Construction of a FRAX® model for the assessment of fracture probability in Canada and implications for treatment
- 617 Downloads
We describe the creation of a FRAX® model for the assessment of fracture probability in Canadian men and women, calibrated from national hip fracture and mortality data. This FRAX tool was used to examine possible thresholds for therapeutic intervention in Canada in two large complementary cohorts of women and men.
To evaluate a Canadian World Health Organization (WHO) fracture risk assessment (FRAX®) tool for computing 10-year probabilities of osteoporotic fracture.
Fracture probabilities were computed from national hip fracture data (2005) and death hazards (2004) for Canada. Probabilities took account of age, sex, clinical risk factors (CRFs), and femoral neck bone mineral density (BMD). Treatment implications were studied in two large cohorts of individuals age 50 years and older: the population-based Canadian Multicentre Osteoporosis Study (4,778 women and 1,919 men) and the clinically referred Manitoba BMD Cohort (36,730 women and 2,873 men).
Fracture probabilities increased with age, decreasing femoral neck T-score, and number of CRFs. Among women, 10.1–11.3% would be designated high risk based upon 10-year major osteoporotic fracture probability exceeding 20%. A much larger proportion would be designated high risk based upon 10-year hip fracture probability exceeding 3% (25.7–28.0%) or osteoporotic BMD (27.1–30.9%), and relatively few from prior hip or clinical spine fracture (1.6–4.2%). One or more criteria for intervention were met by 29.2–34.0% of women excluding hip fracture probability (35.3–41.0% including hip fracture probability). Lower intervention rates were seen among CaMos (Canadian Multicentre Osteoporosis Study) men (6.8–12.9%), but in clinically referred men from the Manitoba BMD Cohort, one or more criteria for high risk were seen for 26.4% excluding hip fracture probability (42.4% including hip fracture probability).
The FRAX tool can be used to identify intervention thresholds in Canada. The FRAX model supports a shift from a dual X-ray absorptiometry (DXA)-based intervention strategy, towards a strategy based on fracture probability for a major osteoporotic fracture.
KeywordsBone mineral density Canada Clinical risk factors Fracture FRAX® Osteoporosis
The development of FRAX® was in part supported by a non restricted grant from the International Osteoporosis Foundation and the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis. The hip fracture and mortality statistics were generously provided by the Public Health Agency of Canada using manipulated Canadian Institutes of Health Information data. We thank all those participants in CaMos whose careful responses and attendance made this analysis possible. The authors are indebted to Manitoba Health for the provision of data (HIPC File No. 2007/2008-49). The results and conclusions are those of the authors, and no official endorsement by Manitoba Health is intended or should be inferred. This article has been reviewed and approved by the members of the Manitoba Bone Density Program Committee. The analyses and conclusions in this report reflect the opinions of individual experts and not their affiliated organizations.
Conflicts of interest
William D. Leslie
Speaker fees and unrestricted research grants from Merck Frosst Canada Ltd; unrestricted research grants from Sanofi-Aventis, Procter & Gamble Pharmaceuticals Canada, Inc., Novartis, Amgen Pharmaceuticals Canada, Inc., Innovus 3M, Genzyme Canada; advisory boards for Genzyme Canada, Novartis, and Amgen Pharmaceuticals Canada, Inc.
Lisa M. Lix
Unrestricted research grants from Amgen Pharmaceuticals Canada, Inc. and innovus 3M.
Consultant for Eli Lily, Novartis, Merck, Proctor & Gamble, and Amgen.
David A. Hanley
Consultant and grants from Amgen, Eli Lilly, Merck, Novartis, Proctor & Gamble, Warner-Chilcott, Sanofi-Aventis, Servier, Wyeth-Ayerst, Nycomed.
Jonathan D. Adachi
Consultant/Speaker or research grants from: Amgen, Astra Zeneca, Eli Lilly, GSK, Merck, Novartis, Nycomed, Pfizer, Procter & Gamble, Roche, Sanofi Aventis, Servier, Wyeth, Bristol-Myers Squibb.
Speaker fees and/or unrestricted research grants from Novartis, Amgen, AstraZeneca, Pfizer, Bayer, Procter & Gamble, Lilly, Roche, Servier and Hologic.
John A Kanis
Nothing to declare for FRAX and the context of this paper.
Sources of support
- 28.Richards J, Brown A, Homan C (2001) The data quality study of the Canadian discharge abstract database: a methodological perspective. Proceedings of Statistics Canada Symposium: Achieving data quality in a statistical agency. Statistics Canada, Ottawa Last accessed: June 6, 2009. URL: http://secure.cihi.ca/cihiweb/en/downloads/quality_dadconfpaper_e.pdf
- 29.Canadian Institute for Health Information (2008) Quality Assurance Processes Applied to the Discharge Abstract and Hospital Morbidity Databases. CIHI, Ottawa Last accessed: Aug. 3, 2009. URL: http://secure.cihi.ca/cihiweb/en/downloads/quality_assurance_proc_apr08_e.pdf
- 38.Giangregorio L, Leslie WD (2010) Time since prior fracture is a risk modifier for ten year osteoporotic fractures. J Bone Miner Res (in press)Google Scholar
- 39.Leslie WD, Lix LM, Johansson H, Oden A, McCloskey E, Kanis JA (2010) Independent clinical validation of a Canadian FRAX® Tool: fracture prediction and model calibration. J Bone Miner ResGoogle Scholar
- 40.Kanis JA (2007) WHO Scientific group on the assessment of osteoporosis at primary health care level. Brussels, BelgiumGoogle Scholar
- 52.Fraser LA, Langsetmo L, Berger C et al (2010) Fracture prediction and calibration of a Canadian FRAX® tool: a population-based report from CaMos. Osteoporos Int (in press)Google Scholar
- 53.Leslie WD, Lix LM, Johansson H et al (2010) Independent clinical validation of a Canadian FRAX((R)) tool: Fracture prediction and model calibration. J Bone Miner Res [epub ahead of print]Google Scholar