15.03 Drugs used to treat osteoporosis and other bone disorders

Osteoporosis is a skeletal disorder with compromised bone strength, and increased risk of fracture. Osteoporosis is common in people who are ³ 50 years old, with 1:2 women and 1:8 men having a fracture caused by osteoporosis.

The causes of osteoporosis are multiple with physical, hormonal (predominantly low levels of oestrogens) and nutritional factors acting alone or together. The risk factors for osteoporosis are increasing age, being female, oestrogen deficiency, White race, low weight, family history, lack of exercise, alcohol abuse and smoking (especially in men).

Primary osteoporosis often follows menopause in women, and occurs later in men. Secondary osteoporosis is a result of medication, mainly glucocorticoids. Osteoporosis is often described as a silent disease because initially there are no symptoms. But eventually, it leads to stooped posture, loss of height (1-2 inches due to multiple compression fractures of the spine), back pain and fractures. About half are spinal, a quarter is hip and a quarter is wrist fractures.

The diagnosis of osteoporosis is by measuring Bone Mineral Density, BMD, and when BMD is 2.5 SDs below mean for young adult women, osteoporosis is diagnoses. BMD is measured by DEXA (dual X-ray absorptiometry) which is scans of the spine, hip and arm to measure bone density