Irritable Bowel Syndrome Subtypes Research Articles

A Randomized Parallel-group Study of Digital Gut-directed Hypnotherapy vs Muscle Relaxation for Irritable Bowel Syndrome

Gut-directed hypnotherapy (GDH) is effective for treating irritable bowel syndrome (IBS), but access limits its widespread use. We report the first randomized controlled trial comparing the safety and efficacy of a self-administered, digital GDH treatment program with that of digital muscle relaxation (MR) in adults with IBS. After a 4-week run-in period, patients were randomized to 12 weeks of treatment with digital GDH (Regulora), or digital MR accessed via a mobile app on a smartphone or tablet. The primary endpoint was abdominal pain response, defined as ≥30% reduction from baseline in average daily abdominal pain intensity in the 4 weeks following treatment. Key secondary outcomes included mean change from baseline in abdominal pain, stool consistency, and stool frequency. Of 378 randomized patients, 362 were treated and included in the efficacy analysis. A similar proportion of the GDH (30.4%) and MR (27.1%) groups met the primary endpoint, with no significant difference between the groups (P= .5352). Significantly more patients treated with GDH than MR were abdominal pain responders during the last 4 weeks of treatment (30.9% vs 21.5%; P= .0232) and over the entire treatment period (29.3% vs 18.8%; P= .0254). Improvements in abdominal pain, stool consistency, and stool frequency were consistent across IBS subtypes. No patients experienced serious adverse events or adverse events leading to study discontinuation. Treatment with a digital GDH program led to an improvement in abdominal pain and stool symptoms in patients with IBS, supporting a role for this intervention as part of integrated care for IBS. gov identifier NCT04133519.

Dietary intake of phytochemicals in association with irritable bowel syndrome in adults

There is limited data regarding the association between phytochemical-rich diets and irritable bowel syndrome (IBS). The current study aimed to cross-sectionally evaluate the association of dietary phytochemical index (DPI) with the odds and severity of IBS. In this study, which included 3362 Iranian healthcare staffs, a dish-based semi-quantitative food frequency questionnaire (DS-FFQ) was utilized to collect dietary information. The DPI was defined as the daily percentage of calories consumed from phytochemical-rich foods. The IBS assessment was performed using a revised Iranian version of the Rome III questionnaire. We applied the restricted cubic spline (RCS) to detect the possible non-linear dependency of the relationship between DPI and the odds of IBS. The mean age, Body Mass Index (BMI), and DPI scores of the participants were 36.29±7.8 years, 24.90±3.8kg/m2, and 16.07±9.01, respectively. After adjusting for possible confounders, no significant association was observed between DPI and odds of IBS in the whole study population or in gender- and BMI-stratified analyses. We found a significant inverse association between DPI and IBS severity in the study population (OR: 0.70; 95% CI: 0.51-0.98). Concerning gender, such an association was only found in women (OR: 0.65; 95% CI: 0.44-0.96). However, there was no significant relationship between DPI and IBS severity in BMI subgroups. In addition, we found no meaningful relationship between DPI and IBS subtypes. The RCS model showed that there is no non-linear relationship between DPI classification and IBS (non-linear test, χ2=1.14, Pnon-linearity=0.513). Higher phytochemical intake was associated with reduced IBS severity, particularly in women. Further prospective studies are required to confirm these findings.

150 risk variants for diverticular disease of intestine prioritize cell types and enable polygenic prediction of disease susceptibility

We conducted a genome-wide association study (GWAS) analysis of diverticular disease (DivD) of intestine within 724,372 individuals and identified 150 independent genome-wide significant DNA variants. Integration of the GWAS results with human gut single-cell RNA sequencing data implicated gut myocyte, mesothelial and stromal cells, and enteric neurons and glia in DivD development. Ninety-five genes were prioritized based on multiple lines of evidence, including SLC9A3, a drug target gene of tenapanor used for the treatment of the constipation subtype of irritable bowel syndrome. A DivD polygenic score (PGS) enables effective risk prediction (area under the curve [AUC], 0.688; 95% confidence interval [CI], 0.645-0.732) and the top 20% PGS was associated with ∼3.6-fold increased DivD risk relative to the remaining population. Our statistical and bioinformatic analyses suggest that the mechanism of DivD is through colon structure, gut motility, gastrointestinal mucus, and ionic homeostasis. Our analyses reinforce the link between gastrointestinal disorders and the enteric nervous system through genetics.

