The current prevalence of irritable bowel syndrome in Asia

Are floating stools associated with specific functional bowel disorders?

BACKGROUND

Functional bowel disorders are recognized as being common, but remain very difficult to diagnose accurately and to differentiate from one another, despite their significant impact on the quality of life of patients.The aim of this study was to evaluate whether the clinical sign of 'floating stools' is associated with psychological disorders, colonic transit time, or other specific bowel disorders as defined by the Rome III diagnostic criteria.

MATERIALS AND METHODS

A total of 1252 consecutive patients, referred for and found to have functional gastrointestinal disorders, filled in a standard clinical questionnaire on the basis of the Rome III diagnostic criteria and were asked to provide information on the presence of floating stools. Overall, 344 of these scored positive for functional bowel disorders and underwent psychometric testing and colonic transit time studies.

RESULTS

Floating stools were reported by 26% of functional bowel disorder patients and 3% of the other functional gastrointestinal disorder patients (P<0.001). The basic demographic characteristics, psychometric evaluation scores, Bristol stool form scales, and total and segmental colonic transit times were not statistically different according to the presence or not of floating stools in these patients. Logistic regression showed that mixed irritable bowel syndrome was the only functional gastrointestinal disorder associated independently with floating stools (P=0.003).

CONCLUSION

Floating stools are a characteristic of patients with mixed irritable bowel syndrome.

Systematic review: dietary fibre and FODMAP-restricted diet in the management of constipation and irritable bowel syndrome

BACKGROUND

Dietary fibre supplements have been advocated for the management of chronic constipation (CC) and irritable bowel syndrome (IBS). Recently, a fermentable oligosaccharide, disaccharide, monosaccharide and polyol (FODMAP) restricted diet has been recommended for IBS.

AIM

To systematically examine recent evidence for dietary interventions with fibre in CC and IBS and FODMAP-restricted diet in IBS, and provide recommendations.

METHODS

We searched PUBMED, MEDLINE, OVID and COCHRANE databases from 2004 to 2014. Published studies in adults with CC and IBS and constipation-predominant IBS (IBS-C) that compared fibre with placebo/alternative and FODMAP-restricted diet with alternative were included.

RESULTS

Of 550 potentially eligible clinical trials on fibre, 11 studies were found and of 23 potentially eligible studies on FODMAPs, six were found. A meta-analysis was not performed due to heterogeneity and methodological quality. Fibre was beneficial in 5/7 studies in CC and 3/3 studies in IBS-C. FODMAP-restricted diet improved overall IBS symptoms in 4/4 and IBS-C symptoms in 1/3 studies and three studies did not meet inclusion criteria. There were significant disparities in subject selection, interventions and outcome assessments in both fibre and FODMAPs studies.

CONCLUSIONS

Fibre supplementation is beneficial in mild to moderate CC and IBS-C, although larger, more rigorous and long-term RCTs are needed (Fair evidence-Level II, Grade B). Although the FODMAP-restricted diet may be effective in short-term management of selected patients with IBS (Fair evidence-Level II, Grade C) and IBS-C (Poor evidence-Level III, Grade C), more rigorous trials are needed to establish long-term efficacy and safety, particularly on colonic health and microbiome.

Prevalence and factors associated with irritable bowel syndrome among university students in Lebanon: Findings from a cross-sectional study

AIM: To describe the bowel habits and the prevalence of irritable bowel syndrome (IBS) and to investigate the influence of health behavior and social factors on IBS prevalence in university students.

METHODS: This cross-sectional study was conducted at five major universities in Greater Beirut and its suburbs, between February and June 2014. Using a convenience sample, a total of 813 students aged 18 years old and above participated in this study. Participants were asked to complete a comprehensive anonymous questionnaire which detailed characteristics on socio-demographic, health-related, and lifestyle factors, as well as IBS. The ROME III criteria were used as a tool to ascertain IBS. A χ² test was used to determine differences between categorical variables; stepwise logistic regression was used to measure the association between IBS and its risk factors.

RESULTS: An overall prevalence of IBS of 20% was recorded among university students. The bivariate analysis showed that females were significantly more likely to report having IBS than males (29.1% vs 18.2%, P < 0.01). Those living at the school dormitory or in a private residence (39.5%) were more likely to have IBS than those living with their families (16.3%) (P < 0.01). The multivariate analysis showed that those who had a relatively high family income level (US$ > 2000) were almost 6 times more likely to report having IBS than their counterparts.

CONCLUSION: This is the first study to describe the nature of IBS among young adults in Lebanon. The prevalence of IBS among university students in our sample was higher than that reported in the West.

Irritable bowel syndrome and the incidence of colorectal neoplasia: a prospective cohort study with community-based screened population in Taiwan

Background:

We aim to report the prevalence of irritable bowel syndrome (IBS) and elucidate the influence of IBS on the incidence of colorectal neoplasm through a community-screening-based, longitudinal follow-up study.

Methods:

We enroled 39 384 community residents aged 40 years or older who had participated in a community-based colorectal cancer-screening programme with an immunochemical faecal occult test since 1999. We followed a cohort that was free of colorectal neoplasm (excluding colorectal neoplasm at baseline) to ascertain the incident colorectal neoplasm through each round of screening and used a nationwide cancer registry. Information on IBS was obtained by linking this screened cohort with population-based health insurance claim data. Other confounding factors were also collected via questionnaire or biochemical tests.

