Osteoporosis Flashcards
1
Q
What is the main theme in regards to osteoporosis care?
A
Prevention!
2
Q
Define osteoporosis
A
- Loss of bone mass
- Loss of bone architecture
- Susceptibility to fracture
3
Q
What is the most common bone disease in humans?
A
Osteoporosis
4
Q
Where are the most common osteoporotic fractures?
A
Hip, vertebrae, and wrist
5
Q
What is a common reason for loss of height, pain, and kyphosis?
A
Vertebral fracture
6
Q
What are some of the effects of vertebral fractures?
A
- Can impact function (bending/reaching)
- Can impact lung/digestive function
7
Q
What are some psychological sequelae of osteoporosis?
A
- Anxiety
- Depression
- Body image
- Self-esteem impacts
8
Q
What are some quality of life sequelae of osteoporosis?
A
- Chronic pain management
- Disability
9
Q
What percentage of adult bone mass is acquired in childhood and adolescence?
A
90%
10
Q
At what age does bone mass peak?
A
- Age 19 in women
- Age 20.5 in men
11
Q
At what age does bone mass begin to decline?
A
- Age 40 in women
- Age 50 in men
12
Q
When does the most rapid bone loss occur in women?
A
Perimenopause
13
Q
What causes such a rapid bone loss in women in perimenopause?
A
Drop in estrogen levels
14
Q
What are some uncontrollable risk factors for osteoporosis?
A
- Age >50
- Female
- Menopause (especially early, before age 45)
- FH
- Low body weight/small & thin
- Caucasian/Asian
15
Q
What are some controllable risk factors for osteoporosis?
A
- Lifelong inadequate intake of calcium & vitamin D
- Not eating enough fruits and veggies
- Excessive ETOH
- Smoking
- Too much protein, Na, and caffeine
- Lifelong inactive lifestyle
16
Q
Describe the cortical portion of bones
A
- Dense, outer covering
- Mechanical strength & protection
17
Q
Describe the trabecular portion of bones
A
- “Spongy” bone/mesh-like
- Inside of long bones (especially at ends), vertebrae, pelvis
- Offers mechanical support
- More metabolically active
18
Q
What are the two continuous processes in bone remodeling?
A
Resorption and formation
19
Q
How often does the human skeleton regenerate itself?
A
Every 10 years
20
Q
What is the purpose of bone remodeling?
A
- Replace worn out or damaged bone
- Ensure oxygen & nutrient supply
21
Q
What are the 4 phases of bone remodeling and what is involved in each?
A
- Resorption (osteoclasts - cells that break down old bone)
- Reversal (prepping for deposition of bone - formation of “cement line”)
- Formation (osteoblasts - cells that synthesize bone matrix formation)
- Mineralization
22
Q
What is bone reabsorption?
A
- Resorption of bone tissue by osetoclasts & release of minerals
- Results in transfer of calcium from bone tissue to the blood
23
Q
What are osteoclasts?
A
Multi-nucleated cells that contain numerous mitochondria and lysosomes
24
Q
What are the 3 major players in regulation of bone remodeling?
A
- PTH
- Calcitrol (vitamin D)
- Estrogen
25
How does PTH maintain serum calcium?
- Stimulating bone resorption
- Increasing calcium reabsorption in kidneys
- Increasing calcitrol production in kidneys
26
How does calcitrol (vitamin D) maintain serum calcium?
- Increases intestinal calcium and phosphorus absorption to provide minerals needed for bones
- In cases of Ca & Phos deficiency, will stimualte bone resorption to maintain serum levels
27
How does estrogen maintain serum calcium?
- Inhibits bone resorption
- Increase in bone resorbing cytokines
- Can reduce bone formation directly through estrogen receptors on osteoblasts
28
How does calcitonin play a role in bone remodeling?
- Produced by thyroid gland
| - Inhibits osteoclasts/opposes PTH
29
How does thyroid hormone play a role in bone remodeling?
Stimulates both resorption and formation, causing increased turn-over
30
How do glucocorticoids play a role in bone remodeling?
Inhibit bone formation
31
What is the primary treatment goal of osteoporosis?
Prevention of fractures
32
What does the clinical evaluation for osteoporosis look like?
- PMH: risk factor assessment
- PE: Height assessment
- Lab tests as appropriate to look for secondary causes
- BMD testing with DXA
33
Who should we screen for osteoporosis, according to USPTF?
- Women 65+
- Women <65 with fracture risk =/> 65+ yo white woman w/o additional risk factors (>9.3%)
- No recommendation for men w/o previous known fx or secondary causes for osteoporosis
34
Who should we screen for osteoporosis, according to National Osteoporosis Foundation?
