Synesthesia, pseudo-synesthesia, and irritable bowel syndrome

BACKGROUND AND AIMS

Synesthesia is a sensory disorder where the stimulation of one sensory modality can lead to a reaction in another which would not usually be expected to respond; for instance, someone might see a color on hearing a word such as a day of the week. Disordered perception of sensory information also appears to contribute to the pathophysiology of irritable bowel syndrome (IBS). The purpose of this exploratory study was to ascertain whether these two conditions might be linked in any way.

METHODS

Two hundred consecutive IBS outpatients were screened for synesthesia and compared with 200 matched healthy volunteers (controls). Positive responders were tested for two types of synesthesia (grapheme-color and music-color/shape) using a questionnaire which was repeated after 3 months to test for reproducibility.

RESULTS

Of the 200 IBS outpatients screened, 26 (13%) patients and six (3%) controls claimed to be synesthetic (P < 0.001). Reproducibility was more variable in IBS patients than controls but despite this variability, 15 (7.5%) patients compared with 5 (2.5%) controls had greater than 75% consistency (P = 0.036), and 19 (9.5%) patients and 6 (3%) controls had greater than 50% consistency (P = 0.012). A reproducibility of less than 50% was observed in seven (3.5%) patients and no controls (0%) (P = 0.015), and these individuals were classified as having pseudo-synesthesia.

CONCLUSION

IBS patients clearly differ from controls in terms of claiming to have synesthetic experiences. These results justify additional studies on the relationship between IBS and synesthesia to further understand the neural mechanisms underpinning these two conditions and to establish whether they may be linked.

Unraveling functional abdominal bloating and distension: the role of thoraco-abdominal accommodation and a physical sign to aid its detection

Bloating and distension are common complaints in patients with irritable bowel syndrome of which the cause has remained elusive, although it has been shown that the obvious explanation of excessive gas is unlikely. The recent application of technologies such as the gas challenge technique, abdominal inductance plethysmography, CT scanning, as well as electromyography of the diaphragm and anterior abdominal wall, have allowed the situation to be slowly unraveled. It is now seems probable that the pathophysiology of bloating and distension are subtly different with the former having a sensory component whereas mechanical factors, such as disordered abdominal accommodation, contribute more to the latter.

Visceral hypersensitivity in endometriosis: a new target for treatment?

OBJECTIVE

In women presenting to gynaecological clinics with lower abdominal pain, the cause is frequently attributed to endometriosis irrespective of whether it is found to be minimal or extensive at laparoscopy. Irritable bowel syndrome (IBS) is also common in this setting, and it was speculated that the visceral hypersensitivity associated with this condition might be amplifying the symptoms of endometriosis.

METHODS

Visceral sensitivity to balloon distension, symptoms and psychological status were assessed following laparoscopy in 20 women with minimal to mild endometriosis, 20 with moderate to severe endometriosis, 20 with laparoscopy negative abdominal pain and 20 asymptomatic women undergoing laparoscopic sterilisation who acted as controls, and compared with 20 women with IBS.

RESULTS

Compared with controls, patients with minimal to mild and moderate to severe endometriosis had a higher prevalence of symptoms consistent with IBS (0% vs 65% and 50%, respectively, p<0.001) with significantly lower mean pain thresholds (39.5 mm Hg (95% CI 36.0 to 43.0) vs 28.1 mm Hg (95% CI 24.5 to 31.6), p=0.001 and 28.8 mm Hg (95% CI 24.9 to 32.6), p=0.002) not explained by differences in rectal compliance. Patients with laparoscopy negative pain had symptoms and visceral sensitivity similar to patients with IBS. Controls undergoing laparoscopy had normal sensitivity, indicating that the laparoscopic procedure was not inducing hypersensitivity.

CONCLUSION

Visceral hypersensitivity is extremely common in endometriosis and could be intensifying the pain. This finding might explain why mildly affected individuals often complain of severe symptoms out of proportion to the extent of their disease. This study has introduced a completely new concept into the understanding of pain in endometriosis and could open up new opportunities for treatment.

