Fragility fracture (2023)

This Canadian Task Force on Preventive Health Care (Task Force) guideline provides evidence-based recommendations on screening to prevent fragility fractures in community-dwelling individuals aged 40 and older who are not currently on preventive pharmacotherapy. Fragility fractures result from a minor impact that would not damage normal bone. They occur due to weakened bone structure or low bone mineral density (referred to as osteoporosis).

Current screening practice to prevent fragility fractures often relies solely on bone mineral density (BMD) testing, with the possible addition of risk assessment. Fracture risk assessment tools (e.g., FRAX, CAROC) estimate the percentage risk or risk category for a fracture over five to ten years. BMD testing involves dual energy X-ray absorptiometry of the femoral neck (hip) and provides a T-score (based on standard reference values) that can also be used as an element of risk assessment.

In this guideline, we recommend the "risk assessment-first" screening approach, which involves using a fracture risk estimation tool (e.g., FRAX without BMD), followed by shared decision-making with the patient and BMD testing if the patient is interested in preventive treatment to lower their risk. If BMD is ordered, risk is then re-estimated by adding the BMD T-score to the calculation.

Evidence

Evidence indicates that risk assessment-first screening probably reduces hip fractures and probably slightly reduces clinical fragility fractures (also called major osteoporotic fractures) among females 65 years and older (moderate-certainty evidence). However, for younger females (under 65) and males aged 40 and older, the evidence was indirect or very uncertain and did not establish a benefit.

Acceptability of screening is high, but patients vary in the level of fracture risk at which they choose to initiate treatment. In situations where patient perception of risk and treatment thresholds vary, decision aids could help improve understanding and adherence. Shared decision-making could improve the alignment of screening and treatment with patient preferences.

Harms of screening include overdiagnosis (i.e., individuals correctly classified as high risk (labelled) but who would never have known they were at risk or experienced a fracture, and who are therefore exposed to further assessments or preventive pharmacotherapy without the possibility of benefit) and adverse effects of treatment (e.g., reflux) (low- to moderate-certainty evidence). Rare but serious harms of atypical femoral fracture and osteonecrosis of the jaw may also be increased (low-certainty evidence).

In the judgment of the Task Force, for females aged 65 and older, the reduction in hip and clinical fragility fractures outweighs the potential risk of overdiagnosis (of being labelled "at high risk"), non-serious adverse events, and rare serious adverse events. Risk assessment-first screening was recommended based on the methods used in the randomized controlled trials (RCTs), the accuracy of the Canadian clinical FRAX tool, and reported patient values. Shared decision-making following risk assessment was recommended based on two observations: patient acceptability of treatment differs, and clinical FRAX thresholds for BMD access varied across the RCTs. An interactive decision aid was developed to help patients consider the potential benefits and harms of preventive pharmacotherapy within their individual risk context: frax.canadiantaskforce.ca.

Considering the risk of overdiagnosis (of being labelled high risk) and the small increased risks of treatment-related adverse events, we recommend against screening females aged 40 to 64 and males aged 40 and older. These recommendations are strong because there was no evidence establishing a benefit (evidence on benefits was uncertain or indirect), there was low- to moderate-certainty evidence for harms, and the Task Force places a high value on not expending system-wide resources in this context.

Key Recommendations

We recommend risk assessment-first screening to prevent fragility fractures in females aged 65 and older, as follows (conditional recommendation, low-certainty evidence):

• FRAX: Apply the Canadian clinical FRAX fracture risk assessment tool (without BMD). Use the 10-year absolute risk of major osteoporotic fracture to facilitate shared decision-making about the possible benefits and harms of preventive pharmacotherapy.
• BMD + FRAX: After this discussion, if preventive pharmacotherapy is considered, request BMD measurement using dual energy X-ray absorptiometry of the femoral neck. Then re-estimate fracture risk by adding the BMD T-score to FRAX.

We recommend against screening females aged 40 to 64 and males aged 40 and older to prevent fragility fractures (strong recommendation, very low-certainty evidence).

These recommendations apply to community-dwelling individuals not currently on pharmacotherapy to prevent fragility fractures.

No RCTs on screening intervals or upper age limits were found during our systematic review. Although some observational studies recommend intervals based on age, baseline BMD, or absolute fracture risk, repeating BMD testing every three to eight years did not improve fracture risk prediction. It is unknown how often eligible females should be rescreened; however, rescreening within eight years does not appear useful. Comorbidities and life expectancy should be considered for upper age limits.

The recommendation against screening males and younger females emphasizes the importance of good clinical practice, where clinicians remain alert to changes in physical health and risk factors. Clinicians should also be aware of the importance of secondary prevention and manage patients accordingly.

How does this Task Force guideline differ from other guidelines?

There are similarities but also differences between the Task Force guideline and other recommendations. The Task Force and other guidelines recommend screening females aged 65 and older, but unlike other guidelines, the Task Force recommends risk assessment first, while others recommend BMD testing first, followed by risk assessment. The Task Force recommends risk assessment-first screening for females aged 65 and older, based on the methods used in the randomized controlled trials, the accuracy of the Canadian clinical FRAX tool, and patient values and preferences. Risk assessment-first screening allows for shared decision-making, where patients can consider preventive pharmacotherapy within their individual risk context (before BMD testing). The Task Force has developed a decision aid to support shared decision-making (https://frax.canadiantaskforce.ca/). A risk assessment-first approach to screening females aged 65 and older may also reduce the number of unnecessary BMD tests.

The Task Force recommends against screening females aged 40 to 64 and males aged 40 and older. Other guidelines recommend screening males aged 65 and older, or people aged 50 to 64 with risk factors. However, the Task Force determined that there was no direct evidence establishing a benefit in females aged 40 to 64 or males of any age, and there was low- to moderate-certainty evidence for harms. In addition, screening males is not standard practice in Canada, and participation in screening is low despite the 2010 Osteoporosis Canada recommendations to screen males aged 65 and older.