心臟病及保健 Heart Disease And Health http://心臟病.tw www.heartdisease.idv.tw
Andrew Ying-Siu Lee, MD,PhD.
Osteoporosis means low bone mass and microarchitectual deterioration of bone tissue leading to bone
fragility and susceptibility to fracture. It commonly affects vertebral, hip and wrist bones. The most devastating
hip fracture causes 5-20% mortality within 1 year and >50% incapacitated. Other symptoms include: chronic
back pain, humpbacked, difficulty in breathing etc.
Risk factors of osteoporosis include: Age, low BMD, female gender, history of fragility fracture,
history of parental hip fracture, low body weight, severe immobility, lifestyle (smoking, alcohol),
diseases (rheumatoid arthritis, osteoarthritis, endocrine disease, chronic obstructive pulmonary
disease, diabetes mellitus, chronic renal failure etc.).
Dignosis of osteoporosis is usually measurement of bone mineral density BMD (T score) by
dual X-ray absorptiometry, as below:-
Classification of osteoporosis
nNormal bone mineral density (BMD) not more than 1 standard deviation (SD)
below young normal adult mean (T score > -1)
nOsteopenia BMD 1 – 2.5 SD below (T score -1 to –2.5)
(low bone mass)
nOsteoporosis BMD > 2.5 SD below (T score < - 2.5)
nSevere osteoporosis osteoporosis with fragility fracture
Therapy of osteoporosis include: exercise, calcium and vitamin D supplementation, nasal spray
calcitonin (inhibit osteolysis), biphosphonates (inhibit osteolysis) and parathyroid hormone (activate
bone cell activity and increase bone density).