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Flashcards in Osteoperosis Deck (33)
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1
Q

Rickets/Osteomalacia (2)

A

Vitamin D deficiency leading to softening of bones

Because of inadequate bone mineralisation

2
Q

Why do osteoporotic fractures increase during winter?(2)

A

Lower sunlight exposure

Reduced vitamin D synthesis

3
Q

Osteoporosis (3)

A

Low bone mass
Deterioration of bone tissue
High risk of fracture

4
Q

Alcoholism (4)

A

Suppresses proliferation of osteoblasts which inhibits born formation
May increase osteoclastogenesis
Reduced bone mineral density
Increased risk of falling

5
Q

Reproductive cycle and risk of osteoporosis

A

Early menopause or late menarche increase risk

6
Q

Types of bone material (2)

A

Cortical

Trabecular

7
Q

Most common bone material

A

Cortical (70-80%)

8
Q

What is the majority of skeleton made from?

A

Inert matrix materials

9
Q

Inert matrix materials (3)

A

Calcium
Phosphate
Collagen fibres

10
Q

When does the deposits of matrix occur?

A

Childhood

11
Q

What is peak bone mass?

A

Maximum bone mineral mass attained

12
Q

Role of osteoblasts

A

Bone mineral deposition

13
Q

Role of osteoclasts

A

Bone mineral loss

14
Q

Growth hormone

A

Increases osteoblasts

15
Q

Vitamin D3 effects (5)

A

Increases calcium absorption
Increases calcium uptake
Increases calcium bone deposition

Also increases osteoclasts
Results in calcium bone loss

16
Q

Calcitonin

A

Inhibits osteoclasts

17
Q

Sex steroids

A

Increases osteoblasts

Increased deposition

18
Q

Parathyroid hormone (4)

A

Inhibits sex steroids (prevents osteoblasts)

Increases osteoclasts
Bone loss
Calcium bone loss

19
Q

______ bone remodels ____ times faster than _____ bone

A

Trabecular
8
Cortical

20
Q

Which bone regions are more vulnerable to bone loss?

A

Trabecular

21
Q

Role of VDR (2)

A

Role in controlling calcium status

Variants linked to lower BMD

22
Q

Oestrogen receptor (2)

A

Key role in oestrogen effects on bone tissue

Variants may be linked to BMD

23
Q

Collagen 1 alpha 1 gene (2)

A

Collagen 1 alpha is the main protein in bone

Abnormal gene forms may alter bone and reduce strength

24
Q

What percentage of gene variation may related to BMD

A

60-90%

25
Q

Importance of childhood

A

Maximising peak bone mass

26
Q

Importance of young adulthood

A

Maintain bone mass

27
Q

Importance of older adulthood

A

Minimise bone loss

28
Q

Calcium (4)

A

Benefits bone health at any stage
Higher intakes increase bone mass
However does but reduce the risk of fractures
Benefits of supplements disappear rapidly once supplementation ends

29
Q

Effects of vitamin D supplementation (2)

A

Reduces risk of fractures at high doses

Slows bone mineral loss in individuals with low calcium status

30
Q

Caffeine and BMD (5)

A

Associated with lower BMD

Promotes excretion of calcium

Reduced calcium uptake from gut

In post menopausal women high intakes may be related to increased risk of fractures

VDR genotype dependent

31
Q

Phytoestrogens (5)

A

Plant derived agents with similar structure to steroids
Can bind to oestrogen receptors and produce biological effects
May be safe alternative to HRT post menopause
May prevent bone loss in women
However studies have shown little effect

32
Q

Equol (4)

A

Produced by gut microflora after consumption of phytoestrogens
Depending on phenotype
This conversion more prevalent in vegetarians
Has enhanced effects at oestrogen receptors

33
Q

Protein and osteoporosis (4)

A

Excessively high intakes may promote calcium excretion and bone loss
Protein promotes muscle strength and reduces risk of falls
Moderate intakes increases BMD depending on calcium status
However elderly are at the greatest risk of PEM in developed countries