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COMMONWEALTH OF AUSTRALIA
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Dr Kylie Williams
9351 6063
kylie.williams@sydney.edu.au

Briefly discuss the aetiology, epidemiology and
signs & symptoms of osteoporosis.

Describe prevention strategies for osteoporosis.

Discuss treatment options for osteoporosis.
A skeletal disorder characterised
by compromised bone strength
that increases risk of fracture.
NIH Consensus Development Panel on Osteoporosis Prevention, Diagnosis and Therapy, 2001

peak bone mass: by 30 years of age

cortical and trabecular bone 

menopausal trabecular bone loss 

women have 30% less bone mass than men

age
prevalence  with age


sex


women to men (4:1)
people with osteoporosis



4 / 5 don’t know they have it
3 / 4 with a fracture not treated
peak bone mineral density



WHO criteria (bone densitometry)




max. 3rd decade
genetic, environmental, lifestyle
normal: T-score > -1
low bone density: -1 - -2.5
osteoporosis: < -2.5
bone fractures



56% of women and 29% of men
significant morbidity and mortality
spine, hip, wrist fractures most common
Non-modifiable







gender
ing age
caucasian or asian
family history
small stature
low weight
early menopause or oophorectomy
Risk Factors
Modifiable

sedentary lifestyle/decreased mobility

decreased sun exposure

low calcium and/or Vitamin D intake

excessive alcohol consumption

cigarette smoking

predisposing medical factors: hyperparathyroidism,
Cushing’s syndrome

medications: corticosteroids, thyroxine, anticonvulsants, SSRIs

early: pain

pain precipitated by usual activities

restricted spinal movement

loss of height

curvature of the spine

dowager’s hump

fracture history

medical history

risk factors

indicators of bone turnover

bone mineral density scan:

dual x-ray absorptiometry (DXA)
www.sheffield.ac.uk/FRAX

maximise bone mass


calcium / vitamin D
weight bearing exercise

avoid or modify risk factors

prevent postmenopausal bone loss



calcium / vitamin D
? HRT
bisphosphonates, raloxifene, strontium
Hormone Replacement Therapy

prevention & treatment

prevents postmenopausal bone loss

benefit v risk1


 fractures
 breast cancer and cardiovascular events

oestrogen + progestogen if intact uterus

no longer widely recommended for primary
prevention of osteoporosis
1. Women’s Health Initiative Study, JAMA 2002;288:321-333
calcium
+
 vitamin D


HRT/tibolone

bisphosphonates

Selective oEstrogen Receptor Modulators

densoumab

teriparatide

strontium ranelate
Calcium

800-1000mg/day before menopause,
1200-1500mg/day after menopause

ideally from diet

carbonate or citrate

tablets vary in amount of elemental calcium

S/Es: gastrointestinal, hypercalcaemia

D/Is: calcitriol
bisphosphonates
iron, tetracyclines, quinolones
Vitamin D

deficiency   Ca++ absorption and  bone loss

 falls

cholecalciferol (vit D3) [ergocalciferol (vit D2)]



prevention of vitamin D deficiency
may  bone density &  risk of fracture
dose: 200 (5mcg) - 1000IU (25mcg) daily
cholesterol (diet)
provitamin D (skin)
vitamin D3 (cholecalciferol)
25-hydroxycholecalciferol
1,25-dihydroxycholecalciferol
Vitamin D

calcitriol

metabolite of vitamin D3

 bone density & ? risk of fracture

monitoring of calcium necessary

caution with calcium intake

hypercalcaemia: n & v, constipation, headache,
polyuria, thirst, apathy
Bisphosphonates
 1st line agents

bind to active bone remodelling sites and inhibit
bone resorption:  BMD,  fracture risk

alendronate


risedronate


10mg daily or 70mg weekly
5mg daily, 35mg weekly or 150mg monthly
zoledronic acid

5mg IV yearly

poor oral absorption (&  by food, Ca, Fe)

S/Es: GI; oesophagitis, oesophageal erosions/ulcers;
osteonecrosis of the jaw (ONJ)

D/Is: antacids, calcium, iron

counselling:


take first thing in the morning

take with a full glass of water

take at least 30 mins before food, drink, other meds

do not lie down for 30 mins
therapeutic effects last ~ 5yr after ceasing therapy
Raloxifene

selective oestrogen receptor modulator (SERM)

2nd line agent

beneficial effects:




adverse effects:



 bone density (< oestrogen, bisphosphonates)
improves lipid profile ( LDL)
 risk of breast cancer
 risk of venous thromboembolism
may aggravate hot flushes
60mg daily
New Therapies

Teriparatide - parathyroid hormone

promotes bone formation

20mcg sc daily

max. 18 months treatment

ADRs:
hypercalcaemia, nausea,
leg cramps, dizziness
New Therapies

Strontium ranelate

 bone resorption &  bone formation

2g at bedtime

ADRs:
nausea, diarrhoea, headache,
dermatitis, eczema;  risk of VTE
New Therapies

Denosumab

 bone resorption &  bone formation

60mg sc every 6 months

ADRs:
skin disorders, infections, pancreatitis,
ONJ, hypocalcaemia;
long term safety issues?

use lowest effective dose of corticosteroid

use topical or inhaled preparations when possible

maintain adequate calcium intake (diet or supplements)

bisphosphonates (prevention & treatment)

calcitriol (prevention)

modify risk factors eg alcohol, smoking, exercise, calcium

Osteoporosis Australia
www.osteoporosis.org.au

Prevent the next fracture: Pharmacist Guide

Calcium, Vitamin D and Osteoporosis: A guide for
Pharmacists
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