Disordered eating and eating competence in members of online irritable bowel syndrome support groups.

This study seeks to evaluate eating competence and disordered eating likelihood among members of online support groups for irritable bowel syndrome (IBS) and determine whether eating competence and disordered eating likelihood varies according to IBS symptom severity and subtype. This cross-sectional study is based on an anonymous survey conducted from August to September 2021. Adults with IBS (N = 225) were recruited from online and social media IBS support forums. IBS symptom severity was assessed using the validated IBS Severity Scoring System (IBS-SSS), likelihood of disordered eating was assessed using the validated Eating Attitudes Test (EAT-26), and eating competence was assessed using the validated Satter Eating Competence Inventory (ecSI 2.0™). Multiple linear regression was used to predict EAT-26 total score from IBS-SSS score, age, and IBS subtype. ANOVAs were used to examine the relationships between IBS severity level, IBS subtype, and ecSI 2.0™ total score. Eating competence among the sample was low at 17% while 27% was classified as likely or very likely disordered eating. IBS severity was positively associated with EAT-26 score (p = 0.011) and ecSI 2.0™ score was significantly lower in the severe IBS group compared to the moderate IBS group (p = 0.016). No relationship was detected between IBS subtype and EAT-26 or ecSI 2.0™ scores. IBS severity was positively associated with disordered eating likelihood and negatively associated with eating competence. This sheds light on the importance of assessing eating competence and screening for disordered eating prior to selecting therapies for patients with IBS, particularly in females with severe symptoms.

The impact of diet and ethnicity on gut microbiota variation in irritable bowel syndrome: A multi-center study.

The gut microbiota in irritable bowel syndrome (IBS) is known to vary with diet. We aim to (i) analyze the gut microbiota composition of IBS patients from a multi-ethnic population and (ii) explore the impact of a low FODMAP diet on gastrointestinal symptoms and gut microbiota composition among IBS patients. A multi-center study of multi-ethnic Asian patients with IBS was conducted in two phases: (i) an initial cross-sectional gut microbiota composition study of IBS patients and healthy controls, followed by (ii) a single-arm 6-week dietary interventional study of the IBS patients alone, exploring clinical and gut microbiota changes. A total of 34 adult IBS patients (IBS sub-types of IBS-D 44.1%, IBS-C 32.4%, and IBS-M 23.5%) and 15 healthy controls were recruited. A greater abundance of Parabacteroides species with lower levels of bacterial fermenters and short-chain fatty acids producers were found among IBS patients compared with healthy controls. Age and ethnicity were found to be associated with gut microbiota composition. Following a low FODMAP dietary intervention, symptom and quality of life improvement were observed in 24 (70.6%) IBS patients. Symptom improvement was associated with adherence to the low FODMAP diet (46.7% poor adherence vs 92.9% good adherence, P=0.014), and gut microbiota patterns, particularly with a greater abundance of Bifidobacterium longum, Anaerotignum propionicum, and Blautia species post-intervention. Gut microbiota variation in multi-ethnic IBS patients may be related to dietary intake and may be helpful to identify patients who are likely to respond to a low FODMAP diet.

Irritable bowel syndrome – modern ways of treatment

Introduction
 Irritable bowel syndrome (IBS) is the most frequent functional disorder of the gastrointestinal tract. Main symptoms are recurring stomach ache connected with defecation, changes of frequency of defecation and/or stool’s consistency. Cause of IBS is still unknown unlike its pathomechanism. Continuous research allows doctors to understand and treat it better.
 Discussion
 Diagnosing IBS might be difficult even for the most experienced doctors due to its uncharacteristic symptoms. Therefore diagnosis should be made by using Rome IV Criteria. IBS is divided into 4 subtypes basing on clinical picture: IBS with predominant constipation, IBS with predominant diarrhea, IBS with mixed bowel habits and IBS unclassified. Classification is being performed with the use of Bristol Stool Chart. Choice of remedy should be made depending on the subtype of IBS. Pharmacological treatment is symptomatic and focuses on relieving pain, diarrhea, constipation and bloating. Drugs that can be used are: loperamide, rifaximin, antispasmodic (e.g. hyoscine), antidepressants or laxatives. Treatment should also contain nonpharmacological methods. Nonpharmacological techniques which are proved to help patients contain regular physical activity, body mass reduction, low-FODMAP diet, using probiotics, psychotherapy and supplementing soluble fibre.
 Conclusions
 IBS is a big issue for public health as it is lowering quality of life and is generating big indirect costs. Difficulties in diagnosing are increasing those costs. That’s why it is of high importance to find more effective therapy. Raising awareness among doctors is crucial as plenty of methods are available to treat the disease which allows to reduce symptoms and costs.

