Osteoporosis Flashcards
What can be defined as a skeletal disorder characterized by a loss of bone osteoid that reduces bone integrity, resulting in an increased risk of fractures?
osteoporosis
In the US osteoporosis causes how many fractures annually?
2 million
White women have a __% lifetime risk of sustaining one or more osteoporotic fractures
40
What are the 5 most common causes of osteoporosis?
- aging
- high-dose corticosteroid administration
- alcoholism
- smoking
- sex hormone deficiency
What is the most common cause of osteoporosis in men?
antiandrogen therapy for prostate conacer
What is caused by a major mutation in the gene coding for type I collagen (bone constitute)?
osteogenesis imperfecta
When does osteoporosis become symptomatic?
following fracture
Are serum calcium, phosphate, and PTH normal, decreased, or increased?
normal
Are vitamin levels D normal, decreased, or increased?
decreased
Serum 25-hydroxyvitamin D levels < __g/mL are considered frank vitamin D deficiency
20
A T-score greater than or equal to __ is considered normal
-1.0
A T-score between __ - __ is considered osteopenia (low bone density)
-1.0 to -2.5
A T-score less than __ is considered osteoporosis
-2.5
Fracture risks increase __-fold for each standard deviation drop in bone mineral density
two
DXA should be obtained every _ years for T scores -1.0 to -1.5
5
DXA should be obtained every _ years for T scores -1.5 to -2.0
3-5
DXA should be obtained every _ years for T scores less than -2.0
1-2
The “_ score” is a statistical term that is used for expressing an individual’s bone density as standard deviation from age-matched, race-matched, and sex-matched means
Z
What are 2 differential diagnoses of osteoporosis?
- osteomalacia
- bone marrow neoplasm
Diet should be high in what 4 things when treating osteoporosis?
- protein
- total calories
- calcium
- vitamin D
What are the 7 specific treatment measures?
1) vitamin D and calcium
2) biphosphonates
3) sex hormones
4) selective estrogen receptor modulators
5) teriparatide
6) calcitonin
7) denosumab
True or False
Sun exposure and vitamin D supplementation are useful in preventing and treating osteoporosis
False
Vitamin D supplementation reduces the incidence of vertebral fractures by __%
37
Calcium supplementation does not reduce the risk of fracture in those with dietary calcium intake over ____ mg daily
1000
Calcium supplementation may be linked to an increase in what?
myocardial infarction
How do biphosphonates help treat osteoporosis?
They increase bone density significantly and reduce the incidence of both vertebral and nonvertebral fractures
Biphosphonates are effective in preventing what?
corticosteroid-induced osteoporosis
To ensure intestinal absorption when should oral bisphosphonates by taken?
in the morning with at least 8 oz of water 40 minutes before consuming anything else
What are 3 oral bisphosphonates?
- alendronate
- risedronate
- ibandronate
What are 2 IV bisphosphonates?
- zoledronic acid
- pamidronate
Bisphosphonate therapy can cause several side effects that are collectively known as what?
the acute-phase response
What are the symptoms of the acute-phase response?
- fever, chills, or flushing
- musculoskeletal pain
- nausea, vomiting, or diarrhea
- fatigue or dyspnea
- edema
- headache or dizziness
- eye inflammation
The acute-phase response typically develops after treatment with what?
their first infusion of zoledronic acid
Bisphosphonate use for more than 5 years is associated with what?
An increased risk in subtrochanteric or femoral shaft fractures
Patients taking oral bisphosphonates have an increased risk of developing what?
esophageal cancer
Bisphosphonates can e discontinued after a _ year course of therapy. Why?
5
Because they have a half life of 10 years in bone
What is essential in preventing osteoporosis in postmenopausal women?
estrogen replacement therapy (ERT)
What can help prevent osteoporosis in hypogonadal men?
testosterone administration
What can be used in place of estrogen for prevention of osteoporosis?
Raloxifene (a selective estrogen receptor modulator)
What is the advantage of taking raloxifene over estrogen supplements?
Reduced risk of breast cancer
However, raloxifene can increase the risk for what?
thromboembolism
Teriparatide is an analog of what hormone?
parathyroid hormone
What does teriparatide do?
It stimulates the production of new collagenous bone matrix that must be mineralized
Teriparatide dramatically increases the bone density in all bones except for which one?
the distal radius
What patients are contraindicated for teriparatide use?
- patients with hypercalcemia **
- those with an increased risk of osteosarcoma (Paget’s disease, open epiphyses, past history)
What should be considered following a course of teriparatide and why?
A course of bisphosphonates in order to retain the improved bone density
Both nasal and parenteral _____ have analgesic effects on bone pain from fractures and have shown to reduce the risk factor of vertebral fractures
calcitonin
______ is a monoclonal antibody that inhibits the proliferation and maturation of preosteoclasts into mature osteoclast bone-resorbing cells
Denosumab
How does denosumab function?
It binds to the osteoclast receptor activator of nuclear factor-kappa B ligand (RANKL)
Denosumab should not used in patients with ___calcemia
hypo
