What are the preventive measures against osteoporosis for patients on long-term corticosteroid therapy?

Preventive Measures Against Osteoporosis in Patients on Long-Term Corticosteroid Therapy

All patients starting long-term corticosteroid therapy (≥3 months) require immediate fracture risk stratification and should receive calcium (1,000-1,200 mg/day) plus vitamin D (600-800 IU/day) at minimum, with oral bisphosphonates (alendronate or risedronate preferred) added for those at moderate-to-high fracture risk. 1

Initial Risk Assessment and Stratification

Before or immediately upon starting corticosteroids, perform comprehensive fracture risk evaluation 1:

• Measure bone mineral density (BMD) with DXA scan to establish baseline T-score 1
• Calculate FRAX score to determine 10-year fracture risk (noting that standard FRAX may underestimate risk in patients on high-dose corticosteroids >7.5 mg prednisone equivalent daily) 1
• Assess for prior fragility fractures, particularly vertebral fractures which may be asymptomatic 1
• Evaluate comorbidities that increase fracture risk: diabetes, cardiovascular disease, recurrent infections, hypogonadism, smoking, excessive alcohol use, and immobility 1

Universal Preventive Measures for All Patients

Calcium and Vitamin D Supplementation (Mandatory)

Every patient on corticosteroids must receive 1:

• Calcium: 1,000-1,200 mg daily from all sources (diet plus supplements) 2
• Vitamin D: 600-800 IU daily minimum, with higher doses (800-1,000 IU/day) preferred 2
• Target serum 25(OH)D level ≥30 ng/mL 2
• Divide calcium doses into 500-600 mg increments for optimal absorption 2

The rationale is that corticosteroids inhibit intestinal calcium absorption and renal tubular calcium reabsorption, creating negative calcium balance 1, 3. All major osteoporosis trials demonstrating fracture reduction included calcium and vitamin D supplementation 2.

Lifestyle Modifications

Implement immediately 1:

• Weight-bearing exercise daily and maintain physical activity 1
• Smoking cessation 1, 3
• Limit alcohol intake 1, 3
• Maintain adequate nutrition and avoid malnutrition 1

Pharmacologic Prevention Based on Fracture Risk

Low Fracture Risk Patients

Treat with calcium and vitamin D ONLY 1

Do not add bisphosphonates or other osteoporosis medications, as this exposes patients to unnecessary harm without evidence of benefit 1.

Moderate-to-High Fracture Risk Patients

Add oral bisphosphonate (alendronate or risedronate preferred) to calcium and vitamin D 1, 4

High risk is defined as 1:

• Prior osteoporotic fracture, OR
• BMD T-score ≤-2.5, OR
• FRAX 10-year risk: major osteoporotic fracture ≥20% OR hip fracture ≥3%

Critical timing consideration: Bone loss is most rapid in the first 3-6 months of corticosteroid therapy, so preventive treatment must begin immediately—do not wait for bone loss to occur 1, 5.

Alternative Agents When Oral Bisphosphonates Are Inappropriate

If oral bisphosphonates cannot be used 1:

• Intravenous bisphosphonates (zoledronic acid annually) for malabsorption or GI intolerance 1, 4
• Teriparatide for very high-risk patients (prior fracture while on corticosteroids) 1, 6
• Denosumab as alternative option 1, 7

Pre-Treatment Safety Assessments

Before initiating bisphosphonates 1, 8:

• Dental examination and complete necessary invasive dental procedures before starting therapy to reduce osteonecrosis risk 8
• Check serum creatinine and calculate creatinine clearance (avoid IV bisphosphonates if CrCl <30 mL/min) 8
• Correct hypocalcemia before starting bisphosphonates 8
• Screen for vitamin D deficiency and correct if present 3

Special Populations Requiring Attention

Postmenopausal Women and Hypogonadal Men

Add hormone replacement therapy when appropriate, as sex hormone deficiency amplifies corticosteroid-induced bone loss 3, 9, 10

Patients on Very High-Dose Corticosteroids

Standard FRAX calculations underestimate fracture risk in patients receiving prednisone >7.5 mg/day equivalent 1. Consider more aggressive preventive therapy in these patients 1.

Patients with Hypercalciuria

Add thiazide diuretic if urinary calcium excretion exceeds 4 mg/kg/day 3

Monitoring During Corticosteroid Therapy

Establish systematic follow-up 1:

• Repeat BMD with DXA at 1 year, then every 1-3 years depending on stability 1
• Reassess fracture risk after 3-5 years to determine need for continued pharmacologic therapy 1
• Monitor for vertebral fractures with vertebral fracture assessment or spinal x-rays 1
• Check serum calcium and vitamin D levels periodically to ensure adequacy 3

Corticosteroid Dosing Considerations

Minimize skeletal toxicity by 1, 9:

• Using the lowest effective corticosteroid dose 1, 3
• Considering topical or inhaled corticosteroids when possible 3
• Keeping treatment duration under constant review and tapering when feasible 1
• Considering corticosteroid-sparing agents for the underlying disease 3

Common Pitfalls to Avoid

• Do NOT wait for bone loss to occur before starting prevention—the highest rate of bone loss occurs in the first 3-6 months 1, 5
• Do NOT treat low-risk patients with bisphosphonates—this exposes them to unnecessary harm 1
• Do NOT forget calcium and vitamin D—these are mandatory for all patients and were included in all fracture reduction trials 1, 2
• Do NOT assume FRAX is accurate for high-dose corticosteroid users—it underestimates their fracture risk 1
• Do NOT start bisphosphonates without dental evaluation—complete invasive dental work first 8