Recognizing and treating secondary osteoporosis.

Osteoporosis, through its association with fragility fracture, is a major public health problem, costing an estimated $34.8 billion worldwide per annum. With projected demographic changes, the burden looks set to grow. Therefore, the prevention of osteoporosis, as well as its identification and treatment once established, are becoming increasingly important. Osteoporosis is secondary when a drug, disease or deficiency is the underlying cause. Glucocorticoids, hypogonadism, alcohol abuse and malnutrition are among the most frequently recognized causes of secondary osteoporosis but the list of implicated diseases and drugs is growing and some of the more recently recognized associations, such as those with haematological conditions and acid-suppressing medications, are less well publicized. In some cases, advancement in treatment of the primary disease has led to people living long enough to develop secondary osteoporosis; for example, successful treatment for breast and prostate malignancies by hormonal manipulation, improved survival in HIV with the advent of anti-retroviral therapies, and improved treatment for cystic fibrosis. This Review emphasizes the importance of secondary osteoporosis, discusses familiar and less well-known causes and what is known of their mechanisms, provides guidance as to the pragmatic identification of secondary osteoporosis and summarizes treatment options, where available.