Abstract ID: A32
Abstract Title: Cost Utility Analysis of Lidocaine Infusions in Fibromyalgia
Authors: Hutcheson MD K1, Simpson Dr.P.H. K2
Medical University of South Carolina Charleston SC USA1, Medical University of South Carolina Charleston SC USA2
Poster Type: Discussion
ABSTRACT BODY
Cost Utility Analysis of Lidocaine Infusions in Fibromyalgia
Kelby Hutcheson, MD; Kit Simpson, DrPH.
Medical University of South Carolina, Charleston, SC USA
Introduction:
The large financial burden combined with limited effective therapeutic options create a double-edged sword when treating fibromyalgia. Treatments are needed that are both cost effective and provide adequate pain relief. Cost utility analysis (CUA) studies investigate the total cost of delivering a treatment compared to overall impact on the patients disease, symptoms and quality of life. The results balance therapeutic benefit with healthcare costs by demonstrating how much it costs to save one quality-adjusted life year for a given treatment.
While the use of intravenous lidocaine for the treatment of pain in fibromyalgia is supported by results from 2 clinical trials and 2 case series, there is no data to indicate whether this treatment is cost effective. We performed a cost-utility analysis comparing usual care with intravenous lidocaine treatment of fibromyalgia pain.
Methods:
A decision tree was constructed in Excel which integrated the best published estimates of direct and indirect costs of fibromyalgia, treatment costs for lidocaine infusions, and quality-adjusted life year (QALY) measures of each treatment approach. The model captures the effects of differences in the proportion of patients with poor scores for pain, mood, and functional ability by estimating a utility weight between 0 and 1 for each patient by the method described by Dolan. The model compares expected values for each treatment for a population of 100 fibromyalgia patients over 5 years and reports differences in utilty gain, total QALYs, and costs.
Results:
The model estimates an average utility improvement from .36 for patients under usual care to .49 under lidocaine treatment at a cost of $10,547 per QALY gained. This advantage of lidocaine therapy is robust to all reasonable variations of key cost and probability parameters.
Discussion:
Results indicate that intravenous lidocaine infusions gives good value for the money for treatment of pain in fibromyalgia. The cost effectiveness ration of $10,547 per QALY falls well below the generally accepted US threshold value of $50,000. The limitations of the model include reliance on the validity of the published data, and the adequacy of the simplification of complex pain states necessary to capture outcomes in the model. Corroboration with clinical trial results is needed for further validation.
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ATTACHED FILES
Reg Anesth Pain Med 2005; 30(3):A32