Osteoporosis

Question 1

What is osteoporosis?

Answer 1

Metabolic bone disorder leading to reduced bone mineral density

Question 2

What is the pathogenesis of osteoporosis?

Answer 2

Reduced osteoblastic activity -> low turnover

Reduced physical activity -> leads to decreased remodelling of bones

Might have poor nutritional status or hormones leading to decreased protection of bone minerals

Ultimately:
-disruption to balance between formation and resorption of bone leading to decreased mineral density of the bone -> compromising their structure

Question 3

What are the 2 major classifications of osteporosis?

Answer 3

Primary:
-age related osteoporosis
Eg post-menopause/senile/disuse

Secondary:
-associated with another condition or drug
Eg Hyperthyroidism/hyperparathyroidism/multiple myeloma/drugs

Question 4

What are the risk factors for developing osteoporosis?

Answer 4

SHATTERED

Steroid use >5mg prednisolone 
Hyperthyroidism/hyperparathyroidism
Alcohol 
Thin (BMI<18.5)
Testosterone decreased 
Early menopause 
Renal or liver failure 
Erosive/inflammatory bone disease (RA or myeloma) 
Dietary decreased Ca2+/ Diabetes mellitus T1

Question 5

Which drugs are associated with increased risk of osteoporosis?

Answer 5

Steroids

• reduce calcium absorption
• increase bone resorption

SSRIs

PPIs

Anti-epileptics

Anti-oestrogens

Question 6

Why is there an increased risk of osteoporosis post-menopause?
What might be adviced for post-menopausal women?

Answer 6

Oestrogen is protective against osteoporosis
-oestrogen promotes activity of osteoblasts i.e. acts to maintain the balance between bone formation and resorption

Might be given HRT = can be a source of oestrogen to enable the protectice effects after endogenous oestrogen production has stopped

Question 7

Why is hyperthyroidism a risk factor osteoporosis?

Answer 7

Hyperthyroid state can trigger imbalance of bone erosion due to increased stimulation of osteoclasts
I.e. leads to increased bone turn over and remodelling but with decreased bone mineral density= leads to brittle bones

Question 8

Why is hyperparathyroidism a risk factor for osteoporosis?

Answer 8

PTH acts to increase osteoclast activity to increase bone resorption to try and increase calcium levels

With excessive PTH there will be excessiove bone resorption due to osteoclast activity > osteblast activity and the loss of calcium and phosphate leads to bone demineralisation

Question 9

Which bones are typically effected in osteoporosis?

Answer 9

Verterbrae

-can lead to crush fractures of vertebrae leading to the characteristic appearance of some elderly ladies having Dowagers hump appearance

Question 10

What investigations can be done in someone suspected of osteoporosis?

Answer 10

Xray

DEXA scan- looks at bone density

Bloods to look at Ca2+/PO4+ and ALP

Question 11

What are conservative management options for osteoporosis?

Answer 11

Smoking cessation 
Reduce alcohol consumption 
Maintain healthy weight 
Adequate calcium and vitamin D
Home-based fall prevention 
Exercise and activity

Question 12

What pharmacological management is available for osteoporosis?

Answer 12

Bisphosphonates (1st line)
-interfern with osteoclast to reduce their activity

Calcichew-D3
-calcium and vitamin D combined

HRT
-for women in early menopause

Denosumab
-MAb blocking the acitivity of osteoclasts

Strontium ranelate
-stimulates osteoblasts and blocks osteoclasts

Raloxifene

• selective oestrogen receptor modulator
• stimulates oestrogen receptors on bones but not in breasts or uterus