Bone Abstracts

Osteoporosis in premenopausal is dominated by secondary causes, among which anorexia nervosa, the female athletic triad, celiac disease, and glucocorticoid-induced osteoporosis (GIO) constitute the most frequent conditions. Stress fractures of the lower extremities and low energy fractures of the ribs, are also frequent. Various genetic causes like osteogenesis imperfecta tarda are probably underdiagnosed and various inflammatory conditions also play a role. A rare, but often severe form is pregnancy-associated osteoporosis with multiple fractures of the spine and transient osteoporosis of the hip, the causes of which are still unknown. A large group of young women are considered for treatment due to osteopenia, but due to the lower risk of fracture and high NNT in this population, most guidelines agree that specific osteoporosis treatment is only indicated if low energy fractures are demonstrable or risk estimates (e.g. using FRAX) show very high probability of fracture over the next 10 years.

Also in young males secondary causes mainly GIO alcohol abuse, hypogonadism, celiac disease, and malignancy dominate. A subgroup of males, however, show no secondary causes and are classified as idiopathic osteoporosis. Usually they present with very low bone mass and multiple spine fractures. Histomorphometry analysis usually shows a low turnover osteoporosis. The etiology is, however, still poorly defined. A subgroup of males also present with multiple stress ad rib fractures.

The treatment options in these age groups are mainly sex hormone replacement and bisphosphonates. I.v. bisphosphonates constitute an attractive option, because they often can be given every second year, thus limiting exposure during long-term treatment. Anabolic therapy with PTH should be reserved for severe cases but a more liberal prescription practice in younger people is probably warranted.