What condition is characterized by decreased bone density and increased fracture risk?

The condition characterized by decreased bone density and an increased risk of fractures is osteoporosis. This disease results from an imbalance between bone resorption and bone formation, leading to the weakening of bones. As bone density decreases, the structural integrity of the bone is compromised, making it more susceptible to fractures even from minor falls or injuries.

Osteoporosis is often described as a silent disease because it may progress without symptoms until a fracture occurs, commonly in areas such as the hip, spine, or wrist. Risk factors for osteoporosis include age, gender (with women being at higher risk post-menopause), family history, low body weight, and certain lifestyle factors such as smoking or excessive alcohol consumption.

In contrast, other conditions listed, such as arthritis, primarily affect joint function and mobility rather than bone density specifically. Osteomalacia involves softening of the bones due to vitamin D deficiency but does not primarily result in low bone density. Paget's disease of bone typically results in enlarged and deformed bones rather than decreased bone density throughout the skeleton.