Pathophysiology and treatment of osteoporosis: challenges for clinical practice in older people

Abstract

Osteoporosis, a common chronic metabolic bone disease is associated with considerable morbidity and mortality. As the prevalence of osteoporosis increases with age, a paralleled elevation in the rate of incident fragility fractures will be observed. This narrative review explores the origins of bone and considers physiological mechanisms involved in bone homeostasis relevant to management and treatment. Secondary causes of osteoporosis, as well as osteosarcopenia are discussed followed by an overview of the commonly used pharmacological treatments for osteoporosis in older people.

Keywords: Bone development; Older People; Osteoporosis; Osteosarcopenia; Pathophysiology; Treatment.

Fig. 1

Remodelling cycle and regulators of bone formation. The bone remodelling cycle occurs in 5 stages—activation (during which osteoblastic expression of M-CSF and RANKL stimulate osteoclast progenitor maturation and differentiation into osteoclasts), resorption of bone (by osteoclasts), reversal, formation (new bone laid down by osteoblasts) and termination (bone returns to quiescent phase). Bone remodelling is stimulated by calcitriol and PTH and is inhibited during the quiescent phase by sclerostin, which inhibits WNT driven bone formation and OPG which inhibits RANK-RANKL interactions

Fig. 2

Actions of glucocorticoid excess on bone