Can 3 months of steroid therapy increase the risk of fracture?

Steroid Use for 3 Months Can Increase Fracture Risk

Yes, steroid therapy for 3 months can significantly increase the risk of fractures, with fracture risk rising rapidly within 3-6 months of starting therapy. 1 This risk is dose-dependent and remains even after controlling for underlying disease, age, and gender.

Mechanism of Steroid-Induced Bone Loss

Corticosteroids cause bone loss through multiple mechanisms:

• Rapid bone loss occurs during the first 6-12 months of therapy 2
• Trabecular bone (spine) is affected more than cortical bone 2
• Steroids reduce calcium absorption from the gut and increase urinary calcium losses 3
• This leads to secondary hyperparathyroidism which increases bone resorption 3
• Steroids simultaneously suppress bone formation while increasing bone resorption 4

Risk Assessment

The risk of fracture depends on several factors:

• Duration: Courses longer than 3 months are considered prolonged and significantly increase risk 3, 1
• Dose: Daily doses of prednisolone ≥5 mg lead to rapid bone loss 1
• Cumulative dose: Higher cumulative doses correlate with greater bone loss 1
• Pre-existing risk factors: Age, previous fractures, low BMI (<19 kg/m²), hypogonadism 3

The British Society of Gastroenterology specifically identifies "prolonged (>3 months) or repeated courses of steroids" as a significant risk factor for osteoporosis 3.

Monitoring and Prevention

For patients on steroid therapy for 3 months or longer:

1. Bone mineral density assessment:

   • Arrange bone mineral densitometry as soon as possible 3
   • Fracture risk increases within 3 months of starting corticosteroids 3
   • If testing cannot be done within 1 month, preventive treatment should be started in high-risk patients 3

2. Calcium and vitamin D supplementation:

   • All patients should receive 800-1000 mg/day calcium 3, 5
   • Vitamin D supplementation of 800 IU/day 3, 5
   • If vitamin D deficient, treat with 50,000 IU weekly for 6 weeks initially 3

3. Lifestyle modifications:

   • Regular weight-bearing exercise 3, 5
   • Smoking cessation 3, 5
   • Reduce excessive alcohol intake 3, 5
   • Maintain adequate nutrition (low BMI is an independent risk factor) 3

Treatment Recommendations

For patients on steroids for 3 months or more:

• First-line therapy: Oral bisphosphonates (alendronate or risedronate) 5, 6
• Second-line options: Intravenous bisphosphonates (zoledronic acid) or denosumab 5
• For malabsorption or GI side effects: Consider IV zoledronic acid 3
• For bisphosphonate intolerance: Consider denosumab or teriparatide 3

Common Pitfalls to Avoid

• Underestimating risk: Even 3 months of steroid therapy can significantly increase fracture risk 1
• Delayed intervention: Prevention should start at the onset of steroid therapy in high-risk patients 3
• Inadequate monitoring: Regular BMD testing is needed during and after treatment 5
• Focusing only on BMD: Steroids increase fracture risk independent of BMD changes 1
• Abrupt discontinuation: Steroids should be tapered to avoid withdrawal syndrome 3

Special Considerations

• Patients with pre-existing fragility fractures should be offered treatment without the need for BMD measurement 3
• The American College of Rheumatology recommends bisphosphonate therapy for most patients beginning long-term glucocorticoid therapy (≥5 mg/day for at least 3 months) 6
• The risk of fracture decreases after stopping steroid therapy but does not immediately return to baseline 1

Remember that steroid-induced osteoporosis is the most common cause of secondary osteoporosis 4, and prevention is far more effective than treating established fractures.