- All post-menopausal women 50+ should be evaluated for osteoporotic risk to determine need for BMD testing
- BMD testing via DXA for women 65+ and men 70+
- Postmenopausal women & men 50+ who have had an adult age fx to dx & determine degree of osteoporosis
- Low-trauma fx during adulthood
& Historical ht loss (current ht is 1.5in+ shorter than peak ht age 20)
& Prospective ht loss (current ht 0.8in+ shorter previously documented ht)
- Recent or ongoing long-term glucocorticoid tx - if bone density testing not available, vertebral imaging may be considered based on age alone
- Check for secondary cause of osteoporosis
35
What are some reasons to screen for bone density before age 65?
- PMH fragility fx
- Body weight <127lb
- Medical causes of bone loss, i.e. long-term glucocorticoid use
- 1st degree relative w/ hx hip fx
- Current smoker
- ETOH abuse
- Rheumatoid arthritis
36
How long does it take for glucocorticoid-induced osteoporosis to cause significant bone loss?
3 months
37
How many patients taking >7.5mg/dL of prednisone will fx?
50%, regardless of age or gender
38
What is DXA?
- Dual-energy x-ray absorptiometry (DXA)
| - Imaging usually done of lumbar spine and hip
39
To what does the T score on a DXA refer?
Findings compared to standards for healthy, younger adults of same sex and race
40
To what does the Z score on a DXA refer?
of standard deviations from the mean for people of the same sex, age, and race
41
What is the WHO DXA definition of osteoporosis?
- Normal = T score >/= -1
- Low bone mass = -2.5 to -1
- Osteoporosis = = -2.5
42
What is FRAX?
- Screening tool developed by WHO
- Calculates 10-yr probability of hip fx & 10-yr probability of major osteoporotic fx
- Specific to region & ethnicity
43
What are some uses of FRAX?
- Helpful in decision to tx for those with low bone density but not osteoporosis
- Helpful in deciding on DXA screen (YES if 10-yr risk >9.3%)
44
When is consideration of Z score helpful?
Younger people or when considering secondary osteoporosis
45
In what cohort would you be suspicious of secondary cause?
Osteoporotic fx or low Z score in younger post-menopausal women
46
What diagnostic tests would you consider if you are suspicious for secondary cause?
- CBC
- CMP (including LFTs)
- 24hr urinary calcium level
- 25-hydroxyvitamin D level
- TSH
Consider: PTH, celiac panel, serum protein electrophoresis, total testosterone/gonadatropin in younger men
47
Who do we treat pharmacologically?
Post-menopausal women/men age 50+ with
- Hip/vertebral fx (clinically or on imaging)
- T score = -2.5 at femoral neck,hip, or lumbar spine
- Low bone mass (-1.0 > T > -2.5) and 10-yr probability of hip fx 3% or greater or major osteoporosis-related fx 20% or greater based on US FRAX algorithm
48
How often should we rescreen with DXA?
q2yr after intiiation of tx and then not after if stable/improved
For women 65+ who are not tx:
- 10yr interval if T-score >-1.5
- 5yr interval if T-score -1.5 to -1.99
- 1-2yr interval if T-score -2.0 to -2.49
49
Diagnostic classification based on T-score
- Normal: >-1.0
- Osteopenia (low bone mass): -1.0 to -2.5
- Osteoporosis:
50
Indications for tx
- Personal hx of hip or vertebral fx
- T-score 3%)
- Risk of any major fx of 20% (FRAX)
51
Non-pharmacological interventions for low bone density/osteoporosis
- Adequate calcium & vitamin D
- Tx vitamin D deficiency
- Regualr weight-bearing/muscle-strengthening exercise
- Fall prevention
- Tobacco cessation
- Tx ETOH abuse
52
Calcium requirements for women and men
- Women <50: 1,000mg/day
- Men <70: 50-70mg/day
- Women 51+/Men 71+: 1,200mg/day
53
Vitamin D requirements
800-1,000 IU/day
54
Foods high in dairy
- Calcium
- Dark, leafy greens
- Canned sardines and salmon
- Fortified foods
55
Foods high in vitamin D
- Dairy (if fortified)
- Salt-water fish: salmon, mackerel, tuna, sardines
- Liver
- Fortified foods
56
What is diagnosable vitamin D deficiency & what is the vitamin D goal?
- Deficiency: <20ng/mL
| - Goal: >30ng/mL
57
Treatment for vitamin D deficiency
- 50,000 IU D2 or D3 PO weekly (or 6,000 IU daily) for 8-12 weeks
- 1,500-2,000 IU/day maintenance
58
How do you address fall risk in patients at risk for osteoporotic fx?
- Correct vision, home eval for environmental risks
| - Referral for PT/OT for assistive devices (walkers/canes) and balance training/muscle strengthening
59
What are the goals of osteoporosis tx?
