Pain perception in irritable bowel syndrome

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by chronic abdominal discomfort or pain in the absence of detectable organic disease. IBS is common and is associated with a significant impairment in health-related quality of life. Enhanced perception of visceral stimuli ("visceral hypersensitivity") appears to be an important pathophysiological mechanism. Early IBS studies using functional brain imaging techniques suggest an alteration in central pain modulation circuits, rather than an increased sensitivity of peripheral visceral pain pathways. The frequent comorbidity with psychiatric disorders suggests the possibility of shared pathophysiological mechanisms and etiologic factors.     

Cognitive-behavioral treatment of irritable bowel syndrome

There is increasing evidence that supports the view that irritable bowel disorder (IBS) is a disorder of brain-gut function. Cognitive-behavioral therapy (CBT) has received increased attention in light of this recent shift in the conceptualization of IBS. This review has two main aims. The first is to provide a critical review of controlled trials on CBT for IBS. The second is to discuss ways of further developing CBT interventions that are more clinically relevant and meaningful to health care providers and individuals with a diagnosis of IBS. A theme from a CBT intervention will be presented to illustrate how CBT interventions can be incorporated within a larger social context. A review of CBT for IBS lends some limited support for improvement in some IBS symptoms and associated psychosocial distress. This conclusion needs to be expressed with some caution, however, in light of many methodological shortcomings including small sample sizes, inadequate control conditions and failure to identify primary versus secondary outcome measures. In addition, future studies will need to further develop more relevant CBT protocols that more fully integrate the patient's perspective and challenge social cognitions about this stigmatized disorder.     

Brief cognitive-behavioral internet therapy for irritable bowel syndrome

While cognitive-behavioral therapy for IBS is quite effective, the limited availability of competent therapists and lack of access to treatment remain problematic. This paper reports on a small, randomized, controlled trial of a five week internet based cognitive-behavioral intervention for IBS with limited therapist feedback via e-mail. Fifty-four IBS patients were recruited via the internet and randomly assigned to either immediate treatment or a wait-list control group. Thirty-one subjects completed the post-treatment assessment. 77% of treatment completers also completed a 3-month follow-up assessment. Treatment completers experienced statistically and clinically significant declines in IBS symptoms and improvements in quality of life. Those gains were substantially maintained at follow-up. Treatment efficacy was partially mediated by reductions in the tendency to catastrophize the social and occupational implications of symptoms, suggesting that catastrophizing may be an important target for treatment.     

Physiological reactivity to stressors in irritable bowel syndrome patients, inflammatory bowel disease patients and non-patient controls.

Irritable Bowel Syndrome (IBS) patients were compared with Inflammatory Bowel Disease (IBD) patients and non-patient controls on four separate physiological measures (heart rate, finger-tip temperature, skin resistance level, and forehead EMG) for their physical reactivity to 'laboratory stressors'. It was predicted that the IBS patients would respond to these stressors with more physiological reactivity than the two other groups. There were initial basal differences among the groups on heart rate and finger-tip temperature: in general, the IBS patients had lower basal heart rates and the non-patient controls had lower finger-tip temperatures. These findings are contrary to the previous body of literature regarding possible sympathetic nervous system (SNS) arousal states in the IBS patient. The results also indicated IBS patients were not significantly different than the IBD patients or the non-patient controls in their reactivity to stressors. Previous literature has suggested that IBS in their reactivity to stressors. Previous literature has suggested that IBS patients have an enhanced SNS arousal or an SNS mediated reactivity to environmental stressors, our current study has not found these results.     

The role of anxiety and depression in the irritable bowel syndrome

Using a reliable and valid structured diagnostic interview scale (ADIS-R), and patients with careful medical characterization, we found significantly more diagnosable psychopathology, particularly anxiety disorders, among treatment seeking patients with irritable bowel syndrome than among comparable age and sex samples of treatment seeking patients with Inflammatory Bowel Disease. Significant differences were also found on the Hamilton Anxiety Rating Scale and Hamilton Rating Scale for Depression between IBS patients and the IBD patients and controls, who did not differ. Comparable levels of psychiatric disorder among parents of probands were found in all three groups. The results are consistent with Latimer's (1983) notion of IBS patients being a subclass of 'neurotics'.     

Behaviorally treated irritable bowel syndrome patients: a four-year follow-up

Nineteen of 27 patients suffering from Irritable Bowel Syndrome (IBS) who had completed a multicomponent treatment involving progressive muscle relaxation, thermal biofeedback, cognitive therapy and IBS education were located and evaluated 4 yr posttreatment. Seventeen of 19 (89.5, or 63% of the total original sample) rated themselves as more than 50% improved. Six of the 12 patients (50%) who submitted symptom monitoring diaries met our criteria for clinical improvement, i.e. achieving at least a 50% reduction in primary IBS symptom scores. The means on all measures at long-term follow-up were lower than those obtained prior to treatment. When follow-up symptom means were compared with pretreatment means, significant (P less than 0.05) reductions were obtained on abdominal pain/tenderness, diarrhea, nausea, and flatulence.     

