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Background and Aims: The group of disorders known as Disorders of Gut Brain Interaction (DGBI) were originally labeled functional GI disorders and were thought to be disorders of the gastrointestinal tract that had several psychological conditions as comorbidities. Despite mounting evidence that psychological morbidity plays an innate role in the etiology and maintenance of DGBI, none of the Rome IV criteria include any measure of psychological symptoms. This study tested the hypothesis that individuals would cluster differently if GI symptoms alone were considered versus GI symptoms combined with measures of psychological symptoms. Methods: Data were obtained from the Rome Foundation Global Epidemiology Study measuring Rome IV GI symptoms, psychological measures and demographic characteristics. Latent profile models were used to cluster individuals based on (i) GI symptoms only (GI only) and then (ii) GI and psychological measures (GI + Psych). Key Results: Individuals clustering into the same group of individuals whether formed via GI only or GI + Psych, ranged from 96% for a 2‐class solution (the most simplistic) to 76% with 6 classes (the parsimonious system) and 59% with twenty‐two classes (mimicking Rome IV). The generalisability of this finding between six geographic regions was confirmed with agreement varying between 95%–97% for 2 clusters and 71–79% for 6 classes and 51%–63% for 22 classes. These findings were also consistent between DGBI (range 94% with 2 classes to 50% with 22 classes) and non‐DGBI (range 97% with 2 clusters to 65% with 22 classes) groups. Conclusions & Inferences: Our data suggest that considering psychological as well as gastrointestinal symptoms would lead to a different clustering of individuals in more complex, and accurate, classification systems. For this reason, future work on DGBI classification should consider inclusion of psychological traits. [ABSTRACT FROM AUTHOR]

Background: Irritable bowel syndrome (IBS) and functional dyspepsia (FD) are common disorders of gut‐brain interaction (DGBI). The Rome IV criteria are the gold standard for research when diagnosing DGBI. However, bothersomeness, or the degree to which symptoms are distressing or disruptive to a person's daily life, is a potential treatment‐seeking motivator that is not assessed by the Rome criteria. The Rome Foundation developed and published diagnostic criteria for clinical practice that include bothersomeness. We aimed to evaluate these constructs via patient focus groups to determine what prompts healthcare‐seeking as a means to assess its value in the Rome clinical criteria. Methods: Adults meeting Rome IV criteria for IBS, FD, or both participated in focus groups in Australia and the United States. Semi‐structured interview transcripts were analyzed using Template Thematic Analysis, with three a priori and other a posteriori themes refined iteratively through team discussion and consensus. Key Results: Participants confirmed the frequency and duration of symptoms was not sufficient to reflect illness experience. Four major themes emerged: (1) Bothersomeness should be included in assessments of IBS and FD; (2) Patients find many DGBI symptoms bothersome; (3) Bothersomeness traverses multiple domains of quality of life; (4) Patients may hesitate to seek medical advice due to past negative experiences. Conclusions and Inferences: These findings support the value of the Rome Clinical Criteria. They emphasize the importance of expanding assessments of patients with DGBI to include how bothersome they perceive symptoms to be, how much symptoms interfere with their daily life, and what may moderate their decisions to seek treatment. [ABSTRACT FROM AUTHOR]

Introduction: Disorders of gut‐brain interaction (DGBI) are symptom‐based disorders categorized by anatomic location but have high overlap and heterogeneity. Viewing DGBI symptoms on a spectrum (i.e. dimensionally) rather than categorically may better inform interventions to accommodate complex clinical presentations. We aimed to evaluate symptom networks to identify how DGBI symptoms interact. Methods: We used the Rome IV Diagnostic Questionnaire continuously/ordinally scored items collected from the Rome Foundation Global Epidemiology Study. We excluded participants who reported ≥1 organic/structural gastrointestinal disorder(s). We sought to (1) identify core symptoms in the DGBI symptom networks, (2) identify bridge pathways between Rome IV diagnostic categories (esophageal, bowel, gastroduodenal, anorectal), and (3) explore how symptoms group together into communities. Results: Of 54,127 adults, 20,229 met criteria for at least one DGBI (age mean = 42.2 ± 15.5; 57% female). General abdominal pain and epigastric pain were the core symptoms in the DGBI symptom network (i.e., had the strongest connections to other symptoms). Pain symptoms emerged as bridge pathways across existing DGBI diagnostic anatomic location (i.e., abdominal pain connected to chest pain, epigastric pain, rectal pain). Without a priori category definitions, exploratory network community analysis showed that symptoms grouped together into "pain," "gastroduodenal," and "constipation," rather than into groups by anatomic location. Conclusion: Our findings suggest pain symptoms are central and serve as a key connection to other symptoms, crosscutting anatomic location. Future longitudinal research is needed to test symptom network relations longitudinally and investigate whether targeting pain symptoms (rather than anatomic‐ or disorder‐specific symptoms) has clinical impact. [ABSTRACT FROM AUTHOR]

