OSTEOPOROSIS Flashcards
What is the most common metabolic bone disease?
Osteoporosis
When does bone density increase & peak?
Increases dramatically in puberty Peaks in young adults (early 20’s)
What are some determinants to bone density?
Age, race, genetics, timing of puberty (delayed or premature menopause), exercise, calcium intake
Genetics!
When does bone loss begin?
Begins before menses cease; accelerated the first 5-10 years post menopause!!
Ongoing after age 60
Where is most of the bone loss occurring?
Trabecular (cancellous) > cortical (compact) bone
What is causing the increased bone loss?
Increased bone resorption
From sex hormone deficiency = hypogonadism
Hyperparathyroidism = increased PTH
Thyrotoxicosis = Increased bone metabolism
Alcoholism, anorexia, and vitamin D deficiency
What must we ALWAYS ask about in a post-menopausal female when taking a history?
Family history of osteoporosis!
Define osteopenia vs. osteoporosis
Osteopenia = BMD 1-2.5 SD below peak bone density
Osteoporosis = BMD >2.5 SD below peak
How is “peak bone density” determined?
Comparison to bone density of a young healthy adult of same gender and race
In an elderly person, what signs & symptoms might we look for in association with osteoporosis?
Back pain, decrease in height, kyphotic deformity
We must remember that men have osteoporosis too. How does their lifetime risk compare to women’s? How do men with osteoporosis do after a hip fracture?
15-25% vs. 50% in females
They do not do well, 36% of men with hip fractures die the following year
What will you often find on labs for osteoporosis?
NORMAL ionized calcium, PO4
Vitamin D levels low (can be lacking due to diet & sun!)
When indicated test: TSh, cortisol, estradiol, testosterone, PTH
What is our test of choice for osteoporosis?
Bone densitometry: DEXA
What does a DEXA scan look at?
Spinal bone, proximal femur, and other bones (distal radius)
Looks at both trabecular & cortical bone
If a patient has an unexplained hip fracture, or minimal to no trauma, and you get a DEXA scan and she is 1 SD below peak, what does she have?
Severe Osteoporosis!! (not osteopenia, she is automatically put into a higher category)
If a patient has a DEXA scan and the score comes back 2 SD below peak, what treatment would you give her?
Calcium (if she doesn’t meet requirements) Vitamin D (even if levels are normal)
When do we screen for osteoporosis?
Early postmenopause + risk factors
Or >65
What are risk factors for osteoporosis?
Family history, malnourished, alcoholism, renal failure
At what point do you initiate therapy?
Osteoporosis (>2.5 SD below peak)
Presence of “fragility” fracture
Once you start a patient on treatment, can it reverse osteoporosis?
No – can only increase bone density, decrease factures, and halt/slow progression
What are the treatment options for osteoporosis?
Treat underlying etiology; bisphosphonates; SERMS; Calcitonin; Vit D; Calcium; PTH
Can we use estrogen replacement to treat osteoporosis?
CAN ONLY USE WITH HYPOGONADISM OR PREMATURE MENOPAUSE due to adverse side effects
How do bisphosphonates work?
Inhibit osteoclastic bone resorption
How long is the half life of a bisphosphonate?
VERY LONG ~10 years once in the bone
What’s the most common bisphosphonate and how do we instruct our patient to take it?
Alendronate (Fosomax)
Take 30 minutes before breakfast, with 8 oz of water, and remain upright for 30 minutes after
What’s the dosing of Fosomax and the S/E?
70mg weekly
S/E = gastritis & esophagitis
What alternative bisphosphonate offers less GI side effects?
Risedronate (Actonel)
What bisphosphonate can you take monthly?
Ibandronate
What IV bisphosphonate is given every 3 months?
Pamidronate
What IV bisphosphonate is given every 6-12 months?
Zoledronic Acid
With all bisphosphonates, what’s the biggest issue?
Dental concerns!! Dental care is critical!
Who do we treat with bisphosphonates & for how long?
Patients at high risk for fractures NO MORE THAN 5 YEARS
When is a patient with Osteoporosis at risk for a fracture?
Prior fractures; Family History of osteoporosis; low body weight; cigarette consumption; excessive ETOH use; RA; those at risk for falls
What is a SERM medication, who do we use it in?
Selective estrogen receptor modulators – alternative to estrogen!
For post-menopausal women with osteoporosis and those at an increased risk with osteopenia
What medication is our SERMS? What does it prevent? What does it increase?
Raloxifene (Evista)
Doesn’t affect the breasts or uterus. Increases risk of thromboembolism
What medication is inhaled, a by-product of salmon, and increases tensile strength of bone?
Calcitonin
How much does calcitonin increase bone density?
2-3%
What medication helps arrest bone loss the most?
Vitamin D
What’s the recommended daily dose of vitamin D?
400-600 IU/day
What are the recommended daily amounts of Calcium?
1200-1500mg
What 2 patients do we need to be cautious about prescribing calcium to?
Those with thiazide diuretic & glucocorticoids
What injectable medication is given to stimulate osteoblastic activity?
PTH
What are the normal actions of PTH?
Stimulates osteoclasts & osteoblasts
So, how does PTH injection work to just stimulate osteoblasts?
Paradoxical (anabolic) effect when given intermittently (20mcg)
What medication is synthetic form of PTH?
Forteo
Where does Forteo mainly reduce fractures in the body?
Spine
In a patient who has developed a fracture in spite of use of bisphosphonates & calcitonin, what medication could we offer her?
Denosumab
How does Denosumab work?
Monocolonal antibody that decreases bone resorption by inhibiting osteoclasts
Antibody to receptor activator of the nuclear factor-kappa B ligand
What are the best lifestyle modifications for osteoporosis?
Healthy diet, weight bearing exercise!, fall precautions
