Lecture 14 - Osteoporosis Flashcards
Define osteoporosis
“porous bone” - chronic skeletal disorder of compromised bone strength associated with low bone density (quantity) and deterioration of bone microarchitecture (quality) which often results in fragility fractures
What 2 things does bone strength depend on?
1) bone mass (a quantity indicator measured as BMD)
2) bone microarchitecture (measure of quality)
What factors increase bone resorption > formation?
menopause
aging
disease
drugs
peak bone mass occurs when?
mid 30’s
bone loss accelerates at ____
menopause
OP is known as the ____ ____
silent thief
OP: describe it
slowly steals bone density over many years without signs of symptoms until a bone breaks or fractures
(1/3 women and 1/5 men over 50 will suffer an OP fragility fracture)
What is a compression fracture?
loss of > 25% vertebral height with end plate disruption
*compression fractures in the spine can cause losses of 6-9 inches in height
List some consequences of fractures
- increased incidence of additional fractures
- chronic pain
- immobility
- decreased quality of life
- loss of independence
- institutionalization
- cost to healthcare
- death (esp after hip or spine fracture)
What is the most serious consequence of OP?
fragility fractures (diagnosed by x-rays)
Fragility fractures occur ____ or from ____ _____
spontaneously or from minor traumas
What are the common sites for fracture
hip, spine, wrist
Describe the OP assessment:
- Assess for fractures (diagnosed by x-rays)
- Bone Mineral Density (BMD) is assessed by DXA (dual x-ray absorptiometry) at the hip and spine
- WHO classification of OP based on BMD is a T-score < -2.5
- BMD correlates with fracture risk but is only ONE component
see slide 8 and 9
ok
Can BMD (bone mineral density) alone determine fracture risk?
no - Bad result needs to be incorporated into a fracture risk calculator
Candidates for Osteoporosis Therapy:
Decision to treat is independent of ______ result based on _____ _____
BMD
fracture history
Candidates for Osteoporosis Therapy:
Based on fracture history
- If had fragility fracture of the hip
- If had fragility fracture of the spine (66% are asymptomatic)
- If had > 2 non-spine, non-hip fragility fractures
- If had 1 non-spine, non-hip fragility fracture after age 40 AND prolonged glucocorticoid use in the previous year
Who else is a candidate for Osteoporosis Therapy:
- all men or women at high fracture risk should receive treatment
- those at moderate risk may need treatment (depends on presence of other risk factors)
- those who are deemed low risk do not treat treatment with OP medication
Exercise and fall prevention
- strength training 2x/week
- balance training or tai chi daily
- > 30 min aerobic physical activity daily
- walking is NOT enough without strength or balancing training
- encourage attention to posture and exercises for back extensor muscles daily
- hip protectors, home safety assessment, reassess meds
Recommended calcium for > 50 yrs old
1200 mg daily
Recommended calcium for 19-50 yrs old
1000 mg daily
Vitamin D recommended for adults under age 50 without OP or conditions affecting absorption ?
400 to 1000 IU daily
Vitamin D recommended for adults over 50 ?
800 to 2000 IU daily
*if they require > 2000 IU daily, monitor serum 25-OH D levels
List some other recommendations for basic bone health
- Quit smoking
- Limit alcohol to < 2 beverages per day
- Follow Canada’s food guide: adequate protein intake, keep sodium intake < 2300 mg/day
What types of medications can increase the risk of falls?
Meds taken for:
- Sleep
- Mood/behaviour
- Anxiety
- Depression
- Hypertension
- Allergies
- Pain
- Muscle spasms
*these meds may impair balance, co-ordination, vision, may cause drowsiness, dizziness, hypotension, may increase confusion and forgetfulness
What regulates serum calcium levels?
tb to mechem
calcitonin and parathyroid hormone (PTH)
(Calcitonin decreases and PTH increases serum Ca concentration)
300 mg Ca in ??
250 mL milk
3/4 cup of plain yogurt
245 mg Ca in ??
3 cm cube cheese
Calcium supplements:
Less than or equal to ____mg Ca per dose maximizes absorption
500
Calcium supplements:
List some things about Calcium carbonate
widely available, cheap, must be taken with a meal for optimal absorption, may be associated with more GI complaints
Calcium supplements:
List some things about Calcium citrate
can be taken with or without meals, recommended if patient on PPI or H2 blocker, may be option for those unable to tolerate CaCO3
Why is Vitamin D important?
- Helps body absorb & use calcium/phosphorus to build/maintain strong bones & teeth; can help protect older adults against OP; improves immune function
- Vitamin D supplementation has been shown to reduce falls in elderly
Vitamin ___ (cholecalciferol) is synthesized in skin on exposure to UVB light from sun and is found in fish, meat, egg, fortified food and milk products and several plant species
D3
Vitamin __ (ergocalciferol) is found in wild mushrooms, fungi and yeasts
D2
Vitamin D2 and D3 must be converted to the active form in the ____ and ______
liver and kidneys
What does low serum vitamin D result in? (<30 nmol/L)
- increased calcium resorption from bones
- associated with balance problems, high fall rates, low Bad and muscle weakness
What does excess vitamin D result in? (>250 nmol/L)
-hypercalcemia and increased calcium depositions in body and cause calcification of kidney, heart, lungs and blood vessels
Sources of Vitamin D?
fatty fish, egg yolks, milk/fortified food and beverages