Cost-effectiveness of balloon kyphoplasty and vertebroplasty versus conservative medical management in the USA

Abstract
The cost-effectiveness of surgical versus conservative medical management of vertebral compression fractures in the US was analyzed in the context of inpatient versus outpatient treatment. Surgical intervention (balloon kyphoplasty and vertebroplasty) was found to be cost-effective relative to conservative medical management at a US willingness-to-pay threshold. Introduction To date, only one published study has evaluated the cost-effectiveness (C/E) of balloon kyphoplasty (BKP) or vertebroplasty (VP) in US Medicare patients with osteoporotic vertebral compression fractures. This study further evaluates the C/E of surgical treatment vs. conservative medical management (CMM), expanding on prior modeling by accounting for quality-adjusted life-years gained. Methods A Markov microsimulation model of 1000 patients was constructed. Cost data were based on an analysis of Medicare claims payments, with propensity-score matching performed for BKP and VP vs. controls (CMM). Mortality inputs were based on US life tables, modified to account for age at initial fracture, presence of subsequent fracture(s), and relative risk of mortality by treatment. Separate incremental cost-effectiveness ratios (ICERs) were calculated for BKP and VP in inpatient and outpatient surgical treatment locations to account for individual clinical profiles presenting to each. Results The discounted ICER for inpatient BKP vs. CMM was $43,455 per QALY gained; for outpatient BKP vs. CMM, $10,922; for inpatient VP vs. CMM, $39,774; and for outpatient VP vs. CMM, $12,293. Probabilistic sensitivity analysis confirmed that both BKP and VP would be considered C/E vs. CMM at a US willingness-to-pay (WTP) threshold of $50,000/QALY in 80% and 100% of 500 model simulations, respectively. The most sensitive parameters included quality of life estimates and hazard ratios for mortality. Conclusion While VP and BKP are more expensive treatment options than CMM in the short term, model results suggest interventional treatment is cost-effective, among patients eligible for surgery, at a US WTP threshold. This conclusion supports those from economic analyses conducted in EU-member countries.