Unsubtyped Irritable Bowel Syndrome Research Articles

Prevalence and Burden of Illness of Rome IV Irritable Bowel Syndrome in the United States: Results From a Nationwide Cross-Sectional Study

The estimated prevalence of irritable bowel syndrome (IBS) using Rome IV criteria in the United States (US) ranges from 4.7% to 5.3%, although these estimates arise from studies with relatively small sample sizes. This study assessed the prevalence of IBS and its associated burden of illness using a nationally representative data set with nearly 89,000 people in the US. From May 3 to June 24, 2020, we performed an online survey described to participating adults aged ≥18 years old as a "national health survey." We recruited a representative sample of people in the US to complete the survey, which included the Rome IV IBS questionnaire, National Institutes of Health Patient-Reported Outcome Measurement Information System (PROMIS) gastrointestinal scales, and questions on health care-seeking behavior. Overall, 88,607 people completed the survey, of whom 5414 (6.1%) met Rome IV IBS criteria: mixed IBS (n= 1838 [33.9%]), constipation-predominant IBS (n= 1819 [33.6%]), diarrhea-predominant IBS (n= 1521 [28.1%]), and unsubtyped IBS (n= 236 [4.4%]). Women had higher odds for IBS compared with men, whereas racial/ethnic minorities had lower odds for IBS vs non-Hispanic Whites. Across the 3 main subtypes, 68.2% to 73.2% of people reported ever seeking care for their IBS symptoms, whereas 53.8% to 58.9% did so in the past 12 months. In this nationwide US survey, we found that Rome IV IBS is slightly more prevalent (6.1%) vs prior estimates (4.7%-5.3%). Additional research is needed to determine whether this higher prevalence is in part due to the coronavirus disease 2019 pandemic during which this study was conducted.

The association between dietary total antioxidant capacity and odds and severity of irritable bowel syndrome among Iranian adults: a cross-sectional study

BackgroundLittle evidence is available in terms of the role of dietary antioxidants in the management of irritable bowel syndrome (IBS) disease. This study aimed to examine the association between dietary total antioxidant capacity (dTAC) and odds of IBS and its severity.MethodsThis cross-sectional study was conducted on 3,362 Iranian adults who were referred to health centers in Isfahan province, Iran. Participants' dietary intakes were collected using a semi-quantitative validated food frequency questionnaire (DS-FFQ). The dTAC was measured by the ferric-reducing antioxidant power (FRAP) method. Multivariable binary or ordinal logistic regression analyses were performed to estimate any associations between dTAC and odds of IBS, IBS severity, and IBS subtypes.ResultsThe average age and BMI of the participants and dTAC score were 36.3 ± 7.87 year, 24.9 ± 3.82 kg/m2. The prevalence of IBS, IBS with constipation (IBS-C), IBS with diarrhoea (IBS-D), mixed IBS (IBS-M), and un-subtyped IBS (IBS-U) were 22.2, 7.5, 4.6, 3.8, and 6.2%, respectively. In crude and adjusted models, the results did not show any significant association between dTAC and odds of IBS among whole and gender-age stratified populations. Being in the third compared with the first tertile of dTAC was not also significantly associated with odds of IBS severity. Besides, there were no significant associations between dTAC and odds of IBS-C, IBS-D, IBS-M, and IBS-U.ConclusionThis study indicates that dTAC may not be associated with the odds of IBS and its severity even after stratification for gender and body mass index.

Habitual FODMAP Intake in Relation to Symptom Severity and Pattern in Patients with Irritable Bowel Syndrome.

