Osteoporosis Flashcards
What is osteoporosis?
disorder affecting the skeletal system characterised by loss of bone mass - defined by WHO as presence of bone mineral density (BMD) of less than 2.5 standard deviations (SD) below the youn adult mean density
Why is detecting osteoporosis important?
increases risk of fragility i.e. non traumatic fractures
certain fragility fractures e.g. fractured neck of femur are associated with significant morbidty and mortality
What is an example of a certain type of fragility fracture that is assoicated with significant morbidity and mortality?
fractured neck of femur
What proportion of post-menopausal women will suffer an osteoporotic fracture?
50%
What are 8 risk factors for osteoporosis?
- Female gender
- Age
- Corticosteroid use
- Smoking
- Alcohol
- Low BMI
- Family history e.g. of parental hip fracture
- Rheumatoid arthritis
What is recommended by guidelines for screening for osteoporosis?
screening tool such as FRAX or QFracture
What information do FRAX or QFracture provide when screening for osteoporosis?
10 year risk of a patient developing a fragility fracture
If a patient has sustained a fragility fracture e.g. Colles’ wrist fracture, what should be done?
assess for osteoporosis
What type of investigation can be used to assess actual bone mineral density?
dual-energy X-ray absorptiometry (DEXA) scan is used
What does a DEXA scan look at?
bone mineral density, looks at hip and lumbar spine
How does the result of the DEXA scan guide treatment?
If either hip or lumbar spine have T score of < -2.5, treatment is recommended
What is the first line treatment for osteoporosis?
oral bisphosphonate such as alendronate
What are the 2 most significant risk factors for osteoporosis?
advancing age and female sex
How does the prevalence of osteoporosis change with age?
increases from 2% at 50 years to more than 25% at 80 years in women
What are 6 risk factors that are used by major risk assessment tools for fragility fractures, such as FRAX?
- History of glucocorticoid use
- Rheumatoid arthritis
- Alcohol excess
- History of parental hip fracture
- Low BMI
- Current smoking
What are 8 weaker risk factors for fragility fractures?
- Sedentary lifestyle
- Premature menopause
- Caucasians and Asians
- Endocrine disorders: hyperthyroidism; hypogonadism e.g. Turner’s, testosterone deficiency; growth hormone deficiency; hyperparathyroidism; diabetes mellitus
- Multiple myeloma, lymphoma
- GI disorders: IBD, malabsorption e.g. Coeliac, gastrectomy, liver disease
- CKD
- Osteogenesis imperfecta, homocytinuria
What are 5 endocrine risk factors for osteoporosis?
- Hyperthyroidism
- Hypogonadism e.g. Turner’s, testosterone deficiency
- Growth hormone deficiency
- Hyperparathyroidism
- Diabetes mellitus
What are 6 medications (other than glucocorticoids) that may worsen osteoporosis?
- SSRIs
- Antiepileptics
- Proton pump inhibitors
- Glitazones
- Long term heparin therapy
- Aromatase inhibitors e.g. anastrozole
What are 4 reasons to perform further investigations if a patient is diagnosed with osteoporosis or has a fragility fracture?
- Exclude diseases that mimic osteoporosis e.g. osteomalacia, myeloma
- Identify cause of osteoporosis and contributory factors
- Assess risk of subsequent fractures
- Select the most appropriate form of treatment
If osteoporosis or fragility fracture are diagnosed, what are 9 further investigations that should be performed?
- History
- Physical examination
- FBC
- Sedimentation rate or CRP
- U+Es
- Bone profile - ALP, calcium, phosphate, albumin, creatinine
- LFTs
- TFTs
- DXA (bone denitometry)
What are 11 possible additional investigations to perform when osteoporosis/ fragility fracture are diagnosed, if indicated?
- Lateral radiographs of lumbar and thoracic spine/ DXA-based vertebral imaging
- Protein immunoelectrophoressi and urinary Bence-Jones proteins (MM)
- 25OHD
- PTH
- Serum testosterone, SHBG, FSH, LH (in men)
- Serum prolactin
- 24 hour urinary cortisol/ dexamethasone suppression test
- Endomysial and/or tissue transflutaminase antibodies (coeliac disease)
- Isotope bone scan
- Markers of bone turnover, when available
- Urinary calcium excretion
Who should be assessed for risk of fragility fracture?
all woman aged ≥65 and all men aged ≥75 should be assessed
younger patients should be assessed in the presence of any of these 8 risk factors:
- previous fragility fracture
- current use of frquent recent use of oral or systemic glucocorticoid
- history of falls
- family history of hip fracture
- other causes of secondary osteoporosis
- low body mass index (BMI) (less than 18.5kg/m²)
- smoking
- alcohol intake of more than 14 units per week
What age group is the FRAX assessment tool valid for?
40-90 years
What patient population group is the FRAX tool based on?
international data - not limited to UK patients
Of FRAX and QFracture, which considers more risk factors?
QFracture - e.g. cardiovascular disease, falls, chronic liver disease, diabetes, tricyclic antidepressants
When is DEXA recommended to be performed to improve the accuracy of FRAX?
if FRAX without BMD shows an intermediate result
What population group is the QFracture tool based upon?
UK primary care dataset
Which age group of patients can QFracture be used for?
30-99 years
What are 2 situations when NICE recommend arranging BMD assessment i.e. DEXA scan rather than using one of the clinical prediction tools?
- Before starting treatment that may have a rapid adverse effect on bone density e.g. sex hormone deprivation for breast or prostate cancer
- People <40* years who have a *major risk factor, such as:
- history of multiple fragility fracture,
- major osteoporotic fracture,
- or current or recent use of high-dose oral or high-dose systemic glucocorticoids
If the FRAX assessment is performed without a bone mineral density, what 3 categories can the result lie within for 10-year risk of fragility fracture? What action should be taken for each?
- Low risk: reassure and give lifestyle advice
- Intermediate risk: offer BMD test
- High risk: offer bone protection treatment
Once the FRAX assessment has been performed with a bone mineral density measure, what 3 groups can the result be categorised into?
- Reassure
- Consider treatment
- Strongly recommend treatment
What result of QFracture will be given when using this to assess fracture risk?
not a category but raw data relating to risk; this can then be interpreted alongside either local or national guidelines, taking into account certain factors such as patient’s age
What are 2 situations when you should recalculate a patient’s fracture risk i.e. repeat FRAX/QFracture?
- If original calculated risk was in the region of the intervention threshold for a proposed treatment and only after a minimum of 2 years
- When there has been a change in the person’s risk factors
When is treatment for osteoporosis indicated? 2 situations
- following osteoporotic fragility fractures in postmenopausal women confirmed to have osteoporosis (T-score or -2.5 SD or below)
- if DEXA scan on screening has identified T score -2.5 or less