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

Relations between symptom severity, illness perceptions, visceral sensitivity, coping strategies and well-being in irritable bowel syndrome guided by the common sense model of illness

Irritable Bowel Syndrome (IBS) is a common condition affecting around 10-20% of the population and associated with poorer psychological well-being and quality of life. The aim of the current study was to explore the efficacy of the Common Sense Model (CSM) using Structural Equation Modelling (SEM) in an IBS cohort. One hundred and thirty-one IBS patients (29 males, 102 females, mean age 38 years) participating in the IBSclinic.org.au pre-intervention assessment were included. Measures included IBS severity (Irritable Bowel Syndrome Severity Scoring System), coping patterns (Carver Brief COPE), visceral sensitivity (Visceral Sensitivity Index), illness perceptions (Brief Illness Perceptions Questionnaire), psychological distress (Depression, Anxiety and Stress Scale), and quality of life (IBS Quality of Life scale; IBS-QoL). Using SEM, a final model with an excellent fit was identified (χ² (8) = 11.91, p = .16, χ²/N = 1.49, CFI > .98, TLI > .96, SRMR < .05). Consistent with the CSM, Illness perceptions were significantly and directly influenced by IBS severity (β = .90, p < .001). Illness perceptions in turn directly influenced maladaptive coping (β = .40, p < .001) and visceral sensitivity (β = .70, p < .001). Maladaptive coping and visceral sensitivity were significantly associated with psychological distress (β = .55, p < .001; β = .22, p < .01) and IBS-QoL (β = -.28, p < .001; β = -.62, p < .001). Based on these findings, we argue that to augment the adverse impact of IBS severity on IBS-QoL and psychological distress, psychological interventions will be best to target the mediating psychological processes including illness beliefs, visceral sensitivity and maladaptive coping.

Biopsychosocial Aspects of Functional Gastrointestinal Disorders

In this paper, we provide a general framework for understanding the functional gastrointestinal disorders (FGID) from a biopsychosocial perspective. More specifically, we provide an overview of the recent research on how the complex interactions of environmental, psychological, and biological factors contribute to the development and maintenance of the FGID. We emphasize that considering and addressing all these factors is a conditio sine qua non for appropriate treatment of these conditions. First, we provide an overview of what is currently known about how each of these factors - the environment, including the influence of those in an individual's family, the individual's own psychological states and traits, and the individual's (neuro)physiological make-up - interact to ultimately result in the generation of FGID symptoms. Second, we provide an overview of commonly used assessment tools which can assist clinicians in obtaining a more comprehensive assessment of these factors in their patients. Finally, the broader perspective outlined earlier is applied to provide an overview of centrally acting treatment strategies, both psychological and pharmacological, which have been shown to be efficacious to treat FGID.

Changes in illness perceptions mediated the effect of cognitive behavioural therapy in severe functional somatic syndromes

OBJECTIVE

Although there is substantial evidence that cognitive behavioural therapy alleviates symptoms in functional somatic syndromes, the mechanisms of change are less investigated. This study examined whether changes in illness perceptions mediated the effect of cognitive behavioural therapy.

METHODS

We analysed additional data from a randomised controlled trial comparing completers of cognitive behavioural group therapy (46 patients) to an enhanced usual care group (66 patients). Proposed mediators (illness perceptions) and primary (physical health) and secondary (somatic symptoms and illness worry) outcomes were assessed by means of questionnaires at referral, baseline, end of treatment, and 10 and 16 months after randomisation. Multiple mediation analysis determined whether (1) changes in specific illness perceptions during treatment mediated the effect of cognitive behavioural therapy (primary analysis), and (2) whether changes in illness perceptions during the whole trial period were associated with improved outcome (secondary analysis).

RESULTS

Improvements in illness perceptions during treatment partially mediated the effect of cognitive behavioural therapy on physical health one year after treatment (sum of indirect effects 1.556, BCa 95% CI (0.006; 3.620)). Improving perceived control was particularly important. Changes in illness perceptions from baseline to 16 months after randomisation were associated with clinically meaningful improvements in physical health, somatic symptoms and illness worry during the same period.

CONCLUSION

Our results suggest that changing patients' illness perceptions is an important process in cognitive behavioural therapy for functional somatic syndromes. Challenging patients' own understanding of their illness may hence be a key element of successful treatment.

