Osteoporosis / Calcium Disorders (lectures 1-3) Flashcards
Name the 3 locations you should target in the DXA scan for osteoporosis
Spine, Hip, and femoral head.
T/F - you need a Bone density >2.5 standard deviations below normal in 2 locations to diagnose osteoporosis.
False. It just needs to be in one location.
What are the T scores and Z scores, that are calculated by a DXA scan? Who are they used for, respectively?
T score = compares bone mineral density (BMD) to a normal 30 year old level of the same sex/race.
-Used for older folks (postmenopausal women, as well as men over 50 years old)
Z score = compares BMD to that of an age matched control (Z = exZact same age)
- used for children, premenopausal women, and men under 50
What is a DXA scan?
Dual X ray absorptiometry.
It is similar to xray, checks for bone density.
what does BMD stand for
bone mineral density
What T (or Z) score qualifies for osteopenia? For osteoporosis?
below -1 = osteopenia
below -2.5 = osteoporosis
T or F: Elderly woman trips on her steps, falls down, and breaks her hip. You get labs, which say -2.0 T score for all locations. What is the diagnosis?
Osteoporosis! Although labs are in the range of osteopenia, she has a low trauma fracture, which equals a diagnosis of osteoporosis, no matter the lab values.
Who should be tested for osteoporosis? (give for healthy and those with risk factors)
all women over 65 all men over 70 --- WITH RISK FACTORS -postmenopausal women under 65 -men between 50 and 70
What are the major risk factors for osteoporosis? -6
- prior fragility fracture
- parental history of hip fracture
- glucocorticoid therapy
- excess alcohol intake (>3/day)
- smoking
- rheumatoid arthritis
What are the secondary causes of osteoporosis that you should test for, or gather a history about? hint: there are a shit-ton (13).
- glucocorticoids
- smoking
- alcohol
- hyperparathyroidism (high PTH)
- hypogonadism
- chronic inflammatory diseases (esp. RA)
- hyperthyroidism
- malnutrition
- multiple myeloma
- chronic renal disease
- nutritional deficiencies (calcium/ vitamin D)
- malabsorptive conditions (Celiac or IBD)
- increased kidney excretion of calcium (renal wasting of calcium)
What percentage of patients with hip fractures recover to walk without assistance?
Only 50%!! 25% of hip fracture patients will need a nursing home for the rest of their life.
How do you diagnose osteoporosis?
- DXA scan T/Z score below -2.5
- low trauma fracture.
What are the non-pharmacologic therapies for osteoporosis?
Calcium and Vitamin D.
How does calcium help osteoporosis?
It increases bone density by 1.5%
Vitamin D helps osteoporosis by?
- decreases the risk of falls by 20% (Vitamin D receptors in muscle - better mm contraction/ balance)
- decreases the risk of fractures by 20%
Who should be treated with pharmacologic therapy for osteoporosis?
Anyone with T/Z score below -2.5, or who has a low trauma fracture.
Also, anyone with osteopenia (T score -1 to -2.5) is they have major risk factors for a fracture.
How do you calculate the risk of fracture in someone with osteopenia who you’re not sure if they need meds? What probabilities for general fractures/ hip fractures should be treated?
FRAX calculator.
10 year probabilities
>20% risk of major osteoporotic fracture
>3 % risk of hip fracture
treat for anything above these probabilities!
Who should be given Ca and Vitamin D? (just osteopenics, just osteoporosis, or both.)
Both! these therapies are combined with pharmacologic therapies, but they can be given on their own in someone with osteopenia.
What is the goal level of Vitamin D in someone with osteoporosis? What about a normal person
25OH vitamin D should be above 30 in osteoporotics,
> 20 is fine for a normal person.
What 2 general classes of drugs are there for osteoporosis medications?
- antiresorptives (inhibit osteoclasts)
- anabolics (enhance osteoblast activity)