Face-to-face interviews versus Internet surveys: Comparison of two data collection methods in the Rome foundation global epidemiology study: Implications for population-based research

BACKGROUND AND AIMS

The Rome Foundation Global Epidemiology Study (RFGES) assessed the prevalence, burden, and associated factors of Disorders of Gut-Brain Interaction (DGBI) in 33 countries around the world. Achieving worldwide sampling necessitated use of two different surveying methods: In-person household interviews (9 countries) and Internet surveys (26 countries). Two countries, China and Turkey, were surveyed with both methods. This paper examines the differences in the survey results with the two methods, as well as likely reasons for those differences.

METHODS

The two RFGES survey methods are described in detail, and differences in DGBI findings summarized for household versus Internet surveys globally, and in more detail for China and Turkey. Logistic regression analysis was used to elucidate factors contributing to these differences.

RESULTS

Overall, DGBI were only half as prevalent when assessed with household vs Internet surveys. Similar patterns of methodology-related DGBI differences were seen within both China and Turkey, but prevalence differences between the survey methods were dramatically larger in Turkey. No clear reasons for outcome differences by survey method were identified, although greater relative reduction in bowel and anorectal versus upper gastrointestinal disorders when household versus Internet surveying was used suggests an inhibiting influence of social sensitivity.

CONCLUSIONS

The findings strongly indicate that besides affecting data quality, manpower needs and data collection time and costs, the choice of survey method is a substantial determinant of symptom reporting and DGBI prevalence outcomes. This has important implications for future DGBI research and epidemiological research more broadly.

Pictograms are more effective than verbal descriptors in Spanish for bloating and distension

BACKGROUND

There is no translation for bloating in Spanish, and distension is very technical.

AIMS

To evaluate pictograms for assessing bloating/distension in patients with general gastroenterology (Study 1, n = 88) and in those with irritable bowel syndrome [IBS] (Study 2: n = 144), and to correlate them with verbal descriptors (VDs) and physician's diagnosis (PDx).

METHODS

Patients answered the Rome III Questionnaire with VDs and pictograms, and were consulted by two gastroenterology fellows (PDx). Correlations were conducted with Cohen's kappa, and ROC curves were used to contrast pictograms and VDs with PDx.

RESULTS

"Inflammation" was the most frequent VDs, while distension was commonly interpreted as a sensation ("inflammation") and/or increased abdominal girth. In patients not reporting bloating/distension with VDs, pictograms detected these symptoms in (Study 1 and Study 2) 82.2 and 89.6% of patients. In addition, pictograms showed a positive agreement with PDx, kappa: 0.63 (p < 0.0001) and 0.8 (p < 0.0001); and a negative agreement with VD, kappa: -0.45 (p = 0.05) and -0.1 (p = 0.2), respectively, in studies 1 and 2. Pictograms were more sensitive and specific than VDs (Study 1: ROC = 0.90 (95% CI: 0.80-0.96), p < 0.0001 versus 0.74 (0.62-0.88), p < 0.0001; Study 2: 0.99 (0.98-1.00), p = 0.004 versus 0.32 (0.10-0.54), p = 0.294).

CONCLUSIONS

Pictograms are more effective than Spanish VDs for bloating/distension in patients consulting for gastroenterology problems and those with IBS, supporting their usefulness in the clinic and research studies.

Greater Overlap of Rome IV Disorders of Gut-Brain Interactions Leads to Increased Disease Severity and Poorer Quality of Life

BACKGROUND AND AIMS

Conditions such as irritable bowel syndrome (IBS), functional dyspepsia, and functional constipation are among the prevalent gastrointestinal (GI) disorders classified as disorders of gut-brain interaction (DGBI), which can adversely affect the lives of sufferers. This study aimed to assess the degree and consequences of overlapping DGBI in a large population-based global scale.

METHODS

Internet survey data from 54,127 adults (49.1% women) in 26 countries were analyzed by 4 GI anatomic regions (esophageal, gastroduodenal, bowel, and anorectal). The number of DGBI-affected GI regions was assessed, including associations with sex, age, disease severity, quality of life, psychosocial variables, and health care utilization.

RESULTS

A total of 40.3% of surveyed individuals met Rome IV criteria for a DGBI. The percentages with 1-4 DGBI-affected GI regions were 68.3%, 22.3%, 7.1%, and 2.3%, respectively. The IBS symptom severity score increased significantly from 1 (207.6) to 4 (291.6) regions, as did non-GI symptom reporting (somatization), anxiety and depression, concerns and embarrassment about bowel function, doctor visits, medications, and abdominal surgeries (all P < .0001). Quality of life decreased with increasing number of DGBI regions (P < .0001). In a logistic mixed model, non-GI symptoms (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.08-1.10), being very vs not concerned (OR, 2.55; 95% CI, 2.27-2.90), being very vs not embarrassed about bowel function (OR, 1.20; 95% CI, 1.08-1.33), and mean number of doctor visits (OR, 1.23; 95% CI, 1.115-1.32) were most strongly associated with number of DGBI regions.

CONCLUSIONS

DGBI in multiple anatomic GI regions is associated with increased psychological comorbidity, health care utilization, and IBS severity. Physician awareness of overlap could improve quality of care, prevent unnecessary interventions, and yield more positive health outcomes.

Bacterial and Fungal Gut Dysbiosis and Clostridium difficile in COVID-19: A Review

BACKGROUND

Gastrointestinal symptoms are common in Coronavirus Disease 2019 (COVID-19), related to infection of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) of intestinal cells through the angiotensin converting enzyme 2 (ACE2) receptor in the brush border. Also, patients are treated with multiple antibiotics. Therefore, an increase in gut dysbiosis and in the prevalence of Clostridium difficile infection (CDI) is expected in patients with COVID-19.

METHODS

A PubMed search was conducted using the terms "gut microbiota," "gut mycobiota," "dysbiosis" AND "COVID-19"; "Clostridium difficile," "Clostridioides difficile" AND "COVID-19"; "probiotics," "bacteriotherapy AND COVID-19." Only case series, observational and experimental studies were included.

RESULTS

A total of 384 papers were retrieved and 21 fulfilled selection criteria. Later, a new paper was identified, thus 22 papers were reviewed. Main findings: (1) gut bacterial dysbiosis has been found in fecal samples of COVID-19 patients, with enrichment of opportunistic organisms and decrease of beneficial commensals such as Faecalibacterium prausnitizii. Dysbiosis is related to inflammatory markers and illness severity. (2) There is evidence for abnormal gut barrier and bacterial translocation with a negative impact in the lungs. (3) Fungal dysbiosis correlating with pulmonary mycobiota, has also been found. (4) There is controversy in the CDI rates among COVID-19 patients versus controls and pandemic versus prepandemic era. (5) There is no available evidence yet to support bacteriotherapy in COVID-19. (6) Fecal microbiota transplantation (FMT) has been proposed for COVID-19, although there is no evidence to support it. Also, FMT can be safely used during the pandemic for CDI if strict screening protocols for donors and fecal product are implemented.

