Causes
• An imbalance between the creation and resorption of bone leads to osteoporosis. Non-
modifiable factors include genetic predisposition (e.g., *LRP5* gene mutations), aging, and
menopause (e.g., estrogen depletion causing osteoclast activity). Smoking, excessive alcohol
use, sedentary lifestyles, and insufficient calcium and vitamin D intake are modifiable factors
that affect bone remodeling.
• Secondary causes include long-term conditions like rheumatoid arthritis and
hyperthyroidism, as well as drugs like proton pump inhibitors, which lower calcium
absorption, and glucocorticoids, which suppress osteoblasts. Hormonal abnormalities (such
as hyperparathyroidism) or prolonged immobility can cause weaken bones.
• Fracture risk is increased by several conditions, which also alter microarchitecture and
decrease bone mineral density. Prevention depends on the early detection of reversible
causes.