Epidemiology of Osteoporosis and Fragility Fractures

According to the latest definition of osteoporosis, both bone mineral density (BMD) and bone quality are important in determining skeletal fragility fractures. Actually, a large proportion of fractures occur in people with BMD values indicating osteopenia or normal status. However, for epidemiological purpose, the prevalence of osteoporosis continues to be assessed on the basis of bone demineralization (2.5 Standard Deviations below the young adult mean values). Osteoporosis should not be regarded as a condition affecting exclusively women, as 20–25 % of hip fragility fractures occur in men, with a higher post-fracture mortality rate if compared to that recorded for females. All osteoporotic fractures should be considered as the first signal of an evolving diseases: fractures occurring at vertebra, forearm, humerus, ribs, feet, and hip are always associated with a higher risk of subsequent fragility fractures, and mortality (which is dramatically increased after hip fractures, up to 25 % at 1 year). A total of 20 % of people living in Western countries are thought to be affected by osteoporosis, with 4 million new fragility fractures occurring in Europe every year (including more than 800,000 hip fractures). Total direct costs of osteoporosis and related fractures are estimated to exceed 25 billion Euros in Europe and 18 billion Dollars in the United States. Medical expenditures are expected to double by the year 2050 based on the expected demographic projections. However, osteoporotic fractures represent even now an increasing problem in Asia and South America, with China, India, and Brazil accounting for 1 million of hip fractures. In this perspective, the World Health Organization (WHO) considers osteoporosis to be second to cardiovascular diseases as a critical health problem worldwide.