[Secondary osteoporosis. Clinical approach to secondary osteoporosis.]

Osteoporosis is deterioration of bone integrity caused by bone loss(bone mineral density decrease)due to failure of coupling of bone resorption and bone formation. Various pathophysiological conditions other than natural menopause or aging are involved in the development of osteoporosis. When there is a specific cause of the disease, it is referred to as secondary osteoporosis. Secondary osteoporosis is usually thought to lead to an increased risk of fracture by causing a decrease in bone mineral density. It has also should be noted that in patients receiving corticosteroids, bone mineral density independent fracture risk increases. Furthermore, now we are aware of the existence of many diseases including type 2 diabetes, which contributes to an increase in the risk of fracture irrespective of bone mineral density. Unfortunately, at present, it is difficult to quantitatively evaluate the contribution of those background diseases to fracture risks, so the establishment of guidelines on intervention for fracture prevention is still awaited.