One year outcomes and costs following a vertebral fracture

Vertebral fractures are believed to be important predictors for future vertebral and other fractures, leading to at least a 4- to 5-fold increase in the risk of subsequent fractures. However, little is known about their associated near-term costs. The purpose of this study was to quantify the subsequent fracture and cost outcomes emanating from patients with an incident vertebral fracture. A probabilistic decision analysis model was developed to estimate the expected cost of all subsequent fractures. We ran Kaplan-Meier time-to-event models on placebo patients in risedronate's pivotal phase III clinical trial data to determine the cumulative incidence or probabilities of all fractures within one year of an incident vertebral fracture. Unit costs for health care payers in the USA and Sweden for vertebral, hip, other, and forearm/wrist fractures were multiplied by fracture probabilities to generate the expected costs of new fractures within one year of incident vertebral fractures. Our analysis found that that 26.1% of vertebral fracture patients with a mean age of 74 years refractured within 1 year (vertebral 17.4%; hip 3.6%; "other" 3.5%; forearm/wrist 1.6%). The calculated medical costs for those patients who refracture within 1 year was $5906 and 3670 euros for the USA and Sweden, respectively, while the weighted average cost across all patients (refracture and non-fracture) within a year of their incident fracture was $1541 (USA) and 958 euros (Sweden). These results suggest that therapies with proven, rapid efficacy may offer important economic value to healthcare payers, providers and patients.