20. Cost-effectiveness of operative vs nonoperative treatment of adult symptomatic lumbar scoliosis an intent-to-treat analysis at 5-year follow-up

Abstract

BACKGROUND CONTEXT There continues to be uncertainty in the appropriate treatment approach for adult symptomatic lumbar scoliosis (ASLS). Nonoperative care has not been shown to improve outcomes. Surgical treatment has been shown to improve outcomes, but is costly with high revision rates. PURPOSE To perform an intent-to-treat cost-effectiveness study comparing operative vs nonoperative care for ASLS. STUDY DESIGN/SETTING Secondary analysis using data from the NIH sponsored study on ASLS that included randomized and observational arms. PATIENT SAMPLE Patients with at least five-year follow-up data were included. OUTCOME MEASURES SRS-22R, Oswestry Disability Index, Short Form-12. METHODS Patients with at least five-year follow-up data were included. Data collected every three months included use of nonoperative modalities, medications and employment status. Costs for index and revision surgeries and nonoperative modalities were determined using Medicare allowable rates. Medication costs were determined using the RedBook and indirect costs were calculated based on reported employment status and income. Quality adjusted life years (QALY) were determined using the SF6D. RESULTS There were 81 of 95 cases in the operative (Op) and 81 of 95 in the nonoperative (NonOp) group with complete five-year follow-up data. Not all patients were eligible for five-year follow-up at the time of the analysis. All patients in the Op and 24 (30%) in the NonOp group had surgery by five years. At five years, the cumulative cost for Op was $96,000 with a QALY gain of 2.44 and for NonOp the cumulative cost was $49,546 with a QALY gain of 0.75 with an ICER of $27,480 per QALY gain. CONCLUSIONS In an intent-to treat analysis, neither treatment was dominant, as the greater gains in QALY in the surgery group come at a greater cost. The ICER for operative compared to nonoperative treatment was above the threshold generally considered cost-effective in the first three years of the study but improved over time and was highly cost-effective at four and five years. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.