Results:

The overall period prevalence of IBS was 23%, increasing from 14.7% for subjects aged 40–49 years to 43.7% for those aged 70 years and more. After controlling for age, gender and family history of colorectal cancer, screenees who had been diagnosed as having IBS exhibited a significantly elevated level (21% adjusted hazard ratio (HR)=1.21 (95% CI: 1.02–1.42)) of incident colorectal adenoma compared with those who had not been diagnosed with IBS. A similar finding was noted for invasive carcinoma; however, the size of the effect was of borderline statistical significance (adjusted HR=1.20 (95% CI: 0.94–1.53)).

Conclusions:

IBS led to an increased risk for incident colorectal neoplasm.

Advances in the management of constipation-predominant irritable bowel syndrome: the role of linaclotide

Constipation-predominant irritable bowel syndrome (IBS-C) is a commonly prevalent and clinically challenging disorder to treat. Until recently, most therapeutic agents had limited ability to address the complexity of symptoms inherent to the syndrome. The development of linaclotide provides a physiologically sound approach to treatment of the multiple symptoms of IBS-C. Clinical trials demonstrate the efficacy of linaclotide, and a platform to better understand the symptomatology of IBS-C. Based on recent clinical evidence, linaclotide should be considered for patients with IBS-C because it improves abdominal pain and bowel symptoms. In phase III trials, linaclotide met the US Food and Drug Administration responder endpoint with a number needed to treat (NNT) of 5.1-7.9, and European Medicines Agency coprimary endpoints at 12 weeks with a NNT of 4.39-7.69, and at 26 weeks with a NNT of 4.93-5.68. It is safe and effective, with diarrhea reported as the most common adverse effect, which leads to discontinuation of the medication in approximately 5% of patients.

So-eum type as an independent risk factor for irritable bowel syndrome: a population-based study in Korea

OBJECTIVES

It has been hypothesized that Sasang constitutional types (SCTs) have a specific hypoactive organ, which can account for vulnerability to related diseases or symptoms. This study examined the relationship between SCTs and irritable bowel syndrome (IBS).

DESIGN

Cross-sectional study in a population-based cohort study in Korea.

PARTICIPANTS

1362 individuals (705 men and 657 women) who participated in the Korean Genome and Epidemiology Study.

OUTCOME MEASURES

The participants were classified into SCTs by the integrated diagnostic model and asked about symptoms related to IBS using the Rome II criteria.

RESULTS

The prevalence of IBS differed significantly among the SCTs, with 33 (18.3%) of the So-eum (SE) type, 74 (9.9%) of the Tae-eum (TE) type, and 57 (13.2%) of the So-yang (SY) type having IBS. Even after adjustment for possible confounders, the SE type for both sexes continued to show 1.82-fold (95% confidence interval [CI], 1.05-3.16) excess odds of having IBS. Men with SE type had a 2.97 times (95% CI, 1.34-6.58) and a 2.50 times (95% CI, 1.15-5.47) significantly higher odds of having IBS than the TE and SY types, respectively. In analysis for the joint effect of SCT and psychological stress, the multivariate odds ratio of IBS was 3.21 (95% CI, 1.33-7.75) for the SE type and Psychological Well-Being Index-Short Form (PWI-SF) score (<27), and 5.83 (95% CI, 1.80-18.88) for the SE type and PWI-SF (≥27) compared with the TE type and PWI-SF score (<27).

CONCLUSIONS

The SE type of SCT is an independent risk factor for IBS. The findings support the hypothesis that persons with SE type are vulnerable to gastrointestinal diseases.

Association Between SLC6A4 Serotonin Transporter Gene Lainked Polymorphic Region and ADRA2A -1291C>G and Irritable Bowel Syndrome in Korea

Background/Aims

Despite numerous studies on the relation of genetic polymorphisms with irritable bowel syndrome (IBS), the results still remain inconclusive. The aim of this study was to assess the possible association between SLC6A4 serotonin transporter gene linked polymorphic region (5-HTTLPR), ADRA2A −1291C>G, GNB3 825C>T, CCK1R intron 779T>C and TRPV1 945G>C polymorphisms and IBS based on Rome III criteria in Korea.

Methods

Study subjects were prospectively recruited from visitors to Seoul National University Bundang Hospital between July 2009 and January 2014. Ninety-nine IBS patients and 171 healthy controls were enrolled. Polymorphisms of above-mentioned 5 genes were genotyped. Serum serotonin from 101 participants was measured by ELISA and compared according to SLC6A4 5-HTTLPR polymorphisms and IBS subtypes.

Results

Regarding SLC6A4 5-HTTLPR polymorphism, L/L genotype was significantly associated with the total IBS, constipation predominant IBS (IBS-C) and mixture of diarrhea and constipation IBS (IBS-M) (adjusted OR: 4.35, 95% CI: 1.04–16.67; adjusted OR: 11.11, 95% CI: 1.69–50.00 and adjusted OR: 5.56, 95% CI: 1.05–33.33, respectively). Carrying ADRA2A −1291G allele was significantly associated with total IBS and diarrhea predominant IBS (adjusted OR: 3.37, 95% CI: 1.16–9.77 and adjusted OR: 5.64, 95% CI: 1.18–27.01, respectively). IBS-C patients showed reduced level of serum serotonin compared to controls and patients with diarrhea predominant IBS (50.2 ng/mL vs. 69.0 ng/mL and 92.9 ng/mL, P = 0.017 and P = 0.001, respectively).