- Prevent fx by maintaining bone strength & reducing falls/trauma to bones
- Stable/increase bone mass
- Promote wellness
- Avoid disability
- Reduce suffering
- Tolerability of tx
60
What are some FDA-approved pharmacologic options for osteoporosis?
- Bisphosphonates (alendronate, ibandronate, risedronate, and zoledronic acid), which inhibit osteoclast activity & decrease bone resorption
- Calcitonin - decrease bone resorption
- Estrogen agonist/antagonist (raloxifene)
- Estrogens and/or hormone therapy, tissue-selective estrogen complex (conjugated estrogens/bazedoxifene)
- Parathyroid hormone 1-34 (teriparatide) - daily injections used with PM women with prior fractures
- Denosumab - inhibits RANK ligand (modulator of osetoclast activity)
61
What is the class, MOA, dosing, and side effects of Fosomax (alendronate)?
- Class: bisphosphonate
- MOA: specific inhibitor of osteoclast mediated bone resorption
- Dosing:
Therapeutic=10mg/day or 70mg/wk
Prevention=5mg/day or 35mg/wk
- Alendronate + cholecalciferol (vit D3):
70mg + 2,800 or 5,600 IU vit D once/wk
- Side effects: esophageal sx, MS aches, HA
62
What is the class, MOA, dosing, pt instructions and side effects of Actonel, Atlevia (risedronate)?
- Class: bisphosphonate
- MOA: specific inhibitor of osteoclast mediated bone resorption
- Dosing (therapeutic/prevention):
5mg/day or 35mg/wk or 150mg/mo
- Actonel + calcium: 35mg (4 tabs) + 500mg calcium carbonate (24 tabs)
* Can be taken after breakfast *
- Side effects: esophageal sx, MS aches, HA
63
What is the dosing and pt instructions of Boniva (ibandronate)?
- Daily dose: 2.5 mg
- Monthly dose: 150mg
* Wait 60 min before eating, drinking, or lying down *
64
Instructions and side effects for bisphosphonates
- If PO, must be taken 1st thing in AM w/ 8oz water, wait 30min (alendronate/Fosamax and risendronate/Actonal/Atlevia) to 60 min (ibandronate/Boniva) before eating and be upright 30 min (alend/risend) to 60 min (iband) after taking
- SE: GI & esophageal sx
- Contraindicated w/ GFR <30-35
- Rare reports of osteonecrosis of jaw, femur fx
65
What is the MOA, dosing, pt instructions and side effects of Miacalcin or Fortical (calcitonin)?
- Regulates plasma calcium
- Decreases bone resorption/helps decrease bone pain
- Dose: 200U/spray once in nostril daily
- Miacalcin: 200U/mL 100 units SC or IM every other day
- Adverse rx: rhinitis, GI upset, flushing, rash (inj)
- Not indicated for prophylactic dosing
66
What is the class, MOA, dosing, and side effects of Evista (raloxifene)?
- SERM - Selective Estrogen Receptor Modulator
- May reduce risk of breast cancer
- Less likely than tamoxifen to lead to uterine cancer, hysterectomy, or cataracts
- Therapeutic/prophylactic dose: 60mg/day
- Adverse rxn: hot flashes, increased risk blood clots
67
What is the class, MOA, dosing, pt instructions and side effects of Forteo (teriparatide)?
- Human parathyroid hormone
- Anabolic: increases bone remodeling & increases skeletal mass & bone strength
- Hx osteoporotic fx/multiple risk factors for fx/failed or intolerant to osteoporosis tx
- Dosing: 20mcg SC once daily into thigh/abd wall
- May tx for up to 2 years
- Adverse rxn: dizziness, leg cramps, hypercalcemia, hyperuricemia, inj site rxn
68
What are other options for bisphosphonates?
Boniva (IV):
- Administered every 3mo
- 15sec injection w/ butterfly needle
- Can be obtained at OBGYN/Rheum & Endocrine
Reclast
- Indicated for elderly
- Reduces risk of second fracture
- Given IV 5mg once a month
69
What is Prolia and what does it do?
- RANK ligand inhibitor
| - Inhibits formation, function, & survival of osteoclasts
70
What are some less widely used medications?
- Hormone therapy: NOT typically initiated for sole tx of osteoporosis
* If initiated for perimenopausal sx, does have benefits for bone density*
- Raloxifene/tamoxifen
71
What are some considerations in regards to tx duration?
- Consider benefits
- Consider specific tx
- Evidence of efficacy beyond 5yr limited
- Risk of ONJ & atypical femur fx increases after 5yr w/ bisphosphonates
- If modest, tx 3-5yr
- If still high risk after this duration, consider continuation/change to alternative tx