CONCLUSIONS

In COVID-19 there is bacterial and fungal dysbiosis that correlates with systemic and pulmonary inflammation, and illness severity. Further investigations are warranted to determine the efficacy of bacteriotherapy and FMT for modulating gut dysbiosis in COVID-19.

The Impact of COVID-19 Pandemic on Neurogastroenterologists in Latin America: Results of an Online Survey

BACKGROUND

The COVID-19 pandemic has affected medical practice in fields not related to the infection. Neurogastroenterology is a subspecialty of gastroenterology focused on motility and functional gastrointestinal disorders, including consultations, and conducting procedures (eg, endoscopies, manometries/pH-monitoring).

AIM

The aim of this study was to determine the impact of COVID-19 on Neurogastroenterology in Latin America.

METHODS

Members of the Latin American Society of Neurogastroenterology were invited by e-mail and social networks to participate in an online anonymous survey. It included 24 questions on demographics, clinical practice and procedure characteristics, impact of the pandemic, Telemedicine, and involvement in COVID-19 patient care.

RESULTS

Sixty-one members mainly from Colombia, Mexico, and Brazil answered the survey. All reported a negative impact on their practice (88.6%: a 61% to 100% decrease), mainly in office consultations and elective endoscopies. Interestingly, emergency endoscopies decreased by 33.3%, while only 4% stopped performing manometries/pH-monitoring. The main reasons were patients' fear for consulting, country's lockdown, and physician's decision to prevent infection spread. Telemedicine was implemented by 83% but only 64.7% were being remunerated. Almost 46% had to reduce salaries and working hours of their personnel. Fifty-nine percent had colleagues diagnosed with COVID-19, 24.6% were involved in these patients' care, and 11.5% were mobilized to COVID-19 wards. There were country differences: Colombia, lockdown (P=0.001); Mexico, COVID-19 patient-care (P=0.053); Mexico/Colombia, working in COVID-19 wards, (P=0.012); Brazil, less common elective procedures' ban (P=0.012) and Telemedicine/reimbursement (P=0.034).

CONCLUSIONS

The COVID-19 pandemic has negatively impacted the practice and wellness of Neurogastroenterologists in Latin America. Guidelines to resume activities and policies for Telemedicine practice and reimbursement are warranted.

Degree of concordance on the management of patients with gastroesophageal reflux disease. A study among specialists that are members of the Sociedad Latinoamericana de Neurogastroenterología (SLNG)

INTRODUCTION AND AIMS

Due to its different clinical manifestations, gastroesophageal reflux disease (GERD) requires diverse diagnostic and therapeutic interventions. The aim of the study was to evaluate the degree of concordance among Latin American specialists, with respect to the management of GERD.

MATERIALS AND METHODS

A cross-sectional study was conducted through a survey with 42 statements (22 related to diagnosis and 20 to treatment) applied to 56 specialists from Latin America. There were 4 possible statement responses: in complete agreement, in partial agreement, in partial disagreement, and in complete disagreement. Reproducibility, level of agreement, and concordance were measured through the Kappa statistic.

RESULTS

The response rate was 81% (47/56). General concordance was low, given that there was complete concordance in only 12 statements (28.6%). There was partial concordance in 22 statements (52.4%) and no concordance in 8 (19%). The following themes had the most disagreement: the performance of endoscopy before beginning treatment, the use of proton pump inhibitors (PPIs) in patients with extraesophageal symptoms and with no typical symptoms, and the combined use of PPIs and prokinetics.

CONCLUSIONS

In the present study, we found that there was agreement among the Latin American specialists for the diagnosis and management of GERD in less than one-third of the recommendations considered standard. The low concordance could be related to the fact that the availability of diagnostic tools and medications, as well as the prevalence of GERD phenotypes, are different in each country.

Probiotics: To Use or Not to Use? That Is the Question

ABSTRACT

This Editorial analyzes the paper by Schnadower et al on the secondary analysis of 2 randomized placebo-controlled trials evaluating the efficacy of Lactobacillus rhamnosus GG, and a combination of L. rhamnosus R0011 and L. helveticus R0052, showing that moderate-to-severe gastroenteritis symptoms as primary endpoint, did not differ between probiotics or placebo. The data is important because probiotics are commonly used and prescribed in clinical practice, many times without strong evidence and producing a high economic burden. Two other examples are addressed. A systematic review of randomized placebo-controlled trial of L. reuteri DSM 17938 finding that this probiotic reduced the duration of diarrhea and hospitalization, to discuss the issue that the effect of probiotics is strain specific. In addition, the different findings of reviews and meta-analyses of probiotics in Irritable Bowel Syndrome in which a common conclusion of all of them was that adequately powered randomized controlled trials are required to better determine the species, strains and doses of probiotics, as well as the treatment duration that is most efficacious. Finally, the fact that probiotics are frequently prescribed despite lacking regulations by pharmaceutical authorities is addressed.

Worldwide Prevalence and Burden of Functional Gastrointestinal Disorders, Results of Rome Foundation Global Study

BACKGROUND & AIMS

Although functional gastrointestinal disorders (FGIDs), now called disorders of gut-brain interaction, have major economic effects on health care systems and adversely affect quality of life, little is known about their global prevalence and distribution. We investigated the prevalence of and factors associated with 22 FGIDs, in 33 countries on 6 continents.

METHODS

Data were collected via the Internet in 24 countries, personal interviews in 7 countries, and both in 2 countries, using the Rome IV diagnostic questionnaire, Rome III irritable bowel syndrome questions, and 80 items to identify variables associated with FGIDs. Data collection methods differed for Internet and household groups, so data analyses were conducted and reported separately.

RESULTS

Among the 73,076 adult respondents (49.5% women), diagnostic criteria were met for at least 1 FGID by 40.3% persons who completed the Internet surveys (95% confidence interval [CI], 39.9-40.7) and 20.7% of persons who completed the household surveys (95% CI, 20.2-21.3). FGIDs were more prevalent among women than men, based on responses to the Internet survey (odds ratio, 1.7; 95% CI, 1.6-1.7) and household survey (odds ratio, 1.3; 95% CI, 1.3-1.4). FGIDs were associated with lower quality of life and more frequent doctor visits. Proportions of subjects with irritable bowel syndrome were lower when the Rome IV criteria were used, compared with the Rome III criteria, in the Internet survey (4.1% vs 10.1%) and household survey (1.5% vs 3.5%).

