OSTEOPOROSIS

Question 1

What is OP?

Answer 1

Systemic skeletal disease characterised by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture.

Question 2

Describe the pathophysiology of OP

Answer 2

• Bone mass peaks at about 38 for men and women.
• Bone mass then drops off at around 50 for women (menopause) and 53 for men (normal ageing).
• This results in an increase in fracture risk.
• Women are more likely to get fractures.
• Common fractures include hip, vertebral and Colles’.

Question 3

What are the risk factors for OP?

Answer 3

• Gender
• Age
• Previous Fracture
• family history
• alcohol
• smoking
• Ethnicity (caucasian and asian more likely)
• Postmenopause
• Inflammatory Disease e.g RA, IBD
• Endocrine Disease
• Drugs e.g steroids

Question 4

What endocrine diseases can cause osteoporosis?

Answer 4

• Hyperthyroidism/Primary hyperparathyroidism
• Cushing’s syndrome
• Early menopause/Male hypogonadism

Question 5

What are the signs of osteoperosis?

Answer 5

• Dowager’s hump (crush fractures of vertebrae) if trabecular bone is affected
• Fractures (esp hip) if cortical bone is affected

Question 6

What are the investigations for osteoporosis?

Answer 6

• X ray (normally in hindsight after a fracture) - insensitive for detecting osteopenia
• DEXA scan–> T score
• Consider specific investigations for secondary causes if suggestive history

Question 7

What are the complications of OP?

Answer 7

Morbidity in first year post hip fracture

• Death within 1 year: 20%
• Permanent disability: 30%
• Unable to walk independently: 40%
• Unable to carry out at least one independent activity of daily living: 80%

Question 8

What is used to assess risk of osteoporotic fracture in 10 years for untreated patients?

Answer 8

FRAX Tool

Question 9

What is the non-pharmacological treatment of OP?

Answer 9

• Stop smoking and reduce alcohol
• Weight bearing exercise may increase bone mineral density
• Balance exercises such as taichi reduce risk of falls
• Calcium and vitamin D rich diet (use supplements if diet insufficient)
• Home based fall prevention programme (with visual assessment and home visit)

Question 10

What is the pharmacological treatment of OP?

Answer 10

Anti-resorptive-decreases osteoclast activity and bone turnover:

• Bisphosphonates
• HRT
• Denosumab

Anabolic-Increase osteoblast activity and bone formation:
-Teriparatides

Question 11

How do bisphosphonates work?

Answer 11

-First line treatment
-Inhibits osteoclast activity and reduces risk by 50%
-Oral
Alendronate (daily / weekly) (first line)
Risedronate (daily / weekly)
Ibandronate (monthly)
Etidronate (2 weeks of 13)
-IV
Ibandronate (3 months)

Question 12

What are the benefits of HRT?

Answer 12

• Reduce the risk of fractures by about 50%
• Stop bone loss; bone density may increase by up to 10%
• Prevents hot flushes and other menopausal symptoms
• Reduces risk of colon cancer

Question 13

What are the risks of HRT?

Answer 13

• Breast cancer
• Stroke
• Cardiovascular disease
• Venous thrombo-embolic disease
• Vaginal Bleeding

Question 14

How does denosumab work?

Answer 14

• Monoclonal antibody to RANK ligand
• Rapid acting and very potent anti-responsive
• Good fracture risk reduction
• Rebound increase of bone turnover when stopped
• Given sc twice yearly

Question 15

How does teriparatide work?

Answer 15

• PTH analogue
• First anabolic treatment
• Reduce the risk of fractures by more than 50%
• Increases bone density by up to 20%
• Expensive – reserved for cases that do not respond to other treatments
• Use limited to 24 months
• Contraindicated if history of bone cancer / metastasis or bone radiotherapy