Background: Disorders of gut–brain interaction (DGBI) are characterized by debilitating symptoms not explained by structural or biochemical abnormalities. While functional conditions present with complex, likely heterogeneous pathophysiology, we aimed to investigate if proxy measures of sociocultural and environmental factors are associated with the prevalence of various DGBI in populations across the world. Method s : We performed an ecological study utilizing peer‐reviewed published datasets reporting for 26 countries prevalence rates of DGBI (Rome Foundation Global Epidemiology Study, RFGES), with six independent variables: Helicobacter pylori prevalence and household size as proxy measures for orofecal infections, gross domestic product per capita (GDP), and median age as a proxy measures for socioeconomic development, density of fast food outlets (FFO) per 100,000 population as proxy measure for processed food exposure, and suicide mortality rate per 100,000 people, and world happiness scores were used as a proxy for psychological stress. The data were retrieved from publicly accessible datasets (United Nations, CIA World Factbook, World Bank, World Happiness Report, commercial/financial reports of a global FFO chain). We used linear regression to assess variables in univariate and multivariate analysis and report standardized β coefficients with 95% confidence intervals (CI). Key Results: The regression model revealed that the overall prevalence of DGBI was inversely associated with both GDP per capita (β = −0.57, 95% CI: −0.92, −0.22, p = 0.002) and happiness scores (β = −0.433 95% CI: 0.821, −0.065, p = 0.023), while being positively associated with H. pylori prevalence (β = 0.40, 95% CI: 0.008, 0.81, p = 0.046). The prevalence of functional constipation (FC) was also inversely associated with GDP per capita (β = −0.50, 95% CI: −0.86, −0.13, p = 0.01) and happiness scores (β = −0.497, 95% CI: −0.863, −0.132, p = 0.01), while being positively associated with H. pylori prevalence (β = 0.53, 95% CI: 0.16, 0.91, p = 0.007). The Multivariate model analysis revealed that combining the factors of H. pylori prevalence, suicide rate, household size and happiness scores showed statistically significant association with FC (p = 0.039). Household size (β = −0.43, 95% CI: −0.82, 0.038, p = 0.033) and suicide rates (β = 0.55, 95% CI: 0.19, 0.90, p = 0.004) were statistically significantly associated with functional diarrhea. Irritable bowel syndrome (IBS) was associated with GDP per capita (β = −0.40, 95% CI: −0.79, −0.014, p = 0.043) and happiness scores (β = −0.390, 95% CI: −0.778, −0.003, p = 0.049). Conclusions & Inferences: Utilizing publicly available data, the prevalence of DGBI across diverse countries is linked to various socio‐cultural and environmental factors. Collectively, the data suggests that the prevalence of DGBI is increased in less prosperous regions of the world. [ABSTRACT FROM AUTHOR]

Background: Using data from the Rome Foundation Global Epidemiology Study examining prevalence of disorders of gut–brain interaction (DGBI) in 33 countries, this study explored the prevalence of all 22 disorders in Canada. It examined differences related to geography and sociodemographic factors, health impact and compared these findings to other countries. Methods: The Rome Foundation survey was conducted through the Internet, targeting 2000 Canadian participants. The survey used the validated ROME IV diagnostic questionnaire to identify the 22 DGBI and an in‐depth supplemental questionnaire that included quality assurance techniques. Key Results: There were 2029 respondents with a mean age of 48 years and 50% females. Diagnostic criteria for at least one of the 22 DGBI were met by 41.3%, similar to other countries. Functional constipation, functional diarrhea, and unspecified functional bowel disorders were most common. Irritable bowel syndrome prevalence was 4.2% using Rome IV and 10.1% using ROME III criteria. DGBI were associated with poorer quality of life and increased psychological symptom scores. Prevalence of DGBI ranged from 48% in Quebec to 36% in British Columbia. Prescription pain medication was reported by 17% with DGBI compared to 9% without DGBI and correlated negatively with mental health and physical well‐being. Quebecers and francophones were in limited number but reported higher DGBI prevalence and symptom severity compared to others. Conclusions & Inferences: A large proportion of Canadians suffer from DGBI which seriously impact their well‐being. Findings highlight the need for further research and education, including understanding whether significant regional and cultural differences contribute to DGBI. [ABSTRACT FROM AUTHOR]

