2. Bone metabolism disorders

Question 1

What is osteoperosis?

Answer 1

Characterised by low bone mineral density and the risk of fractures

Question 2

Osteoperosis risk factors

Answer 2

• Post-menopausal women due to their declining oestrogen levels
• 50+ men
• Patients on a long term corticosteroid
• Elderely
• vitamin D and calcium D deficinecy
• Diabetes
• Fractures at site characteristic of osteoperosis
• Low bMI, smoking, no exercise, alcohol

Question 3

Osteoperosis treatment

Answer 3

1st line: oral bisphosphonates (alendronic acid and risedronate). Can be taken long term for 5 years before requring a review

Also taken by patients on large doses of corticosteroids as prevention (≥7.5mg daily prednisolone or equivalent) who are at high risk of having a fracture
To qualify for prevention:
- men 70+ & previous fragility fracture
- women 70+ OR previous fragility fracture

In post-menopausal women
HRT is given INSTEAD to prevent osteoperosis. Only given to women <60 years with menopausal symptoms

Other bisphosphonates include: ibandronic acid, zoledronic acid

Question 4

Bisphosphonates mechanism of action

Answer 4

Prevents the bone from being dissolved by osteoclasts and slows down the rate of bone resorption but in doing so, also prevent new bone formation

Question 5

Alendronic acid counselling

Answer 5

70mg once weekly

1) Swallow tablets whole
2) While sitting or standing
3) On an empty stomach at least 30min before breakfast or another oral medicine
4) and to stand or sit upright for 30 minutes after

Question 6

Risedronate counselling

Answer 6

35mg once weekly. Can be taken anytime of day except at bedtime or before rising

1) Leave 2 hour gap between food and drink, calcium products, anatacids, iron or minerals

2) Should stand or sit upright for 30 minutes

Question 7

Bisphosphonate side effects

Answer 7

• Oesophageal reactions (patients must report signs of dysphagia, worsening heartburn, pain on swallowing) !
• Atypical fermoal fractures (patients must report thigh, hip or groin pain) !
• Osteonecrosis of the jaw (patients must report dental mobility, pain, swelling, ulcers)
• Osteonecrosis of the auditory canal when bone cells of the audiory canal begin to grow (patients must report ear pain, discharge, chronic infections, cholesteatoma)