Abdominal bloating and distension: what is the role of the microbiota

Most patients with irritable bowel syndrome complain of a sensation of an increase in pressure within their abdomen during the course of the day which is called bloating and, in approximately half of these individuals, this symptom is accompanied by an actual increase in abdominal girth, which is referred to as distension. The pathophysiology of these two phenomena is somewhat different and it is now recognised that a whole variety of overlapping mechanisms are involved. Some of these are potentially amenable to treatment by modification of the bacterial flora of the gut and this article reviews the evidence for this.

A randomised controlled trial on hypnotherapy for irritable bowel syndrome: design and methodological challenges (the IMAGINE study)

BACKGROUND

Irritable Bowel Syndrome (IBS) is a common gastro-intestinal disorder in primary and secondary care, characterised by abdominal pain, discomfort, altered bowel habits and/or symptoms of bloating and distension. In general the efficacy of drug therapies is poor. Hypnotherapy as well as Cognitive Behaviour Therapy and short Psychodynamic Therapy appear to be useful options for patients with refractory IBS in secondary care and are cost-effective, but the evidence is still limited. The IMAGINE-study is therefore designed to assess the overall benefit of hypnotherapy in IBS as well as comparing the efficacy of individual versus group hypnotherapy in treating this condition.

METHODS/DESIGN

The design is a randomised placebo-controlled trial. The study group consists of 354 primary care and secondary care patients (aged 18-65) with IBS (Rome-III criteria). Patients will be randomly allocated to either 6 sessions of individual hypnotherapy, 6 sessions of group hypnotherapy or 6 sessions of educational supportive therapy in a group (placebo), with a follow up of 9 months post treatment for all patients. Ten hospitals and four primary care psychological practices in different parts of The Netherlands will collaborate in this study. The primary efficacy parameter is the responder rate for adequate relief of IBS symptoms. Secondary efficacy parameters are changes in the IBS symptom severity, quality of life, cognitions, psychological complaints, self-efficacy as well as direct and indirect costs of the condition. Hypnotherapy is expected to be more effective than the control therapy, and group hypnotherapy is expected not to be inferior to individual hypnotherapy.

DISCUSSION

If hypnotherapy is effective and if there is no difference in efficacy between individual and group hypnotherapy, this group form of treatment could be offered to more IBS patients, at lower costs.

TRIAL REGISTRATION NUMBER

ISRCTN: ISRCTN22888906.

The LUCK study: Laxative Usage in patients with GP-diagnosed Constipation in the UK, within the general population and in pregnancy. An epidemiological study using the General Practice Research Database (GPRD)

BACKGROUND

Despite the high prevalence of constipation and its related public health implications, there is relatively little research available on the condition from large epidemiological studies. The aim of this study was to investigate the epidemiology of general practitioner (GP)-diagnosed constipation and the prescribing trends for laxatives in the UK, within the general population and during pregnancy.

METHODS

A cohort study for the period from 2005 to 2009 was performed using the UK primary care database (General Practice Research Database), which contains information on over 3 million individuals.

RESULTS

The prevalence of GP-diagnosed constipation ranged from 12 per 1000 persons in 2005 (0.012 per person year) to 12.8 per 1000 in 2009 (0.013 per person year). The prevalence was almost twice as high in women as in men, and was higher in older patients. In 2005 the most commonly prescribed laxatives were lactulose (37%), senna (26%), macrogol (19%), ispaghula (6%), docusate sodium (5%), bisacodyl (4%) and glycerol suppositories (2%). By 2009, this pattern had changed: macrogol (31%), lactulose (29%), senna (22%), ispaghula (5%), docusate sodium (6%), bisacodyl (3%) and glycerol suppositories (3%). In pregnancy, lactulose accounted for 81% of laxative use in 2005, falling to 64% by 2009. In contrast, macrogol use in pregnancy rose from 13% in 2005 to 32% in 2009.

CONCLUSIONS

GP-diagnosed constipation is common, accounting for a large number of consultations. Laxative prescribing trends have changed over the 5-year study period, prescriptions for macrogol becoming increasingly common and prescriptions for lactulose and senna less common. Macrogol also appears to have been replacing lactulose for treating constipation in pregnant women.

Do probiotics improve symptoms in patients with irritable bowel syndrome?