Background: Data for Spain from the Rome Foundation Global Epidemiology Study on the disorders of gut–brain interaction (DGBI) were used to assess the national and regional prevalence of all 22 DGBI, the percentage of respondents meeting diagnostic criteria for at least one DGBI, and the impact on burden of disease in our country. Methods: Data were collected through an anonymous, nationwide, and secure Internet survey with multiple built‐in quality‐assurance techniques that included the Rome IV diagnostic questionnaire and an in‐depth supplemental questionnaire. Key Results: The survey was completed by 2072 adult Spanish participants (50.2% female) with a mean age of 45.67 ± 15.44 years with a good representative national distribution. 43.6% (41.5%–45.8%) met diagnostic criteria for at least one DGBI, with 8.2% for any esophageal disorder, 12.1% for any gastroduodenal disorder, 30.1% for any bowel disorder, and 11.5% for any anorectal disorder. Functional constipation was the most prevalent DGBI in Spain (12.8%). We found that proctalgia fugax (9.3%), unspecified bowel disorders (10.8%), and functional dysphagia (5.6%) showed unexplained high rates in our country. DGBI rates were higher for women. Having any DGBI was negatively associated with psychosocial variables (including quality of life, somatization, and concern about digestive problems), and associated with increased healthcare utilization. Conclusions & Inferences: We provide the first comprehensive data on the prevalence and burden of all DGBI in Spain using the Rome IV criteria. The enormous burden of DGBI in Spain highlights the need for specialized training and future research. [ABSTRACT FROM AUTHOR]

Background: Although the Rome IV criteria are the most recent criteria to diagnose irritable bowel syndrome (IBS), their sensitivity has been shown to be low in Chinese and Western populations. There are scanty data comparing the Rome III and Rome IV criteria in diagnosis of IBS in the Indian and Bangladeshi populations where abdominal pain, an essential component of diagnosis of IBS by the Rome IV criteria, is less in frequency and of lower severity. Methods: We analyzed the Indian and Bangladeshi data from the Rome Global Epidemiology Study to compare diagnostic sensitivity of the Rome III and Rome IV criteria for IBS, internal shifts in diagnostic categories of disorders of gut–brain interaction (DGBI), the severity of IBS diagnosed by the Rome III and Rome IV criteria, and consultation patterns in these populations. Key Results: The Rome IV criteria were less sensitive than the Rome III criteria to diagnose IBS in these populations, and the subjects with Rome III IBS shifted internally to other DGBI when the Rome IV criteria were applied. Moreover, Rome IV IBS subjects had greater symptom severity than the Rome III IBS. A third of people fulfilling diagnostic criteria for IBS consulted doctors, and those diagnosed using Rome IV criteria, those with higher anxiety and depression symptom score, lower global physical health score, and greater IBS symptom severity score had greater correlation coefficients with doctors' consultation. Conclusions and Inferences: The Rome IV diagnostic criteria for IBS are less sensitive than the Rome III criteria in Indian and Bangladesh communities. Application of the Rome IV criteria to people who meet the Rome III IBS criteria selects a subgroup of people with greater severity of symptoms, and hence, Rome IV IBS is more strongly associated with physician consultation. These findings may have important bearing in future iterations of the Rome criteria for a broader global applicability. [ABSTRACT FROM AUTHOR]

