a. What is it ?
Osteoporosis is a disease that affects the entire skeleton. This disease is characterized by a reduction in bone mass and a alteration of bone tissue structure. These alterations lead to a reduction of bone strength which, ultimately, results in an increased risk of fractures. It has to be noted that menopause and its consequence, the drop of estrogneous hormone production, constitute one of the significant major risk factor implicated in the process of bone degradation.
b. Is it severe ?
The most frequent osteoporotic fractures are those of the spine (vertebral fractures) and of the hip (particularly femoral neck fractures). Rib or wrist fractures are also common. Clinically, fractures are classified as vertebral or non-vertebral. In women as well as in men and for all fractures, it results in a significant increase of morbidity, a significant loss in quality of life et partial fonctionnal physical limitation in daily life. Furthermore, one may notice an increase in mortality (which is 20% to 25% higher in presence of hip fracture). On the top of these observations, it may be underline that the loss of quality of life and the increase of the mortality is the most proeminent during the first year after the occurrence of fracture event.
c. Is it frequent ?
Switzerland is among the countries with high risk of osteoporosis. At the age of 50, on average, the probability to develop an osteoporotic fracture during life is 51.3% for women and 20.2% for men. The yearly rate of new fracture (incidence) in postmenopausal women is 486/100 000/yr., while it is 243/100 000/yr. for men over 50. In addition, with age, incidence of osteoporotic fracture increases among the postmenopausal women, from 121/100 000/yr. at the age of 50 to 1537/100 000/yr. at the age of 80-85 years old. Incidence of hip fracture is 621/100 000/yr. in women over 50 and of 232/100 000/yr. in men over 50. Finally, incidence of hip fracture increase exponentially with age as well.

Therefore, osteoporosis represents a pathological condition frequent and severe for which the best prevention should be offered.