Procedures in Fecal Microbiota Transplantation for Treating Irritable Bowel Syndrome: Systematic Review and Meta-Analysis.

Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disease with no effective treatment. Altered microbiota composition seems implicated in disease etiology and therefore fecal microbial transplantation (FMT) has emerged as a possible treatment therapy. To clarify the clinical parameters impacting FMT efficacy, we conducted a systematic review with subgroup analysis. A literature search was performed identifying randomized controlled trials (RCTs) comparing FMT with placebo in IBS adult patients (8-week follow-up) with a reported improvement in global IBS symptoms. Seven RCTs (489 participants) met the eligibility requirements. Although FMT seems not to be effective in global improvement of IBS symptoms, subgroup analysis shows that FMT through gastroscopy or nasojejunal tube are effective IBS treatments (RR 3.03; 95% CI 1.94-4.73; I2 = 10%, p < 0.00001). When considering non-oral ingestion routes, IBS patients with constipation symptoms are more likely to benefit from FMT administration (p = 0.003 for the difference between IBS subtypes regarding constipation). Fresh fecal transplant and bowel preparation seem also to have impact on FMT efficacy (p = 0.03 and p = 0.01, respectively). Our meta-analysis revealed a set of critical steps that could affect the efficacy of FMT as clinical procedure to treat IBS, nevertheless more RCTs are needed.

Hipertansiyonlu İrritabl Barsak Sendromlu Hastalarda Klinik Alt Tipler Arasında Kan Basıncı Değişkenliğinin Karşılaştırılması

Objective: In this study, we aimed to compare blood pressure variability among irritable bowel syndrome subtypes. Methods: Patients with newly diagnosed irritable bowel syndrome and existing hypertension were included in the study. Average real variability (ARV) was calculated by consecutive one week home blood pressure measurements. Groups were compared for blood pressure variability. Results: While diastolic ARV was found to be similar among subtypes (p=0.919), a significant difference was found between them in terms of systolic ARV (p&amp;lt;0.001). Conclusion: Since irritable bowel syndrome patients with constipation-predominant subtype have higher systolic blood pressure variability, these patients can be followed more closely for cardiovascular complications.

The Socioeconomic Impact of Irritable Bowel Syndrome: An Analysis of Direct and Indirect Health Care Costs

Irritable bowel syndrome (IBS) is associated with substantial costs to society. Extensive data on direct costs (health care consumption) and indirect costs (health-related productivity loss) are lacking. Hence, we examined the socioeconomic costs of IBS and assessed which patient characteristics are associated with higher costs. Cross-sectional data from 3 Rome-defined Dutch IBS patient cohorts (n= 419) were collected. Bootstrapped mean direct and indirect costs were evaluated per patient with IBS using validated questionnaires (ie, medical cost questionnaire and productivity cost questionnaire, respectively). Multivariable regression analyses were performed to identify variables associated with higher costs. Quarterly mean total costs per patient were €2.156 (95% confidence interval (CI), €1793-€2541 [$2444]), consisting of €802 (95% CI, €625-€1010 [$909]) direct costs and €1.354 (95% CI, €1072-€1670 [$1535]) indirect costs. Direct costs consisted primarily of health care professional consultations, with costs related to gastrointestinal clinic visits accounting for 6% and costs related to mental health care visits for 20%. Higher direct costs were significantly associated with older age (P= .007), unemployment (P= .001), IBS subtypes other than constipation (P= .033), lower disease-specific quality of life (P= .027), and more severe depressive symptoms (P= .001). Indirect costs consisted of absenteeism (45%), presenteeism (42%), and productivity loss related to unpaid labor (13%) and were significantly associated with the male sex (P= .014) and more severe depressive symptoms (P= .047). Productivity loss is the main contributor to the socioeconomic burden of IBS. Direct costs were not predominantly related to gastrointestinal care, but rather to mental health care. Awareness of the nature of costs and contributing patient factors should lead to significant socioeconomic benefits for society.

