Expressing effects of osteoporosis interventions in terms of postponing of fractures

Abstract

Objective. To estimate the effect from an osteoporosis intervention in terms of postponement of hip fractures.

Design. A Markov model using Nordic data on mortality and hip fracture incidence.

Patients. Women aged 50 years and older with increased risk of hip fracture.

Intervention. A hypothetical intervention that reduces the risk of hip fracture by 50%.

Main outcome measures. Postponement of hip fractures – that is increase in expected fracture-free survival from osteoporosis interventions.

Results. A 1-year treatment would on average postpone hip fracture by 12 days if therapy were started at the age of 50 years and 23, 55, 90 or 74 days if the treatment were started at the ages of 60, 70, 80 or 90 years, respectively. For 10 years of treatment, the benefit was 146, 260, 369, 373 and 167 days, respectively. The younger the patient, the lower the risk of fracture and, consequently, the greater the benefit for those few who actually could benefit.

Conclusions. The benefit in terms of average postponement of hip fractures from osteoporosis intervention was, other things being equal, greatest in women aged 70–90 years. Fracture postponement may represent an alternative to risk reductions in expressing the effect of osteoporosis interventions.