CONCLUSIONS

In a large-scale multinational study, we found that more than 40% of persons worldwide have FGIDs, which affect quality of life and health care use. Although the absolute prevalence was higher among Internet respondents, similar trends and relative distributions were found in people who completed Internet vs personal interviews.

Ethnicity and other COVID-19 death risk factors in Mexico

Introduction

Patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may develop coronavirus disease 2019 (COVID-19). Risk factors associated with death vary among countries with different ethnic backgrounds. We aimed to describe the factors associated with death in Mexicans with confirmed COVID-19.

Material and methods

We analysed the Mexican Ministry of Health's official database on people tested for SARS-CoV-2 infection by real-time reverse transcriptase-polymerase chain reaction (rtRT-PCR) of nasopharyngeal fluids. Bivariate analyses were performed to select characteristics potentially associated with death, to integrate a Cox-proportional hazards model.

Results

As of May 18, 2020, a total of 177,133 persons (90,586 men and 86,551 women) in Mexico received rtRT-PCR testing for SARS-CoV-2. There were 5332 deaths among the 51,633 rtRT-PCR-confirmed cases (10.33%, 95% CI: 10.07-10.59%). The median time (interquartile range, IQR) from symptoms onset to death was 9 days (5-13 days), and from hospital admission to death 4 days (2-8 days). The analysis by age groups revealed that the significant risk of death started gradually at the age of 40 years. Independent death risk factors were obesity, hypertension, male sex, indigenous ethnicity, diabetes, chronic kidney disease, immunosuppression, chronic obstructive pulmonary disease, age > 40 years, and the need for invasive mechanical ventilation (IMV). Only 1959 (3.8%) cases received IMV, of whom 1893 were admitted to the intensive care unit (96.6% of those who received IMV).

Conclusions

In Mexico, highly prevalent chronic diseases are risk factors for death among persons with COVID-19. Indigenous ethnicity is a poorly studied factor that needs more investigation.

Beware: Gastrointestinal symptoms can be a manifestation of COVID-19

Background

There is a growing number of reports of COVID-19 cases presenting gastrointestinal (GI) symptoms.

Aims

To review studies reporting GI symptoms among COVID-19 patients.

Results

Fifteen papers (2800 patients) were identified. Frequency of GI symptoms varied from 3.0% to 39.6%, including diarrhea: 7.5%, nausea: 4.5%, anorexia: 4.4%, vomiting: 1.3%, abdominal pain: 0.5%, belching/reflux: 0.3%. These may be the first manifestation of COVID-19, however, there is controversy whether these reflect better or worst prognosis. Finally, the potential relationship with the angiotensin converting enzyme 2 (ACE2) cell receptor in the digestive tract as the virus entry route, is discussed.

Conclusions

GI symptoms may be common in COVID-19 and may be the first manifestation before fever and respiratory symptoms. Therefore, clinicians and gastroenterologists need to be aware of these atypical cases during the current pandemic and of the fecal–oral transmission, and preventive measures may be implemented.

Beware: Gastrointestinal symptoms can be a manifestation of COVID-19

BACKGROUND

There is an increasing number of reports on the presentation of gastrointestinal symptoms in cases of COVID-19.

AIM

To review the studies reporting gastrointestinal symptoms in COVID-19.

RESULTS

Fifteen articles (2,800 patients) were identified. Gastrointestinal symptom frequency varied from 3.0% to 39.6% and included diarrhea (7.5%), náusea (4.5%), anorexia (4.4%), vomiting (1.3%), abdominal pain (0.5%), and belching/reflux (0.3%). Those symptoms can be the first manifestation of COVID-19, but whether they reflect a better or worse prognosis, is controversial. The potential relation of the angiotensin converting enzyme 2 receptor in the digestive tract as an entry route for the virus is discussed.

CONCLUSION

Gastrointestinal symptoms may be common in COVID-19, in some cases appearing as the first manifestation, even before fever and respiratory symptoms. Therefore, clinicians and gastroenterologists must be aware of those atypical cases during the current pandemic, as well as of the fecal-oral route and corresponding preventive measures.

Mucosal Microbiome Profiles Polygenic Irritable Bowel Syndrome in Mestizo Individuals

Irritable bowel syndrome (IBS) is the most frequent functional gastrointestinal disorder, worldwide, with a high prevalence among Mestizo Latin Americans. Because several inflammatory disorders appear to affect this population, a further understanding of host genomic background variants, in conjunction with colonic mucosa dysbiosis, is necessary to determine IBS physiopathology and the effects of environmental pressures. Using a simple polygenic model, host single nucleotide polymorphisms (SNPs) and the taxonomic compositions of microbiota were compared between IBS patients and healthy subjects. As proof of concept, five IBS-Rome III patients and five healthy controls (HCs) were systematically studied. The human and bacterial intestinal metagenome of each subject was taxonomically annotated and screened for previously annotated IBS, ulcerative colitis, and Crohn's disease-associated SNPs or taxon abundance. Dietary data and fecal markers were collected and associated with the intestinal microbiome. However, more than 1,000 variants were found, and at least 76 SNPs differentiated IBS patients from HCs, as did associations with 4 phyla and 10 bacterial genera. In this study, we found elements supporting a polygenic background, with frequent variants, among the Mestizo population, and the colonic mucosal enrichment of Bacteroides, Alteromonas, Neisseria, Streptococcus, and Microbacterium, may serve as a hallmark for IBS.

A low frequency of post infection-IBS in patients attended in a tertiary referral center in México

BACKGROUND

PI-IBS prevalence is around 10.1%-14.5% ≥ 12 months after infectious gastroenteritis in North America, Europe and Asia. However, there are no studies from Latin America. Two previous studies in Mexico suggest a low incidence of 5%.

AIMS

to determine the prevalence of PI-IBS in patients attended in a tertiary-care center, as well as IBS subtypes, severity, other digestive symptoms and red flags vs nPI-IBS.

