Treatment of peripheral neuropathic pain: A simulation model Montserrat Vera-Llonch a , Ellen Dukes b , Thomas E. Delea a , Si-Tien Wang a , Gerry Oster a, * , The Neuropathic Pain Outcomes Modeling Working Group 1 a Policy Analysis Inc. (PAI), Four Davis Court, Brookline, MA 02445, United States b Pfizer Global Pharmaceuticals, New York, NY, United States Received 24 November 2004; accepted 12 May 2005 Available online 23 June 2005 Abstract Objective: To describe the use of a generalizable stochastic-simulation model of the treatment of neuropathic pain associated with peripheral neuropathies. Methods: We developed a model to simulate treatment outcomes in a hypothetical cohort of patients with peripheral neuropathies. Each patient was randomly assigned an average pretreatment daily pain score (on a 0–10 scale), based on an assumed distribution of mean pretreatment pain scores in the cohort. Patients were randomly assigned daily pain scores, based on their pretreatment average and an assumed distribution of daily pain scores around this mean. Treatment outcomes were then simulated using the expected mean change (vs. baseline) in pain scores. Model outcomes include the expected increase in days with no or mild pain (score 63), days with P30% and P50% reductions in pain intensity, and days with 2- and 3-point absolute reductions in pain intensity. To illustrate its use, the model was estimated over a 12-week period using data from a recent clinical trial of a new antiepileptic (pregabalin). Results: Treatment over 12 weeks (84 days) was projected to result in 26 (±0.4) (mean [±SE]) additional (vs. no treatment) days with no or mild pain, 33 (±0.5) days with a P30% reduction in pain intensity, 28 (±0.4) days with P50% reduction in pain intensity, and 34 (±0.5) and 30 (±0.5) days with P2-point and P3-point absolute reductions in pain intensity. Conclusions: When combined with data on health-state utilities and treatment costs, this new analytical tool can provide a founda- tion for formal cost-effectiveness evaluations of interventions for painful peripheral neuropathies. Ó 2005 European Federation of Chapters of the International Association for the Study of Pain. Published by Elsevier Ltd. All rights reserved. Keywords: Pain; Outcomes; Modeling 1. Introduction Neuropathic pain is caused by a lesion of the periph- eral or central nervous system (or both) manifesting with sensory symptoms and signs (Merskey and Bogduk, 1994, Backonja, 2003, Bennet, 2003, Max, 2002). Com- mon causes of peripheral neuropathic pain include dia- betes, herpes zoster, Acquired Immune Deficiency Syndrome (AIDS), injury, and mechanical pressure on the nerve body (e.g., compression and entrapment syn- dromes), among others (Dworkin, 2002, Dworkin et al., 2003). If inadequately treated, chronic neuropathic pain may be accompanied by depression, anxiety, and sleep disturbance (Haythornthwaite and Benrud-Larson, 2000). While precise estimates of the prevalence of 1090-3801/$32 Ó 2005 European Federation of Chapters of the International Association for the Study of Pain. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ejpain.2005.05.005 * Corresponding author. Tel.: +1 617 232 4400; fax: +1 617 232 1155. E-mail address: goster@pai2.com (G. Oster). 1 Charles Argoff, M.D., Ian Gilron, M.D., Michel Lanteri-Minet, M.D., Paolo Marchettini, M.D., David Rowbotham, M.D., Jordi Serra, M.D., Thomas Toelle, M.D., and Robert van Seventer, M.D. www.EuropeanJournalPain.com European Journal of Pain 10 (2006) 279–285