Restricting intake of FODMAPs (Fermentable Oligo-, Di-, Monosaccharides and Polyols) is used as treatment for irritable bowel syndrome (IBS). However, whether habitual FODMAP consumption correlates to symptom severity, and if this relationship differs among IBS subtypes, is unclear. The aim was to study the relationship between habitual FODMAP intake and symptom severity. A total of 189 patients with IBS—IBS with constipation (IBS-C) n = 44 (22.3%), IBS with diarrhea (IBS-D) n = 54 (27.4%), mixed IBS (IBS-M) n = 46 (23.4%) and unsubtyped IBS (IBS-U) n = 46 (23.4%)—recorded food intake during four days. Symptom severity was measured with the IBS severity scoring system (IBS-SSS). For FODMAP intake, a lower lactose intake was noted among women with IBS-D, p = 0.009. In women, there was a statistically significant relationship between energy-adjusted FODMAP intake and IBS-SSS (r = 0.21, p = 0.003). This was mainly driven by the subtype IBS-U, where excess fructose intake accounted for 19.9% of explained variance in IBS-SSS (p = 0.007). This study demonstrates small differences in FODMAP intake among IBS patients with different subtypes. Association between IBS symptoms and FODMAP intake was most prominent in unsubtyped IBS. However, patients who are intolerant to certain FODMAPs may already have reduced their FODMAP intake, and this warrants future cohort or experimental studies to uncover.

Psychological profiles of irritable bowel syndrome patients with different phenotypes.

Background/Aims Abnormal psychological profiles are frequently found in patients with functional gastrointestinal disorders (FGIDs). The present study aimed to evaluate the psychological profiles of FGID patients with irritable bowel syndrome (IBS), and IBS phenotypes.Methods In 608 FGID patients, including 235 with IBS, have filled a Rome III questionnaire and the French version of the Minnesota Multiphasic Personality Inventory 2. Data analysis was performed using univariate analysis and multivariate logistic regression.Results This study shows that IBS patients have abnormal psychological profiles with more significant symptom exaggeration and decreased test defensiveness than non-IBS patients. They have a significantly higher score for all clinical scales. Logistic regression analysis showed in IBS patients a decrease of body mass index (P= 0.002), and test defensiveness score K (P= 0.001) and an increase of Hypochondriasis (P< 0.001) and Masculinity-Femininity scale (P= 0.018). By comparison with non-IBS patients, IBS-constipation, IBS-diarrhea, and mixed IBS patients have increased Hypochondriasis value and Depression score, mixed IBS patients have higher Psychasthenia score and higher Hypomania score. No item was significantly different in the IBS-unspecified group.Conclusions This study shows that IBS patients have different psychological profiles than other FGID patients and that psychological characteristics are associated with IBS phenotypes except for patients with unsubtyped IBS.

Does frequency of restless legs syndrome and poor sleep quality increase with age in irritable bowel syndrome?

Irritable bowel syndrome (IBS) is a common gastrointestinal disease which leads to a reduction in the quality of life. Restless legs syndrome (RLS) and the incidence of poor sleep quality (PSQ) are known to increase in IBS. In this study, we aimed to investigate the prevalence and association of RLS and PSQ in a young population. A total of 112 IBS patients (46 constipation predominant IBS, 17 diarrhea predominant IBS, 23 mixed IBS and 26 unsubtyped IBS) and 106 healthy controls were included in the study. The Pittsburgh Sleep Quality Index (PSQI) and the 2012 revised diagnostic criteria of the International Restless Legs Syndrome Study Group were used in the groups. In the patients with IBS and the control group, the respective results obtained were as follows: presence of PSQ 16 (13.4%) and 5 (4.7%) and presence of RLS 10 (8.9%) and 4 (3.7%), respectively. There were significant differences between the two groups in terms of these values. According to the PSQI, the mean global PSQI scores of patients with IBS and control group were 7.61±3.9 and 4.5±3.7, respectively (P=0.01). While PSQ was detected in 21 out of 218 participants, RLS was detected in 14. PSQ and RLS coexisted in nine of the participants and all of them were IBS patients. Previous studies and our study reveal that the frequency of RLS and PSQ increases in IBS. However, this result is a lower rate compared to previous studies. The controlled and prospective studies with larger numbers of cases which demonstrate the real frequency.