Conclusions

Genetic polymorphisms of SLC6A4 5-HTTLPR and ADRA2A −1291C>G could be one of the pathophysiological factors of IBS in Korea. Reduced serum serotonin shown in the IBS-C group suggested a role of serotonin in IBS, but large study is needed for confirming genotypic difference in serum serotonin level.

A genetic association study of single nucleotide polymorphisms in GNβ3 and COMT in elderly patients with irritable bowel syndrome

Background

Several polymorphisms have been reported to be associated with irritable bowel syndrome (IBS), including C825T, the single nucleotide polymorphism (SNP), responsible for a truncated G protein β3 subunit (GNβ3), and the Vall158Met substitution in catechol-O-methyltransferase (COMT). We investigated the association between these mutations and the prevalence of IBS in 66 elderly Chinese patients.

Material/Methods

Sixty-six patients (over age 60 years) were diagnosed with IBS according to the Rome III criteria, and divided into 3 groups based on symptom presentation. The groups consisted of 7 patients with constipation, 46 patients with diarrhea, and 13 patients with both or neither symptoms. We enrolled 115 age-matched individuals without IBS as the control group. All patients were evaluated by using the Geriatric Depression Scale, disease progression was recorded, and GNβ3 and COMT were genotyped by PCR.

Results

There was no significant difference in GNβ3 C825T genotype distribution and allele frequency between the 2 groups. In contrast, compared with control subjects, COMT 158Met was significantly more prevalent in the IBS group (P=0.040) and significantly more prevalent in patients with diarrhea (P=0.029). 158Met was also more prevalent in those patients who had experienced symptoms for over 5 years (P=0.022).

Conclusions

In elderly Chinese patients, the 158Met SNP in COMT is associated with IBS pathogenesis, but the GNβ3-C825T SNP is not associated with IBS pathogenesis.

Expression of G protein-coupled estrogen receptor in irritable bowel syndrome and its clinical significance

OBJECTIVES

Estrogen is suggested to participate in pathogenesis of irritable bowel syndrome (IBS), but expression of G protein-coupled estrogen receptor (GPER) in the colon of IBS patients has never been investigated. The aim of this study was to investigate the expression of GPER and classical estrogen receptors in the colon of IBS patients and healthy controls.

METHODS

Colonic biopsies were obtained by endoscopy from patients with IBS (n=46) and healthy subjects (n=13). Expression of GPER, estrogen receptor α (ERα) and estrogen receptor β (ERβ) in mast cells were measured by double-labelling immunofluorescence. Quantification of mRNA expression was performed for GPER, ERα and ERβ by real-time polymerase chain reaction.

RESULTS

Differential distribution of GPER, ERα and ERβ were detected in human colonic mucosa. The expression of GPER in the cytoplasm of mast cells and GPER-positive cells was significantly higher in diarrhea-predominant IBS (D-IBS) patients than that in constipation-predominant IBS (C-IBS, P<0.001) patients and healthy subjects (P=0.005). ERα and ERβ were not detected in majority of mast cells in colonic mucosa and no difference of immunostaining results for ERα and ERβ was found among these three groups. A positive correlation (r=0.451, P=0.011) between GPER-positive cell counts and abdominal pain severity was observed in D-IBS group. Relative mRNA expression of GPER in D-IBS was also higher than that in C-IBS (P=0.018) and healthy subjects (P=0.011).

CONCLUSIONS

The present study, for the first time, demonstrated the expression of GPER in human colonic mucosa and its correlation with abdominal pain severity.

Irritable bowel syndrome: The evolution of multi-dimensional looking and multidisciplinary treatments

Irritable bowel syndrome (IBS) is common in the society. Among the putative pathogeneses, gut dysmotility results in pain and disturbed defecation. The latter is probably caused by the effect of abnormal gut water secretion. The interaction between abnormal gas accumulation, abdominal pain and bloating remains controversial. Visceral hypersensitivity and its modification along with the central transmission are the characteristics of IBS patients. The identification of biologic markers based on genetic polymorphisms is undetermined. Imbalanced gut microbiota may alter epithelial permeability to activate nociceptive sensory pathways which in turn lead to IBS. Certain food constituents may exacerbate bowel symptoms. The impact of adult and childhood abuses on IBS is underestimated. Using the concept of biopsychosocial dysfunction can integrate multidimensional pathogeneses. Antispasmodics plus stool consistency modifiers to treat the major symptoms and defecation are the first-line drug treatment. New drugs targeting receptors governing bowel motility, sensation and secretion can be considered, but clinicians must be aware of their potential serious side effects. Psychiatric drugs and modalities may be the final options for treating intractable subjects. Probiotics of multi-species preparations are safe and worth to be considered for the treatment. Antibiotics are promising but their long-term safety and effectiveness are unknown. Diet therapy including exclusion of certain food constituents is an economic measure. Using relatively safe complementary and alternative medicines (CAMs) may be optional to those patients who failed classical treatment. In conclusion, IBS is a heterogeneous disorder with multidimensional pathogeneses. Personalized medicines with multidisciplinary approaches using different classes of drugs, psychiatric measures, probiotics and antibiotics, dietary therapy, and finally CAMs, can be considered.

