diagnosis and risk assessment

Last edited 08/2020 and last reviewed 05/2023

Osteoporosis is often diagnosed clinically following a pathological fracture, usually of the distal radius, spine or hip. These can be:

• low impact fractures – occurs from a fall at or below standing height
• fragility fractures – occurs spontaneously (1)

It is recognised however that intervention is required often before a fracture has occurred.

Bone mineral density (BMD) measurement has been used to predict risk of fracture and diagnose osteoporosis.

• BMD at the femoral neck is used as the reference (1)
• the World Health Organisation define osteoporosis as a bone mineral density of 2.5 standard deviations or more below the young female adult mean (ie a T score < or = to -2.5) (1)
• this definition however encompasses a large proportion of the elderly population and it is therefore not the only consideration in determining treatment.

In addition to bone mineral density, one need to consider the patients's other risk factors which are independent of bone mineral density e.g. - previous fragility fracture, maternal history of hip fracture, risk factors for falling and increased levels of bone resorption markers.

Who to assess risk of fracture (3):

Consider assessment of fracture risk:

• in all women aged 65 years and over and all men aged 75 years and over
  
  
• in women aged under 65 years and men aged under 75 years in the presence of risk factors, for example:
• previous fragility fracture
• current use or frequent recent use of oral or systemic glucocorticoids
• history of falls
• family history of hip fracture
• other causes of secondary osteoporosis
• low body mass index (BMI) (less than 18.5 kg/m2)
• smoking
• alcohol intake of more than 14 units per week for women and more than 21 units per week for men

Do not routinely assess fracture risk in people aged under 50 years unless they have major risk factors (for example, current or frequent recent use of oral or systemic glucocorticoids, causes of possible secondary osteoporososis, untreated premature menopause or previous fragility fracture), because they are unlikely to be at high risk

Notes:

• causes of secondary osteoporosis include
  • endocrine (hypogonadism in either sex including untreated premature menopause and treatment with aromatase inhibitors or androgen deprivation therapy; hyperthyroidism; hyperparathyroidism; hyperprolactinaemia; Cushing's disease; diabetes),
  • gastrointestinal (coeliac disease; inflammatory bowel disease; chronic liver disease; chronic pancreatitis; other causes of malabsorption),
  • rheumatological (rheumatoid arthritis; other inflammatory arthropathies),
  • haematological (multiple myeloma; haemoglobinopathies; systemic mastocytosis),
  • respiratory (cystic fibrosis; chronic obstructive pulmonary disease),
  • metabolic (homocystinuria),
  • chronic renal disease and
  • immobility(due for example to neurological injury or disease)
    
    
    
• when considering assessing risk be aware that risk assessment tools may underestimate fracture risk in certain circumstances, for example if a person:
  • has a history of multiple fractures
  • has had previous vertebral fracture(s)
  • has a high alcohol intake
  • is taking high-dose oral or high-dose systemic glucocorticoids (more than 7.5 mg prednisolone or equivalent per day for 3 months or longer)
  • has other causes of secondary osteoporosis
    
    
    
• fracture risk can be affected by factors that may not be included in the risk tool, for example living in a care home or taking drugs that may impair bone metabolism (such as anti-convulsants, selective serotonin reuptake inhibitors, thiazolidinediones, proton pump inhibitors and antiretroviral drugs
  

Reference:

• (1) Sweet MG et al. Diagnosis and treatment of osteoporosis. Am Fam Physician. 2009;79(3):193-200
• (2) National Osteoporosis Guideline Group (NOGG) 2010. Guidelines for the diagnosis and management of osteporosis in postmenopausal women and men from the age of 50 years in the UK
• (3) NICE (February 2017). Osteoporosis: assessing the risk of fragility fracture