Identification of irritable bowel syndrome in the Swedish National Patient Register: a validation study

Background and objective National patient registers are valuable in epidemiological studies. To ensure high-quality data for studies of irritable bowel syndrome (IBS), this study aimed to validate the ICD-10 code for IBS in the Swedish National Patient Register. Methods The positive predictive values (PPV) for IBS defined by the Rome criteria were calculated based on a review of medical records of randomly selected individuals with a first-ever diagnostic listing of IBS in the Swedish National Patient register in the year 2005 (Rome II criteria) or 2010 (Rome III criteria). Key results 340 medical records were reviewed (172 from 2005 and 168 from 2010). The majority of patients were females (74%), and the mean age was 42 years. IBS used in any type of department had a PPV of 76% (95% confidence interval 71–80%), which increased to 80% (76–84%) when we included individuals likely to have IBS but where information about some aspects of the Rome criteria was lacking in the medical record. Two highly specialized gastroenterological departments had the best PPV, 96%, while departments of internal medicine in general had a PPV of 82% (80–95%). The PPV for the IBS subtype was 62% (55–67%). The PPVs were not significantly different comparing the two time periods investigated. Conclusion and inferences The validity of a register-based definition of IBS in the Swedish National Patient register is high and can be used to identify patients with IBS in observational research. The data source, i.e., type of hospital and department, influences reliability.

Positive psychological well-being: A novel concept for improving symptoms, quality of life, and health behaviors in irritable bowel syndrome.

Though a growing body of research suggests that greater positive psychological well-being in irritable bowel syndrome (IBS) may be protective, existing brain-gut behavior therapies primarily target negative psychological factors. Little is known about how positive psychological factors in IBS relate to IBS symptoms, health-related quality of life (HRQoL), or adherence to key health behaviors, such as physical activity and diet modification. Accordingly, per the ORBIT model of behavioral treatment development for chronic diseases, we explored potential connections between psychological constructs and IBS symptoms, health behavior engagement (physical activity and dietary modification), and HRQoL in a qualitative study to inform the development of a novel brain-gut behavior therapy. Participants with IBS completed self-report assessments and semi-structured phone interviews about relationships between positive and negative psychological constructs, IBS symptoms, health behavior engagement, and HRQoL. Participants (n=23; 57% female) ranged in age from 25 to 79 (mean age=54). IBS subtypes were similarly represented (IBS-diarrhea [n=8], IBS-constipation [n=7], and IBS-mixed [n=8]). Participants described opposing relationships between positive and negative psychological constructs, IBS symptoms, health behavior engagement, and HRQoL, respectively, such that experiencing positive constructs largely mitigated IBS symptoms, boosted health behavior participation, and improved HRQoL, and negative constructs exacerbated symptoms, reduced health behavior participation, and worsened HRQoL. Participants with IBS linked greater positive psychological well-being to moderated IBS symptoms and better HRQoL and health behavior participation. An intervention to cultivate greater well-being may be a novel way to mitigate IBS symptoms, boost health behavior participation, and improve HRQoL in IBS.

Burden of anxiety and depression among hospitalized patients with irritable bowel syndrome: a nationwide analysis.

Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder that affects patients both physically and mentally. Our study aimed to investigate the burden of psychiatric disorders in IBS patients. We conducted a retrospective analysis of the National inpatient sample (NIS) from 2016 to 2019. We recruited patients admitted with a diagnosis of IBS and determined the prevalence of anxiety, depression, and suicide attempt/ideation. We found a total of 1,256,325 hospitalizations with a diagnosis of IBS. Among them, 478,515 (38.1%) had anxiety and 344,165 (27.4%) had depression. The prevalence of psychiatric disorders including anxiety (38.1% vs. 15.1%), depression (38.1% vs. 15.1%), bipolar disorder (5.22% vs. 2.38%), suicidal attempt/Ideation (3.22% vs. 2.38%), and eating disorder (0.32% vs. 0.08%) was significantly higher in IBS patient population when compared to general adult population (p < 0.001). Patients with IBS had greater odds of anxiety (AOR 2.88, 95% CI 2.85-2.91, P < 0.001), depression (AOR 2.16, 95% CI 2.14-2.19, P < 0.001) and suicidal attempt/ideation (AOR 1.94, 95% CI 1.88-2.00, P < 0.001) in comparison to general population. IBS subtypes including diarrhea-predominant, constipation-predominant and mixed type were independently associated with increased odds of anxiety, depression, and suicide attempt/ideation. Patients with IBS and a co-diagnosis of anxiety or depression had increased mean length of hospital stay by 0.48 (95% CI 0.43-0.52, P < 0.001) and 0.52 (95% CI 0.06-0.97, P < 0.03) days, respectively. The presence of IBS is associated with an increased associated prevalence of psychiatric disorders such as anxiety, depression, and suicide attempt/ideation.

