Treatment Thresholds for Osteoporosis
Pharmacologic treatment for osteoporosis should be initiated when the T-score is ≤ -2.5, when there is a history of fragility fracture, or when the FRAX score indicates a 10-year probability of hip fracture ≥3% or major osteoporotic fracture ≥20%. 1, 2, 3
Diagnostic Criteria and Treatment Thresholds
T-score Based Criteria:
- T-score ≤ -2.5: Diagnostic of osteoporosis and warrants treatment 1, 2
- T-score between -1.0 and -2.5 (Osteopenia): Treatment decisions should be based on additional risk factors and FRAX scores 1
- T-score < -1.5: Treatment should be considered in patients on glucocorticoid therapy, as fractures occur at higher BMD levels in glucocorticoid-induced osteoporosis 4
Fracture History:
- Presence of fragility fracture: Diagnostic of osteoporosis and indicates need for treatment, even if BMD is not in osteoporotic range 1, 3
- Vertebral fractures: Generally taken as diagnostic of osteoporosis regardless of BMD values 4
FRAX-Based Criteria:
- 10-year probability of hip fracture ≥3%: Treatment indicated 1, 3
- 10-year probability of major osteoporotic fracture ≥20%: Treatment indicated 1, 3
- FRAX calculation should be considered if T-score is between -1.0 and -2.5 to guide treatment decisions 1
Special Populations and Considerations
Patients with Chronic Liver Disease:
- T-score below -1.5: Practical guide for starting specific therapy in patients with primary biliary cholangitis and primary sclerosing cholangitis due to high risk for hip and vertebral fractures 5
Cancer Patients:
- T-score below -2.0: Therapeutic intervention strongly recommended, particularly in those with additional risk factors for fragility fracture 5
- For patients on aromatase inhibitors: BMD measurement upon starting therapy; if T-score < -2.0 or if patient has major risk factors such as prior fracture, antiresorptive treatments should be administered 5
Risk Assessment Beyond BMD
Clinical Risk Factors to Consider:
- Age >70 years
- Low body weight (BMI <20-25 kg/m²)
- Weight loss >10%
- Physical inactivity
- Corticosteroid use
- Previous fragility fracture
- Family history of hip fracture
- Smoking
- Excessive alcohol consumption 1
Secondary Causes Requiring Evaluation:
- Comprehensive evaluation mandatory with Z-score ≤ -2.0
- Endocrine disorders
- Malabsorption conditions
- Vitamin D deficiency
- Medication effects
- Chronic inflammatory conditions 1
Treatment Approach
First-line Treatment:
- Oral bisphosphonates (alendronate, risedronate) with adequate calcium (1,000-1,200 mg daily) and vitamin D (600-800 IU daily) supplementation 1, 2
Alternative Treatments:
- Denosumab or zoledronic acid for patients who cannot tolerate oral bisphosphonates or have extremely low BMD 1
- Teriparatide for patients at very high risk or with previous vertebral fractures 6
Common Pitfalls to Avoid
Relying solely on BMD: Fracture risk depends on multiple factors beyond BMD, including age, previous fractures, and other clinical risk factors 1
Ignoring treatment thresholds: Not all patients with low bone mass require pharmacologic treatment, while all patients with osteoporosis generally do 1
Overlooking age context: A T-score of -2.0 in a young individual may indicate worse long-term bone health than a T-score of -2.6 in an older individual 1
Delaying treatment in high-risk patients: Patients with fragility fractures should receive treatment regardless of BMD values 3
By following these evidence-based thresholds for osteoporosis treatment, clinicians can appropriately identify patients who would benefit from pharmacologic intervention while avoiding unnecessary treatment in lower-risk individuals.