Background: There is no term for bloating in Spanish and distension is a very technical word. "Inflammation"/"swelling" are the most frequently used expressions for bloating/distension in Mexico, and pictograms are more effective than verbal descriptors (VDs) for bloating/distension in general GI and Rome III‐IBS patients. However, their effectiveness in the general population and in subjects with Rome IV‐DGBI is unknown. We analyzed the use of pictograms for assessing bloating/distension in the general population in Mexico. Methods: The Rome Foundation Global Epidemiology Study (RFGES) in Mexico (n = 2001) included questions about the presence of VDs "inflammation"/"swelling" and abdominal distension, their comprehension, and pictograms (normal, bloating, distension, both). We compared the pictograms with the Rome IV question about the frequency of experiencing bloating/distension, and with the VDs. Key Results: "Inflammation"/"swelling" was reported by 51.5% and distension by 23.8% of the entire study population; while 1.2% and 25.3% did not comprehend "Inflammation"/"swelling" or distension, respectively. Subjects without (31.8%) or not comprehending "inflammation"/"swelling"/distension (68.4%) reported bloating/distension by pictograms. Bloating and/or distension by the pictograms were much more frequent in those with DGBI: 38.3% (95%CI: 31.7–44.9) vs. without: 14.5% (12.0–17.0); and in subjects with distension by VDs: 29.4% (25.4–33.3) vs. without: 17.2% (14.9–19.5). Among subjects with bowel disorders, those with IBS reported bloating/distension by pictograms the most (93.8%) and those with functional diarrhea the least (71.4%). Conclusions & Inferences: Pictograms are more effective than VDs for assessing the presence of bloating/distension in Spanish Mexico. Therefore, they should be used to study these symptoms in epidemiological research. [ABSTRACT FROM AUTHOR]

Background: The aim of the study was to assess sex‐ and gender‐related differences in the epidemiology and impact of disorders of gut–brain interaction (DGBI) in Poland. Methods: Data used for the current analysis were derived from the Polish population sample of 2057 subjects (1030 F, 1027 M) collected via the Internet survey that included the Rome IV diagnostic questionnaire and 80 supplementary questions. Key Results: The overall prevalence of DGBI in Poland was 46.0% (51.7% in women and 40.3% in men, p < 0.001). Comparing women versus men, esophageal disorders were observed in 6.3% vs. 6.0%, respectively (p > 0.05), gastroduodenal disorders in 14.0% vs. 7.8% (p < 0.001), bowel disorders in 44.3% vs. 33.9% (p < 0.001), and anorectal disorders in 9.9% vs. 7.7% (p > 0.05). The six most common DGBI included functional constipation 14.2%, functional dyspepsia 8.3%, proctalgia fugax 6.6%, functional bloating 4.8%, functional diarrhea 4.5%, and irritable bowel syndrome (IBS) 4.4%. All these disorders, except for functional diarrhea, were more common in women. The DGBI overlap was significantly higher in women than in men (16.7% vs. 11.2%, p < 0.001). A higher number of overlapping DGBI correlated positively with IBS severity, higher level of somatization, anxiety and depression, poorer quality of life (QoL), and increased healthcare utilization. Conclusions and Inferences: This is the first comprehensive report on significant sex/gender‐related differences in the prevalence and burden of DGBI in Poland. The revealed differences between women and men with DGBI in the clinical profile, psychosocial variables, and healthcare utilization may have important diagnostic and therapeutic implications. [ABSTRACT FROM AUTHOR]

Objective: Many studies have been published on disorders of the gut–brain interaction (DGBI) in Asia and Western Europe, but no previous study has directly assessed the difference between the two regions. The aim was to compare the prevalence of DGBI in Asia and Western Europe. Methods: We used data collected in a population‐based Internet survey, the Rome Foundation Global Epidemiology Study, from countries in Western Europe (Belgium, France, Germany, Netherlands, Italy, Spain, Sweden, and the United Kingdom) and Asia (China, Japan, South Korea, and Singapore). We assessed DGBI diagnoses (Rome IV Adult Diagnostic Questionnaire), anxiety/depression (Patient Health Questionnaire‐4, PHQ‐4), non‐GI somatic symptoms (PHQ‐12), and access to and personal costs of doctor visits. Results: The study included 9487 subjects in Asia and 16,314 in Western Europe. Overall, 38.0% had at least one DGBI; younger age, female sex, and higher scores on PHQ4 and PHQ12 were all associated with DGBI. The prevalence of having at least one DGBI was higher in Western Europe than in Asia (39.1% vs 36.1%, OR 1.14 [95% CI 1.08–1.20]). This difference was also observed for DGBI by anatomical regions, most prominently esophageal DGBI (OR 1.67 [1.48–1.88]). After adjustment, the difference in DGBI prevalence diminished and psychological (PHQ‐4) and non‐GI somatic symptoms (PHQ‐12) had the greatest effect on the odds ratio estimates. Conclusion: The prevalence of DGBI is generally higher in Western Europe compared to Asia. A considerable portion of the observed difference in prevalence rates seems to be explained by more severe psychological and non‐GI somatic symptoms in Western Europe. [ABSTRACT FROM AUTHOR]