METHODS

seventy IBS patients screened for immunological research completed the Rome III, Spiller's for PI-IBS and IBS-SSS questionnaires. PI-IBS prevalence was determined according to three criteria sets. C1: ≥ 2 episodes of sudden onset, onset while traveling, initial illness with any of the following symptoms, fever, vomiting, bloody diarrhea and a positive stool culture. C2: sudden onset and > 2 episodes of fever, diarrhea, vomiting and bloody diarrhea. C3: sudden onset after an infectious episode such as a positive culture or onset with ≥ 2 episodes of fever, vomiting, diarrhea, rectal bleeding and foreign travel. Items were dichotomized as present or absent and compared using the Fisher's exact and Mann-Whitney U tests.

RESULTS

PI-IBS prevalence was as follows. C1: 5.7%, C2: 0 and C3: 1.4%. There were no IBS-C or IBS-M cases. In the C1 group, one case was mild and three were moderate IBS, which was similar to the non PI-IBS group. One case in the C3 group had mild IBS. There were no differences in the frequency of esophageal, gastroduodenal, anorectal, bloating/distension and red flags between PI-IBS and non PI-IBS groups (analyzed only for C3).

CONCLUSIONS

in Mexico, there is a very low prevalence of PI-IBS in patients from a tertiary-referral center. However, it varies according to the surrogate-criteria used. The later needs to be taken into account when performing PI-IBS studies.

Functional gastrointestinal disorders in women with systemic lupus erythematosus: A case-control study

BACKGROUND

Systemic lupus erythematosus (SLE) is an autoimmune disease with multisystemic involvement. Gastrointestinal (GI) manifestations are frequent but functional gastrointestinal disorders (FGIDs) have scarcely been studied in SLE. To determine the prevalence of FGIDs and their potential risk factors in SLE female patients vs controls.

METHODS

Systemic lupus erythematosus patients meeting the American College of Rheumatology (ACR) criteria and controls completed the Rome III questionnaire for FGIDs and a structured interview to assess sociodemographic, clinical, and treatment variables after excluding organic GI diseases. Logistic regression was used to determine risk factors (ie, alcohol drinking, medications) for FGIDs.

KEY RESULTS

Responders included 113 SLE patients and 122 age-matched controls. The presence of at least one FGIDs was higher in SLE (73.4%) vs controls (54.1%), P = .003. The most frequent FGIDs in SLE patients were nausea and vomiting disorders (NVD), belching disorders, globus, anorectal pain, functional heartburn (FH), and functional bloating (FB). After adjustment for confounding variables, SLE was associated with NVD (OR: 7.1, 95% CI: 2.7-19.1) globus (3.5, 1.3-9.3), anorectal pain (3.4, 1.4-8.4), and FH (2.5, 1.5-4.4). The simultaneous presence of >1 FGID was more common in SLE patients than controls (69.8% vs 31.8%). Glucocorticoids (5.2, 1.3-19.9) and non-steroidal anti-inflammatory drugs (NSAIDs; 3.0, 1.1-8.0) were associated with any FGID in SLE patients while alcohol drinking with gallbladder/sphincter of Oddi disorders 7.4 (1.1-47.3).

CONCLUSIONS AND INFERENCES

Functional gastrointestinal disorders are more frequent in SLE patients compared with controls. Medication that may alter gastrointestinal homeostasis, such as glucocorticoids and NSAIDs, are potential risk factors for FGIDs in SLE.

[Diagnostic and therapeutic approach to dyspepsia and functional dyspepsia:what's new in 2019?]

Dyspepsia encompasses a set of symptoms that originate in the gastroduodenal region. It is characterized by pain or epigastric burning, early satiety and post-prandial fullness. According to the relationship of symptoms with meals, it is divided into epigastric pain syndrome and postprandial distress syndrome. However, in clinical practice, they frequently overlap. In recent years the paradigm of gastric physiological alterations has been changed and evidence supporting duodenal eosinophilia has increased, as a primary alteration that alters gastric physiology and can induce symptomatology. Every day there is more interest in the alteration of the microbiota. The treatment is based on the suppression of acid, neuromodulators, prokinetics, psychotherapy, alternative and complementary therapies. No treatment is effective in all patients.

Fecal microbiota transfer for bowel disorders: efficacy or hype?

PURPOSE OF REVIEW

Dysbiosis has been related to the pathophysiology of disorders of - gut-brain interaction (DGBI) including irritable bowel syndrome (IBS) and functional constipation (FC). Accordingly, modulation of gut microbiota has been proposed as a potential treatment for these disorders. Gut microbiota modulation can be effected by probiotics, prebiotics, symbiotics, postbiotics, antibiotics and fecal transplantation (FMT) or bacteriotherapy. The latter is currently used for recurrent or severe Clostridium difficile colitis and has been the focus of recent research in IBS and FC.

RECENT FINDINGS

Several case series reported promising results for FMT in patients with IBS and FC, which prompted the conduction of randomized controlled trials (RCT) in these DGBI.

SUMMARY

Both case series and RCTs are herein discussed. To the best of our knowledge, as of yet, 5 RCTs have been published on IBS and one in FC with slow colonic transit. In IBS, the majority of studies have used the IBS severity scoring system (IBS-SSS) as an outcome measure; however, the selection criteria were different among the trials as well as the route and form of administration of the FMT. Therefore, the results are inconsistent and no conclusion can be drawn. Some studies suggest that the presence of post-infection (PI)-IBS and the baseline microbiota status in the donors could be predictor factors of successful FMT in IBS. In constipation with slow colonic transit, the FMT seems to be more effective, although the data is based on only one RCT. We believe that larger RCTs, controlled with true placebos and considering baseline intestinal microbiota of the study subjects as well as donors' microbiota are still needed before recommending FMT in IBS and/or FC. History of previous GI infection (e.g. PI-IBS) and IBS subtypes should also be taken into account.

The global prevalence of IBS in adults remains elusive due to the heterogeneity of studies: a Rome Foundation working team literature review

OBJECTIVES

The global prevalence of IBS is difficult to ascertain, particularly in light of the heterogeneity of published epidemiological studies. The aim was to conduct a literature review, by experts from around the world, of community-based studies on IBS prevalence.

DESIGN

Searches were conducted using predetermined search terms and eligibility criteria, including papers in all languages. Pooled prevalence rates were calculated by combining separate population survey prevalence estimates to generate an overall combined meta-prevalence estimate. The heterogeneity of studies was assessed.

RESULTS

1451 papers were returned and 83, including 288 103 participants in 41 countries, met inclusion criteria. The mean prevalence among individual countries ranged from 1.1% in France and Iran to 35.5% in Mexico. There was significant variance in pooled regional prevalence rates ranging from 17.5% (95% CI 16.9% to 18.2%) in Latin America, 9.6% (9.5% to 9.8%) in Asia, 7.1% (8.0% to 8.3%) in North America/Europe/Australia/New Zealand, to 5.8% (5.6% to 6.0%) in the Middle East and Africa. There was a significant degree of heterogeneity with the percentage of residual variation due to heterogeneity at 99.9%.

