Osteoporosis Flashcards
What is osteoporosis
- Low bone density + impaired bone structure
- Primarily effects females >50 years old and increasing with age
What is a T-score
- Measured bone mineral density to average peal BMD of health, young adult of same sex and ethnicity
What do the T-scores represent
DEXA will be used to measure BMD
1. Negative at or above -1 = denser bones
2. Normal > or equal to 1
3. Osteopenia = -1 to 2.4
4. Osteoporosis = <-2.5
What is FRAX
Fracture Risk Assessment Tool (FRAX)
1. Estimates osteoporotic fracture risk in the next 10 years
*plus other major bones
What are the medications that can worsen osteoporosis
- Anticonvulsants
- Select antiretroviral therapy
- Canagliflozin *
- Heparin
- Glucocorticoids
- Furosemide
- Lithium
- Depo medroxyprogesterone
- Proton pump inhibitors
- SSRIs
- Excessive thyroid supplementation*
- Thizaolindinediones *
*key offenders
What is the etiology of osteoporosis
- Genetics
- Diet
- Lifestyle
- Hormonal
- Aging
Will cause bone loss, then impaired bone quality and decreased bone density which leads to low trauma fractures
What are osteoblasts and osteoclasts
blasts = bone formation
Clasts = bone resorption
How is OPG (osteoprotegrin) related to osteoporosis
- OPG is stimulated by estrogen and inhibits RANKL
*RANKL is needed for osteoclast maturation - Estrogen is decreased in menopause
*which leads to a decrease of osteoclast formation and osteoporosis
What is WNT and Sclerostin
WNT (lipid modified glycoprotein)
1. Regulates proliferation and differentiation of stem cells
2. WNT is stimulated by PTH which signals to increase osteoblasts and bone build up
Sclerostin
1. Produced in osteocytes to stop bone formation
What is the influence of estrogen on osteoporosis
- Suppresses the proliferation and differentiation of osteoclasts
*will inhibit the breakdown of bone increase OPG - Increase osteoclast apoptosis
- Decrease production of RANKL
What is the influence of testosterone on osteoporosis
- Affects bone resorption
- Increases osteoblast differentiation and proliferation
What effects does estrogen have on osteoblasts and osteoclasts
Blasts
1. Decrease apoptosis
2. Decrease oxidative stress
*will have maintenance of bone formation
Clasts
1. Increase in apoptosis
2. Decrease RANKL
*decrease bone resorption
What is the pathophysiology of osteoporosis
Ages 30-45
1. Men and women lose bone at a similar rate
Post-menopause
1. Bone loss is accelerated due to decrease in estrogen
What happens when calcium levels are not maintained
- When increased calcium absorption / reabsorption is not enough to maintain adequate calcium levels = bone resorption
What is the diagnosis criteria for osteoporosis
- Previous Low trauma fracture
*hip or spine regardless of BMD - T-score at or below -2.5
- T-score between -1 and -2.5 with fragility fracture
- T-score between -1 and -2.5 with high FRAX probability
What is the most appropriate prevention therapy for osteoporosis (Younger, health postmenopausal women)
- Estrogen alone (if no uterus)
*bisphosphonate (used if estrogen is CI)
*Raloxifene (for postemenopausal women with an elevated risk of breast cancer)
What are bisphosphonates used for
- To prevent bone loss
- For women with low BMD scores <-1
- Used for who do not meet criteria for osteoporosis treatment
When are medication recommend to prevent bone loss in postmenopausal women
- Premature menopause
- Low BMD (T-score <1.0)
- Low BMD score and other risk factors for fracture
What is the primary goal of prevention of osteoporosis
- Optimize calcium and vitamin D intake
- Regular exercise
- Ensure proper body weight
When should osteoporosis treatment be considered
Postmenopausal women/men aged 50 or older with
1. Hip or vertebral fracture
2. Central DXA t-score of -2.5 or lower
3. Osteopenia with a 10 year FRAX of 3% or more
4. Osteopenia with a 10 year FRAX of any major osteoporitc related fracture of 20% or more
What are some non pharmacological treatments of osteoporosis
- Adequate calcium and vitamin D
- Reduce alcohol
- Reduce caffeine
- Smoking cessation
- Weight bearing exercise
- Fall prevention
