Osteoporosis Flashcards
what is it?
progressive systemic skeletal disease characterised by low bone mass and micro-architectural deterioration of bone tissue with a consequent increase in bone fragility and susceptibility to fracture
who gets it?
it is very common in the UK
due to an increase in fracture risk - hip fractures and vertebral fractures are more common and cause the greatest inpatient stays
far more common in women
what medication can increase osteoporosis likelihood?
corticosteroids -
reduce osteoblast activity and lifespan suppression of replication of osteoblast precursors, reduction in calcium absorption and inhibition of gonadal and adrenal steroid production
most rapid loss is in the first 6 months
what are the secondary causes of osteoporosis?
endocrine - hyperthyroidism, hyperparathyroidism, Cushing’s disease
Gastrointestinal e.g. coeliac disease, IBD, chronic liver disease, chronic pancreatitis
Respiratory - CF, COPD
Chronic kidney disease
how does it present?
increased fracture risk particularly in over 50s
osteoporotic fractures cause pain, disability and death
common fracture sites
- neck of femur
- vertebral body
- distal radius
- humeral neck
hip fractures can be very debilitating - 50% of people can’t liv independently afterwards
vertebral body fractures can affect breathing and abdominal issues because of the shrinking space - causing the hunched over appearance
can take more than one fracture because diagnosis sometimes it isn’t caused by a trauma just cough or rolling over or something
guidelines for osteoporosis
assessed on fracture risk rather than bone mineral density
fracture risk - people at risk of a low trauma fracture (things which shouldn’t break a healthy bone e.g. falling from standing)
what are the risk factors for fragility fractures?
Non modifiable - age - gender - ethnicity - previous fracture - family history - menopause <45years - co-existing disease Modifiable - BMD (bone mineral density) - alcohol - weight - smoking - physical inactivity - pharmacological risk factors - e.g. try to reduce steroids
calculators of fracture risk
- Qfracture, WHO fracture risk calculator
- Assess anyone >50 with risk factors and anyone under 50 with early menopause or on glucocorticoids
what investigations should be done?
DXA scan do when there is:
- 10 year risk of an osteoporosis fracture is at least 10% from risk factor calculators
- Patients over 50 with low trauma fracture
DEXA scans measure bone mineral density
- normal: BMD within 1 SD of the young adult reference mean
- Osteopenia (low bone mass): BMD >1 SD below the young adult mean but <2.5 SD below this value
- Osteoporosis: BMD >2.5 SD below the young adult mean
- severe osteoporosis: BMD > 2.5 SD below reference mean and fragility fracture
if under 20 only z score reported (the comparison with a aged matched mean
how is it managed?
lifestyle advice diet pharmacological - calcium and vitamin D supplements - bisphosphates - zoledronic acid - denosumab - teriparatide - romosozumab HRT SERMS (selective estrogen receptor modulators) testosterone
what lifestyle advice helps manage osteoporosis?
high intensity strength training low-impact weight-bearing exercise (standing, one foot always on the ground) avoidance of excess alcohol avoidance of smoking fall prevention
recommended diet for osteoporosis management?
RNI 700mg calcium (2-3 portions of dairy food groups)
Postmenopausal women aim dietary intake 1000mg calcium per day to reduce fracture risk (3-4 portion calcium rich foods)
non-dairy
- bread and cereals (fortified)
- fish with bones, nuts
- green vegetables, beans
what do calcium and vitamin D supplements do for osteoporosis?
to help with underlying deficiency
if low exposure to sun but good dietary calcium - vitamin D only supplement
calcium supplements can’t be taken within 2 hrs of oral bisphosphate
what do bisphosphates do for osteoporosis?
1st line drug treatment
Anti-resorptive agents – alendronate and risedronate
Prevent bone loss at all sites vulnerable to osteoporosis
Reduce risk of hip and spine fracture
They are adsorbed onto the bone surface as analogues of pyrophosphate and are then ingested by the osteoclasts which leads to cell death and thereby inhibits bone resorption – they also fill In the reabsorption sites which increases bone strength
For people with T score less than -2.5 and existing fragility fracture 30 or people with a steroid requirement >7.5mg prednisolone for 3 months or more or if there is a prevalent vertebral fracture, consider treatment with T score < -1.5
5 year therapy – 10 years if vertebral fracture (consider bone holidays)
Long term risks – osteonecrosis of the jaw, oesophageal malignancy and atypical fractures
what does zoledronic acid do for osteoporosis?
2nd line
once yearly IV infusion for 3 years
effects remain for 3 years after the infusions are stopped then the cycle can be restarted
Good for people with GI
More effective for vertebral fractures than oral bisphosphate
what does teriparatide do for osteoporosis?
it is an anabolic agent - causes bone formation as a recombinant parathyroid hormone
expensive so saved for very severe - people who have ad low trauma vertebral fractures
recommended to reduce the risk of vertebral and non-vertebral fractures in postmenopausal women with severe osteoporosis
recommended over oral bisphosphate in postmenopausal women with at least 2 moderate or 1 severe low trauma vertebral fracture to prevent further vertebral fracture
