Fitzy: Osteoporosis Flashcards
What is the definition of osteoporosis?
- 2.5 standard deviations from the mean bone density on DEXA scan
- 1-5 to 2.5 is osteopenia
How T-score is calculated
(Patient’s BMD- young adult mean BMD)/(1 SD of young-adult Mean BMD)
-<2.5 is osteoporosis
What does the drugs’ efficacy for prevention and tx of osteoporosis depend on?
-adequate intake of Vit D and calcium
What are the 2 calcium supplements that a person can take?
- Calcium carbonate
- calcium citrate
Describe calcium carbonate
- 40% calcium, needs acid to dissolve and for absortion
- take “at” or “after” meals
- less stomach acid with aging
describe Calcium citrate
- 20% calcium, no need for stomach acid for absorption
- may be taken between meals
- higher cost
What does 1,25 (OH)3 Vit D promote?
-intestinal Ca2+ absorption
What is the sufficient level of serum Vit D3
30-50
What are the drugs that lower serum Ca2+?
- prednisone, methylprednisolone
- budesonide, inhlaed
- carbamazepine
- phenytoin
- Furosemide
So, if we are going to initiate glucocorticoid therapy, what would we have to do first?
- a Bone densitometry and T-score
- glucocorticoids can impair Vit D absorption and metabolic activation n liver and kidney
What does Vit D make us do?
-absorb Ca2+ in the GI tract
what are the SERMs?
- Raloxifene
- Tamoxifen
What are the Bisphosphonates
- alendronate
- ibandronate
- pamidronate
- resedronate
- zolendronate
Biologicals
- teraparatide
- calcitonin
Antibodies
-denosumab
What cells do osteoclasts come from?
-HSC’s
What cells do osteoblasts come from?
-Mesenchymal stem cells
What drugs inhibit osteoclasts?
- SERMs
- Bisphosphonates
- calcitonin
- Antibodies: denosumab
What causes osteoporosis in older women?
- loss of estrogen during the aging process and at menopause
- E deficit leads to incrased rate ofbone resorption by osteoclasts
What does estrogen normally do?
-it’s usually a restrain on osteoclastic activity