Quality of life, resource consumption and costs of spinal cord stimulation versus conventional medical management in neuropathic pain patients with failed back surgery syndrome (PROCESS trial)

BACKGROUND: Chronic back and leg pain conditions result in patients' loss of function, reduced quality of life and increased costs to the society. AIMS: To assess health-related quality of life (HRQoL) and cost implications of spinal cord stimulation plus non-surgical conventional medical management (SCS group) versus non-surgical conventional medical management alone (CMM group) in the management of neuropathic pain in patients with failed back surgery syndrome. METHODS: A total of 100 patients were randomised to either the SCS or CMM group. Healthcare resource consumption data relating to screening, the use of the implantable generator in SCS patients, hospital stay, and drug and non-drug pain-related treatment were collected prospectively. Resource consumption was costed using UK and Canadian 2005-2006 national figures. HRQoL was assessed using the EuroQol-5D (EQ-5D) questionnaire. Costs and outcomes were assessed for each patient over their first 6-months of the trial. RESULTS: The 6-month mean total healthcare cost in the SCS group (CAN$19,486; 12,653 euros) was significantly higher than in the CMM group (CAN$3994; 2594 euros), with a mean adjusted difference of CAN$15,395 (9997 euros) (p<0.001). However, the gain in HRQoL with SCS over the same period of time was markedly greater in the SCS group, with a mean EQ-5D score difference of 0.25 [p<0.001] and 0.21 [p<0.001], respectively at 3- and 6-months after adjusting for baseline variables. CONCLUSIONS: The addition of SCS to CMM in patients with neuropathic leg and back pain results in higher costs to health systems but also generates important improvements in patients' EQ-5D over the same period.