Exposure to which level of oral steroids increases osteoporosis risk?

• A. >7.5 mg daily for 3 months
• B. >2.5 mg daily for 6 months
• C. Any dose of steroids
• D. >10 mg daily for 1 month

Answer: (A)

The main concept being tested is that glucocorticoid-induced osteoporosis risk rises with longer use and higher doses of oral steroids. Glucocorticoids suppress bone formation by inhibiting osteoblast function and lifespan, while also increasing bone resorption. They also reduce calcium absorption from the gut and increase calcium loss by the kidneys, leading to a negative bone balance. This damage to bone accumulates over time, especially when the dose is substantial and used for several months.

The level that markedly increases osteoporosis risk is exposure to more than 7.5 mg of prednisone daily for about 3 months or longer. This threshold reflects a point at which the hormonal suppression of bone formation and the structural changes in bone become clinically meaningful, substantially raising fracture risk. Shorter courses or lower doses tend to carry less risk, and while any steroid exposure can contribute to some bone loss, the risk becomes notably higher at that higher daily dose over several months.

Shorter high-dose courses (for example, a high daily dose for only one month) or lower-dose use over many months do not carry the same level of risk as the specified threshold, which is why they are not the best answer.