Prediction of outcome from cognitive-behavioral treatment of irritable bowel syndrome

The presence of a diagnosable Axis I psychiatric disorder predicted significantly (P < 0.001) lower likelihood of significant improvement among 90 irritable bowel syndrome patients given cognitive and behavioral treatments to help the disorder. Other psychological tests, including the MMPI, BDI, STAI, as well as demographic variables, failed to yield significant prediction.     

Long-term follow-up of internet-delivered exposure and mindfulness based treatment for irritable bowel syndrome

We conducted a follow-up of a previously reported study of internet-delivered cognitive behavior therapy (CBT) for IBS, based on exposure and mindfulness exercises (Ljótsson et al. (2010). Internet-delivered exposure and mindfulness based therapy for irritable bowel syndrome – a randomized controlled trial. Behaviour Research and Therapy, 48, 531–539). Seventy-five participants from the original sample of 85 (88%) reported follow-up data at 15–18 months (mean 16.4 months) after completing treatment. The follow-up sample included participants from both the original study’s treatment group and waiting list after it had been crossed over to treatment. Intention-to-treat analysis showed that treatment gains were maintained on all outcome measures, including IBS symptoms, quality of life, and anxiety related to gastrointestinal symptoms, with mainly large effect sizes (within-group Cohen’s d = 0.78–1.11). A total of fifty participants (59% of the total original sample; 52% of the original treatment group participants and 65% of the original waiting list participants) reported adequate relief of symptoms. Improvements at follow-up were more pronounced for the participants that had completed the full treatment and maintenance of improvement did not seem to be dependent on further treatment seeking. This study suggests that internet-delivered CBT based on exposure and mindfulness has long-term beneficial effects for IBS-patients.     

Cognitive therapy for irritable bowel syndrome is associated with reduced limbic activity, GI symptoms, and anxiety

This study sought to identify brain regions that underlie symptom changes in severely affected IBS patients undergoing cognitive therapy (CT). Five healthy controls and 6 Rome II diagnosed IBS patients underwent psychological testing followed by rectal balloon distention while brain neural activity was measured with O-15 water positron emission tomography (PET) before and after a brief regimen of CT. Pre-treatment resting state scans, without distention, were compared to post-treatment scans using statistical parametric mapping (SPM). Neural activity in the parahippocampal gyrus and inferior portion of the right cortex cingulate were reduced in the post-treatment scan, compared to pre-treatment (x, y, z coordinates in MNI standard space were -30, -12, -30, P=0.017; 6, 34, -8, P=0.023, respectively). Blood flow values at these two sites in the controls were intermediate between those in the pre- and post-treatment IBS patients. Limbic activity changes were accompanied by significant improvements in GI symptoms (e.g., pain, bowel dysfunction) and psychological functioning (e.g., anxiety, worry). The left pons (-2, -26, -28, P=0.04) showed decreased neural activity which was correlated with post-treatment anxiety scores. Changes in neural activity of cortical-limbic regions that subserve hypervigilance and emotion regulation may represent biologically oriented change mechanisms that mediate symptom improvement of CT for IBS.     

Two controlled evaluations of multicomponent psychological treatment of irritable bowel syndrome.

We report two controlled comparisons of a previously validated multicomponent (relaxation, thermal biofeedback, and cognitive therapy) treatment for irritable bowel syndrome (IBS) to an ostensible attention-placebo control (pseudo-meditation and EEG alpha suppression biofeedback) and to a symptom-monitoring control. In Study 1 (n = 10 per condition) there were nonsignificant trends for the multicomponent treatment to be superior to the attention-placebo condition. In Study 2 (n = 30 per condition), we found no advantage for the multicomponent treatment over the attention-placebo condition. Subjects in both treatment conditions showed significant reductions in GI symptoms, as measured by daily symptom diaries, and significant reductions in trait anxiety and depression. The GI symptom reductions held up over a 6 month follow-up. Possible explanations for the results are explored.     

A cognitive-behavioral treatment for irritable bowel syndrome using interoceptive exposure to visceral sensations

BackgroundIrritable bowel syndrome (IBS) is a chronic and debilitating medical condition with few efficacious pharmacological or psychosocial treatment options available. Evidence suggests that visceral anxiety may be implicated in IBS onset and severity. Thus, cognitive-behavioral treatment (CBT) that targets visceral anxiety may alleviate IBS symptoms.MethodsThe current study examined the efficacy of a CBT protocol for the treatment of IBS which directly targeted visceral sensations. Participants (N = 110) were randomized to receive 10 sessions of either: (a) CBT with interoceptive exposure (IE) to visceral sensations; (b) stress management (SM); or (c) an attention control (AC), and were assessed at baseline, mid-treatment, post-treatment, and follow-up sessions.ResultsConsistent with hypotheses, the IE group outperformed AC on several indices of outcome, and outperformed SM in some domains. No differences were observed between SM and AC. The results suggest that IE may be a particularly efficacious treatment for IBS.ConclusionsImplications for research and clinical practice are discussed.     