CONCLUSIONS

The main finding is the extent of methodological variance in the studies reviewed and the degree of heterogeneity among them. Based on this, we concluded that publication of a single pooled global prevalence rate, which is easily calculated, would not be appropriate or contributory. Furthermore, we believe that future studies should focus on regional and cross-cultural differences that are more likely to shed light on pathophysiology.

Hydrogen and Methane-Based Breath Testing in Gastrointestinal Disorders: The North American Consensus

OBJECTIVES

Breath tests (BTs) are important for the diagnosis of carbohydrate maldigestion syndromes and small intestinal bacterial overgrowth (SIBO). However, standardization is lacking regarding indications for testing, test methodology and interpretation of results. A consensus meeting of experts was convened to develop guidelines for clinicians and research.

METHODS

Pre-meeting survey questions encompassing five domains; indications, preparation, performance, interpretation of results, and knowledge gaps, were sent to 17 clinician-scientists, and 10 attended a live meeting. Using an evidence-based approach, 28 statements were finalized and voted on anonymously by a working group of specialists.

RESULTS

Consensus was reached on 26 statements encompassing all five domains. Consensus doses for lactulose, glucose, fructose and lactose BT were 10, 75, 25 and 25 g, respectively. Glucose and lactulose BTs remain the least invasive alternatives to diagnose SIBO. BT is useful in the diagnosis of carbohydrate maldigestion, methane-associated constipation, and evaluation of bloating/gas but not in the assessment of oro-cecal transit. A rise in hydrogen of ≥20 p.p.m. by 90 min during glucose or lactulose BT for SIBO was considered positive. Methane levels ≥10 p.p.m. was considered methane-positive. SIBO should be excluded prior to BT for carbohydrate malabsorption to avoid false positives. A rise in hydrogen of ≥20 p.p.m. from baseline during BT was considered positive for maldigestion.

CONCLUSIONS

BT is a useful, inexpensive, simple and safe diagnostic test in the evaluation of common gastroenterology problems. These consensus statements should help to standardize the indications, preparation, performance and interpretation of BT in clinical practice and research.

Intestinal microbiota: a regulator of intestinal inflammation and cardiac ischemia?

Inflammatory bowel diseases (IBD) are chronic, relapsing and remitting gastrointestinal (GI) disorders of unknown etiology. IBD patients commonly exhibit extra-intestinal manifestations and complications of an inflammatory nature, presenting with disorders such as ankylosing spondylitis, uveitis and vasculitis. Although the metabolic syndrome is less prevalent in patients with IBD, they are at an increased risk for atherosclerosis and cardiovascular events. Considerable evidence supports the role of GI microbiota in the development of IBD. Recent studies have also shown a significant interaction between the metabolites of gut microbiota and the development of cardiovascular disease. Here we hypothesize that dysbiosis and/or abnormalities in the function of the intestinal microbiota promote cardiovascular disease in IBD patients, explaining the increased risk of cardiovascular events in these patients.

Increase in Mexican and Latin American scientific articles on irritable bowel syndrome

BACKGROUND

There is an implied perception that little scientific information on irritable bowel syndrome (IBS) comes out of Mexico and Latin America in the international medical literature, but the number and tendencies of articles from the region on IBS are not known.

AIMS

To determine the number and type of Mexican and Latin American articles on IBS published between 1990-2015.

METHODS

A systematic search of Medline was carried out employing the terms « Irritable Bowel Syndrome » or its abbreviation (IBS). Mexico and every other Latin American country were added to specify the search. The articles were selected if they were published in Mexico and/or the rest of Latin America, if they were international papers on IBS in the region, or if they were written by Mexican and/or Latin American authors. In addition, the articles were classified into the following categories: Reviews/Editorials/Letters to the Editor (REV/ED), Epidemiology/Quality of Life/Psychosocial Factors (EPI/QOL), Diagnostic (DX), Treatment (TX), and Translational/Pathophysiologic (TRANS) studies.

RESULTS

A total of 66 articles from Mexico and 47 from Latin America were identified, but only 87.7 and 48.9%, respectively, fit the selection criteria. Category distribution was: EPI/QOL: 36.2%, REV/ED: 27.5%, TRANS: 18.8, TX: 10%, and DX: 7.5% and was similar between Mexico and Latin America (p=0.33). The year 2005 saw an increase in the number of articles in Mexico, with a peak in 2010. The figures for Latin American articles remained stable over the years, with a peak in 2012.

CONCLUSIONS

A noticeable increase has been observed over the last decade in the research conducted on IBS in Mexico and Latin America. Even though the EPI/QOL studies predominate, the sophistication of research is reflected in the TRANS studies that are in third place of frequency. The information referred to herein demonstrates maturity in the field, making it possible to carry out consensuses based on local data.

A cross-cultural investigation of attachment style, catastrophizing, negative pain beliefs, and symptom severity in irritable bowel syndrome

BACKGROUND

Little information exists regarding whether psychosocial variables in irritable bowel syndrome (IBS) vary by geographic location. Adult attachment is an important psychological concept rooted in childhood relationship experience that has not been previously studied in IBS. Catastrophizing and negative pain beliefs have been described in IBS and may be affected by attachment.

AIMS

In this cross-cultural study, we determined: (i) whether attachment differs between IBS patients and controls, (ii) whether geographic location has a significant effect on attachment style, catastrophizing and negative pain beliefs, and (iii) how all three variables correlate with IBS symptom severity.

METHODS

463 IBS patients, with moderate to severe symptom scores, and 192 healthy controls completed validated questionnaires about attachment, catastrophizing, negative pain beliefs and IBS-SSS in nine locations, USA (New York, Los Angeles), Mexico, Italy (Rome, Bari), Romania, Iran, India, and China.

KEY RESULTS

Attachment anxiety and avoidance scores were significantly higher in IBS patients than in controls (p < 0.001). This was particularly true for the fearful-avoidant attachment category, especially in China and Romania. Path analysis showed that attachment anxiety and avoidance had indirect effects on IBS-SSS through catastrophizing (p < 0.0001) and negative pain beliefs (p = 0.005). All three psychosocial measures varied significantly depending on location.

CONCLUSIONS & INFERENCES

In the IBS population studied, attachment style was significantly different in IBS compared to a control population. Geographic differences in attachment, catastrophizing and negative pain beliefs were documented and their correlation with symptom severity and thus, research of psychosocial variables in IBS should take into account the location of the population studied.

