Osteoporosis Flashcards
Women lose up to __% of bone mass in the 5-7 years postmenopause
20
*~ 50% of women will experience an osteoporotic fracture in their lifetime
~50% of these women did not have osteoporosis defined by BMD
Describe the burden of hip fractures
- 24% mortality within first year
- 50% of hip fracture sufferers unable to walk without assistance
- 25% will require long term care
T/F?
A clinical diagnosis of osteoporosis can be made based upon a fragility fracture regardless of BMD status
True
*If they have a hx of a fragility fracture (fall from a regular height) then they can be dx with osteoporosis
What are factors contribute to bone strength
- Bone mass
- Bone turnover
- Bone quality
*-If you have an imbalance of one of these, then your bone strength is off
describe the pathophysiology of postmenopausal osteoporosis
With the onset of menopause (mid-forties or fifties), diminishing estrogen levels lead to excessive bone resorption that is not fully compensated by an increase in bone formation
**Theory: estrogen blocks cytokine secretion, resulting in decreased bone resorption
At menopause, estrogen goes down and OC activity increases and OB activity decreases= get more bone resorption
What are bone mass measurement devices
- central- qCT (not recommended for screening)
2. Dual-energy X-ray absorptiometry (DEXA)***
Who should BMD testing be performed on?
- Women 65+ years and men age 70* regardless of risk factors
Younger postmenopausal women and men aged 50-69 years with a risk factor: - Prior fragility fracture (before age 50)
- Use of a high risk meds
- FHX of osteoporosis
- RA or condition associated with increased bone loss
- Glucocorticoids 5mg+ daily for 3 or more months
- Current smoker
- Low body weight (<127 lbs)
- Initiating therapy for osteoporosis, on therapy for osteoporosis or discontinuing hormone replacement therapy
What are other risk factors for osteoporotic fx
- Small stature (<127 lbs)
- Personal history of fracture
- Premature Menopause
- History of amenorrhea
- Caucasian
- Advanced age
- Dementia
- Immobilization
- diet
- cig smoking/alcohol intake
- inactivity
- disease
what disease and meds can cause osteoporosis
disease: GI and anorexia
Meds: steroids, anticonvulsants, Depo-Provera
Describe te DXA process/ areas imaged
- Lumbar spine: L1-L4 (average)
- Hips: Femoral neck and total hip
Non-dominate forearm if:
- Spine instrumentation
- Spine fracture
- Severe degenerative disc disease
- Severe hip arthritis
- Hyperparathyroidism
How do you interpret T scores from DXA
WHO classification to determine normal, osteopenia, osteoporosis
Normal: -1.0 and above
Osteopenia: -2.5
Osteoporosis: -2.5 and below
Severe Osteoporosis: -2.5 and below w/ fracture
Describe what T and Z scores are
- T: Standard deviation difference between the patient’s BMD and a young-adult reference population
- Z: Standard deviation difference between the patient’s BMD and an aged-matched population
How do you interpret Z scores
Used to determine if further evaluation for secondary causes of osteoporosis is warranted
Steroids, Alcohol
Z-Score
What labs do you order for routine assessment of excluding secondary causes of osteoporosis
- CBC
- TSH
- 25-Hydroxyvitamin D
- 24-hour urinary calcium and creatinine clearance
- CMP: serum chemistries:
- calcium
- phosphorus
- creatinine
- alkaline phosphatase
- albumin
- liver enzymes
What are second level tests (nonroutine tests) for excluding secondary causes of osteoporosis?
- Markers of bone remodeling (Urine NTx, Bone specific alkaline phosphatase)
- Urine free cortisol
- ESR
- Intact parathyroid hormone (PTH)
- Anti-transglutaminase antibodies
- Serum and urine protein electrophoresis
- Bone biopsy
What is the FRAX (fracture risk assessment tool)
Introduced by WHO in 2008 in collaboration with the NOF
Goal: To identify patients at high risk of osteoporotic fracture
Estimates the 10-year probability of hip fracture or major osteoporotic fractures combined (hip, proximal humerus, distal forearm, spine)
What are the goals of osteoporsis prevention
- Maximize peak bone mass (usually reached by 30y/o)
2. Minimize rate of bone loss
What determines peak bone mass
60-70% due to genetic predisposition
30-40% due to diet, exercise, disease, medications
Non-pharmacologic therapies for osteoporosis prevention
- Calcium – elemental
- Vitamin D
- Weight-bearing exercise
- Habit Alteration (quit smoking and limit alcohol intake)
- Fall-prevention techniques
What is the optimal daily Ca2+ intake for women
> 50 years old (postmenopausal):
On estrogen: 1000-1200 mg
Not on estrogen: 1200-1500 mg
> 65 years old: 1200-1500 mg
*Calcium Supplements should contain Vitamin D– Some people take Tums for Ca2+ but there is no Vit. D so they are not absorbing it
Average adult needs ___ Vit. D units daily to maintain a 25-hydroxyvitamin D level at __ ng/ml.
800-1000
30
What is the managment recommendation for someone with 25-hydroxyvitamin D3 (total) <20 ng/ml
- Vitamin D 50,000 units
- Once weekly for 6-8 weeks–> 800-1000 units thereafter
- Recheck 25-hydroxyvitamin D in 3 months to access level
What is the managment recommendation for someone with 25-hydroxyvitamin D3 (20-30 ng/ml
- Vitamin D3 OTC- 800-1000 units daily
2. Recheck 25-hydroxyvitamin D in 3 months to access level
What is the recommendation of exercise for the prevention of osteoporosis
- 30 minutes of weight bearing exercise, at least 3 times weekly
- Normal growth, maintenance and remodeling of the skeleton depend on physical loading
- May aid in fall prevention by strengthening muscles which provide flexibility, balance and agility