Background: Methodological problems have impeded successful epidemiological research into disorders of gut‐brain interactions (DGBI), as previous studies were limited in terms of study population, diagnostic criteria, number of disorders assessed, data collection methods, and geographic area. Most prevalence estimates were based on pooling data from heterogeneous studies using inappropriate pooling methods, seriously limiting the relevance of the results. The Rome Foundatiion Global Epidemiology Study (RFGES) aimed to rectify these limitations using rigorous methodology to survey the prevalence of 22 DGBI in large population samples in 33 countries. Its aims were to conduct a comprehensive, multinational epidemiological study using rigorous research methodology, gain a better understanding of the burden of the DGBI, gain reliable regional estimates of DGBI prevalence, and advance our understanding of the pathophysiology of IBS. The study questionnaire consisted of the 89‐item Rome IV Adult Diagnostic Questionnaire enabling the diagnosis of 22 DGBI, and an 80‐item supplemental questionnaire that enabled analyses of the association of multiple factors with DGBI diagnoses. Purpose for review article: This review paper introduces a special issue on the Rome Foundation Global Epidemiology study (RFGES) with a narrative description of its conception, development, and implementation, its outcomes to date, and its potential contribution to neurogastroenterology. It includes 15 papers that reflect the range of RFGES studies from single country papers to intra‐regional studies, to inter‐regional studies, and one global study. [ABSTRACT FROM AUTHOR]

Background: No comprehensive assessment of disorders of gut‐brain interaction (DGBI) in the United States (US) national population has been published in the past three decades. We aimed to provide an updated picture of DGBI in the United States and associated factors, using data from two national Internet surveys. Methods: Data were analyzed from 1949 people surveyed in 2015, and 2023 people surveyed in 2017 as a part of the Rome Foundation Global Epidemiology Study (RFGES). The surveys had nearly identical methodology and included the Rome IV Diagnostic Questionnaire and questions on demographics, quality of life (QoL), emotional symptoms, and healthcare utilization. Key Results: The prevalence of having any DGBI was 36.0% and 39.9% in the two surveys. Prevalence estimates for the 22 DGBI assessed were broadly comparable between the surveys, as their 95% confidence intervals overlapped for every disorder. Females had DGBI more commonly than males in both surveys (odds ratios 1.66 and 1.52), and people of age 65 and older had lower DGBI prevalence than younger age groups. Having DGBI was associated in both surveys with significant QoL impairment, elevated anxiety, depression and somatization symptoms, and increased doctor visits. Conclusions and Inferences: Approximately 4 out of every 10 US adults have a DGBI; more commonly women and people under the age of 65. DGBI adversely affect QoL and emotional well‐being and increase healthcare needs. The similarity of findings between the two surveys supports the reliability of DGBI prevalence estimates obtained with the Internet survey method used globally in the RFGES. [ABSTRACT FROM AUTHOR]