Conducting multinational, cross-cultural research in the functional gastrointestinal disorders: issues and recommendations. A Rome Foundation working team report

BACKGROUND

Cross-cultural, multinational research can advance the field of functional gastrointestinal disorders (FGIDs). Cross-cultural comparative research can make a significant contribution in areas such as epidemiology, genetics, psychosocial modulators, symptom reporting and interpretation, extra-intestinal co-morbidity, diagnosis and treatment, determinants of disease severity, health care utilisation, and health-related quality of life, all issues that can be affected by geographical region, culture, ethnicity and race.

AIMS

To identify methodological challenges for cross-cultural, multinational research, and suggest possible solutions.

METHODS

This report, which summarises the full report of a working team established by the Rome Foundation that is available on the Internet, reflects an effort by an international committee of FGID clinicians and researchers. It is based on comprehensive literature reviews and expert opinion.

RESULTS

Cross-cultural, multinational research is important and feasible, but has barriers to successful implementation. This report contains recommendations for future research relating to study design, subject recruitment, availability of appropriate study instruments, translation and validation of study instruments, documenting confounders, statistical analyses and reporting of results.

CONCLUSIONS

Advances in study design and methodology, as well as cross-cultural research competence, have not matched technological advancements. The development of multinational research networks and cross-cultural research collaboration is still in its early stages. This report is intended to be aspirational rather than prescriptive, so we present recommendations, not guidelines. We aim to raise awareness of these issues and to pose higher standards, but not to discourage investigators from doing what is feasible in any particular setting.

A four-country comparison of healthcare systems, implementation of diagnostic criteria, and treatment availability for functional gastrointestinal disorders: a report of the Rome Foundation Working Team on cross-cultural, multinational research

BACKGROUND

Variations in healthcare provision around the world may impact how patients with functional gastrointestinal disorder (FGIDs) are investigated, diagnosed, and treated. However, these differences have not been reviewed.

PURPOSES

The Multinational Working Team of the Rome Foundation, established to make recommendations on the conduct of multinational, cross-cultural research in FGIDs, identified seven key issues that are analyzed herein: (i) coverage afforded by different healthcare systems/providers; (ii) level of the healthcare system where patients with FGIDs are treated; (iii) extent/types of diagnostic procedures typically undertaken to diagnose FGIDs; (iv) physicians' familiarity with and implementation of the Rome diagnostic criteria in clinical practice; (v) range of medications approved for FGIDs and approval process for new agents; (vi) costs involved in treating FGIDs; and (vii) prevalence and role of complementary/alternative medicine (CAM) for FGIDs. Because it was not feasible to survey all countries around the world, we compared a selected number of countries based on their geographical and ethno-cultural diversity. Thus, we included Italy and South Korea as representative of nations with broad-based coverage of healthcare in the population and India and Mexico as newly industrialized countries where there may be limited provision of healthcare for substantial segments of the population. In light of the paucity of formal publications on these issues, we included additional sources from the medical literature as well as perspectives provided by local experts and the media. Finally, we provide future directions on healthcare issues that should be taken into account and implemented when conducting cross-cultural and multinational research in FGIDs.

Cytokine imbalance in irritable bowel syndrome: a systematic review and meta-analysis

BACKGROUND

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder of unknown etiology; although infection and inflammation have recently been considered as important etiologic agents. A recent meta-analysis showed correlations between cytokine [interleukin-10 (IL-10) and tumor necrosis factor (TNF)] gene polymorphisms and IBS; however, it is still unknown whether patients with IBS have different cytokine profiles compared to healthy population.

METHODS

To determine the relationships between serum/plasma levels or mucosal expression of IL-10/TNF-α and IBS, we conducted a systematic review and meta-analysis based on case-control studies retrieved from PubMed and EMBASE search through August 2013. Standardized mean difference (SMD) was generated by using the inverse variance method. Heterogeneity was assessed based on I(2) values.

KEY RESULTS

Serum/plasma levels of TNF-α tended to be higher in IBS vs controls (p = 0.09); this reached significance in IBS subtypes vs controls and in female patients with IBS. However, serum/plasma levels of IL-10 were not significantly different in IBS patients vs controls. Further analysis of serum/plasma IL-10 levels in IBS subtypes did not show any difference; however, analysis based on gender showed a significantly lower serum/plasma IL-10 levels in male patients with IBS vs male controls (p = 0.02). Colonic IL-10 mRNA had a significantly lower expression in IBS vs control (p = 0.001).

CONCLUSIONS & INFERENCES

There is an imbalance of proinflammatory TNF-α, and anti-inflammatory IL-10, cytokines in IBS. Stratifying IBS patients based on cytokine profile may represent an opportunity for personalized treatment of this condition.

Microbiota, gastrointestinal infections, low-grade inflammation, and antibiotic therapy in irritable bowel syndrome: an evidence-based review

BACKGROUND

Post-infectious irritable bowel syndrome (PI-IBS) prevalence, small intestinal bacterial overgrowth (SIBO), altered microbiota, low-grade inflammation, and antibiotic therapy in IBS are all controversial issues.

AIMS

To conduct an evidence-based review of these factors.

METHODS

A review of the literature was carried out up to July 2012, with the inclusion of additional articles as far as August 2013, all of which were analyzed through the Oxford Centre for Evidence-Based Medicine (OCEBM) system.

RESULTS

1.There is greater SIBO probability in IBS when breath tests are performed, but prevalence varies widely (2-84%). 2.The gut microbiota in individuals with IBS is different from that in healthy subjects, but a common characteristic present in all the patients has not been established. 3.The incidence and prevalence of PI-IBS varies from 9-10% and 3-17%, respectively, and the latter decreases over time. Bacterial etiology is the most frequent but post-viral and parasitic cases have been reported. 4.A sub-group of patients has increased enterochromaffin cells, intraepithelial lymphocytes, and mast cells in the intestinal mucosa, but no differences between PI-IBS and non-PI-IBS have been determined. 5.Methanogenic microbiota has been associated with IBS with constipation. 6.Rifaximin at doses of 400mg TID/10days or 550mg TID/14days is effective treatment for the majority of overall symptoms and abdominal bloating in IBS. Retreatment effectiveness appears to be similar to that of the first cycle.

CONCLUSIONS

Further studies are required to determine the nature of the gut microbiota in IBS and the differences in low-grade inflammation between PI-IBS and non-PI-IBS. Rifaximin has shown itself to be effective treatment for IBS, regardless of prior factors.