There is increasing evidence that inflammation or a disturbance of the flora within the gut might contribute to the pathogenesis of irritable bowel syndrome (IBS), at least in a proportion of cases. As a consequence it has been speculated that, as some probiotic bacteria have a range of anti-inflammatory and immunomodulatory properties, the administration of such organisms might prove to be beneficial in this condition. It has to be acknowledged that the quality and design of trials of probiotics in IBS has been somewhat variable but the majority have shown benefit, although some bacteria appear to be more effective than others. More recent studies using Bifidobacterium infantis 35624 and Bifidobacterium lactis DN-173-010 have given particularly encouraging results. Issues for the future include determining which organisms are most effective, defining optimal doses, comparing methods of delivery and assessing the role of mixtures or the addition of prebiotics.

Mood color choice helps to predict response to hypnotherapy in patients with irritable bowel syndrome

BACKGROUND

Approximately two thirds of patients with irritable bowel syndrome (IBS) respond well to hypnotherapy. However, it is time consuming as well as expensive to provide and therefore a way of predicting outcome would be extremely useful. The use of imagery and color form an integral part of the hypnotherapeutic process and we have hypothesised that investigating color and how it relates to mood might help to predict response to treatment. In order to undertake this study we have previously developed and validated a method of presenting colors to individuals for research purposes called the Manchester Color Wheel (MCW). Using this instrument we have been able to classify colors into positive, neutral and negative shades and this study aimed to assess their predictive role in hypnotherapy.

METHODS

156 consecutive IBS patients (aged 14-74, mean 42.0 years, 127 (81%) females, 29 (19%) males) were studied. Before treatment, each patient was asked to relate their mood to a color on the MCW as well as completing the IBS Symptom Severity Score, the Hospital Anxiety and Depression (HAD) Scale, the Non-colonic Symptom Scale, the Quality of Life Scale and the Tellegen Absorption Scale (TAS) which is a measure of hypnotisability. Following hypnotherapy all these measures were repeated with the exception of the TAS.

RESULTS

For patients with a positive mood color the odds of responding to hypnotherapy were nine times higher than that of those choosing either a neutral or negative color or no color at all (odds ratio: 8.889; p = 0.042). Furthermore, a high TAS score and the presence of HAD anxiety also had good predictive value (odds ratio: 4.024; p = 0.092, 3.917; p < 0.001 respectively) with these markers and a positive mood color being independent of each other. In addition, these factors could be combined to give an even stronger prediction of outcome. Twice as many responders (63, 77.8%) had a positive mood color or were anxious or had a high TAS score compared with 32 (42.7%) without these factors (p < 0.001).

CONCLUSION

A positive mood color, especially when combined with HAD anxiety and a high TAS score, predict a good response to hypnotherapy.

The Patient Health Questionnaire 12 Somatic Symptom scale as a predictor of symptom severity and consulting behaviour in patients with irritable bowel syndrome and symptomatic diverticular disease

BACKGROUND

Anxiety, depression and nongastrointestinal symptoms are often prominent in irritable bowel syndrome (IBS), but their relative value in patient management has not been quantitatively assessed. We modified the Patient Health Questionnaire 15 (PHQ-15) by excluding three gastrointestinal items to create the PHQ-12 Somatic Symptom (PHQ-12 SS) scale.

AIMS

To compare the value of the PHQ-12 SS scale with the Hospital Anxiety and Depression (HAD) scale in predicting symptoms and patient behaviour in IBS and diverticular disease.

METHODS

We compared 151 healthy volunteers (HV), 319 IBS patients and 296 patients with diverticular disease (DD), 113 asymptomatic [ASYMPDD] and 173 symptomatic DD (SYMPDD).

RESULTS

Patient Health Questionnaire 12 SS scores for IBS and SYMPDD were significantly higher than HV. Receiver-operator curves showed a PHQ-12 SS >6, gave a sensitivity for IBS of 66.4% with a specificity of 94.7% and a positive likelihood ratio (PLR) = 13.2, significantly better than that associated with an HAD anxiety score >7, PLR = 3.0 and depression score >7 PLR = 6.5. PHQ-12 SS correlated strongly with IBS severity scale and GP visits in both IBS and DD.

CONCLUSION

The PHQ-12 SS scale is a useful clinical tool which correlates with patient behaviour in both IBS and symptomatic DD.