Maladjustment to Academic Life and Employment Anxiety in University Students with Irritable Bowel Syndrome

The present study tested our hypothesis that university students with irritable bowel syndrome (IBS) may experience less satisfactory academic lives than those of students without IBS. We also verified the hypothesis that university students with IBS might have higher employment anxiety than students without IBS might. We conducted a cross-sectional study of 1,686 university students. Presence or absence of IBS was assessed via the Rome III Questionnaire. Two original items were used to evaluate academic life. The prevalence rates of IBS with diarrhea, IBS with constipation, mixed IBS, and unsubtyped IBS in the study population were 5%, 2%, 10%, and 3%, respectively. Regarding academic life, the proportions of participants who experienced maladjustment and employment anxiety were 29% and 50%, respectively. After adjusting for age, sex, and faculty, the odds ratios for maladjustment and employment anxiety were significantly higher in students who screened positively, relative to those who screened negatively, for IBS (OR, 1.62; 95% CI, 1.24–2.21; OR, 2.16; 95% CI, 1.68–2.81, respectively). In conclusion, maladjustment and anxiety over future employment were higher in university students with IBS relative to those without.

Subtypes of Irritable Bowel Syndrome in Children and Adolescents

Pharmacologic treatments for irritable bowel syndrome (IBS) and medical management of symptoms are increasingly based on IBS subtype, so it is important to accurately differentiate patients. Few studies have classified subtypes of pediatric IBS, and conclusions have been challenged by methodologic limitations. We performed a prospective study to investigate the distribution of IBS subtypes among children and adolescents based on stool diary information, and compared subtypes according to demographic and pain characteristics. We studied 129 subjects, ages 7 to 18 years (mean age, 11.4 ± 2.8 y; 60.5% female; 69.0% white) who met Pediatric Rome III IBS criteria and were part of larger studies of children with functional gastrointestinal disorders, recruited from primary and tertiary care centers. Children completed daily pain and stool diaries for 2 weeks. Participants were assigned IBS subtypes based on their reported stool information per adult Rome III criteria. IBS subtypes were compared for demographic variables and pain characteristics. IBS with constipation was the most common subtype of the disorder (58.1% of subjects), whereas mixed IBS was the least common (2.3% of subjects); 34.1% of subjects were unsubtyped IBS and 5.4% had IBS with diarrhea. The groups of different IBS subtypes did not differ significantly by sex, age, ethnicity, or pain characteristics. In contrast to adults, in children, IBS with constipation and unsubtyped IBS are the most common subtypes, whereas IBS with diarrhea and mixed IBS are less common. Demographic and pain characteristics cannot distinguish subtypes.

Prevalence of celiac disease in Iranian patients with irritable bowel syndrome: A cross‐sectional study

This study was aimed to determine the prevalence of celiac disease (CD) in irritable bowel syndrome (IBS) and its subtypes in a group of Iranian patients. From March 2007 to June 2009, 465 consecutive patients who were referred to the gastroenterology clinic of Jundishapur University of Medical Sciences and fulfilled the Rome III criteria for IBS were included. Immunoglobulin A (IgA) anti-tissue transglutaminase (IgA-tTG) and anti-gliadin antibody (AGA) levels were measured. CD was confirmed by gastroduodenoscopy and biopsy in patients with abnormal antibodies. Five patients had only elevated IgA-tTG, 26 with only elevated AGA, and in 16 patients abnormal results for both antibodies were reported. Duodenal biopsies from these 47 patients confirmed CD in 13 (2.8%, 95% CI 1.6-4.0%) according to the Marsh criteria. Two CD patients had normal IgA-tTG concentrations while only one patient with normal AGA was proven to have CD. CD was most prevalent in unsubtyped IBS (4.9%, 95% CI 1.1-8.7%), followed by mixed IBS (4.7%, 95% CI 0.3-9.1%). In multiple comparison, CD was less common in diarrhea-predominant IBS than in unsubtyped IBS, although this did not reach statistical significance (1.0% vs. 4.9%, P = 0.057). CD in unsubtyped IBS had a growing trend to be more common than in diarrhea-predominant IBS. Evaluation of IBS patients for CD is advisable.

