The current study aims to investigate the efficacy of Mindfulness-Based Cognitive Therapy (MBCT) for reducing fatigue in Inflammatory Bowel Disease patients in remission.

Fatigue is highly prevalent in patients with inflammatory bowel disease (IBD, i.e. Crohn's disease and ulcerative colitis), and may negatively impact patients' illness management, treatment adherence, and quality of life. Given this burden, effective treatment for reducing fatigue in IBD patients is warranted. A promising psychological treatment is Mindfulness-Based Cognitive Therapy (MBCT). MBCT is a standardized, highly structured eight-week group program for reducing stress, depression, fatigue and/or pain. Several meta-analyses have demonstrated the effectiveness of MBCT in reducing psychological complaints and improving quality of life. Moreover, in patients with cancer or chronic fatigue syndrome, there is preliminary evidence that MBCT can be effective in reducing fatigue. Given this lack of evidence for the efficacy of MBCT in reducing fatigue in general and the specific and strongly illness-related nature of fatigue in patients with IBD and characteristics of the illness, including its lifelong and relapsing nature, there is a need to verify whether MBCT is effective in reducing fatigue in IBD patients with severe fatigue.

This randomized controlled trial (RCT) aims to investigate the efficacy of Mindfulness-Based Cognitive Therapy (MBCT) in reducing fatigue in severely fatigued IBD patients. Additionally, the effects of MBCT on clinically relevant secondary outcomes will be examined: fatigue interference, mood, IBD-specific quality of life, sleep quality, labor participation. Also patients' satisfaction will be assessed. Moreover, mediators and moderators will be examined to increase the understanding of why and for whom MBCT is particularly effective.

A randomized controlled trial will be performed, including two conditions: MBCT and a waitlist control group (who will receive MBCT after a waiting period of three months). The study sample will consist of 128 adult patients with IBD in remission and experiencing severe fatigue.

Inclusion Criteria:

• Diagnosed with either Crohn's disease or Ulcerative Colitis
• Currently in remission
• No expectation of a surgery in the upcoming three months
• Score on the subscale 'subjective fatigue' of the CIS (8 items) ≥ 35 (i.e. indicating severe fatigue)
• Age ≥ 18 and ≤ 75 years at the time of study entrance
• Being able to attend eight weekly group sessions of 2.5 hours in the hospital
• Being able to read, write, and speak Dutch.
• Written informed consent

Exclusion Criteria:

• Severe cognitive, neurological or psychiatric co-morbidity that could interfere with patients' participation and/or warrant other treatment, including acute suicidal ideations or behavior, diagnosis of schizophrenia or history of psychotic complaints, bipolar disorder, severe personality disorder, or history of clinically significant drug abuse or substance dependence
• Pregnancy
• Anemia (i.e. Hb < 7.4 for women, < 8.1 for men)
• Change in IBD medication (i.e. use of steroids) within 1 month before study entry
• Currently receiving psychological treatment for fatigue or for psychological/psychiatric problems.