Background: Forty percent of individuals globally meet Rome IV criteria for a disorder of gut–brain interaction (DGBI). The global burden of pain across these disorders has not been characterized. Methods: Our study included 54,127 respondents from the 26 Internet survey countries. Prescription pain medication usage was selected as the proxy for pain. The associations between prescription pain medications and the environmental, sociodemographic, psychosocial, and DGBI diagnosis variables were investigated using the multivariate generalized robust Poisson regression model. Key Results: Respondents with DGBI used prescription pain medications at higher rates than those without a DGBI diagnosis with pooled prevalence rate of 14.8% (95% confidence interval [CI], 14.4–15.3%), varying by country from 6.8% to 25.7%. The pooled prevalence ratio of prescription pain medication usage in respondents with and without DGBI was 2.2 (95% CI: 2.1–2.4). Factors associated with higher prevalence of pain medication usage among respondents with a DGBI diagnosis included living in a small community, increased anxiety, depression or somatization, increased stress concern or embarrassment about bowel functioning and having more than one anatomic DGBI diagnosis. Conclusion: 14.8% of patients globally with at least one diagnosis of DGBI were on prescription pain medications with wide geographic variation, about twice as many as their counterparts without a diagnosis of DGBI. Environmental, sociodemographic, and individual factors may influence clinicians to consider personalized, multimodal approaches to address pain in patients with DGBI. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Methods Key Results Conclusions and Inferences Disorders of gut–brain interaction (DGBI) predominate in women, but little is known about sex differences in menses‐related or menopause symptoms.Using data from the Rome Foundation Global Epidemiology Survey, we assessed Rome IV DGBI symptoms in individuals in 26 countries who met criteria for ≥ 1 of 5 DGBI: irritable bowel syndrome (IBS), functional dyspepsia (FD), functional constipation (FC), functional diarrhea (FDr), or functional bloating (FB). Participants included pre‐ and post‐menopausal women with DGBI and age‐matched men. Odds ratios estimated sex and age differences for symptom by sex or pre‐ vs. post‐menopause in logistic regression; standardized mean difference (SMD) provided effect sizes.14,570 participants met criteria for ≥ 1 of the 5 DGBI. Women exceeded men in most symptoms. In FD, women stopped eating due to early satiety more than men (11.1 vs. 8.9 days/month, SMD 0.21). Symptoms were generally increased in premenopausal women and younger men compared to older counterparts; however, only premenopausal IBS, FD, and FC women reported increased constipation‐associated symptoms. Compared to premenopausal women, postmenopausal women had increased accidental stool leakage in IBS and FDr, and increased digital manual maneuvers in FC (18% vs. 25% frequency, SMD −0.25). IBS and FD had the most menses‐associated symptoms.Women had higher symptom frequency across the 5 DGBI compared to men. Our findings suggest that premenopausal women have greater visceral perception than postmenopausal women, although increased outlet symptoms in postmenopausal women indicate greater anorectal/pelvic dysfunction. While age alone has some influence on symptoms, female sex hormones may also increase visceral perception. [ABSTRACT FROM AUTHOR]

Background: In a previous clinical sample of IBS patients, subgroups characterized by profiles of GI and non‐GI symptoms were identified. We aimed to replicate these subgroups and symptom associations in participants fulfilling IBS diagnostic criteria from a population‐based study and relate them to healthcare utilization. Methods: An Internet‐based health survey was completed by general population adults from United States, Canada, and UK. Respondents fulfilling IBS diagnosis (Rome III and IV) were analyzed for latent subgroups using Gaussian mixture model analysis. Symptom measures were derived from validated questionnaires: IBS‐related GI symptoms (Rome IV), extraintestinal somatic symptoms (PHQ‐12), and psychological symptoms (SF‐8). Key Results: A total of 637 respondents fulfilled Rome III criteria (average age 46 years, range 18‐87, 66% females) and 341 Rome IV criteria (average age 44, range 18‐77, 64% female) for IBS. Seven subgroups were identified in the Rome III cohort, characterized by profiles of GI symptoms (constipation‐related, diarrhea‐related, and mixed, respectively), and further distinguished by the presence or absence of non‐GI comorbidities. The Rome IV cohort showed five similar but less distinct subgroups with a preponderance of mixed symptom profiles. Higher severity of non‐GI comorbidities was associated with more frequent healthcare visits and medication usage. Conclusions and Inferences: In line with previous findings in a clinical IBS cohort, we were able to identify population‐based subgroups characterized by a combination of GI symptoms with the additional distinction made by varying severity of non‐GI symptoms and with differences in healthcare utilization. IBS is a heterogeneous disorder. In a clinical sample of IBS patients (Rome III), subgroups defined by specific profiles of GI and non‐GI symptom severity were previously identified. We aimed to replicate these subgroups in a population‐based study. In participants fulfilling Rome III and Rome IV diagnostic criteria for IBS, the subgroups based on a combination of GI and non‐GI symptom profiles could largely be replicated. Groups with more severe non‐GI symptoms reported higher healthcare utilization. This subgrouping approach could facilitate the identification of individual treatment needs and predict healthcare consumption in IBS. [ABSTRACT FROM AUTHOR]