Abdominal pain localization is associated with non-diarrheic Rome III functional gastrointestinal disorders

Abdominal pain is common in patients with functional bowel disorders (FBDs). The aim of this study was to characterize the predominant sites of abdominal pain associated with FBD subtypes, as defined by the Rome III criteria. A total of 584 consecutive patients attending FBD consultations in a tertiary center participated in the study. Stool form, abdominal pain location (nine abdominal segments), and pain intensity (10-point Likert scale) during the previous week were recorded. Logistic regression analysis was used to characterize the association of abdominal pain sites with specific FBD subtypes. FBDs were associated with predominant pain sites. Irritable bowel syndrome (IBS) with constipation was associated with pain in the left flank and patients were less likely to report pain in the right hypochondrium. Patients with functional constipation reported pain in the right hypochondrium and were less likely to report pain in the left flank and left iliac site. IBS with alternating constipation and diarrhea was associated with pain in the right flank, and unsubtyped IBS with pain in the hypogastrium Patients with functional abdominal pain syndrome reported the lower right flank as predominant pain site. Patients with unspecified FBDs were least likely to report pain in the hypogastrium. Patients with functional diarrhea, IBS with diarrhea, or functional bloating did not report specific pain sites. The results from this study provide the basis for developing new criteria allowing for the identification of homogeneous groups of patients with non-diarrheic FBDs based on characteristic sites of pain.

Ultrasonographic Assessment of Liquid Gastric Emptying and Antral Motility According to the Subtypes of Irritable Bowel Syndrome in Children

Gastric motor abnormalities have been reported in adults with irritable bowel syndrome (IBS), commonly in constipation-predominant IBS (IBS-C); however, such studies are uncommon in children. Furthermore, differences of gastric motility have not been studied in children with different IBS subtypes. Seventy-six children (33 [43%] boys, age 4-14 years, mean 7.9 years, SD 3.0 years) fulfilling Rome III criteria for IBS and 20 healthy controls (8 [40%] boys, age 4-14 years, mean 8.4 years, SD 3.0 years) were recruited (diarrhea-predominant IBS=21, IBS-C=31, mixed IBS=19, and unsubtyped IBS=5). Liquid gastric emptying rate (GER) and antral motility were assessed using an ultrasound method. Average GER (43.8% vs 66.2% in controls), amplitude of antral contractions (56.4% vs 89%), and antral motility index (5.1 vs 8.3) were lower and fasting antral area (1.6 vs 0.6) was higher in patients with IBS (P<0.0001). Frequency of antral contractions F (8.9 vs 9.3) did not show a significant difference. Patients exposed to stressful events had a significantly lower GER, compared to those not exposed to such events (P=0.03). Gastric motility parameters had no correlation with severity of symptoms. GER (42.6%, 46.3%, 39.6%), fasting antral area (1.4 cm², 1.8 cm², 1.8 cm²), amplitude of antral contractions (53%, 58.9%, 51.8%), frequency of antral contractions (8.7, 8.9, 9.2), and antral motility index (4.7, 5.3, 4.8) were not different among diarrhea-predominant IBS, IBS-C, and mixed IBS (P>0.05). GER and antral motility parameters were significantly impaired in children with IBS compared with controls. GER and antral motility parameters were not different between IBS subtypes.

The epidemiology of irritable bowel syndrome in Denmark. A population-based survey in adults ≤50 years of age

Objective. Our aims were to investigate the prevalence and subtype distribution of irritable bowel syndrome (IBS) according to the Rome III criteria in Denmark, to describe the difference in symptom reporting between those with gastrointestinal (GI) symptoms not fulfilling Rome III for IBS compared to those classified as IBS, and furthermore to describe the proportion of consulters and formally diagnosed subjects. Material and methods. A web-based survey was carried out in January 2010. Questionnaires were emailed to a web panel (n = 19,567) representative of the general Danish population aged 18–50 years on gender, age, and geography. IBS and subtypes were estimated by the Rome III criteria. Results. Of 6112 responders, 979 (16%) fulfilled the Rome III criteria for IBS and had no organic diagnosis likely to explain their symptoms. Subtypes were: mixed IBS 36%, IBS with diarrhea 33%, IBS with constipation 18%, and unsubtyped IBS 11%. Those with GI symptoms, not fulfilling Rome III for IBS, had symptoms very similar to those classified as IBS, but symptoms were less frequent and of shorter duration. Of IBS subjects, 180/978 (18.4%) had consulted a doctor for GI symptoms within the past 3 months, but only 7.9% were diagnosed with IBS. Conclusion.Symptoms compatible with IBS according to Rome III are highly prevalent in Denmark. A high proportion of sufferers are undiagnosed.