Reduced E-cadherin expression is associated with abdominal pain and symptom duration in a study of alternating and diarrhea predominant IBS

BACKGROUND

Increased intestinal permeability and altered expression of tight junction (TJ) proteins may be implicated in the pathogenesis of irritable bowel syndrome (IBS). This study aimed to investigate the expression of adherens junction (AJ) protein E-cadherin and TJ proteins zonula occludens (ZO)-1 and claudin (CLD)-1 and associations with IBS symptoms.

METHODS

Junctional proteins were immunostained in cecal biopsy tissue of Rome II IBS patients (n = 34) comprising both alternating (IBS-A) and diarrhea predominant (IBS-D) subtypes, and controls (n = 12). IBS symptom duration, abdominal pain severity and stool frequency were assessed for IBS patients. Protein expression was determined by immunofluorescence.

KEY RESULTS

E-cadherin and ZO-1 protein expression was significantly lower (p = 0.03 and p = 0.016, respectively) in the cecal surface epithelium of the IBS group comprising both IBS-A and IBS-D subtypes. CLD-1 expression was not significantly altered compared with controls. On subtype analysis, ZO-1 expression was significantly reduced in both IBS-A and IBS-D compared with controls, whereas E-cadherin was reduced only in IBS-A. Lower E-cadherin expression was associated with longer symptoms duration specifically in IBS-A patients (rs = -0.76, p = 0.004). Reduced E-cadherin associated with abdominal pain severity in the overall IBS group (rs = -0.36, p = 0.041), but this association was unrelated to IBS subtype.

CONCLUSIONS & INFERENCES

E-cadherin protein expression in the cecum was significantly lower in IBS-A compared with controls and associated with longstanding symptoms. E-cadherin was further associated with abdominal pain severity in the IBS group overall, but unrelated to IBS subtype. Altered E-cadherin expression may provide novel insights into mechanisms underlying intestinal barrier dysfunction in IBS.

Association study of serotonin transporter SLC6A4 gene with Chinese Han irritable bowel syndrome

Objective

Irritable bowel syndrome (IBS) is a common clinical gastrointestinal dysfunction disorders. 5-sertonon (5-hydroxytryptamine, 5-HT) is a very important neurotransmitter, which is involved in gastrointestinal motion and sensation. Solute carrier family 6 member 4 (SLC6A4) gene encode serotonin transporter (SERT) which function is to rapidly reuptake the most of 5-HT. Therefore, it is needed to explore the association between SLC6A4 gene polymorphisms and IBS.

Methods

119 patients and 238 healthy controls were administrated to detect the SLC6A4 gene polymorphisms including 5-HT-transporter-gene-linked polymorphic region (5-HTTLPR), variable number of tandem repeats (VNTRs) and three selected tag Single Nucleotide Polymorphisms (SNPs) rs1042173, rs3794808, rs2020936 by using polymerase chain reaction (PCR) and TaqMan® SNP Genotyping.

Results

There were significant difference for 5-HTTLPR between IBS and control groups (X2 = 106.168, P<0.0001). In control group, genotypes were mainly L/L (58.4%), however, the genotypes in IBS were S/S (37.8%). The significant difference was shown in D-IBS subjects when compared to the controls (X² = 50.850, P<0.0001) for 5-HTTLPR. For STin2 VNTR, rs1042173, rs3794808, and rs2020936 polymorphisms, there were no any significant differences between IBS and control groups. There were no statistical significantly haplotypes for 5-HTTLPR, VNTRs and the three SNPs between IBS and controls.

Conclusion

The S allele in 5-HTTLPR was a susceptible allele with Chinese Han IBS, but other associations of VNTRs, three selected Tag SNPs and positive haplotype with IBS were not found. It is indicated that much research are needed to study the relationship between other polymorphisms in SLC6A4 gene and IBS.

Effect of korean herbal medicine combined with a probiotic mixture on diarrhea-dominant irritable bowel syndrome: a double-blind, randomized, placebo-controlled trial

Introduction. Although combination therapy with herbal medicine and probiotics is gaining popularity for controlling diarrhea-dominant irritable bowel syndrome (D-IBS) symptoms, few studies have investigated its clinical effects. Materials and Methods. Fifty-three patients with D-IBS were randomly allocated into 1 of the following 4 groups: herbal medicine (Gwakhyangjeonggisan; GJS) plus probiotics (Duolac7S; DUO), GJS plus placebo DUO, placebo GJS plus DUO, and placebo GJS plus placebo DUO. The study period consisted of a 2-week run-in, 8 weeks of administration, and 2 weeks of follow-up. The primary outcomes were weekly adequate relief (AR) of overall IBS symptoms and the proportion of responders (PR) during the administration period. The secondary outcomes included individual IBS symptoms, stool assessment, and quality of life. Changes of intestinal microbiota and intestinal permeability were also analyzed. Results and Discussion. Weekly AR was not different among the 4 groups throughout the treatment period. However, the 3 treatment groups exhibited significant improvements in PR compared to the findings in the placebo group. In the intestinal microbiota assessment, herbal medicine and probiotics synergistically increased beneficial bacteria counts. Conclusion. Combination therapy with herbal medicine and probiotics appears to relieve overall IBS symptoms by synergistically increasing beneficial intestinal microbe counts.

