BMD Definitions

Diagnostic Category

Diagnostic category is based on the following table endorsed by Osteoporosis Canada. Adapted from the World Health Organization [World Health Organ Tech Rep Ser 1994; 843:1-129] and 2005 International Society for Clinical Densitometry Official Positions [J Clin Densitom 2006; 9(1):22-30].

diagnostic-cat

T-score

Number of standard deviations above (+) or below (-) the mean peak density; Z-score: number of standard deviations above (+) or below (-) the mean density for an individual of that age and sex.
c Fracture Risk (10-year absolute): low (<10%), moderate (10% to 20%), or high (>20%).

Fracture Risk

Fracture risk predicted for an individual by this system applies only for a finite period of time, and that risk will change with advancing age or with the development of new clinical risk factors. Based on 2010 CAROC system. Papaioannou, A et al. 2010 clinical practice guidelines for the diagnosis and management of osteoporosis in Canada: summary. CMAJ 2010;182:1864- 73.

For the purpose of second and subsequent testing (MOHLTC Schedule of Benefits, 2010) “high risk patient” means a patient:

  1. at risk for accelerated bone loss (in the absence of other risk factors, patient age is deemed not to place a patient at high risk for accelerated bone loss); or
  2. with osteopenia or osteoporosis on any previous BMD testing; or
  3. with bone loss in excess of 1% per year as demonstrated by previous BMD testing. High risk patient is limited to a maximum of one test every 12 months unless the ordering physician obtains written prior authorization from a medical consultant. “low risk patient” means a patient who is not a high risk patient. Limited to a maximum of one second test not earlier than 36 months following baseline; subsequent test not earlier than 60 months following the second or any subsequent test.