Polar vectors as a method for evaluating the effectiveness of irritable bowel syndrome treatments: An analysis with pinaverium bromide 100mg plus simethicone 300mg po bid

Irritable Bowel Syndrome (IBS) is a disorder characterized by abdominal pain or discomfort associated with changes in bowel habit. Currently there are no objective outcome measures for evaluating the effectiveness of treatments for this disorder. To determine the usefulness of a method of analysis that employs polar vectors to evaluate the effectiveness of IBS treatments. Data from a Phase IV clinical study with 1677 active IBS-Rome III patients who received 100mg of pinaverium bromide+300mg of simethicone (PB+S) po bid for a period of four weeks were used for the analysis. Using the Bristol Stool Scale as a reference, the consistency and frequency of each type of bowel movement were recorded weekly in a Bristol Matrix (BM) and the data were expressed as polar vectors. The analysis showed a differential response to the PB+S treatment among the IBS subtypes: in reference to the IBS with constipation subtype, the magnitude of the vector increased from 10.2 to 12.5, reaching maximum improvement at two weeks of treatment (p<0.05, Scheffé). In the IBS with diarrhea and mixed IBS subtypes, the magnitude of the vector decreased from 19 to 14 (p<0.05) and from 16.5 to 13 (p<0.05), respectively, with continuous improvement for a period of four weeks. There was no definable vectorial pattern in the unsubtyped IBS group. Analysis with polar vectors enables treatment response to be measured in different IBS subtypes. All the groups showed improvement with PB+S, but each one had its own characteristic response in relation to vector magnitude and direction. The proposed method can be implemented in clinical studies to evaluate the efficacy of IBS treatments.

PR2 A Feasibility Study of Preference-Based Health-Related Quality of Life Measures on Patients With Irritable Bowel Syndrom in Taiwan

PR2 A FEASIBILITY STUDY OF PREFERENCE-BASED HEALTH-RELATED QUALITY OF LIFE MEASURES ON PATIENTS WITH IRRITABLE BOWEL SYNDROM IN TAIWAN Hsu CC1, Chen LC2, Wen YH1, Su YC3 1Kaohsiung Medical University, Kaohsiung, Taiwan, 2University of Nottingham, UK, 3Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan OBJECTIVES: Irritable bowel syndrome (IBS) is a relapsing, chronic functional gastrointestinal disorder leading to long-term disturbances on health-related quality of life (HRQoL). Various functional and QoL measures have been developed to evaluate IBS outcomes, but none of the preference-based QoL measure has been applied and validated on Taiwanese people. This study aimed to explore the feasibility of applying preference-based HRQoL measures to IBS patients in Taiwan. METHODS: This prospective study was conducted from July to December 2010 at gastroenterology clinics in a regional hospital in southern Taiwan. IBS outpatients diagnosed by Rome III criteria were invited into participate semi-structure interview survey by using EuroQol (EQ-5D) questionnaire, 100-mm visual analogue scale (EQ-5D VAS) and standard gamble (SG) method. The EQ-5D assessment was transformed into EQ-5D index using Japanese preference weight. Multiple regression was used to assess factors associated with utilities, e.g. demographic, socioeconomic status and disease severity. RESULTS: Of all, 29 participants (mean age 45.8 16.5 years; 62.1% female) completed QoL survey, except for one rejected SG survey for disagreeing with SG hypothesis. Participants’ IBS subtypes include constipation (n 11; 37.9%), diarrhea (n 16; 55.2%) and unsubtyped IBS (n 2; 6.9%); and 12 (41.4%) participants were newly diagnosed IBS and 12 had over two-year disease history. Participants had no problem in EQ-5D survey, some expressed difficulties in dimensions of pain/discomfort and anxiety/depression. Mean utility derived from SG (0.85 0.16), EQ-5D index (0.79 0.15) and EQ-5D VAS (0.59 0.17) were significantly different (p 0.05). SG utility was significantly associated with unsubtyped IBS and whether the IBS was newly diagnosed (p 0.05). CONCLUSIONS: IBS is well-tolerated but causing problem in anxiety/depression and pain/discomfort in QoL survey. Mean utility of SG is higher than results derived from EQ-5D and EQ VAS, and this finding matches previous literature. Further validate the utility measures in more IBS patients with various subtypes and severity is needed.