The incidence of adult type hypolactasia in patients with irritable bowel syndrome

The incidence of lactose intolerance in irritable bowel syndrome (IBS) varies in the literature (27-72%). Primary adult lactase deficiency (adult type hypolactasia) is the most common type of primary enzyme deficiency. Complaints related to lactose intolerance may overlap with the symptoms of IBS. To assess the prevalence of primary hypolactasia in patients with IBS. The study included 56 patients with IBS diagnosed based on the Rome III criteria and 23 healthy people. All study participants completed a questionnaire on IBS symptoms and lactose intolerance, and they underwent a hydrogen breath test (HBT) with lactose. In the group of patients with positive results of HBT, the polymorphism C/T -13910 and G/A -22018 in the promoter of the LCT gene encoding lactase was determined. Lactase deficiency was diagnosed in HBT in 34 (60.7%) patients with IBS and in the control group - in 10 (43.5%). Primary adult type hypolactasia was confirmed in 78.9% (n = 30; 79.3% in the study group; 77.8% in the control group). There were no statistically significant differences in the occurrence of LCT gene polymorphisms in particular IBS subtypes. Adult type hypolactasia was significantly more common in patients with severe than moderate and mild enzyme deficiency in HBT (p < 0.05). The incidence of lactase deficiency in IBS patients is not different from that found in healthy subjects. Nevertheless, irrespective of the IBS subtype, lactose intolerance may pose additional issues in patients with IBS and requires the targeted treatment.

Gut microbiome signatures reflect different subtypes of irritable bowel syndrome

ABSTRACT Irritable bowel syndrome (IBS) is a heterogeneous condition with multifactorial pathogenesis. We studied deeply phenotyped individuals with microbiota sequencing enrolled in the American Gut Project. The IBS subjects were matched by age, gender, body mass index, geography, and dietary patterns with non-IBS controls. A total of 942 subjects with IBS-Diarrhea (IBS-D), IBS-Constipation (IBS-C), unclassified IBS (IBS-U), and 942 non-IBS controls were included. We compared taxonomic and functional composition of gut microbiota based on 16S sequencing data and linked them with clinical characteristics and dietary factors. Subjects with IBS-D or IBS-U but not IBS-C showed significantly reduced bacterial diversity (Shannon; p < .01). Distinct bacterial signatures were associated with different IBS subtypes, and the related functional changes were related to IBS pathogenesis, such as the increased hydrogen sulfide production pathway in IBS-D and the increased palmitoleate biosynthesis pathway in IBS-C. IBS subjects with depression showed lower abundance of Bifidobacterium, Sutterella, Butyricimonas and higher abundance of Proteus than those without depression. The relative abundance of microbial short-chain fatty acid production pathways was significantly lower in IBS patients with depression than those without depression in all three subtypes. Female, younger age in IBS-D, and older age in IBS-C were associated with more severe microbiota dysbiosis, and distinct dietary factors had significant effects on the gut microbiota in different IBS subtypes. Our analysis identified the compositional uniqueness of gut microbiota in different IBS subtypes. Distinct associations of the gut microbiota with depression in IBS provide insights into shared pathways in disease pathogenesis. These findings highlight the importance of personalized gut microbiome modulation approaches in different subtypes for optimal therapeutic effects.

Factors influencing rectal hypersensitivity in irritable bowel syndrome: A systematic review and meta-analysis.

