Changes in illness-related cognitions rather than distress mediate improvements in irritable bowel syndrome (IBS) symptoms and disability following a brief cognitive behavioural therapy intervention.
OBJECTIVE
A previous randomised controlled trial demonstrated that a cognitive behavioural therapy (CBT) self-management intervention significantly improved irritable bowel syndrome (IBS) symptoms and disability compared to treatment as usual (TAU). The current study analysed additional data to establish whether; 1) cognitive, behavioural and emotional factors hypothesized to perpetuate IBS symptoms and disability changed following CBT and, 2) ascertain if changes in these factors over the intervention period mediated treatment effects 6-months later.


METHODS
IBS patients (CBT = 31, TAU = 33) completed measures pre-and-post intervention including: Brief Illness Perception Questionnaire, Hospital Anxiety & Depression Scale and Cognitive and Behavioural Responses to Symptoms Questionnaire. Path models were evaluated to determine whether changes in cognitive and behavioural factors over the treatment period mediated treatment effects.


RESULTS
Compared to TAU, CBT patients showed significant positive changes on several cognitive variables but not anxiety and depression following intervention. Positive change in illness perceptions following intervention mediated the treatment effect on improved IBS symptom severity and social adjustment six months later. Changes in damaging beliefs mediated the effect on social adjustment.


CONCLUSIONS
Change in cognition rather than mood mediated treatment related improvements. Changing negative perceptions of IBS appears to be a particularly important treatment mechanism.
Health Psychology Section, Psychology Department, Institute of Psychiatry, King's College London, UK. Electronic address: joseph.chilcot@kcl.ac.uk.
Joseph
J
Chilcot
Rona
R
Moss-Morris
D000223:Adaptation, Psychological; D000328:Adult; D000339:Affect; D003071:Cognition; D015928:Cognitive Behavioral Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000150:complications / Q000523:psychology* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011614:Psychotherapy, Brief; D012927:Social Control, Informal; D013315:Stress, Psychological / Q000150:complications / Q000523:psychology* / Q000628:therapy
Cognitive behavioural therapy (CBT); Illness perception; Irritable bowel syndrome (IBS); Mediation; Path analysis; Self-Management