TY - JOUR
T1 - Examining the Duration of Carryover Effect in Patients With Chronic Pain Treated With Spinal Cord Stimulation (EChO Study)
T2 - An Open, Interventional, Investigator-Initiated, International Multicenter Study
AU - Meier, Kaare
AU - de Vos, Cecile C.
AU - Bordeleau, Martine
AU - van der Tuin, Sharon
AU - Billet, Bart
AU - Ruland, Thomas
AU - Blichfeldt-Eckhardt, Morten Rune
AU - Winkelmüller, Matthias
AU - Gulisano, Helga Angela
AU - Gatzinsky, Kliment
AU - Knudsen, Anne Lene
AU - Hedemann Sørensen, Jens Christian
AU - Milidou, Ioanna
AU - Cottin, Sylvine Carrondo
PY - 2024/7
Y1 - 2024/7
N2 - Objectives: Spinal cord stimulation (SCS) is a surgical treatment for severe, chronic, neuropathic pain. It is based on one to two lead(s) implanted in the epidural space, stimulating the dorsal column. It has long been assumed that when deactivating SCS, there is a variable interval before the patient perceives the return of the pain, a phenomenon often termed echo or carryover effect. Although the carryover effect has been problematized as a source of error in crossover studies, no experimental investigation of the effect has been published. This open, prospective, international multicenter study aimed to systematically document, quantify, and investigate the carryover effect in SCS. Materials and Methods: Eligible patients with a beneficial effect from their SCS treatment were instructed to deactivate their SCS device in a home setting and to reactivate it when their pain returned. The primary outcome was duration of carryover time defined as the time interval from deactivation to reactivation. Central clinical parameters (age, sex, indication for SCS, SCS treatment details, pain score) were registered and correlated with carryover time using nonparametric tests (Mann-Whitney/Kruskal-Wallis) for categorical data and linear regression for continuous data. Results: In total, 158 patients were included in the analyses. A median carryover time of five hours was found (interquartile range 2.5;21 hours). Back pain as primary indication for SCS, high-frequency stimulation, and higher pain score at the time of deactivation were correlated with longer carryover time. Conclusions: This study confirms the existence of the carryover effect and indicates a remarkably high degree of interindividual variation. The results suggest that the magnitude of carryover may be correlated to the nature of the pain condition and possibly stimulation paradigms. Clinical Trial Registration: The Clinicaltrials.gov registration number for the study is NCT03386058.
AB - Objectives: Spinal cord stimulation (SCS) is a surgical treatment for severe, chronic, neuropathic pain. It is based on one to two lead(s) implanted in the epidural space, stimulating the dorsal column. It has long been assumed that when deactivating SCS, there is a variable interval before the patient perceives the return of the pain, a phenomenon often termed echo or carryover effect. Although the carryover effect has been problematized as a source of error in crossover studies, no experimental investigation of the effect has been published. This open, prospective, international multicenter study aimed to systematically document, quantify, and investigate the carryover effect in SCS. Materials and Methods: Eligible patients with a beneficial effect from their SCS treatment were instructed to deactivate their SCS device in a home setting and to reactivate it when their pain returned. The primary outcome was duration of carryover time defined as the time interval from deactivation to reactivation. Central clinical parameters (age, sex, indication for SCS, SCS treatment details, pain score) were registered and correlated with carryover time using nonparametric tests (Mann-Whitney/Kruskal-Wallis) for categorical data and linear regression for continuous data. Results: In total, 158 patients were included in the analyses. A median carryover time of five hours was found (interquartile range 2.5;21 hours). Back pain as primary indication for SCS, high-frequency stimulation, and higher pain score at the time of deactivation were correlated with longer carryover time. Conclusions: This study confirms the existence of the carryover effect and indicates a remarkably high degree of interindividual variation. The results suggest that the magnitude of carryover may be correlated to the nature of the pain condition and possibly stimulation paradigms. Clinical Trial Registration: The Clinicaltrials.gov registration number for the study is NCT03386058.
KW - Carryover
KW - echo effect
KW - neuropathic pain
KW - SCS
KW - spinal cord stimulation
U2 - 10.1016/j.neurom.2024.01.002
DO - 10.1016/j.neurom.2024.01.002
M3 - Journal article
C2 - 38456888
AN - SCOPUS:85187365011
SN - 1094-7159
VL - 27
SP - 887
EP - 898
JO - Neuromodulation
JF - Neuromodulation
IS - 5
ER -