A frequent, although not universal, feature of irritable bowel syndrome (IBS) is heightened sensitivity to mechanical stimulation of the rectum, termed rectal hypersensitivity (RH). Differences in RH-based on sex, IBS subtype, IBS diagnostic criteria and age of population studied are incompletely understood. We aimed to determine whether IBS population had lower pain thresholds than healthy controls. We searched MEDLINE and EMBASE databases (1970-2021). Prospective studies that compared pain/discomfort thresholds to mechanical rectal stimuli in IBS and healthy controls were included. Data were pooled for meta-analyses and effect sizes were calculated with 95% confidence interval (CIs). Our search strategy identified 809 studies of which 32 studies met the inclusion criteria. Reduced rectal pain thresholds was more common in IBS patients compared to healthy controls with an effect size of 1.00 95% CIs (0.77-1.24) (p< 0.0001) (I2 = 78.6%). The pediatric IBS population had lower pain thresholds than adult IBS populations (p= 0.05) but no difference based on IBS diagnostic criteria, subtype or sex. The results suggest that reduced rectal pain threshold to experimental stimulation is far more common in IBS patients than healthy controls. Further research is required to understand the pathophysiological and therapeutic implications of rectal sensitivity such as its role in measuring response to treatment and prognosis in IBS.

The Prevalence of Irritable Bowel Syndrome and Its Relation to Psychiatric Disorders Among Citizens of Makkah Region, Saudi Arabia.

Irritable bowel syndrome (IBS) is a chronic functional bowel disorder. Many adults worldwide have symptoms associated with IBS and are responsible for most gastroenterology visits. The aim of this study is to illustrate and analyze the prevalence of IBS among the general population in Makkah Al-Mukarramah city using the Rome IV criteria in relation to psychiatric disorders. This was a cross-sectional study conducted on Makkah citizens. The study excluded all residents in Makkah without Saudi nationality or below the age of 18. The survey was created using Google forms and shared randomly on social media. The sample size was calculated using the OpenEpi website v3.0. The online questionnaire is composed of three sections: sociodemographic data, Rome IV criteria with the Bristol Stool Scale, and lastly the Depression, Anxiety, and Stress Scale 21 (DASS-21) score for stress, anxiety, and depression. Data were analyzed using SPSS software for Windows V.23, and odds ratio (OR) with 95%confidence intervals (95% CI) was obtained for selected risk factors using logistic regression. Nine hundred and twenty-one individuals from Makkah city completed the survey. The overall IBS prevalence was 20.19%. The commonest subtypes of IBS were IBS-M followed by IBS-C (53.8% and 22%, respectively). In the multiple regression analysis, stress (P = <0.001, OR = 2.473) was statistically significantly associated with IBS. In this study, the prevalence of IBS among Makkah citizens is high. Stress was found to be a major risk factor for IBS.

Non-pharmacological strategies to treat irritable bowel syndrome: 2022 update.

Irritable bowel syndrome (IBS) is a chronic functional disorder characterized by abdominal pain associated with changes in stool frequency or form, in absence of organic disease. The treatment of IBS is often challenging and should be individually adjusted according to the prevalent symptomatology. Pharmacological treatment for IBS with diarrhea includes peripheral opioid agonists, bile acid sequestrants and antibiotics, while IBS with constipation can be treated with soluble fibers, osmotic agents or prokinetics. In case of abdominal pain, the available pharmacological options are antispasmodics, peripheral opioid agonists or antidepressants. Along with pharmacotherapy, non-pharmacological interventions should be considered as they can play an important role in symptom control. The first-line approach includes lifestyle modifications and dietary advice. Microbiota manipulation through probiotics, prebiotics and symbiotics is a widely used strategy, although the evidence upon the most effective among these in specific IBS subtypes is still unclear. Fecal microbiota transplantation is still in experimental phase for IBS, but it is giving promising results. Psychological therapies may be effective in patients with IBS, despite their application can be limited by long duration, high costs and poor patient's acceptance. Alternative medicine approaches, such as acupuncture, body relaxation techniques, dietary supplements or Chinese herbs, have been proposed; however, the evidence upon their efficacy and safety is still controversial.

