• Baclofen;
  • chronic pain;
  • morphine;
  • spasticity;
  • ziconotide


To quantify the overall and disaggregated societal costs of intrathecal drug delivery systems (IDDSs) in the treatment of pain and spasticity in the United States.

Materials and Methods

A retrospective review of medical and pharmacy claims was performed on patients with IDDS. Patients were divided into three cohorts according to the conditions that their IDDSs were intended to treat pain, spasticity, or both. Patients also were stratified according to whether or not cost data were available for the implantation of their IDDSs. Total societal costs that were directly attributable to pain or spasticity were summarized, and medical/pharmaceutical encounters were enumerated.


N = 38,951 patients (52.7% women, age 54.1 ± 14.1 years) with IDDSs were identified and included in this study. IDDS patients have an average of 34.0–52.7 (depending on cohort) medical encounters per year, of which an average of 6.3–10.1 is attributable to the condition their IDDS is intended to treat. The average societal cost of the attributable encounters is $12,233 to $20,049 per patient year (inflation-adjusted 2011 U.S. dollars); however, the distribution of these costs is extremely skewed in the positive direction. Inpatient treatment accounts for 65.9% of the societal costs incurred by IDDS patients.


The societal costs for IDDS patients are high and extremely variable. A relatively small number of patients made an extreme number of medical encounters and represent a heavy societal cost burden. In order to reduce the growing societal cost of chronic pain and spasticity treatment, measures should be taken to reduce the resource utilization and costs of the most challenging patients.