The Manchester Color Wheel: development of a novel way of identifying color choice and its validation in healthy, anxious and depressed individuals

Background

For the purposes of our research programme we needed a simple, reliable and validated method for allowing choice of a color in response to a series of questions. On reviewing the literature no such instrument was available and this study aimed to rectify this situation. This was achieved by developing a simple method of presenting a series of colors to people validating it in healthy volunteers and in individuals where color choice might be distorted, namely anxiety and depression.

Methods

A series of different presentations of four shades of eight colors and grey, as well as black and white were evaluated. 'Mood', 'favourite' and 'drawn to' colors were assessed in 105 healthy, 108 anxious and 110 depressed participants. The positive, neutral or negative attribution of these colors was recorded in a further 204 healthy volunteers.

Results

The circular presentation of colors was most favoured (Color Wheel). Yellow was the most 'drawn to' color and blue the commonest 'favourite' color in all subjects. Yellow was most often associated with a normal mood and grey with an anxious or depressed mood. Different shades of the same color had completely different positive or negative connotations. Reproducibility was exceptionally high when color choice was recorded in positive, neutral or negative terms.

Conclusions

The Color Wheel could be used to assess health status, mood or even treatment outcome in a variety of clinical situations. It may also have utility in circumstances where verbal communication may not be optimal, such as with children.

Reactivity to images in health and irritable bowel syndrome

BACKGROUND

We have been using a medical artist to record and paint the images patients have of their irritable bowel syndrome (IBS) and have hypothesized that the reaction to such images might differ in health and IBS, which could have practical implications for future research.

AIM

To examine reactivity to images in health and IBS.

METHODS

Twelve paintings of IBS were shown to 70 patients to determine the four most evocative images. The spontaneous response to these images and four 'non-IBS painful' and four neutral paintings was assessed in another 100 IBS patients and 100 controls. The prompted reaction in terms of whether an image evoked the notion of pain, bloating or discomfort and to what degree was also recorded.

RESULTS

Four images depicting bloating and pain scored the highest. These IBS images triggered significantly different reactivity between patients and controls in terms of their spontaneous and prompted responses. Even 'non-IBS painful' and neutral images resulted in exaggerated and frequently significantly different responses in patients than in controls.

CONCLUSIONS

Visual hypersensitivity appears to be another manifestation of the tendency of IBS patients to react adversely to a variety of endogenous and exogenous stimuli. Identifying how individuals relate to different images might also give useful insights into understanding gastrointestinal symptoms.

5-hydroxytryptamine signalling in irritable bowel syndrome with diarrhoea: effects of gender and menstrual status

BACKGROUND

Symptomatology and physiology differ between men and women and across the menstrual cycle in irritable bowel syndrome (IBS). Ovarian hormones influence 5-hydroxytryptamine (5-HT), an amine known to play a role in gut motor-sensory function.

AIM

To assess the effects of gender and menstrual status on platelet-depleted plasma (PDP) 5-HT concentration in IBS patients with diarrhoea (IBS-D) patients compared with healthy volunteers (HV).

METHODS

Platelet-depleted plasma 5-HT concentrations were assessed under fasting and fed conditions in 73 IBS-D patients (aged 18-58 years; 18 men) and 64 HV (aged 18-50 years; 24 men). Women were divided into those with low or high progesterone/oestrogen (P/O) levels.

RESULTS

Irritable bowel syndrome patients with diarrhoea had higher PDP 5-HT concentrations than HV under fasting (P = 0.002) and fed (P = 0.049) conditions. This was particularly related to IBS-D men having higher PDP 5-HT concentrations than healthy controls (P = 0.002). Moreover, PDP 5-HT concentrations in IBS-D women with low P/O levels were similar to healthy controls.

CONCLUSIONS

Similar to IBS-D women with high P/O levels, IBS-D men also have raised PDP 5-HT concentrations. 5-HT concentration normalizes at menses in IBS-D women, suggesting a shift in the mechanisms responsible for abnormal 5-HT signalling in these patients.

Soluble or insoluble fibre in irritable bowel syndrome in primary care? Randomised placebo controlled trial

OBJECTIVE

To determine the effectiveness of increasing the dietary content of soluble fibre (psyllium) or insoluble fibre (bran) in patients with irritable bowel syndrome.

DESIGN

Randomised controlled trial.

SETTING

General practice.

PARTICIPANTS

275 patients aged 18-65 years with irritable bowel syndrome.