What are the first line agents of osteoporosis treatment
Always take with vitamin D and calcium
Bisphosphonates
1. Alendronate (fosamax)
2. Risedronate (Actonel)
3. Zoledronic acid
Denosumab
What are some alternative therapies for osteoporosis
- Raloxifene
- Ibandronate
- Teriparatide
- Abaloparatide
- Romosozumab
What are the ADRs and drug interactions of calcium supplementation
ADRS
1. Constipation
2. Kidney stones
Drug interactions
1. PPIs may decrease absorption
2. Calcium can decrease absorption of many medications
What is the recommend doses for calcium supplementation
- Should not exceed 500 to 600 mg (BID) of elemental calcium
*total 1,200mg elemental calcium per day (post-menopausal women)
What is the dosing recommendation and drug interactions of vitamin D
Dose = 1,000 units
Drug interactions
1. Can increase absorption of aluminum
What is the MOA of Bisphosphonates (oral)
Inhibits osteoclasts activity and bone resorption
What are the dosing schedule of bisphosphonates (oral)
Dosing varies if prevention, treatment or glucocorticoid induced OP
1. Alendronate (fosamax)
*daily but varies if female is taking estrogen
*combination with cholecalciferol available
2. Risedronate (actonel)
*daily, weekly, monthly
3. Ibandronate (boniva)
*monthly, only decreases vertebral fx
What are the CI OF oral bisphosphonates
- Hypocalacemia
- Inability to stay or sit upright for at least 30 minutes
What are the warnings of oral bisphosphonates
- Jaw osteonecrosis
- Atypical femur fx
- Esophagitis, esophageal ulcers, erosions, perforation
- Hypocalcemia
- Renal impairment
What are the AE of oral bisphosphonates
- Dyspepsia
- Dysphagia
- Heartburn
- N/v
- Hypocalcemia
What is the correlation between oral bisphosphonates and bioavailability
- Not absorbed very well
*should not be administered with other meds - Will have decrease GI SE
How should someone take an oral bisphosphonates
- Take with 6 ounces of plain water
- Wait 30 minutes before eating or drinking anything else
- Patient should remain upright or standing for 30 minutes
*if missed dose can take next day
What are some things to keep in mind with the oral bisphosphonates
- Check calcium and vitamin D prior
- Dental work should be done prior to start
- Caution with sodium restriction
- Delayed release (Risedronate) requires acidic gut for absorption
*do not use W/H2RAs or PPIs
What is the MOA of injectable bisphosphonates
Inhibit osteoclast activity and bone resorption
What is the dosing schedule of Ibandronate and zoledronic acid (Injectable Bisphosphonates)
Ibandronate
1. Treatment = 3mg IV every 3 months
Zoledronic acid
1. Prevention = 5mg IV every 2 years
2. Treatment = 5 mg IV once yearly
3. Glucocorticoid induced osteoporosis = 5 g IV once yearly over >15 mins
What are the CI of injectable bisphosphonates
Hypocalcemia
1. Zoledronic acid = CrCl<35mL/min or acute renal impairment
What are the warnings of injectable bisphosphonates
- Same as oral (no GI problems)
- Renal impairment
- Ibandronate = do not use if CrCL <30 mL/min
- Zoledronic acid = use cation in aspirin sensitive asthma
What are the AE of injectable bisphosphonates
- Same as orals (no esophageal problems)
- Acute phase reactions (flu -like sx)
- Zoledronic acid = edema, hypotension, fatigue, dehydration
*injectables are preferred if esophagitis is present
What is the MOA of denosumab (prolia)
- Monoclonal antibody that binds to RANKLand block interaction with RANK to prevent osteoclasts formation
*Causes decrease in bone resorption and increase in bone mass
What is the dosing and CI of denosumab
Dose = 60 mg SC every 6 months
CI = hypocalcemia, pregnancy
What are the warnings of Denosumab (Prolia)
Warnings
1. Osteonecrosis of the jaw
2. Atypical femur fx
3. Hypocalcemia
4. Infections
What are the AE of Denosumab
- HTN
- Fatigue
- Edema
- Dyspnea
- Headache
- N/V/D
- Decreased PO3
What are some pearls of denosumab
- If discontinued, bone loss can be rapid $$$
What is the MOA of selective estrogen receptor modulators (SERM) Raloxifene
- Decrease bone resorption by activating OPG
*estrogen agonist at bone receptors and antagonist at breast receptors leading to breast cancer preventive properties
