Transdiagnostic Therapy for Persistent Physical Symptoms: A mediation analysis of the PRINCE secondary trial

TY - JOUR

T1 - Transdiagnostic Therapy for Persistent Physical Symptoms

T2 - A mediation analysis of the PRINCE secondary trial

AU - James, Kirsty

AU - Patel, Meenal

AU - Goldsmith, Kimberley

AU - Moss-Morris, Rona

AU - Ashworth, Mark

AU - Landau, Sabine

AU - Chalder, Trudie

N1 - Funding Information: The study was funded by Guy's and St. Thomas' Charity. Funding Information: TC, SL, KG and RMM acknowledge that this paper represents independent research part-funded by the National Institute for Health Research (NIHR) Biomedical Research Centre at South London and Maudsley NHS Foundation Trust , King's College London and the NIHR Applied Research Collaboration South London (NIHR ARC South London) at King's College Hospital NHS Foundation Trust . The views expressed 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 The Authors

PY - 2022/12

Y1 - 2022/12

N2 - The PRINCE secondary trial did not find any evidence that transdiagnostic cognitive behavioural therapy (TDT-CBT) plus standard medical care (SMC) was more efficacious than SMC for patients with Persistent Physical Symptoms (PPS) for the primary outcome Work and Social Adjustment Scale (WSAS) at final follow-up (52 weeks). There was a significant treatment effect for TDT-CBT plus CBT compared with SMC for two secondary outcomes: WSAS at the end of active treatment (20 weeks) and symptom severity (Patient Health Questionnaire, PHQ-15) at 52 weeks.To understand mechanisms that lead to effects of TDT-CBT plus SMC versus SMC we performed a planned secondary mediation analysis. We investigated whether TDT-CBT treatment effects on these two secondary outcomes at the end of the treatment could be explained by effects on variables that were targeted by TDT-CBT during the initial phase of treatment. We pre-specified mediator variables measured at mid-treatment (9 weeks).Reductions in catastrophising and symptom focusing were the strongest mediators of TDT-CBT treatment effects on WSAS at the end of treatment. Improvements in symptom focusing also mediated the effect of TDT-CBT on PHQ-15.Future developments of the TDT-CBT intervention could benefit from targeting these mediators.

AB - The PRINCE secondary trial did not find any evidence that transdiagnostic cognitive behavioural therapy (TDT-CBT) plus standard medical care (SMC) was more efficacious than SMC for patients with Persistent Physical Symptoms (PPS) for the primary outcome Work and Social Adjustment Scale (WSAS) at final follow-up (52 weeks). There was a significant treatment effect for TDT-CBT plus CBT compared with SMC for two secondary outcomes: WSAS at the end of active treatment (20 weeks) and symptom severity (Patient Health Questionnaire, PHQ-15) at 52 weeks.To understand mechanisms that lead to effects of TDT-CBT plus SMC versus SMC we performed a planned secondary mediation analysis. We investigated whether TDT-CBT treatment effects on these two secondary outcomes at the end of the treatment could be explained by effects on variables that were targeted by TDT-CBT during the initial phase of treatment. We pre-specified mediator variables measured at mid-treatment (9 weeks).Reductions in catastrophising and symptom focusing were the strongest mediators of TDT-CBT treatment effects on WSAS at the end of treatment. Improvements in symptom focusing also mediated the effect of TDT-CBT on PHQ-15.Future developments of the TDT-CBT intervention could benefit from targeting these mediators.

KW - Persistent physical symptoms

KW - transdiagnostic cognitive behaviour therapy

KW - randomised controlled trial

KW - mediation analysis

UR - http://www.scopus.com/inward/record.url?scp=85141790797&partnerID=8YFLogxK

U2 - 10.1016/j.brat.2022.104224

DO - 10.1016/j.brat.2022.104224

M3 - Article

SN - 0005-7967

VL - 159

JO - Behaviour Research and Therapy

JF - Behaviour Research and Therapy

M1 - 104224

ER -