Subtypes and Symptomatology of Irritable Bowel Syndrome in Children and Adolescents: A School-based Survey Using Rome III Criteria

Background/AimsThis study was conducted with objectives of assessing subtypes of irritable bowel syndrome (IBS) in children aged 10-16 years, their symptomatology and gender differences.MethodsFor this survey, 107 children who fulfilled Rome III criteria for IBS and 1,610 healthy controls were recruited from 8 randomly selected schools, in 4 provinces in Sri Lanka. Data was collected using a previously validated, self administered questionnaire.ResultsConstipation predominant, diarrhea predominant and mixed type IBS were almost equally distributed (27%-28%), while unsubtyped IBS had a lower prevalence (17.8%). IBS was more common in girls (59.8% vs 40.2% in boys, P = 0.001). Bloating, flatulence, burping, headache and limb pain were significantly higher in affected children (P < 0.05).ConclusionsThis study highlights the distribution of IBS subtypes among Sri Lankan children and adolescents and its female preponderance. This study also shows a higher prevalence of other intestinal-related and extraintestinal somatic symptoms among affected children.

Subtypes of irritable bowel syndrome on Rome III criteria: A multicenter study

The aim of this study was to explore the distribution and clinical characteristics of four subtypes of irritable bowel syndrome (IBS) based on Rome III criteria in Chinese. A total of 754 consecutive IBS outpatients from three tertiary hospitals in China were included. Diagnostic criteria were based on Rome II or Rome III. Among 754 outpatients, 510 (67.6%) patients met the Rome II criteria, 735 (97.5%) patients met the Rome III criteria and 492 (65.3%) patients met both sets of criteria. Among 735 patients who met the Rome III criteria, 66.3% had IBS with diarrhea (IBS-D), 14.7% had IBS with constipation (IBS-C), 4.2% had mixed IBS (IBS-M) and 14.8% had unsubtyped IBS (IBS-U). Most of the IBS-D, IBS-C and IBS-M patients based on the Rome III criteria matched the diarrhea-predominant IBS, constipation-predominant IBS and alternating IBS based on the Rome II criteria, respectively. Among IBS-U patients, 57.0%, 33.3% and 9.7% had constipation-predominant IBS, diarrhea-predominant IBS and alternating IBS, respectively. For IBS-M, the frequencies of bowel movements were stable in 48.4% patients and variable in 51.6% patients. Defecation urgency and straining were most frequent in IBS-M and least frequent in IBS-U patients than other subtypes. About 77.2% of IBS-U patients had abnormal stool frequency (< 3 times/week or > 3 times/day). The Rome III criteria are more sensitive and practical in diagnosing IBS. IBS-D is the most frequent subtype, which is followed by IBS-U, IBS-C and IBS-M. IBS-U is a new subtype, which warrants further studies.

Prevalence of Irritable Bowel Syndrome: A Community Based Study From Northern India

Background/AimsThe prevalence of irritable bowel syndrome (IBS) varies from 4% to 20% in different Asian nations. Prevalence of IBS in native North Indian community is not known.MethodsBetween November 2008 to December 2009, we estimated the prevalence of IBS in a rural community of Ballabgarh block, located in Haryana state. A structured questionnaire based on Rome III module was used to collect symptoms related to IBS from all the participants in a door to door survey. A Rome III criterion was used for diagnosis of IBS. IBS was further classified based on predominance of symptoms as constipation predominant, diarrhea predominant, mixed and unspecified based on Rome III module.ResultsThere were 4,767 participants (mean age 34.6 ± 10.8, males 50%). Overall, 555 (11.6%; 95% CI, 10.7-12.5) had constipation, 542 (11.4%; 95% CI, 10.5-12.3) diarrhea and 823 (17.3%; 95% CI, 16.2-18.4) abdominal pain. The overall prevalence of IBS was 4% (95% CI, 3.5-4.6). The prevalence of constipation predominant IBS was 0.3% (95% CI, 0.16-0.49), diarrhea predominant IBS 1.5% (95% CI, 1.18-1.90), mixed IBS 1.7% (95% CI, 1.35-2.11) and unsubtyped IBS 0.5% (95% CI, 0.32-0.75). The prevalence of IBS was significantly higher in females compared with males (4.8% vs 3.2%, P = 0.008). However, there was no significant difference between males and females in the prevalence of different subtypes of IBS. The prevalence increased with age.ConclusionsThe prevalence of IBS in a North Indian community is 4%. IBS poses a significant burden on the rural adults.