Irritable bowel syndrome-type symptoms in female patients with mild systemic lupus erythematosus: frequency, related factors and quality of life

BACKGROUND

Irritable bowel syndrome (IBS) impairs quality of life (HRQOL), as does systemic lupus erythematosus (SLE). Both are more common in women and are associated with fibromyalgia (FM). However, the relationship between IBS and SLE and its impact on HRQOL has not been explored. Therefore, we aimed to study the frequency and features likely to influence the presence of IBS-type symptoms in SLE and their impact on HRQOL.

METHODS

Female patients with SLE were studied. The presence of IBS-type symptoms and bowel habit subtype were established by Rome III criteria and HRQOL was assessed using the SF-36. Fibromyalgia and depression were assessed using the American College of Rheumatology criteria and CES-D scale, respectively.

KEY RESULTS

A total of 105 consecutive patients (43.62 ± 11.34 years old) were included; 48.6% had IBS-type symptoms (SLE+IBS) and were classified as IBS-C: 23.5%, IBS-D: 37.3%, and IBS-M: 39.2%. In addition, 23.8% had FM. SLE+IBS vs Non-IBS SLE patients had higher SLE activity scores (2.55 ± 1.65 vs 1.74 ± 2.19; p = 0.03), were more likely to have FM (33.0% vs 14.8%; p = 0.02) and depression (41.1% vs 25.9%, p = 0.04). Logistic multivariate analysis showed that IBS-type symptoms were associated with FM (OR = 2.85, 95% CI: 1.11-7.43) and depression (OR = 1.07, 95% CI: 1.02-1.13). Finally, SLE+IBS vs Non-IBS SLE patients had lower SF-36 scores (49.65 ± 18.57 vs 62.67 ± 18.14; p = 0.02).

CONCLUSIONS & INFERENCES

IBS-type symptoms are highly prevalent among women with SLE and are associated with FM and depression. SLE+IBS patients had worse HRQOL vs Non-IBS SLE, independently of FM status. We suggest that treating IBS symptoms may improve HRQOL in women with SLE.

Intestinal recruiting and activation profiles in peripheral blood mononuclear cells in response to pathogen-associated molecular patterns stimulation in patients with IBS

BACKGROUND

Immune activation, increased Toll-like Receptors (TLR) expression, and gut epithelial diffusion of bacterial molecules have been reported in irritable bowel syndrome (IBS). Thus, we sought to relate these factors by analyzing gut homing (integrin α4β7), intestinal recruiting (CCR5) and activation (CD28) phenotypes, and the cytokines and chemokines concentration in peripheral blood T-lymphocytes stimulated with TLR-ligands.

METHODS

Twenty-one IBS-Rome II (1 PI-IBS) patients and 19 controls were studied. Isolated peripheral blood mononuclear cells were cultured with and without Escherichia coli lipopolysaccharide (LPS), Staphylococcus aureus peptidoglycan (PGN), and unmethylated cytosine-phosphate-guanine motifs (CpG). Phenotypes were investigated by flow cytometry and supernatant cytokines and chemokines were also measured.

KEY RESULTS

After LPS, CCR5 expression in CD4⁺ α4β7⁺ cells remained unchanged in IBS, but decreased in controls (p = 0.002), to lower levels than in IBS (Mean fluorescence intensity [MFI]: 1590 ± 126.9 vs 2417 ± 88.4, p < 0.001). There were less CD8(+) α4β7⁺ CCR5⁺ cells (85.7 ± 1.5 vs 90.8 ± 0.9%, p = 0.006) after LPS and CD3⁺ α4β7⁺ CCR5⁺ (40.0 ± 1.7 vs 51.2 ± 4.3%, p = 0.006) after PGN in controls. Also, after LPS, CD28 decreased in CD4⁺ α4β7⁺ CCR5⁺ in IBS (MFI: 2337 ± 47.2 vs 1779 ± 179.2, p < 0.001), but not in controls. Cytokines and chemokines were similar, except for lower IL8/CXCL8 in the unstimulated condition in IBS (4.18, 95% CI: 3.94-4.42 vs 3.77, 3.59-3.95; p = 0.006).

CONCLUSIONS & INFERENCES

Pathogen-associated molecular patterns stimulation of peripheral blood T cells expressing gut homing marker in IBS compared with controls resulted in an unsuccessful down-regulation of the co-expression of intestinal recruiting/residence phenotype and a state of activation. These findings support an interaction between an innate immune predisposition and microbial triggers, which may unleash or exacerbate IBS.

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

BACKGROUND

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.

AIMS

To determine the usefulness of a method of analysis that employs polar vectors to evaluate the effectiveness of IBS treatments.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

A global perspective on irritable bowel syndrome: a consensus statement of the World Gastroenterology Organisation Summit Task Force on irritable bowel syndrome

Irritable bowel syndrome (IBS) is common in western Europe and North America, and many aspects of its epidemiology, risk factors, and natural history have been described in these regions. Recent data suggest, however, that IBS is also common in the rest of the world and there has been some evidence to suggest some differences in demographics and presenting features between IBS in the west and as it is experienced elsewhere. The World Gastroenterology Organization, therefore, established a Task Force comprising experts on the topic from all parts of the world to examine IBS from a global perspective. IBS does, indeed, seem to be common worldwide though with some significant variations in prevalence rates between regions and countries and there may well be some potentially interesting variations in presenting symptoms and sex distribution. The global map of IBS is far from complete; community-based prevalence data is not available from many areas. Furthermore, while some general trends are evident in terms of IBS impact and demographics, international comparisons are hampered by differences in diagnostic criteria, study location and methodology; several important unanswered questions have been identified that should form the basis for future collaborative research and have the potential to shed light on this challenging disorder.

Lower serum IL-10 is an independent predictor of IBS among volunteers in Mexico

OBJECTIVES

Studies suggest that altered immune activation, manifested by an imbalance in anti- and pro-inflammatory cytokine levels, exists in a subgroup of irritable bowel syndrome (IBS) patients. However, similar studies have not been conducted in Latin populations. The objective of this study was to measure serum levels of interleukin (IL)-10 and tumor necrosis factor (TNF)-α in subjects fulfilling symptom criteria for IBS and controls.

METHODS

Volunteers (n=178) from a university population in Mexico City, participated in the study. Of the sample, 34.8% met Rome II criteria for IBS and 65.2% were designated as controls. Serum cytokines were measured by enzyme-linked immunoabsorbent assay. Analysis of covariance models were used to test main effects between gender, IBS symptoms, and bowel habit subtype to explain the cytokine serum levels. Statistical models were tested using body mass index as a covariate.

