Osteoporosis Diagnosis in Canada: FRAX, CAROC, and What to Expect

Getting an osteoporosis diagnosis in Canada involves more than a bone scan. It means understanding your fracture risk, interpreting your DXA results, and working with tools like FRAX and CAROC to decide on next steps. Here's what the process actually looks like.

Who Should Be Screened for Osteoporosis?

Osteoporosis Canada recommends formal bone health assessment based on age and risk factors. The general screening thresholds for DXA scanning covered by provincial health plans are:

• All women 65 and older — automatic eligibility in most provinces
• All men 70 and older — eligible in most provinces
• Postmenopausal women under 65 — if they have major risk factors (prior fracture, family history of hip fracture, low body weight, smoking, alcohol use, secondary causes)
• Men 50–69 — if they have significant risk factors or have had a fragility fracture
• Adults at any age — after a fragility fracture (a fracture from minor trauma like falling from standing height)

Provincial coverage for DXA scans varies. In Ontario, women 65+ and men 65+ with risk factors are covered under OHIP. In British Columbia, women and men 65+ are covered. Alberta covers women 50+ and men 60+ with risk factors. Check with your provincial health authority or family doctor for current eligibility in your province.

The DXA Scan: What It Measures

DXA (Dual-energy X-ray Absorptiometry) is the standard test for measuring bone mineral density (BMD). It uses very low doses of X-ray radiation — less than you'd receive on a transatlantic flight — to measure bone density at two key sites: the lumbar spine (L1-L4) and the femoral neck (hip). These are the most predictive sites for fracture risk.

The scan takes about 15–20 minutes, is painless, and requires no special preparation. You remain clothed but may need to remove metal objects. Results are reported as T-scores and Z-scores.

Understanding Your T-Score

The T-score compares your bone density to a young healthy adult at peak bone mass. This is the primary diagnostic score for osteoporosis in adults over 50:

Understanding Your Z-Score

The Z-score compares your BMD to others of the same age and sex. It's used primarily in younger adults, premenopausal women, and men under 50. A Z-score below -2.0 suggests that your bone loss exceeds what's typical for your age — which often points to secondary causes (medications, medical conditions) worth investigating.

FRAX: The Global Fracture Risk Tool

A T-score alone doesn't tell the whole story. Two people with the same T-score can have very different fracture risks depending on their age, weight, family history, smoking status, and other factors. The FRAX tool (Fracture Risk Assessment Tool), developed by the University of Sheffield and validated for the Canadian population, integrates all of these variables to calculate a 10-year probability of:

• Major osteoporotic fracture (hip, spine, forearm, shoulder)
• Hip fracture specifically

Your doctor can calculate your FRAX score using the online tool at sheffield.ac.uk/FRAX (select Canada as the country). Importantly, FRAX can be calculated with or without a DXA result — making it useful even before a scan. The Canadian version uses Canadian epidemiological fracture data for its calculations.

What FRAX Scores Mean in Canada

Canadian guidelines (from Osteoporosis Canada, updated 2023) use FRAX thresholds to categorize risk and guide treatment decisions:

CAROC: The Canadian-Specific Risk Tool

CAROC (Canadian Association of Radiologists and Osteoporosis Canada) is a simplified risk assessment tool developed specifically for Canadian clinical practice. It uses three inputs to categorize fracture risk into low, moderate, or high:

1. The femoral neck T-score from your DXA scan
2. Your age and sex
3. The presence of major risk factors: prior fragility fracture after age 40, or current systemic glucocorticoid use (prednisone at doses of 7.5 mg/day or equivalent for 3+ months)

CAROC is widely used in Canadian primary care because of its simplicity. It requires only a DXA result (which many patients already have) and two clinical questions. The risk categories align with the same treatment thresholds as FRAX.

What Happens at Your First Osteoporosis Appointment

If your family doctor suspects osteoporosis or identifies you as a candidate for screening, the process typically unfolds as follows:

1. Risk factor review: Your doctor will ask about fracture history, family history (especially parental hip fracture), falls, medications (particularly corticosteroids), medical conditions associated with bone loss, alcohol and tobacco use, and calcium and vitamin D intake.
2. DXA referral: You'll receive a referral for a DXA scan. In most Canadian cities, wait times range from a few weeks to a few months. Private clinics offer faster access in some provinces.
3. Blood tests: To rule out secondary causes of bone loss, your doctor may order bloodwork including complete blood count, calcium, phosphate, creatinine, thyroid function (TSH), 25-hydroxyvitamin D levels, and in some cases protein electrophoresis or parathyroid hormone.
4. Risk calculation: Once DXA results are available, your doctor calculates your CAROC or FRAX risk category.
5. Treatment discussion: Based on your risk category, you'll discuss whether lifestyle changes alone are sufficient, or whether pharmacotherapy (bisphosphonates, denosumab, romosozumab, or others) is appropriate.

Secondary Causes: The Often-Missed Diagnosis

Up to 30% of postmenopausal women and 50% of men with osteoporosis have a secondary cause — an underlying medical condition or medication contributing to bone loss. Common secondary causes in the Canadian population include:

• Vitamin D deficiency (extremely common in Canada given northern latitudes and indoor lifestyles)
• Long-term glucocorticoid (steroid) use — the most common drug-induced cause
• Celiac disease and other malabsorption disorders
• Hyperthyroidism and hyperparathyroidism
• Chronic kidney disease
• Multiple myeloma (particularly important to exclude in men with osteoporosis)
• Excessive alcohol consumption
• Hypogonadism (low testosterone in men, premature menopause in women)

If your Z-score is below -2.0, or if your bone loss seems out of proportion to your risk factors, ask your doctor whether secondary causes have been evaluated.

After the Diagnosis: Monitoring Over Time

Osteoporosis management isn't a one-time event. Serial DXA scans are used to monitor the effectiveness of treatment and the natural progression of bone loss. Canadian guidelines recommend:

• Repeat DXA in 1–2 years after starting pharmacotherapy to assess response
• Once stable, DXA every 2–3 years
• In low-risk patients not on treatment, repeat DXA in 5 years

A decrease in BMD of more than 3–5% at the spine or hip on repeat DXA is considered a significant change and warrants reassessment of treatment compliance, secondary causes, and possibly medication adjustment.