What is the dosing and BBW of SERMS Raloxifene
Dosing = 60 mg PO daily
BBW
1. Increased risk of VTE
2. Increased risk of death due to stroke
What are the CI of SERMS Raloxifene
History or current VTE
Pregnancy
What are the AE of SERMS Raloxifene
- Hot flashes
- Peripheral edema
- Arthralgia
- Leg cramps
- Flu sx
- Blood clots
What are some pearls of SERMS Raloxifene
- Separate from levothyroxine by several hours
- Discontinue 72 hours prior to and during prolonged immobilization
What is the MOA of equine (horse) estrogen SERM combination (Duavee)
Decreases bone resorption
What is the dose and BBW of equine (horse) estrogen / SERM combination (Duavee)
Dosing = prevention in postmenopausal women with uterus, 1 tab 0.45/20 mg PO daily
BBW
1. Endometrial cancer
2. Increase risk of CVT and stroke
3. Dementia
What are the CI of equine (horse) estrogen / SERM combination (Duavee)
- Breast cancer
- Pregnancy
- Undiagnosed uterine bleeding
- MI or stroke
What are the warnings of equine (horse) estrogen / SERM combination (Duavee)
- Increase risk f breast and ovarian cancer
- Increase risk of retinal vascular thrombosis
- Lipid effects
What are the AE of equine (horse) estrogen / SERM combination (Duavee)
- Nausea
- Diarrhea
- Abdominal pain
- Muscle spams
What are some pearls of equine (horse) estrogen / SERM combination (Duavee)
- Lowest effective dose for the sorted duration possible
*not recommended for women >75 years old
*do not use to prevent CVD
What is the MOA of PTH analogs (teriparatide / forteo, abaloparatide / Tymlos)
Stimulates osteoblast activity and increases bone formation
What is the dosing of PTH analogs (teriparatide / forteo, abaloparatide / Tymlos)
Cumulative lifetime duration < 2 years
1. For postemenopausal and glucocorticoid induced = forteo 20mg daily
2. Postemenopausal = tymlos 80 mcg sc daily
*also use anti-resorption agent (bishophasphonnate)
What are the BBW of PTH analogs (teriparatide / forteo, abaloparatide / Tymlos)
- Osteosarcoma (bone cancer)
What are the warnings of PTH analogs (teriparatide / forteo, abaloparatide / Tymlos)
Hypercalcemia
1. Orthostatic hypotension
2. Caution with urinary stones
43. Avoid in bone malignancy
What are the AE of PTH analogs (teriparatide / forteo, abaloparatide / Tymlos)
- Arthralgias
- Leg cramps
- Nausea
- Orthostasis / dizziness
What are the pearls of PTH analogs (teriparatide / forteo, abaloparatide / Tymlos)
Keep refrigerated
Forteo protect from light
What is the MOA of Romosuzumab (evenity)
Inhibits Sclerostin
*protein that blocks bone formation
What is the dosing and BBW of Romosuzumab (evenity)
Dosing = 210 mg sc (two separate injections) once monthly
*duration is limited to 12 months bc OF
BBW
1. Increased risk of MI, stroke, cardiovascular death
What are the CI, AE, and pearls of Romosuzumab (evenity)
CI = Hypocalcemia
AE = arthralgia, headache, injection site reaction
Pearls = keep refrigerated
What is the MOA of calcitonin (miaclacin)
- Inhibits bone resorption by osteoclasts
What is the dousing and warnings of calcitonin (miaclacin)
Dosing
1. One spray in one nostril daily
2. Injection 100 units daily
Warnings
1. Hypocalcemia
2. Increased risk of malignancy w/long term use
3. Hypersensitivity reaction to salmon derived products
What are the AE and pearls of calcitonin (miaclacin)
AE
1. Back pain
2. Myalgia
Pearls
1. Less effective than other options
2. Long-term risk of cancer increases
What are the aniremodeling drug (prevent breakdown /metabolism)
- Bisphosphonates
- Denosumab
- Raloxifene
- calcitonin
What are the osteoanabolcic drugs (promote build up of bones)
- PTH analogs
- Romosuzumab
What are the effects of parathyroid hormone (PTH) on calcium
- When the parathyroid gland detects low calcium
*PTH production increases which causes
*calcium reabsorption from the kidneys
What are the oral bisphosphonates
- Alendronate (Fosamax)
- Risedronate (Actonel)
- Ibandronate (Boniva)
What are the different injectable bisphosphonates
- Ibandronate (Bonvia)
- Zoledronic acid (Reclast)
What is Raloxifene used for?
Prevention and treatment of osteoporosis