RESULTS

IL-10 levels were significantly lower in IBS vs. controls (mean (95% confidence interval): 15.6 (14.8, 16.3) vs. 18.6 (17.9, 19.4) pg/ml, P<0.001), while TNF-α levels were higher in IBS (20.9 (19.1, 23.0) vs. 17.9 (16.7, 19.3) pg/ml, P=0.010). IBS and female gender were independent predictors for IL-10 (P<0.05). In contrast, female gender was an independent predictor for TNF-α. In addition, women with IBS-D had the lowest IL-10 (P<0.001) and highest TNF-α (P=0.021) vs. other subtypes.

CONCLUSIONS

The lower serum IL-10 in our subjects fulfilling IBS Rome II symptom criteria suggests an altered immune regulation. Further studies are needed to elucidate if a lower serum IL-10 may be useful as a biomarker for IBS in the Mexican population, especially for women with IBS-D.

The epidemiology of functional gastrointestinal disorders in Mexico: a population-based study

Aims. The frequency of functional gastrointestinal disorders (FGIDs) in the general population of Mexico is unknown. Methods. To determine the prevalence of FGIDs, associated depression, and health care utilization, a population-based sampling strategy was used to select 500 households in the State of Tlaxcala, in central Mexico. Household interviews were conducted by two trained physicians using the Rome II Modular Questionnaire, a health-care and medication used questionnaire and the CES-D depression scale. Results. The most common FGIDs were IBS: 16.0% (95% CI: 12.9-19.5); functional bloating: 10.8% (8.2-13.9); unspecified functional bowel disorder: 10.6% (8.0-13.6); and functional constipation (FC): 7.4% (5.3-10.1). Uninvestigated heartburn was common: 19.6% (16.2-23.4). All FGIDs were equally prevalent among both genders, except for IBS (P = 0.001), IBS-C (P < 0.001), IBS-A/M (P = 0.049), and FC (P = 0.039) which were more frequent in women. Subjects with FGIDs reported higher frequencies of medical visits: 34.6 versus 16.8%; use of medications: 40.7 versus 21.6%; (both P < 0.001); and reported depression: 26.7 versus 6.7%, (P < 0.001). Conclusion. In this first population-based study of FGIDs in Mexico, heartburn, IBS, functional distension, and FC were common. Only IBS, IBS-C, IBS-A/M, and FC were more frequent in women. Finally, FGIDs in Mexico had an increased burden of health care utilization and depression.

Review article: the treatment of functional abdominal bloating and distension

BACKGROUND

Abdominal bloating and distension are common symptoms in patients with functional gastrointestinal disorders (FGIDs), however, relatively little is known about their treatment.

AIM

To review the treatment trials for abdominal bloating and distension.

METHODS

A literature review in Medline for English-language publications through February 2010 of randomised, controlled treatment trials in adults. Study quality was assessed according to Jadad's score.

RESULTS

Of the 89 studies reviewed, 18% evaluated patients with functional dyspepsia, 61% with irritable bowel syndrome (IBS), 10% with chronic constipation and 10% with other FGIDs. No studies were conducted in patients diagnosed with functional abdominal bloating. The majority of trials investigated the efficacy of prokinetics or probiotics, although studies are heterogeneous with respect to diagnostic criteria and outcome measures. In general, bloating and/or distension were evaluated as secondary endpoints or as individual symptoms as part of a composite score rather than as primary endpoints. A greater proportion of IBS patients with constipation reported improvement in bloating with tegaserod vs. placebo (51% vs. 40%, P<0.0001) and lubiprostone (P<0.001). A greater proportion of nonconstipating IBS patients reported adequate relief of bloating with rifaximin vs. placebo (40% vs. 30%, P<0.001). Bloating was significantly reduced with the probiotics, Bifidobacterium infantis 35624 (1×10(8) dose vs. placebo: -0.71 vs. -0.44, P<0.05) and B. animalis (live vs. heat-killed: -0.56±1.01 vs. -0.31±0.87, P=0.03).

CONCLUSIONS

Prokinetics, lubiprostone, antibiotics and probiotics demonstrate efficacy for the treatment of bloating and/or distension in certain FGIDs, but other agents have either not been studied adequately or have shown conflicting results.

[Guidelines for diagnosis and treatment of constipation in Mexico. A) Epidemiology (meta-analysis of the prevalence), pathophysiology and classification]

BACKGROUND

Constipation is a common problem in the general population and its prevalence is based on the diagnostic criteria, the study population and the research methodology for collecting the data.

OBJECTIVES AND METHODS

To establish the clinical gudelines for diagnosis and treatment of chronic constipation in Mexico we have reviewed the epidemiological factors of constipation and have conducted meta-analysis according to the 3 available community-based studies from our country. In addition, evidence-based recommendations have been provided.

RESULTS

The estimated prevalence of functional constipation in Mexico is 14.4% (95% CI: 12.6-16.6%) according to Rome II and Rome III criteria. Although constipation is present in both genders and all age groups, it is more common among young women with a female to male ratio of 3:1. In our population, 43.6% report using laxatives, teas for stimulating bowel movements or fiber supplements, but only 18.0% did so because they considered themselves as constipated. Also, data from a tertiary referral center in Mexico City suggests that patients with prolonged colonic transit time have lower scores in the physical component of the SF-36 compared to those with chronic constipation and a normal colonic transit time.

CONCLUSIONS

Functional constipation is a very common problem in Mexico affecting mainly young women. Laxatives and other related agents are frequently used and this disorder seems to have a negative impact on quality of life.

From cytokines to toll-like receptors and beyond - current knowledge and future research needs in irritable bowel syndrome

The irritable bowel syndrome (IBS) is a complex disorder in which psychosocial, cultural and biological factors, interact. Recent knowledge in the pathophysiology of IBS, seem to combine issues such as a low grade inflammation or immune activation and dysbiosis that can trigger or exacerbate IBS. On the other hand, stress mediated through the hypothalamic-pituitary-adrenal axis can produce motility abnormalities that can modify the microbiota as well, with the subsequent immune activation in the mucosa and stimulation of nerve terminals, generating symptoms of IBS. Also, we speculate that, stress, dysbiosis or an underlying genetic predisposition, may increase the epithelial permeability leading to a contact between pathogens-associated molecular patterns and toll-like receptors in the deeper layers of the gut, developing a host immunity response and IBS generation. We believe that the role of toll-like receptors in IBS and elucidating the communication processes between the immune and the nervous system, warrant future research.