Lecture 6 - Osteoporosis

Question 1

Osteoporosis

Answer 1

decreased mineralization of newly formed osteoid at sites of bone turnover
compromised bone vasculature, leading to osteocytes and bone marrow cell death leading to structural failure and bone fracture
compromised bone density and quality leading to decreased strength and more fractures
lack of both osteoblasts and osteoclasts activity and decreased bone turnover

Question 2

Bone quality refers to?

Answer 2

bone architecture
turnover
mineralization
damage accumulation (i.e. microfractures)

Question 3

Osteomalacia

Answer 3

decreased mineralization of newly formed osteoid at sites of bone turnover

Question 4

osteonecrosis

Answer 4

avascular necrosis
compromised bone vasculature, leading to osteocytes and bone marrow cell death leading to structural failure and bone fracture

Question 5

adynamic bone disease

Answer 5

lack of bone osteoblasts and osteoclasts activity and decreased bone turnover

Question 6

What causes high bone turnover?

Answer 6

hyperparathyroidism 
hyperthyroidism 
hypogonadism in young men and women 
malnutrition 
cyclosporine (?)

Question 7

Male osteoporosis

Answer 7

occurs later than in women

associated with higher mortality than in women

Question 8

What are risk factors for osteoporosis?

Answer 8

female 
asian or caucasian 
low body weight 
tabacco 
excessive EtOH
parents with hip fxs
high bone turnover
medications: (steroids, AI, progesterone, SSRIs) 
Poor vision 
chronic inflammation

Question 9

DXA

Answer 9

Dual Xray Absorpitometry

Question 10

T score

Answer 10

compares pts BMD (bone mass density?) to that of a 30 year old woman - the age of peak bone mass

used for diagnosis of osteoporosis after menopause (use Z score in children and young adults_

Question 11

Z score

Answer 11

compares pts BMD to that of other women her age

Question 12

What T score is considered osteoporosis according to WHO?

Answer 12

based on BMD measurement by central DXA

T-score = -2.5

Question 13

Non-pharmacologic therapies for osteoporosis?

Answer 13

exercise 
fall prevention
calcium 
vitamin D 
avoid tobacco
limit EtOH

Question 14

Who needs pharmacologic treatment for osteoporosis?

Answer 14

history of prior vertebral or hip fracture
T-score = -2.5 after secondary causes ruled out
T-score -1.0 to -2.5 high FRAX score /10yr risk for hip fx >3% and >20% for any major osteoporotic fracture

Question 15

Z-scores < -2.0 suggest ….

Answer 15

secondary cause of osteoporosis and additional evaluation is recommended

Question 16

FRAX

Answer 16

fracture risk assessment tool

Question 17

How do bisphosphonates work in regards to osteoporosis?

Answer 17

inhibit bone resorption

do NOT use in pts with Class3B or higher CKD

Question 18

What are some risks of prolonged bisphosphonate use?

Answer 18

adynamic bone disease

atypical long bone fractures

Question 19

rh-PTH

Answer 19

recombinant human parathyroid hormone

Question 20

Teriparatide

Answer 20

rh-PTH

the only anabolic agent –increases bone formation by osteolasts

FDA approved for use in PMO, men and women, and GIOP

inject 20mcg subq daily

Question 21

When is teriparatide contraindicated?

Answer 21

paget's dz
unexplained alk phos elevation 
child and teens with open epiphyses 
pts with prior radiation therapy 
thyperparathyroidism 
h/o hypercalcemia

Question 22

What are the side effects of teriparatide?

Answer 22

nausea
hypercalciuria
hypercalcemia
leg cramps 
dizziness
orthostatic hypotension 
hyperuricemia 

limit use to 2 years

Question 23

Abaloparatide

Answer 23

analog of human parathyroid hormone related peptide (PTHrP)

stimulation of osteoblast function and increased bone mass

avoid use in: 
paget disease 
bone metastases
skeletal malignancies 
unexplained elevation of alkaline phos
radiation therapy 
open epiphyses

Question 24

Denosumab

Answer 24

humanized mAb against RANKL
increased risk of infections and concerns about neoplasms
concern for increased mortality in pts with multiple myeloma
can be prescribed in pts with CKD but can cause hypocalcemia

SE: rash, peripheral edema, infection, HA, ONJ, hypocalcemia, hypophophatemia

Question 25

How often do you repeat DEXA scan?

Answer 25

1 - 2 years

Question 26

a 57 year old women with hx of Dm, HTN, hypothyroidism and CKD, who smokes and drinks daily
No hx of fxs but her mother had hip fx in her 80s
Her DXA scan (bone densitometry) shows T score -2.6 at the lumbar spine and a T score of -2.0 at the femoral neck
Normal TSH, calcium, vitamin D are normal.
In addition to calcium and vitamin D supplementation, how should you treat this patient?

Answer 26

Denosumab