IC18: Management of Osteoporosis Flashcards
List at least 4 causes of low bone mass
- Age
- Menopause
- Alcohol consumption
- Smoking
- Physical inactivity
- Low serum calcium
- Medication use
- Secondary due to other disease (eg. drugs, endocrine disorder, GI disease, nutritional disorer, marrow related disorders, organ transplantation)
Menopause: no estrogen, which plays a role in maintaining bone density
State 3 secondary causes of osteoporosis
- Drugs: glucocorticoids, immunosuppresants, Antiseizures (esp phenobarbital & phenytoin), aromatase inhibitors, GnRH agonists & antagonists, heparin, cancer chemotherapy
- Endocrine disorders
- GI disease/nutritional disorders
- Marrow related disorders
- Organ transplantation eg. bone marrow, heart, kidney
Drugs esp glucocorticoids
Why do patients with RA have an increased risk of osteoporosis?
RA patients might be on long term glucocorticoids which predisposes risk for osteoporosis
State the signs & symptoms of osteoporosis
- Asymptomatic (no pain), until patient presents with
- Fragility fracture of spine, hip, wrist, humerus, pelvis (occurs with low trauma)
- hip: height loss & kyphosis
How does a fragility fracture differ from normal fractures?
Fragility: occur due to minimal trauma or no identifiable trauma eg. fall from standing height
Normal: Result from significant trauma
State the group(s) that should be assessed for osteoporosis & fracture risk
- Post menopausal women
- Men >= 65yo
- 1 or 2, with risk factors eg. Family hx of OP/fragility fracture, previous fragility fracture
State the risk factors for osteoporosis or fragility fractures
- FHx of osteoporosis or fragility fracture
- Previous fragility #
- Ageing
- Low body weight
- Height loss > 2cm w/in 3 years
- Early menopause <= 45
- Presence of disease that can lower bone density or increase fracture risk
- Certain medications eg. glucocorticoids
- Low Ca intake (< 500mg/d)
- Excessive alcohol intake (> 2 units/d)
- Smoking (any)
- prolonged immobility
- Hx of falls
State a tool used to detect osteoporosis risk in post-menopausal women
Osteoporosis Self-Assessment Tool for Asians (OSTA)
State the OSTA score breakdowns and the recommendations
- High risk (>20): Consider DXA scan. Chance of finding osteoporosis (low bmd) is high in this group
- Medium risk (0-20): Consider DXA scan if any other risk factor (eg. Fhx etc)
- Low risk (< 0): Consider deferring DXA
Medium/high risk refer to polyclinic for further testing to decide if osteoporosis tx is needed
How is osteoporosis diagnosed?
- Hx of fragility # at vertebral, hip, wrist, humerus, rib or pelvis
* Occurs spontaneously from minor trauma that would not ordinarily result in # (eg. fall from standing height or less)
* Asymptomatic vertebral # can be visually identified as > 20% dec in vetebral height - BMD measurement via DXA hip &/or spine
State the DXA T-score SD breakdowns & their definitions
- T-score ≤ 2.5 SD - osteoporosis
- T-score -1 to 2.5 SD - osteopenia
- T-score ≥ 1SD - normal bone density
In DXA scores,
T-score comapres BMD against ____, while Z-score compares BMD against _____
T-score: against young adult popn
Z-score: against patient’s age & sex
A Z-score of ≤ 2 suggests?
Coexisting problems that can contribute to osteoporosis (eg. glucocorticoid therapy, alcoholism)
State 4 commonly indicated laboratory tests & their rationale to identify secondary contributors of osteoporosis
- Creatinine - determine baseline renal fxn & indicate CKD-MBD
- Full blood count - malignancies, malabsorption, others
- Corrected Calcium
- 25-hydroxyvitaminD
Others - TSH
- Erythrocyte sedimentation rate - indicate rheumatological diseae
- Alkaline phosphatase - incr lvl might indiciate liver disease, paget’s disease
- Serum phosphate
- Spot urine calcium
- Serum total testosterone - decr lvl might indiciate reduce hypogandism
- Corrected Calcium
- incr Ca: primary hyperparathyroidism or malignancy.
- Decr Ca: malabsorption or vit D deficiency
What is FRAX and what is it used for?
FRAX, Fracture Risk Assessment Tool, is a tool to determine absolute fracture risk and assist in treatment decisions.
FRAX indicates the 10 year probability of developing a fracture
Under FRAX, when should osteoporosis treatment be started?
Treatment should be considered if 10-year probability is high for
* 1) Major osteoporotic fracture or
* 2) Hip fracture
To note FRAX uses US cut off, no SG studies yet
State the treatment criteria(s) for osteoporosis
- Patients presenting with fragility #
- Patients without fragility #, but DXA BMD T-score of ≤ 2.5
- Osteopenic (T score > -2.5 but < 1), without a fragility #, but with high # risk (eg. FRAX > 3 %, or ≥ 20% major osteoporotic #)
What is the first-line treatment of osteoporosis?
Oral bisphosphonates (alendronate, risidronate, ibandronate)
Zoledronate is IV
State the pharmacological treatments used to treat osteoporosis
- Bisphosphonates (PO/IV)
- RANKL inhibitor: Denosumab
- Sclerostin inhibitor: Romosuzumab
- Recombinant parathyroid hormone: Teriparatide
- SERM: Raloxifene
State the dosing and frequency of administration of IV Zoledronic acid
5mg q year, as 30min infusion (ensure adequate hydration before infusion)
State the dosing & administration of 1) PO Alendronate
2) PO Risedronate &
3) PO Ibandroante
1) 70mg q week
2) 35mg q week
3) 150mg q month
ibandronate no subsidy & need to fast >6H before taking
List the contraindication(s) of Zoledronic acid
- CrCl < 35ml/min
- Hypocalcemia
List the contraindiaction(s) of PO bisphosphonates (alendronate, risedronate, ibandronate)
- CrCl < 30ml/min
- Hypocalcemia
- Oesophageal or gastric abnormalities (eg. gastric ulcer, achalsia, uncontrolled GERD, erosive esophagitis)
- Inability to stand/sit upright ≥ 30min
- Aspiration risk (eg. difficulty swallowing liquid)
State 2 rare but serious side effects of using IV and PO bisphosphonates
- Osteonecrosis of the jaw
- Atypical femoral # (monitor for thign/hip/groin pain while on tx)