The association between dietary acid load and odds and severity of irritable bowel syndrome in adults

No study has been conducted to investigate the association between dietary acid load and irritable bowel syndrome (IBS). So, this cross-sectional study was performed to investigate the association between dietary acid load and odds of IBS, its severity, and IBS subtypes. A sample of 3362 Iranian subjects was selected from health centers in Isfahan province. A validated semi-quantitative food frequency questionnaire (DS-FFQ) was applied to estimate dietary intakes. The dietary acid load was measured using net endogenous acid production (NEAP), dietary acid load (DAL), and potential renal acid load (PRAL) scores. In crude models, the highest compared with the lowest category of the PRAL score was significantly associated with increased odds of IBS severity in participants with BMI ≥ 25 (kg/m2) (OR = 1.54; 95% CI = (1.03–2.32). Also, the results indicated a significant positive association between the PARL and odds of mixed subtype of IBS (OR = 1.74; 95% CI = (1.11–2.74); P trend = 0.02). In propensity score-adjusted model with potential confounders, only a positive association was found between PRAL and odds of mixed subtype of IBS (OR = 1.78; 95% CI = (1.05–3.00); P trend = 0.03). The DAL and NEAP scores tended to show non-significant similar findings. This study indicates that dietary acid load might be associated with odds of mixed type of IBS. However, further research is warranted to infer these findings.

S525 The Low FODMAP Diet Improves Abdominal and Overall Symptoms in Patients With All Subtypes of Irritable Bowel Syndrome

Introduction: There is substantial evidence that a diet low in fermenTable oligo-, di-, monosaccharides, and polyols (FODMAPs) improves symptoms in patients with Irritable Bowel Syndrome and diarrhea (IBS-D). Though the low-FODMAP diet is increasingly used in patients with IBS and constipation (IBS-C) or mixed bowel habits (IBS-M), there is little data to support this practice. We aim to compare the real-world effectiveness of a low-FODMAP diet in patients with IBS-D, IBS-C, and IBS-M. Methods: Utilizing a commercially available meal procurement service which prepares and delivers meals certified low in FODMAP content (Modify Health, Atlanta, GA), patients with suspected IBS met with a registered dietitian and completed the IBS symptom severity scale (IBS-SSS) questionnaire before starting the low-FODMAP diet and after the restriction phase of the diet plan. A decrease in IBS-SSS score of >100 was defined as a responder. Results: 403 IBS patients filled out baseline and post-elimination IBS-SSS surveys. 26% of patients were referred by a GI specialist; the rest were self-referrals. 193 (48%) patients had severe IBS (IBS-SSS > 300) prior to the intervention. IBS-D patients had a 71% improvement in pain, 56% improvement in bloating, and 55% improvement in bowel movement satisfaction. 77% of IBS-D patients had improvement in total IBS-SSS >100. IBS-C patients had a 69% improvement in pain, 49% improvement in bloating, and 42% improvement in bowel movement satisfaction. 67% of IBS-C patients had improvements in IBS-SSS >100. IBS-M patients had 85% improvement in pain, 55% improvement in bloating, and 53% improvement in bowel movement satisfaction. 72% of IBS-M patients had improvement in total IBS-SSS >100. Those who used the commercial meals for "all" of the restriction phase had a mean IBS-SSS improvement of 174, and mean quality of life (QOL) improvement of 40%, while those who used the commercial meals for "some" of the elimination phase had mean IBS-SSS improvement of 153, and mean QOL improvement of 33% (p=0.059 and 0.03, respectively). (Table) Conclusion: This data supports the effectiveness of a low-FODMAP diet for all IBS subtypes, including IBS-C and IBS-M. Patients who obtained prepared low-FODMAP meals during the entire restriction phase experienced greater benefits than those who only obtained meals for a portion of the restriction phase. Table 1. - Improvement in IBS-SSS Categories by IBS-Subtype IBS Subtype Total Number of Patients IBS-SSS (Mean % Improvement) Pain (Mean % Improvement) Bloating (Mean % Improvement) BM Satisfaction (Mean % Improvement) % Improvement in IBS-SSS >100 IBS-D 87 59 (p< 0.001) 72 56 56 77 IBS-C 73 50 (p< 0.001) 70 49 42 67 IBS-M 91 56 (p< 0.001) 73 55 53 73

S570 Comparison of Quality of Life Between Patients With Diarrhea- and Constipation-Predominant Irritable Bowel Syndrome