Comparison of Manning, Rome I, II, and III, and Asian diagnostic criteria: report of the Multicentric Indian Irritable Bowel Syndrome (MIIBS) study

BACKGROUND

Attempts to diagnose and subtype irritable bowel syndrome (IBS) by symptom-based criteria have limitations, as these are developed in the West and might not be applicable in other populations.

OBJECTIVES

This study aimed to compare different criteria for diagnosing and subtyping of IBS in India.

METHOD

Manning's and the Rome I, II, and III criteria as well as the Asian criteria were applied to 1,618 patients (from 17 centers in India) with chronic lower gastrointestinal (GI) symptoms with no alarm features and negative investigations.

RESULTS

Of 1,618 patients (aged 37.5 [SD 12.6] years; 71.2% male), 1,476 (91.2%), 1,098 (67.9%), 649 (40.1%), 849 (52.5%), and 1,206 (74.5%) fulfilled Manning's, Rome I, II, and III, and the Asian criteria, respectively. The most common reason for not fulfilling the criteria was absence of the following symptoms: "more frequent stools with onset of pain," "loose stool with onset of pain," "relief of pain with passage of stool," "other abdominal discomfort/bloating," and, in a minority, not meeting the duration criterion of 3 months/12 weeks. By stool frequency, constipation-predominant IBS (<3 stools/week) was diagnosed in 319 (19.7%), diarrhea-predominant IBS (>3 stools/day) in 43 (2.7%), and unclassified in 1,256 (77.6%). By Bristol stool form, constipation, diarrhea, and unclassified were diagnosed in 655 (40.5%), 709 (43.8%), and 254 (15.7%) patients, respectively. By their own perception, 462 (28.6%), 541 (33.4%), and 452 (27.9%) patients reported constipation-predominant, diarrhea-predominant, and alternating types, respectively.

CONCLUSION

By Manning's and the Asian criteria, a diagnosis of IBS was made frequently among Indian patients with chronic functional lower GI symptoms with no alarm features; the Rome II criteria gave the lowest yield. By the stool frequency criteria, a majority of patients had unclassified pattern, unlike by the stool form and patients' perception of their symptoms.

Bloating and distention in irritable bowel syndrome: the role of gas production and visceral sensation after lactose ingestion in a population with lactase deficiency

OBJECTIVES

Bloating and distention are often attributed to dietary factors by patients with irritable bowel syndrome (IBS). This study examined the effects of gas production and visceral hypersensitivity on digestive symptoms after lactose ingestion in a population with lactase deficiency.

METHODS

IBS patients (n=277) and healthy controls (HCs, n=64) underwent a 20-g lactose hydrogen breath test (LHBT) with evaluation of hydrogen gas production and lactose intolerance (LI) symptoms. Abdominal distention (199 IBS, 40 HCs) was measured during LHBT. Rectal sensitivity (74 IBS, 64 HCs) was assessed by barostat studies.

RESULTS

Hydrogen production and distention were similar in IBS patients and HCs during LHBT; however, LI was more frequent in IBS (53.8 vs. 28.1%, P<0.001), especially bloating (39.0% vs. 14.1%, P<0.001) and borborygmi (39.0 vs. 21.9%, P=0.010). Only 59.0% of patients with bloating had distention. No correlation was observed between girth increment and bloating (P=0.585). IBS patients had lower rectal sensory thresholds (P=0.001). Multivariate analysis indicated that hydrogen production increased bloating (odds ratio (OR) 2.19, 95% confidence interval (CI) 1.09-4.39, P=0.028) and borborygmi (OR 12.37, 95% CI 3.34-45.83, P<0.001) but not distention (P=0.673). Visceral hypersensitivity was associated with bloating (OR 6.61, 95% CI 1.75-25.00, P=0.005) and total symptom score (OR 3.78, 95% CI 1.30-10.99, P=0.014).

CONCLUSIONS

Gas production and visceral hypersensitivity both contribute to digestive symptoms, especially bloating and borborygmi, in IBS patients after lactose ingestion. Objective abdominal distention is not correlated with subjective bloating.

Defecation frequency and stool form in a coastal eastern Indian population

Background/Aims

Data on normal stool form and frequency, which are important for defining constipation, are scanty; hence, we studied these in an eastern Indian population.

Methods

One thousand and two hundred apparently healthy asymptomatic subjects were evaluated for predominant stool form (Bristol chart with descriptor) and frequency. Data on demographic and life-style (diet and physical activity) were collected.

