Increased pain catastrophizing associated with lower pain relief during spinal cord stimulation: results from a large post-market study.

Abstract

Pain catastrophizing is a negative cognitive distortion to actual or anticipated pain. Our aim was to determine if greater catastrophizing has a deleterious relationship with pain intensity and efficacy outcomes in patients receiving SCS. As part of an ongoing Institutional Review Board-approved, multi-site, single arm post-market study, 386 patients were implanted with an Eon Mini™ SCS system and had follow-up visits at 3, 6, and 12 months post-implant. Outcomes collected during the study included, but were not limited to pain intensity using the numeric rating scale (NRS), patient reported pain relief (PRP), satisfaction with their SCS system, quality of life (QOL), pain catastrophizing scale (PCS) and state-trait anxiety index (STAI). NRS scores were associated with higher PCS scores at six months (r = 0.50, p < 0.001). The PCS was a strong predictor of the NRS when controlled for known confounders. Patients with PCS ≥30 at 6-months post-implant had a lower six-month PRP (p < 0.001) and were five times more likely to report dissatisfaction with their SCS device (p < 0.001, OR = 5.46, 95% CI: 2.51-6.35). Additionally, at six months, those who were clinically catastrophizing were three times more likely to report deterioration in QOL (p < 0.002, OR = 3.12, 95% CI: 1.62-5.51). These findings were similar at the 12 months follow visit. Our results indicate that patients with greater catastrophizing, post-implant, were more likely to report higher pain intensity and lower pain relief, quality of life and satisfaction with SCS. These results indicate that associations between pain intensity and pain-related mental health may contribute to influence the overall efficacy of SCS.