Prevention and Treatment of Osteoporosis. Osteoporosis International. 2014;25(10):2359-2381.
3. World Health Organization (WHO): Assessment of fracture risk and its application to screening for postmenopausal osteoporosis. WHO Technical Report Series 843. Geneva: WHO, 1994.