Osteoporosis

Osteoporosis is a common disease characterised by a generalised reduction in bone mineral density (BMD), microarchitectural deterioration of bone tissue and an increased risk of fracture. Since BMD values fall progressively with age, the prevalence of osteoporosis increases with age. It has been estimated that approximately 50% of all women will have osteoporosis by the age of 80. Studies in twins and families indicate that genetic factors play an important role in the regulation of BMD and other determinants of osteoporotic fracture risk. Osteoporosis is a polygenic disorder, determined by the effects of several genes, each with relatively modest effects. Population-based studies and case-control studies have similarly identified polymorphisms in several candidate genes that have been associated with bone mass or osteoporotic fracture, including the vitamin D receptor, oestrogen receptor and collagen gene. Bisphosphonates, and in some patients denosumab, are first-line drugs for osteoporosis.