Osteoporosis Flashcards
when does risk of glucocorticoid-induced osteoporosis increase significantly?
if taking equivalent of prednisolone 7.5mg a day for 3 or more months
so if pt has to take steroids for at least 3mo, start bone protection immediately (e.g. in PMR)
mx stratification of pt at risk of glucocorticoid-induced osteoporosis?
pt > 65 or those with hx of fragility #: bone protection
pt < 65: bone density scan
- over 0: reassure
- 0 to -1.5: repeat scan in 1-3 years
- less than 1.5: bone protection
what is first-line for bone protect?
alendronate
pt should also be on calcium and vit. d replete
what are the main rfs of osteoporosis
history of glucocorticoid use
history of parental hip fracture
RA
low bmi
smoking
alcohol excess
what are other rfs of osteoporosis
sedentary lifestyle
premature menopause
caucasians, asians
multiple myeloma, lymphoma
CKD
osteogenesis imperfecta, homocystinuria
gi disorders
endocrine disorders
what gi disorders are a/w osteoporosis?
ibd
malabsorption, e.g. coeliac’s
gastrectomy
liver disease
what endo disorders are a/w osteoporosis?
hyperthyroidism
hyperparathyroidism
hypogonadism (e.g. turner’s, testosterone deficiency)
growth hormone deficiency
DM
what medications may worsen osteoporosis
glucocrticoids
SSRIs
antiepileptics
PPIs
glitazones
long-term heparin
aromatase inhibitors e.g. anastrozole
what first-line ix can be done to investigate secondary causes
hx, physical exam
FBC, ESR, CRP, LFTs, serum calcium, albumin, creatinine, phosphate, TFTs
bone profile: densitometry (DEXA)
factors a/w reduced risk of osteoporosis?
high impact exercise
late menopause
Black ethnicity
why does RA increase risk of osteoporosis?
likely multifactorial
increased use of corticosteroids, immobility due to joint pain, effect of systemic inflammation on bone remodelling
when are bisphosphonates CI (renal)?
if eGFR > 35 mL/min/1.73m2
so class 3b, 4 and 5 CKD
when is bone protection indicated in postmenopasual women if the pt is not on steroids?
if >75 -> GIVE
if <75 -> DEXA
T < -2.5 (GIVE alendronate)
when is bone protection indicated in postmenopasual women if the pt is on steroids?
if > 65 -> GIVE (no need for scan)
if < 65 -> DEXA
T < -1.5 (GIVE alendronate)
T > -1.5 (repeat scan 1-3y)
what is incl in 2o prevention of osteoporotic fractures in postmenopausal women?
ALL: vit d + ca unless confident they are replete
SOME: alendronate
what is given if pt cannot tolerate alendronate?
risedronate or etidronate
what is given if pt cannot tolerate bisphosphonates in secondary prevention of osteoporotic fractures?
strontium ranelate and raloxifene (on strict t-scores, e.g. 60y need t score of < 3.5)
what % pt cannot tolerate alendronate and why?
25%
upper gi problems
what drug alternative to alendronate has the strictest criteria?
denosumab
what bisphosphonates are licensed for prevention and treatment of post-menopausal and glucocorticoid-induced osteoporosis?
alendronate
risedronate
etidronate
reduce risk of both vertebral and non-vertebral #
what is ibandronate?
once-monthly oral bisphosphonate
what is raloxifene?
SERM
- shown to prevent bone loss + reduce risk of vertebral #
- increases bone density in spine and prox femur
- may worsen menopausal sx
- increase risk of thromboembolic events
- decreased risk of breast cancer
what is strontium ranelate?
dual action bone agent
- increased deposition of new bone by OB differentiation
- reduced resorption of bone by OC inhibition
poor safety profile - only used last-resort
- CV events
- thromboembolic events
- skin rxr (e.g. stevens-johnson)
when is strontium ranelate CI?
if hx of cvd or significant risk of cvd
what is denosumab?
human mAb against RANK ligand, in turn inhibiting maturation of OC
given as single sc injection 6-monthly
what is teriparatide?
recombinant PTH
good at increasing BMD but unclear role in osteoporosis management
is HRT used in osteoporosis mx?
reduces vertebral and non-vertebral # incidence
BUT concerns for increased rate of CVD and breast cancer, so no longer recommended unless woman suffering from vasomotor symptoms
what are non-medical approaches to osteoporosis mx?
hip protectors - reduce hip # in nursing home pt
compliance is an issue
when should tx be reassessed with ongoing bisphosphonates?
after 5y for oral or 3y for IV zoledronate
should be reassessed with updated FRAX score and DEXA scan
continue indefinitely if high risk
stop if low risk, T score > -2.5, then review in 2 years
who is considered high risk for osteoporosis when considering stopping bisphosphonates?
any of the following are true:
Age >75
Glucocorticoid therapy
Previous hip/vertebral fractures
Further fractures on treatment
High risk on FRAX scoring
T score <-2.5 after treatment
what does a z score adjust for?
age
gender
ethnic factors
what does a t score do?
is bmd compared to a healthy 30 year old
how should oral bisphonates be taken?
swallowed with lots of water while sitting or standing on an EMPTY STOMACH at least 30 MINUTES before breakfast/another oral med
pt should stand or sit upright for at least 30 minutes afte taking
what are CI for oral bisphosphonate therapy?
oesophageal disorders
unsafe swallow
as bisphosphonates can react with oesophageal lining and increase risk of oesophagitis
why should bisphosphonates be taken with water?
minimises risk of oesophageal retention
