98 - Cost-Effectiveness of a novel, non-invasive diagnostic test for chronic low back pain patients

Introduction: Thirty-one million Americans suffer from low back pain. In approximately 20%, the pain is chronic with about 5% ultimately receiving surgery. However, there is no consensus method to differentiate those who will benefit from surgery from those who won’t. Typically, the decision for surgery is made by clinical exam plus MRI imaging, alone or with a provocative discogram (PD). However, PD is controversial for its potential adverse events, subjective nature, and discomfort for the patient. A promising non-invasive diagnostic method for identifying painful lumbar discs in those with discogenic back pain is magnetic resonance spectroscopy (MRS) plus a Nociscan diagnostic algorithm that converts the quantitative and continuous spectral data into a binary pain classification validated against PD.

Objective: The objective of this study was to determine if the Nociscan diagnostic is cost-effective compared with PD.

Methods: We used a decision tree methodology to model the diagnostic accuracy of Nociscan compared to PD, with accuracy being defined by surgical success (15-pt ODI change) after surgery performed at levels meeting painful criteria by MRS or PD. We utilized surgical outcomes data from 325 patients included in a trial comparison of Nociscan and PD (MRS/PD positive probability group) (Gornet, 2019). The PD negative probability group was based on published literature. The model included: Nociscan/PD matches and misses; test sensitivity and specificity; number of levels included in the surgery; PD and surgical adverse event rates; and ODI change from baseline indicating success or failure at 12 months. PD and Nociscan positive and negative rates were assumed the same between groups, but were varied in the sensitivity analysis. Cost included MRI, PD, Nociscan, surgery (fusion or TDR), complications and post-surgical failure, which were quantified using national Medicare rates for physician visits by CPT and hospitalization by ICD-10s, AWP for drug costs, and Medicare fee schedule for laboratory costs. Oneway Sensitivity analyses varied Nociscan and PD +/- rates, adverse event rates, and surgical success rates, while probabilistic sensitivity analysis demonstrated parameter uncertainty across all variables

Results: Total costs for 12-month treatment of those levels diagnosed with PD was $59,710 (SD=$7,490), and with Nociscan was $57,998 (SD=$7,501). Surgical success vs failure rate was 0.78 following Nociscan (SD=0.05) and 0.68 following PD (SD=0.09). Taken together, these cost-effectiveness data indicate that Nociscan is both less costly and more effective when used to select surgical levels in chronic low back pain patients. The Monte Carlo acceptability curve shows that Nociscan is cost-effective over 85% of the time at a $100,000 willingness-to-pay (WTP) level.

Conclusion: Nociscan diagnosis could save $1,712 per surgical procedure while improving overall success by 10% when compared to traditional PD. When extrapolated to the overall population of patients receiving invasive diagnostics for chronic low back pain, Nociscan has the potential to save U.S. healthcare between $144 and $478 million annually. Further analysis is underway to compare PD and Nociscan in a randomized clinical trial.