Differences between risk factors among irritable bowel syndrome subtypes in Japanese adults

Irritable bowel syndrome (IBS) is a common gastrointestinal disease. Detailed clinical characteristics of patients with different IBS subtypes have not been well established. Our aim was to examine the prevalence and risk factors of IBS and its subtypes in Japanese adults. We performed a cross-sectional study of Japanese workers who visited a clinic for a routine health check-up and asked them to fill out a self-report questionnaire. Irritable bowel syndrome and its subtypes were defined by ROME III criteria. A logistic regression model was used to identify risk factors. Irritable bowel syndrome was present in 367 (13.5%) of 2717 eligible subjects; 79 had IBS with constipation (IBS-C); 102 had IBS with diarrhea (IBS-D); 89 had mixed IBS (IBS-M); and 97 had unsubtyped IBS (IBS-U). Irritable bowel syndrome was significantly associated with young age [odds ratio (OR) = 0.87, 95% confidence interval (CI) 0.80-0.95], female gender (OR = 1.78, 95% CI 1.38-2.29), low body mass index (BMI) (OR = 0.95, 95% CI 0.92-0.99), and the presence of allergic disease (OR = 2.19, 95% CI 1.40-3.54). Analysis of IBS subtypes revealed that IBS-C was associated with young age and female gender; IBS-D with young age, low BMI, and drinking habit; IBS-M with female gender, smoking habits, and allergic diseases; and IBS-U with age, female gender, and allergic diseases. Irritable bowel syndrome was common and associated with young age, female gender, low BMI, and presence of allergic diseases in Japanese adults. Several differences were noted between the risk factors among different IBS subtypes.

T1819 The Popcol Study: Epidemiology by Endoscopy in a Swedish Adult Random Population. Intraepithelial Lymphocyte and Eosinophil Counts in the Normal Colon and Irritable Bowel Syndrome

Introduction The normal count for intraepithelial lymphocytes (IELs)/100 enterocytes in the colon has been defined at 20. Normal eosinophil counts are harder to identify. In the caecum, eosinophils are more numerous and up to 40/high power fields (HPF) is suggested to be normal. Irritable Bowel Syndrome (IBS), by definition is not associated with pathology by microscopy but colonic innate immune disorder is implicated in some patients. The aim of this study was to define cell counts in a normal group of subjects and to compare these in subjects with IBS to ascertain if these may be used as biomarkers. Methods Colonoscopy with biopsies was performed in 742 subjects (mean age 51 years, 45% male) and biopsies taken from ileum (TI), caecum, transverse (TC), sigmoid colon (SC) and rectum (R) with a completed validated questionnaire of GI symptoms from a random population sample in Stockholm. Ethical approval, Karolinska Instititet. A case control study was performed comparing 90 normal subjects and 100 subjects with IBS, subtyped,(defined by Rome III criteria) to count IELs/100 enterocytes and eosinophils/5 HPF at each site in biopsies stained by H&E. Sections were examined by two observers. For each section the number of IELs/100 enterocytes was counted, and the number of eosinophils counted in five non-overlapping HPF. Results Of 90 control subjects, mean age 52 years, (SD11.4) 53.3% men. Of 100 IBS patients, mean age 46 years (SD13.7) 39% men. In IBS subjects, 17 were classified IBS-C (35% men), 30 with IBS-D (30% men), 13 with IBS-M (15% men), 40 with unsubtyped IBS (58% men). Lin9s concordance results for inter-observer variability were 0.94 for IELs and 0.99 for eosinophils. Histopathology in controls and IBS was normal. Cell counts were compared in normal subjects categorised by gender, BMI, age and medications and no significant differences were observed between any categories. Eosinophil counts were highest in the caecum regardless of diagnosis (p Conclusion This study has defined normal cell counts for IELs and eosinophils in the TI and colon. No significant differences were found with medication, BMI, age or gender or comparing normal subjects with IBS patients.