Results

Of 1,200 subjects (age 42 ± 14.5 years, 711, 59% male), most passed predominantly Bristol type IV stool (699 [58.2%]; other forms were: type I (23 [1.9%]), type II (38 [3.2%]), type III (99 [8.2%]), type V (73 [6%]), type VI (177 [14.7%]), type VII (7 [0.6%]) and an irregular combination (84 [7%]). Weekly stool frequency was 12.1 ± 4.7 (median 14, range 2-42). Less than 3 stools/week was noted in 32/1,200 (2.6%). Female subjects (n = 489) passed stools less frequently than males (n = 711) (11.1 ± 5.6/week vs. 12.8 ± 3.8/week, P < 0.001) and tended to pass harder forms (type I: 17, type II: 20, type III: 39 vs. 6, 18 and 60, respectively, P = 0.061). Vegetarians (n = 252) and physically active (n = 379) subjects tended to pass stool more frequently than occasional (n = 553) and regular non-vegetarian (n = 395) (11.8 ± 4.5 and 12.8 ± 4.7 vs. 11.3 ± 4.7; P < 0.05) and sedentary (n = 464) and intermediately active (n = 357) subjects (13.4 ± 4.0 and 12.3 ± 4.5 vs. 10.9 ± 5.1, P = 0.080) in different age groups, respectively. Older age was associated with less frequent stool, particularly among female population. Female gender and age > 35 years were significant on multivariate analysis.

Conclusions

Median stool frequency in the studied population was 14/week (range 2-42) and predominant form was Bristol type IV. Older age was associated with lesser stool frequency, particularly among female subjects.

Irritable bowel syndrome and migraine: bystanders or partners?

Irritable bowel syndrome (IBS) and migraine are distinct clinical disorders. Apart from the characteristics of chronic and recurrent pain in nature, these pain-related disorders apparently share many similarities. For example, IBS is female predominant with community prevalence about 5-10%, whereas that of migraine is 1-3% also showing female predominance. They are often associated with many somatic and psychiatric comorbidities in terms of fibromyaglia, chronic fatigue syndrome, interstitial cystitis, insomnia and depression etc., even the IBS subjects may have coexisted migraine with an estimated odds ratio of 2.66. They similarly reduce the quality of life of victims leading to the social, medical and economic burdens. Their pathogeneses have been somewhat addressed in relation to biopsychosocial dysfunction, heredity, genetic polymorphism, central/visceral hypersensitivity, somatic/cutaneous allodynia, neurolimbic pain network, gonadal hormones and abuses etc. Both disorders are diagnosed according to the symptomatically based criteria. Multidisciplinary managements such as receptor target new drugs, melantonin, antispasmodics, and psychological drugs and measures, complementary and alternatives etc. are recommended to treat them although the used agents may not be necessarily the same. Finally, the prognosis of IBS is pretty good, whereas that of migraine is less fair since suicide attempt and stroke are at risk. In conclusion, both distinct chronic pain disorders to share many similarities among various aspects probably suggest that they may locate within the same spectrum of a pain-centered disorder such as central sensitization syndromes. The true pathogenesis to involve these disorders remains to be clarified in the future.

Prevalence and presentation of lactose intolerance and effects on dairy product intake in healthy subjects and patients with irritable bowel syndrome

BACKGROUND & AIMS

The effects of lactase deficiency on digestive symptoms and diet in patients with irritable bowel syndrome (IBS) have not been well defined. We assessed lactose absorption and tolerance and the intake of dairy products in healthy volunteers (controls) and patients with diarrhea-predominant IBS (D-IBS).

METHODS

Sixty patients diagnosed with D-IBS at the Sir Run Run Shaw Hospital, Hangzhou, China and 60 controls were given hydrogen breath tests to detect malabsorption and intolerance after administration of 10, 20, and 40 g lactose in random order 7-14 days apart; participants and researchers were blinded to the dose. We assessed associations between the results and self-reported lactose intolerance (LI).

RESULTS

Malabsorption of 40 g lactose was observed in 93% of controls and 92% of patients with D-IBS. Fewer controls than patients with D-IBS were intolerant to 10 g lactose (3% vs 18%; odds ratio [OR], 6.51; 95% confidence interval [CI], 1.38-30.8; P = .008), 20 g lactose (22% vs 47%; OR, 3.16; 95% CI, 1.43-7.02; P = .004), and 40 g lactose (68% vs 85%; OR, 2.63; 95% CI, 1.08-6.42; P = .03). H(2) excretion was associated with symptom score (P = .001). Patients with D-IBS self-reported LI more frequently than controls (63% vs 22%; OR, 6.25; 95% CI, 2.78-14.0; P < .001) and ate fewer dairy products (P = .040). However, self-reported LI did not correlate with results from hydrogen breath tests.

CONCLUSIONS

The risk of LI is related to the dose of lactose ingested and intestinal gas production and is increased in patients with D-IBS. Self-reported LI, but not objective results from hydrogen breath tests, was associated with avoidance of dairy products.

Mental, physical, dietary, and nutritional effects on irritable bowel syndrome in young Japanese women

OBJECTIVE

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder. The pathogenesis of IBS is multifactorial. The aim of this study was to investigate the prevalence of IBS using the Rome III criteria in young Japanese women and to assess the effects of mental, physical, dietary and nutritional factors on IBS.

METHODS

In this cross-sectional study, data obtained from self-administered questionnaires, including age, height, weight, lifestyle, food habits, anxiety and depressive states and IBS-related symptoms, were analyzed in 245 participants. An established semiquantitative questionnaire available for clinical investigation (FFQg) was used to obtain a detailed assessment of food intake and the physical activity levels.