Irritable bowel syndrome is significantly associated with somatisation in 840 patients, which may drive bloating

BACKGROUND

Psychological factors may influence persistence and perceived severity of symptoms in irritable bowel syndrome (IBS). Literature suggests that somatisation is associated with IBS. However, the relationship between IBS subtype, symptoms of IBS and somatisation is unclear.

AIM

To examine this issue in a large cohort of secondary care patients.

METHODS

Demographic and gastrointestinal (GI) symptom data were collected from 4224 adult patients via the Rome III questionnaire. Somatisation data were collected using the patient health questionnaire-12. Mean somatisation score and number of somatic symptoms were compared between IBS patients and controls with minimal GI symptoms, and between IBS subtypes using analysis of variance. Effect of level of somatisation on symptom frequency was compared according to IBS subtype using a χ(2) test.

RESULTS

840 patients met Rome III criteria for IBS, controls were 2137 patients with GI symptoms without IBS. Mean somatisation scores and number of somatic symptoms were higher in IBS vs. controls (P < 0.001), and in mixed stool pattern IBS (IBS-M), vs. IBS with constipation (IBS-C) or diarrhoea (IBS-D) (P < 0.001). High levels of somatisation were more prevalent in IBS-M (31.7%) vs. IBS-C (22.5%) or IBS-D (20.8%) (P = 0.003). For all IBS subtypes, high levels of somatisation were associated with a greater frequency of bloating or abdominal distension prior to logistic regression.

CONCLUSIONS

IBS is strongly associated with higher levels of somatisation, particularly IBS-M. Bloating may be associated with higher levels of somatisation, perhaps explaining why it can be difficult to treat.

Illness perceptions mediate the relationship between bowel symptom severity and health-related quality of life in IBS patients

PURPOSE

Irritable bowel syndrome (IBS) is a functional bowel disorder with a large negative impact on HRQOL. The present study examines whether severity of bowel symptoms is directly related to HRQOL, and/or indirectly, mediated by the patients' illness perceptions.

METHODS

Patients were recruited from an IBS support group (N = 123), and data were collected online. HRQOL was measured with the Quality of Life Measure for Persons with IBS and illness perceptions with the brief Illness Perception Questionnaire. Mediation models were tested using the bootstrapping procedure developed by Hayes.

RESULTS

Irritable bowel syndrome symptom severity is directly related to total HRQOL and its subscales; after entering the mediator variables (i.e. the patients' illness perceptions) into the model, this direct association remained only significant for total HRQOL. The relationship between bowel symptom severity and total HRQOL was partially mediated by illness perceptions, and its relationship with each of the HRQOL subscales was fully mediated by the patients' illness perceptions. Perceived consequences were a mediator of the relationship between bowel symptom severity, total HRQOL as well as its subscales, with the exception of Sexuality.

CONCLUSIONS

Bowel symptom severity not only has a direct relationship with HRQOL, but also an indirect relationship via the patients' cognitive and emotional representations of their illness. In order to better understand this relationship, future research should not only include illness perceptions but also assess cognitive and behavioural coping responses. Clinicians wanting to improve patients' HRQOL should not only focus on the patients' symptoms, but also on their illness beliefs and coping responses.

Psychological therapies in patients with irritable bowel syndrome: a systematic review and meta-analysis of randomized controlled trials

Background. Irritable bowel syndrome (IBS) is a poorly understood disease with few effective treatments. Psychosocial factors are believed to contribute to the pathogenesis of IBS. Objective. To evaluate the evidence for psychological therapies in IBS treatment. Methods. We searched six medical databases through February 6, 2014, for randomized controlled trials (RCTs) of psychological therapies for the treatment of IBS. Two independent reviewers identified the RCTs, extracted the data, and assessed trial quality. We used the random-effect model to pool standardized mean difference (SMD) and 95% confidence interval (CI) across trials. Results. 15 RCTs that mostly evaluated cognitive behavioral therapy were included. Psychological therapies were associated with improvement in IBS symptoms severity scales (SMD -0.618; 95% CI: -0.853 to -0.383), IBS-Quality of Life (SMD 0.604; 95% CI: 0.440 to 0.768), and abdominal pain (SMD -0.282; 95% CI: -0.562 to -0.001). No statistically significant effect was observed on diarrhea or constipation. Limitations. The trials were at increased risk of bias and the overall sample size was small leading to imprecision. Conclusion. Psychological therapies may improve the quality of life and symptom severity in IBS. The effect size noted is moderate to large and is clinically meaningful.

