According to the WHO, what defines osteoporosis?

• A. T-score of -1.0 SD or below
• B. T-score of -2.0 SD or below
• C. T-score of -2.5 SD or below
• D. T-score of -3.0 SD or below

Answer: (C)

Osteoporosis is defined by the World Health Organization (WHO) as having a T-score of -2.5 standard deviations (SD) or below. The T-score is a measurement derived from a bone density test, comparing an individual's bone mineral density to the average peak bone density of a healthy young adult. A T-score of -2.5 SD indicates that the individual's bone density is significantly lower than normal and corresponds to an increased risk of fractures and other complications associated with weakened bones.

This definition sets osteoporosis apart from other conditions characterized by lower bone density. For example, a T-score between -1.0 and -2.5 SD indicates osteopenia, which is a less severe decrease in bone density and does not imply the same level of fracture risk as osteoporosis does. By adhering to the WHO's guidelines, healthcare providers can accurately diagnose osteoporosis and determine appropriate treatment strategies to help manage the condition effectively.