CALGARY, ALTA. — Two case studies illustrate the benefits of the osteoporosis risk assessment tool known as FRAX.
The brain child of the World Health Organization's Dr. John A. Kanis, FRAX is a computerized assessment tool that combines bone mineral density at the femoral neck with clinical risk factors to help clinicians determine a patient's 10-year risk of osteoporotic fractures.
The National Osteoporosis Foundation's Clinician's Guide to Prevention and Treatment of Osteoporosis (www.nof.org/professionals/Clinicians_Guide.htm
For example, the guidelines recommend that postmenopausal women, and men aged 50 and older, should be treated when they present with:
P A hip or vertebral (clinical or morphometric) fracture.
P Other prior fractures and low bone bass (T score between −1.0 and −2.5 at the femoral neck, total hip, or spine).
P T score of −2.5 or less at the femoral neck, total hip, or spine after appropriate evaluation to exclude secondary causes.
P Low bone bass (T score between −1.0 and −2.5 at the femoral neck, total hip, or spine) and secondary causes associated with high risk of fracture (such as glucocorticoid use or total immobilization).
P A 10-year probability of hip fracture of 3% or greater or a 10-year probability of any major osteoporosis-related fracture of 20% or greater based on the FRAX tool.
Dr. David L. Kendler, who also directs the Osteoporosis Center of British Columbia and is a past president of the International Society for Clinical Densitometry, offered two case examples based on these recommendations. The first is a 54-year-old female smoker with a T score of −2.0. “Her 10-year overall fracture risk would be about 10% and her 10-year hip fracture risk would be about 2.5%, so you would not treat this patient,” he said.
The other example is 81-year-old female with a T score of −1.4. “Her 10-year overall fracture risk is 25% and her 10-year hip fracture risk would be about 3.2%, so you would treat this patient,” said Dr. Kendler, speaking at the annual clinical meeting of the Society of Obstetricians and Gynaecologists of Canada.
FRAX was developed using population-based cohort studies from Europe, North America, Asia, and Australia that represent 249,898 person-years of data. The user is asked to complete fields for age, gender, weight, height, and femoral neck bone mineral density, and to answer yes or no to the following risk factors: previous fracture, parental history of fracture, current tobacco smoker, history of long-term use of glucocorticoids, rheumatoid arthritis, and alcohol intake of three or more units per day.
The user then presses the “calculate” button and the software program provides a 10-year probability of hip fracture and a 10-year probability of a major osteoporotic fracture, defined as one that involves the clinical spine, forearm, hip, or shoulder.
Dr. Kendler, an endocrinologist who is associate professor of medicine at the University of British Columbia, Vancouver, said that the combination of bone mineral density and clinical risk factors “allows us to identify patients at higher risk of osteoporotic fracture. We have moved toward using an intervention threshold based on fracture probability. Treatment will be targeted to patients who will receive the greatest therapeutic benefit.”
According to the International Society for Clinical Densitometry, indications for bone mineral density testing include women age 65 and older; postmenopausal women under age 65 with risk factors; men aged 70 and older; adults with a frailty fracture; adults with a disease or condition associated with low bone mass or bone loss; adults taking medications associated with low bone mass or bone loss; anyone being considered for pharmacologic therapy; anyone being treated for low bone bass, to monitor treatment effect; and anyone not receiving therapy in whom evidence of bone loss would lead to treatment.
Dr. Kendler disclosed receiving grants and/or honoraria from Merck & Co., Eli Lilly & Co., Novartis, Wyeth, Pfizer Inc., Takeda Pharmaceutical Co., and GlaxoSmithKline. The presentation was sponsored by Eli Lilly Canada Inc.
FRAX was developed using population-based cohort studies representing 249,898 person-years of data. DR. KENDLER