RESULTS

The prevalence of IBS was 12.0%. Of the IBS participants, constipation-predominant IBS (25.0%) was more prevalent than the diarrhea-predominant subtype (17.9%). The IBS participants had lower body mass indices, consumed less eggs and milk and were more physically active than the non-IBS participants. In addition, an anxiety state was more common in the IBS participants. Those who hesitated with evacuation of stool and who thought that there is an association between abdominal symptoms, such as constipation and diarrhea, and menstruation were more predominant among the IBS participants. The percentage of individuals who reported often rushing to the toilet within the past year and experiencing borborygmus (rumbling stomach) was greater among the IBS participants. A logistic regression analysis revealed that milk intake was an independent predictor of IBS.

CONCLUSION

The prevalence of IBS observed in this study was similar to that reported in previous studies conducted in Japan and other countries. Mental, physical, dietary and nutritional factors have an impact on IBS.

Influence of insomnia and insomnia-related psychological factors on symptoms of female patients with irritable bowel syndrome

AIM: To investigate the influence of insomnia and insomnia-related psychological factors on the symptoms of female patients with irritable bowel syndrome (IBS).

METHODS: Two hundred and forty-five adult female outpatients with IBS who were treated at the Department of Gastroenterology of the First Affiliated Hospital of Nanjing Medical University were included in this study. A questionnaire survey was conducted using a demographic information questionnaire, a symptom questionnaire, athens insomnia scale (AIS), self-rating anxiety scale (SAS), and self-rating depression scale (SDS). According to AIS scores, female patients with IBS were divided into insomnia group and non-insomnia group. The influence of insomnia on typical symptoms, somatic symptoms and psychological symptoms of IBS, and the relationship between psychological factors and IBS were analyzed.

RESULTS: The insomnia and non-insomnia groups differed significantly in their rating of abdominal pain/discomfort in terms of severity and duration (P < 0.05), but there was no difference in attack frequency between the two groups. The incidence of somatic symptoms, scores of SAS and SDS, and scores of SAS' and SDS' (sleep-related entries were removed) were all significantly higher in the insomnia group than in the non-insomnia group (all P < 0.01). Severity, attack frequency and duration of abdominal pain/discomfort were all positively correlated with SAS and SDS scores (all P < 0.05).

CONCLUSION: Insomnia and insomnia-related psychological factors (anxiety, depression) can aggravate the symptoms of female patients with IBS.

Sex differences in the symptoms and psychological factors that influence quality of life in patients with irritable bowel syndrome

OBJECTIVE

To investigate the relationship between gender and symptomatology, psychological factors, and quality of life (QOL) in irritable bowel syndrome (IBS).

METHODS

The diagnosis of IBS was made on the basis of the Rome III Criteria. A physician obtained demographic and symptom data, Zung Self-Rated Anxiety and Depression Scale scores (SAS/SDS), and IBS-specific quality-of-life ratings (IBS-QOL).

RESULTS

Of the 4015 patients approached, 452 patients were diagnosed with IBS. Age ranged from 14 to 79 years (44.05 ± 14.89 years) and the male to female ratio was 1 : 1.3. The gender composition between the four IBS subtypes differed significantly (P<0.01). Male and female patients differed in their rating of abdominal pain/discomfort in terms of severity and time (P<0.01). Groups did not differ with regard to attack frequency. Female patients more frequently reported headache, dizziness, backache, muscular soreness, inappetence, insomnia, and fatigue (P<0.01). In comparison with men, anxiety and depression scores were significantly higher in women (P<0.01). Severity, duration, and frequency of abdominal pain/discomfort did not correlate with IBS-QOL scores. Insomnia/fatigue was negatively correlated with IBS-QOL scores (P<0.01). SAS and SDS scores were negatively correlated with IBS-QOL (total score and each subscale; P<0.01).

CONCLUSION

There are significant gender differences in the symptoms, psychological rating, and QOL scores in IBS. Somatic symptoms, anxiety, and depression all contribute to the negative impact of IBS. Our findings suggest that gender differences should be recognized in IBS treatment.

The effect of a multispecies probiotic mixture on the symptoms and fecal microbiota in diarrhea-dominant irritable bowel syndrome: a randomized, double-blind, placebo-controlled trial

BACKGROUND

The clinical effect of probiotics on irritable bowel syndrome (IBS) is still controversial.

AIMS

We aimed to evaluate the effects of a probiotic mixture on IBS symptoms and the composition of fecal microbiota in patients with diarrhea-dominant IBS (D-IBS).

METHODS

Fifty patients with D-IBS were randomized into placebo or probiotic mixture (Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus rhamnosus, Bifidobacterium breve, Bifidobacterium lactis, Bifidobacterium longum, and Streptococcus thermophilus 1.0×10 CFU) groups. Treatment was taken daily for 8 weeks. The primary outcome was adequate relief (AR) of overall IBS symptoms, which was assessed weekly for 10 weeks. A responder was defined as a patient who experienced AR for at least half of the 10-week study period. Secondary outcomes included the effects on individual symptoms, stool parameters, and IBS quality of life. The fecal flora compositions were analyzed by polymerase chain reaction denaturing gradient gel electrophoresis (DGGE).