Convergence of parent checklists and child psychiatric diagnoses

This study examined the correlation between the Childrens' Behavior Questionnaire by Rutter, Tizard, and Whitmore (1970) and clinical diagnoses in a total of 1,468 in-and outpatients. The following diagnoses were considered: conduct disorder, emotional disorder, mixed disorder of conduct and emotions, and the hyperkinetic syndrome. In general, correlations were low, but subscores indicating conduct or neurotic disorders had somewhat higher correlation with these respective disorders than the hyperactivity subscore. Sensitivity figures (i.e., percentage of true positives) were moderate to low, while specificity figures (i.e., percentage of true negatives) were high. It is concluded that convergence of parent checklists and child psychiatric diagnoses in unselected samples is only moderate.     

Internet-delivered exposure and mindfulness based therapy for irritable bowel syndrome - A randomized controlled trial

The aim of this study was to investigate if cognitive behavior therapy (CBT) based on exposure and mindfulness exercises delivered via the Internet would be effective in treating participants with irritable bowel syndrome (IBS). Participants were recruited through self-referral. Eighty-six participants were included in the study and randomized to treatment or control condition (an online discussion forum). One participant was excluded after randomization. The main outcome measure was IBS-symptom severity and secondary measures included IBS-related quality of life, GI-specific anxiety, depression and general functioning. Participants were assessed at pre-treatment, post-treatment and 3 month follow-up (treatment condition only). Four participants (5% of total sample) in the treatment condition did not participate in post-treatment assessment. Participants in the treatment condition reported a 42% decrease and participants in the control group reported a 12% increase in primary IBS-symptoms. Compared to the control condition, participants in the treatment group improved on all secondary outcome measures with a large between group effect size on quality of life (Cohen’s d = 1.21). We conclude that CBT-based on exposure and mindfulness delivered via the Internet can be effective in treating IBS-patients, alleviating the total burden of symptoms and increasing quality of life.     

A controlled evaluation of group cognitive therapy in the treatment of irritable bowel syndrome

We randomized, at two sites, 210 patients with Rome II diagnosed irritable bowel syndrome (IBS), of at least moderate severity, to one of three conditions: group-based cognitive therapy (CT; n=120), psychoeducational support groups (n=46) as an active control, or intensive symptom and daily stress monitoring (n=44). One hundred eighty-eight participants completed the initial treatment. Those in symptom monitoring were then crossed over to CT. For an intent to treat analysis on a composite GI symptom measure derived from daily symptom diaries, both CT and the psychoeducational support groups were significantly more improved than those in the intensive symptom monitoring condition, but the CT and psychoeducational support group did not differ. Among treatment completers on the same composite measure of GI symptoms, again, both CT and psychoeducational support groups were statistically superior to symptom monitoring but did not differ on the symptom composite, or on any other measure. On individual IBS symptoms, both CT and psychoeducational support were statistically superior to symptom monitoring on reductions in abdominal pain and tenderness and for flatulence. Patient global ratings at the end of treatment showed the two active conditions statistically superior to symptom monitoring on change in Bowel Regularity, with CT superior to symptom monitoring on reduction in overall pain and in improvement in sense of well-being. Three-month follow-up data on 175 patients revealed maintenance of significant improvement or continued significant improvement on all IBS symptoms, including the McGill Pain Questionnaire. Group CT and psychoeducational support groups continued not to differ on any measure. We thus conclude that group CT is not superior to an attention placebo control condition.     

Visceral sensitivity as a mediator of outcome in the treatment of irritable bowel syndrome

Patients with irritable bowel syndrome (IBS) experience anxiety about visceral sensations, leading to avoidance behaviors and hypervigilance that maintain IBS symptoms. The current study used data from a clinical trial that compared a treatment aimed at reducing anxiety about visceral sensations (interoceptive exposure; IE) to an attention control (AC) and a CBT-based stress-management treatment (SM) to examine whether changes in visceral sensitivity mediated IBS symptom and quality of life outcomes. Data from participants who completed one of the three treatments (N = 76) were subjected to mediation analyses. Visceral sensitivity mediated treatment outcomes across all outcome measures and across all treatment groups, with no differences between IE and the other treatment groups. This finding suggests that psychosocial treatments for IBS may work by decreasing visceral sensitivity, and the degree to which visceral sensitivity is decreased is related to outcome, suggesting IE may be the preferable treatment option.