Potential for bone turnover markers to cost-effectively identify and select post-menopausal osteopenic women at high risk of fracture for bisphosphonate therapy.
OBJECTIVE
Over half of all fractures among post-menopausal women occur in those who do not have osteoporosis by bone density criteria. Measurement of bone turnover may cost-effectively identify a subset of women with T-score >-2.5 for whom anti-resorptive drug therapy is cost-effective.


METHODS
Using a Markov model, we estimated the cost per quality adjusted life year (QALY) for five years of oral bisphosphonate compared to no drug therapy for osteopenic post-menopausal women aged 60 to 80 years with a high (top quartile) or low (bottom 3 quartiles) level of a bone turnover marker.


RESULTS
For women with high bone turnover, the cost per QALY gained with alendronate compared to no drug therapy among women aged 70 years with T-scores of -2.0 or -1.5 were $58,000 and $80,000 (U.S. 2004 dollars), respectively. If bisphosphonates therapy also reduced the risk of non-vertebral fractures by 20% among osteopenic women with high bone turnover, then the costs per QALY gained were $34,000 and $50,000 for women age 70 with high bone turnover and T-scores of -2.0 and -1.5, respectively.


CONCLUSIONS
Measurement of bone turnover markers has the potential to identify a subset of post-menopausal women without osteoporosis by bone density criteria for whom bisphosphonate therapy to prevent fracture is cost-effective. The size of that subset highly depends on the assumed efficacy of bisphosphonates for fracture risk reduction among women with both a T-score >-2.5 and high bone turnover and the cost of bisphosphonate treatment.
Schousboe
J T
JT
Division of Health Services Research and Policy, School of Public Health, University of Minnesota, Minneapolis, MN, USA. schouj@parknicollet.com
Bauer
D C
DC
Nyman
J A
JA
Kane
R L
RL
Melton
L J
LJ
Ensrud
K E
KE
D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D019386:Alendronate / Q000008:administration & dosage / Q000191:economics; D015415:Biomarkers / Q000032:analysis; D015519:Bone Density / Q000502:physiology; D050071:Bone Density Conservation Agents / Q000008:administration & dosage* / Q000191:economics; D001851:Bone Diseases, Metabolic / Q000150:complications / Q000188:drug therapy* / Q000191:economics; D001842:Bone and Bones / Q000503:physiopathology*; D003362:Cost-Benefit Analysis / Q000379:methods; D004164:Diphosphonates / Q000008:administration & dosage* / Q000191:economics; D005260:Female; D050723:Fractures, Bone / Q000209:etiology / Q000517:prevention & control*; D006801:Humans; D008390:Markov Chains; D008875:Middle Aged; D017698:Postmenopause / Q000502:physiology; D019057:Quality-Adjusted Life Years; D012307:Risk Factors; D016103:Spinal Fractures / Q000209:etiology / Q000517:prevention & control
D015415:Biomarkers; D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D019386:Alendronate