INTERVENTIONS

12 weeks of treatment with 10 g psyllium (n=85), 10 g bran (n=97), or 10 g placebo (rice flour) (n=93).

MAIN OUTCOME MEASURES

The primary end point was adequate symptom relief during at least two weeks in the previous month, analysed after one, two, and three months of treatment to assess both short term and sustained effectiveness. Secondary end points included irritable bowel syndrome symptom severity score, severity of abdominal pain, and irritable bowel syndrome quality of life scale.

RESULTS

The proportion of responders was significantly greater in the psyllium group than in the placebo group during the first month (57% v 35%; relative risk 1.60, 95% confidence interval 1.13 to 2.26) and the second month of treatment (59% v 41%; 1.44, 1.02 to 2.06). Bran was more effective than placebo during the third month of treatment only (57% v 32%; 1.70, 1.12 to 2.57), but this was not statistically significant in the worst case analysis (1.45, 0.97 to 2.16). After three months of treatment, symptom severity in the psyllium group was reduced by 90 points, compared with 49 points in the placebo group (P=0.03) and 58 points in the bran group (P=0.61 versus placebo). No differences were found with respect to quality of life. Fifty four (64%) of the patients allocated to psyllium, 54 (56%) in the bran group, and 56 (60%) in the placebo group completed the three month treatment period. Early dropout was most common in the bran group; the main reason was that the symptoms of irritable bowel syndrome worsened.

CONCLUSIONS

Psyllium offers benefits in patients with irritable bowel syndrome in primary care.

TRIAL REGISTRATION

Clinical trials NCT00189033.

Soluble or insoluble fibre in irritable bowel syndrome in primary care? Randomised placebo controlled trial

OBJECTIVE

To determine the effectiveness of increasing the dietary content of soluble fibre (psyllium) or insoluble fibre (bran) in patients with irritable bowel syndrome.

DESIGN

Randomised controlled trial.

SETTING

General practice.

PARTICIPANTS

275 patients aged 18-65 years with irritable bowel syndrome.

INTERVENTIONS

12 weeks of treatment with 10 g psyllium (n=85), 10 g bran (n=97), or 10 g placebo (rice flour) (n=93).

MAIN OUTCOME MEASURES

The primary end point was adequate symptom relief during at least two weeks in the previous month, analysed after one, two, and three months of treatment to assess both short term and sustained effectiveness. Secondary end points included irritable bowel syndrome symptom severity score, severity of abdominal pain, and irritable bowel syndrome quality of life scale.

RESULTS

The proportion of responders was significantly greater in the psyllium group than in the placebo group during the first month (57% v 35%; relative risk 1.60, 95% confidence interval 1.13 to 2.26) and the second month of treatment (59% v 41%; 1.44, 1.02 to 2.06). Bran was more effective than placebo during the third month of treatment only (57% v 32%; 1.70, 1.12 to 2.57), but this was not statistically significant in the worst case analysis (1.45, 0.97 to 2.16). After three months of treatment, symptom severity in the psyllium group was reduced by 90 points, compared with 49 points in the placebo group (P=0.03) and 58 points in the bran group (P=0.61 versus placebo). No differences were found with respect to quality of life. Fifty four (64%) of the patients allocated to psyllium, 54 (56%) in the bran group, and 56 (60%) in the placebo group completed the three month treatment period. Early dropout was most common in the bran group; the main reason was that the symptoms of irritable bowel syndrome worsened.

CONCLUSIONS

Psyllium offers benefits in patients with irritable bowel syndrome in primary care.

TRIAL REGISTRATION

Clinical trials NCT00189033.

Bloating and distension in irritable bowel syndrome: the role of gastrointestinal transit

OBJECTIVES

Patients with irritable bowel syndrome and constipation (IBS-C) show more abdominal distension than do those with diarrhea. Because constipation is often associated with delayed gastrointestinal transit, this study aimed at establishing whether patients with delayed transit show more distension and bloating than do those with normal transit.

METHODS

Abdominal girth was recorded for 24 h using abdominal inductance plethysmography (AIP) in 30 IBS-C (Rome II criteria) patients (aged 18-68 years; 27 women) and in 30 healthy volunteers (21-58 years of age; 26 women). Within 2 weeks of this recording, orocecal and colonic transits were assessed. Orocecal transit was determined from the increase in breath hydrogen after a standard meal, and colonic transit from the number of radio-opaque markers identified on a plain abdominal X-ray. Bloating severity was assessed hourly during AIP recording using a 0-5 scale.