Introduction: Irritable bowel syndrome (IBS) is characterized by recurrent abdominal pain and change in the form and consistency of stool. Two subtypes of IBS are diarrhea-predominant IBS (IBS-D) and constipation-predominant IBS (IBS-C). While IBS symptoms have been shown to decrease quality of life (QOL), the effects of IBS subtypes on QOL are still unclear. The aim of this study was to compare QOL parameters in patients with IBS-D and IBS-C. Methods: Data were obtained as part of an institutional review board-approved study where participants with ROME III positive criteria for IBS-D and IBS-C completed the following validated questionnaires: Bowel Disease Questionnaire, IBS-QOL, Hospital Anxiety and Depression Scale (HADS), Symptom Checklist 90 (SCL-90). We used two sample t-test, Wilcoxon rank sum test, and Pearson chi squared to compare the results between the two groups. Results: The study included 219 patients with IBS-D and 33 with IBS-C. The participants’ demographics are reported in the Table. Most patients with IBS-C (70%) had 2-4 bowel movements (BM) per week, while 48% of patients with IBS-D had 13-26 BM per week and 13% had more than 26 BM per week. Patients with IBS-D had higher anxiety, depression, and total anxiety-depression scores on the HADS compared to patients with IBS-C (Table). Patients with IBS-D had higher scores (reflecting worse symptoms) on the somatization, obsessive compulsive, depression, anxiety, and psychoticism dimensions as measured by the SCL-90. Moreover, patients with IBS-D had higher (reflecting worse) IBS-QOL total and subscale scores on 7 out of the 8 subscales (Table). Notably, 42% of patients with IBS-D felt like they were slightly or moderately losing control of their lives because of their bowel problems, whereas 92% of patients with IBS-C reported not feeling loss of control at all. While 96% of patients with IBS-C did not feel that their life revolved around their bowel movements, 20% of patients with IBS-D reported life revolved around their bowel movements quite a bit or a great deal, specifically due to needing to be in proximity to a toilet and inability to take long trips. Conclusion: Our study shows that patients with IBS-D seem to have a worse general and IBS-specific quality of life compared to patients with IBS-C. These data reinforce the importance of considering QOL impact of IBS and opportunities for shared decision-making when discussing individual management plans for patients with IBS-D. Table 1. - Comparison of demographic factors, Hospital Anxiety and Depression Scale, and IBS-Quality of Life subscale results in 219 patients with IBS-D and 33 patients with IBS-C IBS-D IBS-C P-value Demographics Age (years), mean (SD) 41 (14) 51 (12) 0.001 % females 79 100 0.004 BMI (kg/m2), mean (SD) 30 (7) 28 (6) 0.1878 Hospital Anxiety and Depression Scale (HADS) score, mean (SD) HADS total score 8.5 (5.2) 3.4 (2.6) < 0.0001 HADS anxiety score 6 (3.6) 2.5 (1.9) < 0.0001 HADS depression score 2.5 (2.3) 0.97 (1.1) 0.0006 IBS-Quality of Life total score, mean (95% CI) Total score 30.1 (27.6, 32.5) 9.1 (6.7, 11.5) < 0.0001 IBS-Quality of Life subscales, mean (95% CI) Dysphoria 28.1 (24.8, 31.5) 4.2 (1.9, 6.4) < 0.0001 Interference with activity 37.2 (34.2, 40.2) 7.1 (4.3, 10.0) < 0.0001 Proximity to toilet important: grades (1-5) 6/27/24/20/22% 59/37/4/0/0% < 0.0001 Long trips difficult: grades (1-5) 14/32/20/19/16% 78/19/4/0/0% < 0.0001 Body image 26.9 (24.2, 29.6) 18.3 (13.6, 23.0) 0.0249 Food avoidance 52.7 (48.5, 56.9) 13.0 (8.0, 17.9) < 0.0001 Social reaction 27.5 (24.5, 30.5) 8.1 (4.0, 12.2) < 0.0001 Sexual 17.2 (14.1, 20.2) 8.3 (2.8, 13.8) 0.0425 Relationship 20.1 (17.5, 22.8) 3.7 (1.4, 6.0) < 0.0001 SD=standard deviation; CI=confidence interval. Italicized factors reflect participants’ answers on a 1-5 scale for the interference with activity subscale, with 1 being “not at all” and 5 being “extremely”; higher scores reflect worse QOL.