When to Initiate Treatment for Osteoporosis
Treatment for osteoporosis should be initiated in individuals with a T-score of -2.5 or less, those with a history of fragility fracture, or those with high fracture risk based on FRAX assessment. 1, 2
Diagnostic Criteria and Treatment Thresholds
Bone Mineral Density (BMD) Thresholds
- Treatment is recommended for postmenopausal women and men over 50 years with a T-score ≤ -2.5 at the lumbar spine, femoral neck, or total hip, which is consistent with the WHO definition of osteoporosis 1
- The diagnosis is based on the lowest T-score at any of the recommended DXA regions 1
- Vertebral fractures are generally diagnostic of osteoporosis, even if BMD values are not in the osteoporotic range, and warrant treatment 3
Fracture History
- Patients with a prior vertebral fracture should receive treatment regardless of BMD, as this is the strongest predictor of future fracture 1
- A history of fragility fracture (hip, spine, shoulder, forearm) is sufficient to presume a diagnosis of osteoporosis and initiate treatment, even with normal BMD 1, 2
Risk Assessment Tools
- For patients with osteopenia (T-score between -1.0 and -2.4), treatment decisions should be guided by the FRAX tool, which factors in clinical risk factors along with BMD 1
- Treatment is recommended when the 10-year probability of a hip fracture is ≥3% or a major osteoporosis-related fracture is ≥20% based on FRAX 1, 2
- BMD measurement should be performed in all patients with persistently active inflammatory disease, those repeatedly exposed to corticosteroids, and patients with long disease duration 1
Special Populations with Modified Thresholds
Glucocorticoid-Induced Osteoporosis
- In patients receiving systemic glucocorticoid therapy, treatment should be considered at a higher BMD threshold (T-score < -1.5) 3
- Patients on long-term glucocorticoids should receive calcium and vitamin D supplementation for prophylaxis 1
Cancer Survivors
- For patients on aromatase inhibitors (AI), BMD should be measured upon starting therapy 1
- If T-score is > -2.0, lifestyle measures should be implemented with BMD repeated after 1-2 years 1
- If T-score is < -2.0 or if the patient has major risk factors (prior fracture), antiresorptive treatments should be administered 1
Older Adults
- In individuals over 65 years, treatment can be initiated without a prior DEXA scan as the vast majority will have a T-score of -1.5 or below 3
- For younger individuals with likely higher BMD, DEXA is useful to determine if immediate treatment is needed or if it could be delayed until the T-score falls below -1.5 3
Treatment Selection Algorithm
- First-line treatment: Oral bisphosphonates for most patients 1, 4
- If oral bisphosphonates are contraindicated or not tolerated: Consider parenteral therapy (IV bisphosphonates or denosumab) 3, 4
- For very high-risk individuals: Consider anabolic agents (teriparatide, abaloparatide, romosozumab), particularly for those with recent vertebral fractures or hip fracture with T-score ≤ -2.5 2
Common Pitfalls to Avoid
- Relying solely on BMD without considering clinical risk factors can miss approximately half of the people who will develop osteoporotic fractures 1
- Failing to recognize that vertebral fractures warrant treatment regardless of BMD 3
- Not considering that fractures occur at higher BMD levels in glucocorticoid-induced osteoporosis compared to postmenopausal osteoporosis 3
- Discontinuing denosumab without transitioning to a bisphosphonate, which can lead to increased risk of vertebral fractures 1
- Poor adherence to medication (30-50% of patients don't take their medication correctly) 5