Psychosocial factors and central sensitivity syndromes

Central sensitivity syndromes (CSSs) represent a heterogeneous group of disorders (e.g., fibromyalgia [FM], irritable bowel syndrome [IBS], chronic headache, temporomandibular disorders [TMDs], pelvic pain syndromes) that share many common symptoms, with persistent pain being the most prominent feature. Although the etiology and pathophysiology of CSSs are currently incompletely understood, central sensitization has emerged as one of the significant mechanisms. Given that there are currently no known cures for CSSs, people living with these disorders must learn to cope with and manage their symptoms throughout their lives. Medical interventions alone have not proven to be sufficient for helping people with CSSs manage their symptoms. A biopsychosocial perspective that considers the ways that biological, psychological, and social factors work independently and jointly to affect a person's experience is the most effective conceptualization and guide for effective treatment. In this article, we discuss several psychological and social features that may influence the experience of a person with CSS and their symptom management, regardless of their specific diagnosis. We highlight the longitudinal aspect of adjustment to illness, the distinction between psychosocial factors as causes of symptoms versus modifiers and perpetuators of symptoms, dispel the notion that all patients with the same diagnosis are a homogeneous group (the "patient-uniformity myth"), and acknowledge the importance of environmental and situational context on symptom management for individuals with any CSS.

A pilot validation of a modified Illness Perceptions Questionnaire designed to predict response to cognitive therapy for psychosis

BACKGROUND AND OBJECTIVES

Clinical responsiveness to cognitive behavioural therapy for psychosis (CBTp) varies. Recent research has demonstrated that illness perceptions predict active engagement in therapy, and, thereby, better outcomes. In this study, we aimed to investigate the psychometric properties of a modification of the Illness Perceptions Questionnaire (M-IPQ) designed to predict response following CBTp.

METHODS

Fifty-six participants with persistent, distressing delusions completed the M-IPQ; forty before a brief CBT intervention targeting persecutory ideation and sixteen before and after a control condition. Additional predictors of outcome (delusional conviction, symptom severity and belief inflexibility) were assessed at baseline. Outcomes were assessed at baseline and at follow-up four to eight weeks later.

RESULTS

The M-IPQ comprised two factors measuring problem duration and therapy-specific perceptions of Cure/Control. Associated subscales, formed by summing the relevant items for each factor, were reliable in their structure. The Cure/Control subscale was also reliable over time; showed convergent validity with other predictors of outcome; predicted therapy outcomes; and differentially predicted treatment effects.

LIMITATIONS

We measured outcome without an associated measure of engagement, in a small sample. Findings are consistent with hypothesis and existing research, but require replication in a larger, purposively recruited sample.

CONCLUSIONS

The Cure/Control subscale of the M-IPQ shows promise as a predictor of response to therapy. Specifically targeting these illness perceptions in the early stages of cognitive behavioural therapy may improve engagement and, consequently, outcomes.

Cognitive-behavioral therapy for irritable bowel syndrome: a meta-analysis

OBJECTIVE

To establish whether cognitive behavioral therapy (CBT) improves the bowel symptoms, quality of life (QOL) and psychological states of irritable bowel syndrome (IBS) patients.

METHODS

Randomized controlled trials (RCTs) of CBT for adult patients with IBS were searched by using PubMed, Scopus and Web of Science. The standardized mean difference (SMD) with 95% confidence intervals (CIs) of the evidence-based outcome measures of the IBS bowel symptoms, QOL and psychological states at post-treatment and follow-up was calculated. Prespecified subgroup analysis was performed.

RESULTS

Eighteen RCTs satisfied our inclusion criteria. In the subgroup analyses, CBT was more effective in reducing IBS bowel symptoms, QOL and psychological states than waiting list controls at the end of the intervention and short-term follow-up. When compared with controls of basic support and medical treatment, the effect sizes were found to favor CBT for the improvement of IBS bowel symptoms at post-treatment and short-term follow-up, but CBT was not superior to controls in improving QOL and psychological states. When comparing CBT with other psychological controls, the effect sizes were almost non-significant.

CONCLUSIONS

For IBS patients, CBT was superior to waiting list, basic support or medical treatment at the end of treatment but not superior to other psychological treatments. The meta-analysis might be limited by the heterogeneities and small sample sizes of the included studies.