PTH-048 The PopCol study: epidemiology by endoscopy in a Swedish adult random population. Intraepithelial lymphocyte and eosinophil counts in the normal colon and irritable bowel syndrome: Abstract PTH-048

<h3>Introduction</h3> The normal count for intraepithelial lymphocytes (IELs)/100 enterocytes in the colon has been defined at 20. Normal eosinophil counts are harder to identify. In the caecum, eosinophils are more numerous and up to 40/high power fields (HPF) is suggested to be normal. Irritable Bowel Syndrome (IBS), by definition is not associated with pathology by microscopy but colonic innate immune disorder is implicated in some patients. The aim of this study was to define cell counts in a normal group of subjects and to compare these in subjects with IBS to ascertain if these may be used as biomarkers. <h3>Methods</h3> Colonoscopy with biopsies was performed in 742 subjects (mean age 51 years, 45% male) and biopsies taken from ileum (TI), caecum, transverse (TC), sigmoid colon (SC) and rectum (R) with a completed validated questionnaire of GI symptoms from a random population sample in Stockholm. Ethical approval, Karolinska Instititet. A case control study was performed comparing 90 normal subjects and 100 subjects with IBS, subtyped,(defined by Rome III criteria) to count IELs/100 enterocytes and eosinophils/5 HPF at each site in biopsies stained by H&amp;E. Sections were examined by two observers. For each section the number of IELs/100 enterocytes was counted, and the number of eosinophils counted in five non-overlapping HPF. <h3>Results</h3> Of 90 control subjects, mean age 52 years, (SD11.4) 53.3% men. Of 100 IBS patients, mean age 46 years (SD13.7) 39% men. In IBS subjects, 17 were classified IBS-C (35% men), 30 with IBS-D (30% men), 13 with IBS-M (15% men), 40 with unsubtyped IBS (58% men). Lin9s concordance results for inter-observer variability were 0.94 for IELs and 0.99 for eosinophils. Histopathology in controls and IBS was normal. Cell counts were compared in normal subjects categorised by gender, BMI, age and medications and no significant differences were observed between any categories. Eosinophil counts were highest in the caecum regardless of diagnosis (p&lt;0.05) (Abstract 048). <h3>Conclusion</h3> This study has defined normal cell counts for IELs and eosinophils in the TI and colon. No significant differences were found with medication, BMI, age or gender or comparing normal subjects with IBS patients.

Subtyping the irritable bowel syndrome by predominant bowel habit: Rome II versus Rome III

The agreement between subtyping irritable bowel syndrome (IBS) patients based on Rome II criteria versus Rome III criteria is unknown. To compare IBS subtyping based on Rome II versus III criteria. The Rome II Modular Questionnaire and the Bristol Stool Form Scale (one-week diary cards) were completed by 249 IBS patients. Based on the Rome II criteria, patients were defined as having diarrhoea- or constipation-predominant IBS, or alternating IBS. Based on the Rome III criteria, patients were divided into IBS with constipation, IBS with diarrhoea, mixed IBS or unsubtyped IBS. Agreement between Rome II and Rome III was assessed with kappa statistics. Based on Rome II there were 92 diarrhoea-predominant IBS, 45 constipation-predominant IBS and 112 alternating IBS, and based on Rome III 97 IBS with diarrhoea, 77 IBS with constipation, 16 mixed IBS and 59 unsubtyped IBS. The agreement between Rome II and Rome III subgroups was 46% (kappa = 0.19). Changes from the constipation to the diarrhoea subgroups and vice versa were uncommon (8% of patients). The majority of changes occurred from/to the alternating IBS, mixed IBS and unsubtyped IBS subgroups. There is poor agreement between subtyping of IBS patients based on Rome II versus Rome III criteria.