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Flashcards in Osteoporosis Deck (41)
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1

Osteoporosis screening for all

Women >65
Men >70

2

Patients taking oral steroids: What do we do to screen?

Assess fracture risk with a DEXA scan in men or women aged >50 taking prednisone >5mg/day for 3 months

3

T score ranges (DEXA scan results)

Normal: -1.0 and above
Osteopenia: Between -1 and -2.5
Osteoporosis: Below -2.5

4

FRAX model parameters

-based on BMD at femoral neck & patient risk factors
-Age, gender, hx of fractures, hx of hip fractures, BMI, oral steroid use, smoker, ETOH use > 3/day

5

Who gets pharmacologic treatment for osteoporosis

-T score > -2.5
-Patients with a 10-year risk for hip fracture of >3%, and a 10-year risk of major osteoporotic fracture of >20%
-History of fracture of hip or spine

6

Prevention of Osteoporosis

-Dietary intake of calcium (1000-1200 mg)
-Adequate intake of vitamin D
-Regular weight bearing exercise
-Smoking cessation
-Prevention of falls

7

"Bone Protecting" Meds

-Calcium/Vitamin D
-Estrogen
-SERMs
-Bisphosphonates
-Anti-RANK Ligand antibodies

8

"Bone Building" Meds

-Parathormone (PTH) or parathyroid hormone-related protein (PTHrP) analogs

9

Anti-resorptive AND anabolic agents

Sclerostin inhibitors

10

Calcium pearls

-Incomplete absorption --> Usually need Vit D for complete absorption
-Constipation is common

11

Calcium citrate

-Can be taken with or without food
-causes less Gi intolerance
-Higher absorption rate, especially in patients with higher gastric pH

12

Estrogen +/- progestin pearls

-Women with an intact uterus should take a progestin in addition to estrogen to decrease risk of endometrial cancer
-No longer first line*** due to increased risk of breast CA, VTE, CVA

13

SERMs (Selective Estrogen Receptor Modulator)

-Raloxifene
-Tamoxifene (not FDA approved for osteoporosis)

MOA: SERM with estrogen-like effects on bone and anti-estrogen effects on uterus/breast

14

Raloxifene

-Used for the prevention AND treatment of osteoporosis

15

SERM ADRs

-Hot flashes and leg cramps may occur
-Increase the risk of VTE
-Short term studies have not shown an increased incidence of endometrial hyperplasia of uterine CA

16

Bazedoxifene

SERM with estrogen like effects on bone and antiestrogen effects on uterus

-MOA: Inhibits stimulating effect of conjugated estrogens

17

Bazedoxifene indications/interactions

-Tx of moderate-severe vasomotor symptoms
-PREVENTION of osteoporosis in postmenopausal women with intact uterus

-Estrogens are CYP3A4 substrates

18

Bisphosphonates

-Alendronate*
-Risedronate
-Zoledronic acid* (IV qyear or q2years)

19

Bisphosphonates MOA

-Inhibits enzyme in mevalonate pathway which disrupts protein prenylation
-Promotes apoptosis, leads to reduced bone resorption

20

Bisphosphonates Pk (best absorbed when? Half life?)

-Absorbed best on empty stomach
-Plasma half life = 1 hour, can persist in bone for lifetime

21

Clinical Indications for Bisphosphonates

-Prevention and tx of osteoporosis
-Hypercalcemia associated with malignancy and Paget's

22

Pearls of Bisphosphonates

-Increased BMD leads to decreased vertebral and nonvertebral/hip fx with osteoporosis
-Prevents bone loss in early PMP women
-Prevents bone loss associated with steroid therapy

23

How exactly should a patient take bisphosphonates?

-With 8 ounces of plain water after an overnight fast, remain upright and NPO except water for 30-60min
-Decreases risk of esophagitis
-Take on empty stomach

24

When would IV dosing be beneficial?

-Esophageal abnormalities
-Esophageal intolerance
-Pts who cannot remain upright for 30-60 min
-Pts who forget to take them

25

Bisphosphonates monitoring

-Reeval at 1 month to assess tolerance
-CTX at 3 and 6 months
-DEXA at 1 year, q2year after to check BMD

26

CI with Bisphosphonates

-GFR <35mL/min
-Vit D depletion (25-hydroxy vit D <30 before starting)
-Osteomalacia
-Hypocalcemia
-Impaired swallowing/esophageal disorders
-Pregnancy or lactation

27

Interactions with Bisphosphonates

-No CYP
-Food and multivalent cations (Fe2+/Ca2+ supplements, antacids) can interfere with absorption

28

Bisphosphonates ADRs

-PO: GI symptoms (chemical esophagitis rare with nondaily regimens)
-IV: transient flu-like febrile illness
-IV>PO: ocular effects**, call if decreased vision, eye pain, light sensitivity, or redness
-Osteonecrosis of the jaw** (IV>>>PO): refer to dental BEFORE starting bisphosphonates
-Atypical femur fractures** often report it "doesn't feel right", consider imaging bilaterally

29

Minimizing ADRs of Bisphosphonates

-Use FRAX to decide if they need it
-Stop after 3 (IV) or 5 years (PO) in pts at low risk
-Wait additional 3-5 years before taking holiday if high risk
-Check BMD with DEXA/FRAX +/- turnover markers
-Continue if high risk

30

Anti-RANK Ligand Abs, drug and MOA

Denosumab

MOA: shuts down development of osteoclasts