TY - JOUR
T1 - Six-month outcomes of the CODES randomised controlled trial of cognitive behavioural therapy for dissociative seizures: A secondary analysis
AU - Goldstein, Laura H.
AU - Robinson, Emily J.
AU - Chalder, Trudie
AU - Reuber, Markus
AU - Medford, Nick
AU - Stone, Jon
AU - Carson, Alan
AU - Moore, Michele
AU - Landau, Sabine
N1 - Funding Information:
This paper describes independent research funded by the National Institute for Health Research (Health Technology Assessment programme, 12/26/01, COgnitive behavioural therapy v. standardised medical care for adults with Dissociative non-Epileptic Seizures: A multicentre randomised controlled trial (CODES)). LHG, TC and SL receive salary support from the National Institute for Health Research (NIHR) Maudsley Biomedical Research Centre at the South London and Maudsley NHS Foundation Trust and King's College London. EJR received salary support from the NIHR Biomedical Research Centre based at Guy's and St Thomas’ NHS Foundation Trust and King's College London. JS is supported by an NHS Scotland NHS Research Scotland (NRS) Career Fellowship and JS and AC also acknowledge the financial support of NRS through the Edinburgh Clinical Research Facility. MR benefitted from the support of the NIHR Sheffield Biomedical Research Centre (Translational Neuroscience). The views expressed in this publication are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.
Funding Information:
This paper describes independent research funded by the National Institute for Health Research (Health Technology Assessment programme, 12/26/01, COgnitive behavioural therapy v. standardised medical care for adults with Dissociative non-Epileptic Seizures: A multicentre randomised controlled trial (CODES)). LHG, TC and SL receive salary support from the National Institute for Health Research (NIHR) Maudsley Biomedical Research Centre at the South London and Maudsley NHS Foundation Trust and King's College London. EJR received salary support from the NIHR Biomedical Research Centre based at Guy's and St Thomas? NHS Foundation Trust and King's College London. JS is supported by an NHS Scotland NHS Research Scotland (NRS) Career Fellowship and JS and AC also acknowledge the financial support of NRS through the Edinburgh Clinical Research Facility. MR benefitted from the support of the NIHR Sheffield Biomedical Research Centre (Translational Neuroscience). The views expressed in this publication are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.
Publisher Copyright:
© 2022
PY - 2022/3
Y1 - 2022/3
N2 - PURPOSE: The CODES Trial for adults with dissociative seizures had a predesignated 12-month post-randomisation follow-up point for outcome evaluation. We undertook an exploratory, unplanned, secondary analysis to evaluate the effectiveness of cognitive behavioural therapy plus standardised medical care (CBT+SMC) compared to SMC alone at 6 months post-randomisation, i.e., closer to the end of treatment.METHODS: The analysis of 6-month data followed our previous method of using multiple imputation and an intention-to-treat approach to analyse variables 12 months post-randomisation.RESULTS: The original trial primary outcome of monthly seizure frequency showed greater benefit from CBT+SMC than SMC-alone at 6 months (at p < 0.05). Of 13 comparable previously-defined secondary outcomes, 12 showed a significant between group effect (p < 0.05) in favour of the CBT intervention at 6 months. The average effect size of the comparable previously-defined primary and secondary continuous outcomes was 0.33 at 6 months vs 0.26 at 12 months. The estimated Incidence Rate Ratio (IRR) quantifying monthly seizure reduction was IRR = 0.72 (95%CI from 0.55 to 0.93) at 6 months compared to IRR = 0.78 at 12 months.CONCLUSION: DS-specific CBT (plus SMC) produced evidence of significant benefits at 6 months post- randomisation (around which time CBT was complete) compared to SMC alone; for the majority of these outcomes, better results following CBT (plus SMC) had previously been reported at 12 months. Our pattern of results suggests that short- and longer-term follow-ups are necessary to understand treatment effects in this disorder. Studies only providing short-term follow-up data should be interpreted with caution.
AB - PURPOSE: The CODES Trial for adults with dissociative seizures had a predesignated 12-month post-randomisation follow-up point for outcome evaluation. We undertook an exploratory, unplanned, secondary analysis to evaluate the effectiveness of cognitive behavioural therapy plus standardised medical care (CBT+SMC) compared to SMC alone at 6 months post-randomisation, i.e., closer to the end of treatment.METHODS: The analysis of 6-month data followed our previous method of using multiple imputation and an intention-to-treat approach to analyse variables 12 months post-randomisation.RESULTS: The original trial primary outcome of monthly seizure frequency showed greater benefit from CBT+SMC than SMC-alone at 6 months (at p < 0.05). Of 13 comparable previously-defined secondary outcomes, 12 showed a significant between group effect (p < 0.05) in favour of the CBT intervention at 6 months. The average effect size of the comparable previously-defined primary and secondary continuous outcomes was 0.33 at 6 months vs 0.26 at 12 months. The estimated Incidence Rate Ratio (IRR) quantifying monthly seizure reduction was IRR = 0.72 (95%CI from 0.55 to 0.93) at 6 months compared to IRR = 0.78 at 12 months.CONCLUSION: DS-specific CBT (plus SMC) produced evidence of significant benefits at 6 months post- randomisation (around which time CBT was complete) compared to SMC alone; for the majority of these outcomes, better results following CBT (plus SMC) had previously been reported at 12 months. Our pattern of results suggests that short- and longer-term follow-ups are necessary to understand treatment effects in this disorder. Studies only providing short-term follow-up data should be interpreted with caution.
KW - Cognitive behavioural therapy
KW - Dissociative seizures
KW - Outcomes
KW - Randomised controlled trial
U2 - 10.1016/j.seizure.2022.01.016
DO - 10.1016/j.seizure.2022.01.016
M3 - Article
C2 - 35228117
SN - 1059-1311
VL - 96
SP - 128
EP - 136
JO - Seizure - European Journal of Epilepsy
JF - Seizure - European Journal of Epilepsy
ER -