RESULTS

IBS-C patients showed more bloating and distension than did healthy volunteers (P<0.001). They also had prolonged colonic (P<0.001) and orocecal (P=0.05) transits than did healthy volunteers, such that 47 and 17%, respectively, had colonic and orocecal transit times greater than the normal reference range. Those with delayed colonic (P=0.025) and orocecal (P=0.13) transits had greater distension but not bloating (P=0.63 and P=0.48, respectively) compared with those with normal transit. Moreover, distension directly correlated with orocecal (r=0.40; P=0.03) and colonic (r=0.51; P=0.004) transit times and inversely with stool consistency (r=-0.43; P=0.07).

CONCLUSIONS

IBS-C patients with delayed transit show greater abdominal distension than do those with normal transit. Therefore, drugs that accelerate transit may be expected to alleviate this troublesome problem.

Hypnotherapy for functional gastrointestinal disorders: a review

Patients with functional gastrointestinal disorders, such as irritable bowel syndrome, functional dyspepsia, and noncardiac chest pain, can suffer from a range of severe symptoms that often substantially erode quality of life. Unfortunately, these conditions are notoriously difficult to treat, with many patients failing to improve despite being prescribed a wide variety of conventional medications. As a consequence, the potential benefits of hypnotherapy have been explored with evidence that this approach not only relieves symptoms but also appears to restore many of the putative psychological and physiological abnormalities associated with these conditions toward normal. These observations suggest that this form of treatment has considerable potential in aiding the management of functional gastrointestinal disorders and should be integrated into the ongoing medical care that these patients are receiving.

Using art to help understand the imagery of irritable bowel syndrome and its response to hypnotherapy

A medical artist asked 109 patients if they had an image of their IBS pre- and posthypnotherapy, making precise watercolor paintings of any images described. Results were related to treatment outcome, symptoms, anxiety, depression, and absorption (hypnotizability); 49% of patients had an image, and a wide variety were recorded and painted. Imagery was significantly associated with gender (p < .05), anxiety (p < .05), noncolonic symptomatology (p < .05), and absorption (p = .001); 57.8% of responders compared with 35.5% of nonresponders to hypnotherapy had an image of their disease (p < .05) before treatment, and color images were associated with better outcomes (p = .05) than monochrome ones. All images changed in responders, often becoming more nonspecific in nature. Inquiring about IBS imagery helps to identify potential responders and nonresponders to hypnotherapy and may also provide insights into how patients think about their illness.

Clinical trial: the effects of a fermented milk product containing Bifidobacterium lactis DN-173 010 on abdominal distension and gastrointestinal transit in irritable bowel syndrome with constipation

BACKGROUND

A sensation of abdominal swelling (bloating) and actual increase in girth (distension) are troublesome features of irritable bowel syndrome (IBS), which is more common in patients with constipation, especially those with delayed transit.

AIM

To establish whether a fermented dairy product containing Bifidobacterium lactis DN-173 010 reduces distension in association with acceleration of gastrointestinal transit and improvement of symptoms in IBS with constipation.

METHODS

A single centre, randomized, double-blind, controlled, parallel group study in which patients consumed the test product or control product for 4 weeks. Distension, orocaecal and colonic transit and IBS symptoms were assessed on an intention-to-treat population of 34 patients.

RESULTS

Compared with control product, the test product resulted in a significant reduction in the percentage change in maximal distension [median difference - 39%, 95% CI (-78, -5); P = 0.02] and a trend towards reduced mean distension during the day [-1.52 cm (-3.33, 0.39); P = 0.096]. An acceleration of orocaecal [-1.2 h (-2.3,0); P = 0.049] as well as colonic [-12.2 h (-22.8, -1.6); P = 0.026] transit was observed and overall symptom severity [-0.5 (-1.0, -0.05); P = 0.032] also improved.

CONCLUSIONS

This probiotic resulted in improvements in objectively measured abdominal girth and gastrointestinal transit, as well as reduced symptomatology. These data support the concept that accelerating transit is a useful strategy for treating distension.