Causes of osteoporotic changes in Cushing’s syndrome

Patients with Cushing’s syndrome often show osteoporotic changes.Which of the following is involved in the etiology of osteoporosis induced by Cushing’s syndrome?

• a.Decreased glucocorticoid levels that result in decreased quality of the bone
• deposited
• b.Excess deposition of osteoid
• c.Stimulation of intestinal calcium absorption
• d.Decreased PTH levels
• e.Bone fragility resulting from excess bone resorption

The answer is E.

Osteoporosis is a major problem of normal aging in both sexes but is particularly prevalent in older women. In that disease, the quality of bone is unchanged, but the balance between bone deposition and bone resorption is lost. The disease is prevalent in postmenopausal women because the protective effect of estrogens is no longer present.
Osteoporosis may also be induced by other diseases (e.g., hyperthyroidism) or drugs (e.g., alcohol and caffeine). In addition, excess glucocorticoid induces osteoporosis. For example, in Cushing’s syndrome, patients produce high levels of corticosteroids that interfere with bone metabolism. A similar pattern may be seen during prolonged steroid therapy. The result is increased bone resorption compared with bone deposition. Intestinal calcium absorption is inhibited and PTH "Parathormone" levels may be increased.