Module 4.2 (Osteoporosis) Flashcards
What is the definition of osteoporosis?
A disease characterised by low bone mass
and micro-architectural deterioration of
bone tissue leading to enhanced bone
fragility and consequent increased fracture
risk
A skeletal disorder characterised by
compromised bone strength predisposing to
an increased risk of fracture
What are the 4 types of osteoporosis?
- Most common – related to aging
- Secondary osteoporosis -> Potentially reversible
- Osteoporosis imperfecta
- > Rare form possibly present from birth - Idiopathic juvenile osteoarthritis -> Occurs in children aged 8 to 14 years
What is the difference between osteoblasts and osteoclasts?
Osteoblast: produce collagen and other matrix proteins
Osteoclast: resorb bone
Osteocytes: mature osteoblasts, line bone surface -> become embedded in bone matrix
How is osteoporosis diagnosed?
diagnosis is based on
>fracture after minimal trauma
>detection of low bone mineral density (BMD)
-> the lower the BMD -> the higher the fracture risk
A number of methods can be used to determine BMD.
Gold standard = dual x-ray absorptiometry (DXA) in a facility with high quality control.
>measurements of BMD done in the hip and spine.
Who should have a DXA scan?
Patients >50yrs with risk factors
Patients with a minimal trauma fracture
Suspected vertebral fracture
Patients >70 years
How does the T score indicate BMD results?
-1 or higher Normal BMD
Between -1 and -2.5 Osteopenia
-2.5 or lower Osteoporosis
The number of standard deviations a persons’ BMD, at any major skeletal site, deviates from the young adult mean for the same sex
How does the Z score indicate BMD results?
The number of standard deviations a person’s BMD is from the age and sex-matched mean BMD
>useful to assess patients <50 years (in addition to T-scores)
>useful to assess possible secondary osteoporosis
>low z-score (less than -2) indicates abnormal bone loss
What are clinical risk factors for osteoporosis?
Clinical risk factors include:
Constitutional factors (non-modifiable)
Diseases and drugs (modifiable)
Lifestyle and nutrition (modifiable)
Absolute risk can be calculated using internet-based calculators including:
Garvan assessment tool
FRAX assessment tool
IOF risk assessment tool (not numerical)
What are constitutional risk factors?
Female sex n
Post menopause/ early menopause n
Ageing n
Late menarche
Family history of osteoporosis n
Caucasian/Asian race n
Short stature n
Previous lowtrauma fracture
What are some disease risk factors?
Endocrine disorders
Mal-absorption syndromes
Chronic medical disorders
Low bodyweight and weight loss
RA & connective tissue disorders
What are some drugs that can cause bone loss?
Glucocorticoids
Excessive thyroid hormone
Antiepileptic drugs → especially those that are hepatic enzyme inducers
Glitazones
Long term heparin
Androgen deprivation therapy (prostate cancer)
Aromatase inhibitors (breast cancer)
Emerging evidence:
Long term high dose PPIs
SSRIs
What are some lifestyle and nutrition risks for osteoporosis?
Smoking
Excessive alcohol intake
Physical inactivity
Immobilisation
Low calcium intake
Vitamin D deficiency
True or False
>carbonated soft drinks may displace milk in the diet resulting in lower calcium intake
True → may lead to lower BMD indirectlyinnit cos not getting enough calcium
What are some factors that increase the risk of falls?
Chronic illness n
Balance, gait or mobility problems → parkinsons, stroke
Visual impairment n
Cognitive impairment → dementia
General deterioration associated with aging e.g. sarcopenia n
History of falls n Fear of falling n
Depression n
Blackouts/seizures n
Indoor and outdoor hazards n
Medications n
Physical inactivity n
Foot problems
What is the aim of the fracture risk assessment tool (FRAX)?
To identify people at risk of developing osteoporosis
>Model integrates clinical risk factors and BMD at femoral neck
>Helps clinicians decide if preventative measures are necessary
What is the aim of the Garvan Assessment tool?
To calculate bone fracture risk
>for use by GPs and other health professonals
>the calculator estimates both the 5 and 10 year risk of fracture based on
- age
- gender
- number of fractures
- number of falls
What is a major impact of osteoporosis?
A major feature of osteoporosis is fractures that occur following little or no trauma = minimal trauma fractures
Most common fractures in people with osteoporosis:
>weight bearing bones e.g spine, pelvis and hips
>bones that take the stress in falls e.g. wrists, forearm and upper arm
What is the impact of fractures?
Pain
Functional limitations and disability
Social isolation
Quality of life and mental health
Loss of independence
Mortality
What is some information about hip and pelvic fractures?
Associated with high levels of morbidity and mortality
In 2012-1698 deaths in Australia associated with hip/pelvic fracture
63% of deaths were in patients >85 years and associated with falls
Info about wrist and foerarm fractures?
Associated with sudden force when person catches themselves in a fall n
Colles’ fracture n
Scaphoid fracture
Info about vertebral fractures?
- Most common type of spinal fracture in people with osteoporosis is called a wedge or compression fracture
- Usually occurs in the lower end of the thoracic region or the upper end of the lumbar region
- In this type of fracture, one or more of the vertebrae collapses forming a wedge shape
- A number of spinal compression fractures è characteristic bent forward hunched posture and loss of height (kyphosis)
Stats about
A) Hip fractures
B) Vertebral fractures
C) Wrist fractures
A)
90% occur in above 50 years old
80% occur in women
>most devastating result of osteoporosis → patient admitted to hospital → disability + mortality → most occur after a fall
B)
¼ result from falls
C)
Most in women, 50% older than 65 years old.
What are some clinical risk factors that can be modified for osteoporosis?
Can take action to improve bone health at every stage of life
Modify clinical risk factors where possible
>stop smoking
>maintain an adequate food intake and ideal bodyweight
>ensure adequate calcium intake and Vit D concentration
>Reduce alcohol intake (≤ 2 standard drinks/day)
>Increase appropriate weight-bearing physical activity
>Consider whether osetrogen/progestin therapy is appropriate
>Be aware of increased risk for patients taking glucocorticoids
What diet for osteoporosis?
Adequate intake of foods containing calcium
E.g. dairy products, green leafy vegetables, fish with edible bones, tofu, chickpeas, almonds, dried figs and
>try to include 3 serves of dairy per day
- glass of milk (250mL)
- tub of yoghurt (200g)
- slice of cheese (40g)
Importance of calcium in osteoporosis?
Calcium is essential for building and maintaining bone
Calcium gives bones strength
Almost 99% of the body’s calcium is found in bones n
A small amount of calcium is in the blood and is essential for healthy functioning of the heart, muscles, blood and nerves n
Dairy food is the main source of calcium
Less than 50% of Aust. adults get their recommended intake of calcium
What is the recommended intake of calcium?
The BEST way to get calcium is from the diet
Osteoporosis Australia suggests 3-5 servings of calcium rich food per day
Calcium requirements depend on age an sex
Menopause is a time of moe rapid bone loss for women
Older adults absorb calcium less effectively
Other factors can influence calcium resorption
When to give calcium supplements?
If a person’s diet does not meet their daily calcium requirement a calcium supplement can be considered*
Need to consider the elemental calcium content of supplements
Considerations in counselling:
>effects on the absorption of other drugs
>differences in calcium salts (with or without food)
>common side effects e.g. bloating and constipation
>take supplement in the vening and dont take more than 500mg at a time of CaCarbonate
>calcium citrate better absorbed
Calcium supplements for prevention of osteoporosis?
Recommendation is to get calcium from diet n Where not possible – supplement dose = 500-600mg/day
Controversy over calcium supplementation and cardiovascular risk → Studies reported calcium supplements increased risk of MI by about 25% and stroke by 15-20%
Confusion and repositioning on advice about supplements
Excercise osteoporosis?
Weight bearing & resistance exercise → Important for improving bone density and helping to prevent osteoporosis
benefits of exercise
exercise maintains/improves
- muscle strength
- muscle mass
- flexibility
- motility
- balance
- ease of movement
THEREFORE reduced frequency and severity of falls
Effect of exercise on fracture risk → unclear
Caution - recommending exercise in patients with asymptomatic vertebral fractures
What type of exercise?
Important in all stages of life
Must be regular → at least 3x per week
Should progress over time → increase the challenge
routines should be varied
performed in short intensive bursts
exercise must be tailored to the patient
Consider what exercise you would recommend for a patient (female aged 63 years) diagnosed with osteoporosis who has had a previous fracture?
Patient with diagnosed osteoporosis
>combination of weight bearing exercise with supervised progressive resistance training and challenging balance and mobility exercises at least 3x per week
>avoid forward flexion and twisting of the spine as they can increase risk of spinal fractures
>moderate to high impact activities are only recommended for people with osteoporosis who do not have a previous fracture
Vitamin D osteoporosis? How is vitamin D absorbed into the skin?
Regulates calcium homeostasis & bone metabolism
For most Australians the main source of Vitamin D is from exposure to sunlight.
Vit D produced when skin is exposed to UVB light from the sun
The amount of sun exposure required to produce adequate levels of Vit D is relatively low
Sun exposure times required vary based on:
>season
>location in Australia
>skin type
>area of skin exposed
Many australians do not have adequate vit D
Sun exposure recommendations?
Is sunscreen use associated with lower Vit D levels?
Sunscreen prevents sunburn by blocking UVB light. Theoretically that means sunscreen use lowers vitamin D levels. But as a practical matter, very few people put on enough sunscreen to block all UVB light, or they use sunscreen irregularly, so sunscreen’s effects on Vitamin D might not be that important. An Australian study thats often cited showed no difference in vitamin D between adults randomly assigned to use sunscreen one summer and those assigned a placebo cream.