RESULTS

The proportion of AR was consistently higher in the probiotics group than in the placebo group throughout the 10-week period (P<0.05). The proportion of responders was significantly higher in the probiotics group than in the placebo group (48% vs. 12%, P=0.01). Stool consistency improved significantly in the probiotics group compared with the placebo group. Percent changes in individual symptom scores were similar in the 2 groups, but IBS quality of life improvement tended to be higher in the probiotics group. Comparison of denaturing gradient gel electrophoresis profiles of fecal flora showed that the concordance rate between bacterial compositions before and after treatment was significantly higher in the probiotics group than in the placebo group (69.5% vs. 56.5%, P=0.005).

CONCLUSIONS

The probiotic mixture was effective in providing AR of overall IBS symptoms and improvement of stool consistency in D-IBS patients, although it had no significant effect on individual symptoms. The therapeutic effect of probiotics is associated with the stabilization of intestinal microbiota.

Evaluation of health related quality of life in irritable bowel syndrome patients

Background

Quality of life (QOL) is an important measure in the management of Irritable Bowel Syndrome (IBS). Controversy exists in the findings of studies evaluating QOL in IBS subtypes, and little is known about this issue in Iranian patients. Determination of the factors affecting QOL in IBS patients may influence treatment outcomes. The aims of this study are to: 1) compare QOL between subtypes in a sample of Iranian IBS patients, 2) determine the factors associated with QOL in IBS.

Methods

This cross sectional study included two hundred and fifty IBS patients with the mean age (± standard deviation) of 31.62 (± 11.93) years that were referred to outpatient gastroenterology clinic. IBS patients were diagnosed based on Rome-3 criteria by a gastroenterologist, and then they were categorized into three subtypes according to the predominant type of bowel habit. The "QOL specific for IBS", "Stait-trait anxiety inventory", and "Beck depression inventory-2" questioners were used to evaluate QOL, anxiety, and depression symptoms, respectively.

Results

The mean QOL scores in IBS mixed subtype (71.7 ± 25.57), constipation predominant subtype (80.28 ± 25.57), and diarrhea predominant subtype (76.43 ± 19.13) were not different. (P value: 0.05) In multivariate linear regression analysis, anxiety symptom scores were inversely correlated with QOL scores. [Standardized beta: -0.43, (95% confidence interval: -0.70, -0.39), P value: < 0.01]

Conclusion

It seems reasonable to manage anxiety symptoms properly in IBS patients since this might increase their QOL.

Stress-induced visceral analgesia assessed non-invasively in rats is enhanced by prebiotic diet

AIM

To investigate the influence of repeated water avoidance stress (rWAS) on the visceromotor response (VMR) to colorectal distension (CRD) and the modulation of the response by a prebiotic diet in rats using a novel surgery-free method of solid-state manometry.

METHODS

Male Wistar rats fed a standard diet with or without 4% enzyme-treated rice fiber (ERF) for 5 wk were subjected to rWAS (1 h daily x 10 d) or no stress. The VMR to graded phasic CRD was assessed by intraluminal colonic pressure recording on days 0 (baseline), 1 and 10 (45 min) and 11 (24 h) after rWAS and expressed as percentage change from baseline. Cecal content of short chain fatty acids and distal colonic histology were assessed on day 11.

RESULTS

WAS on day 1 reduced the VMR to CRD at 40 and 60 mmHg similarly by 28.9% ± 6.6% in both diet groups. On day 10, rWAS-induced reduction of VMR occurred only at 40 mmHg in the standard diet group (36.2% ± 17.8%) while in the ERF group VMR was lowered at 20, 40 and 60 mmHg by 64.9% ± 20.9%, 49.3% ± 11.6% and 38.9% ± 7.3% respectively. The visceral analgesia was still observed on day 11 in ERF- but not in standard diet-fed rats. By contrast the non-stressed groups (standard or ERF diet) exhibited no changes in VMR to CRD. In standard diet-fed rats, rWAS induced mild colonic histological changes that were absent in ERF-fed rats exposed to stress compared to non-stressed rats. The reduction of cecal content of isobutyrate and total butyrate, but not butyrate alone, was correlated with lower visceral pain response. Additionally, ERF diet increased rWAS-induced defecation by 26% and 75% during the first 0-15 min and last 15-60 min, respectively, compared to standard diet, and reduced rats' body weight gain by 1.3 fold independently of their stress status.

CONCLUSION

These data provide the first evidence of psychological stress-related visceral analgesia in rats that was enhanced by chronic intake of ERF prebiotic.

Gender Role in Irritable Bowel Syndrome: A Comparison of Irritable Bowel Syndrome Module (ROME III) Between Male and Female Patients

BACKGROUND/AIMS

Irritable bowel syndrome (IBS) is a widespread chronic health condition which is significantly more prevalent in women. We conducted a gender difference analysis by comparing findings of men and women to determine whether any significant differences exist or not.

METHODS

This single-center study was conducted in Tehran, Iran during 2009-2010. IBS was diagnosed on the basis of Rome III criteria. A simple "10 point" objective questionnaire was used.

RESULTS

A total number of 144 IBS patients including 44 (30.6%) males and 100 (69.4%) females with the mean age of 37.50 ± 11.50 years, were assessed. The only differently observed symptom was nausea which was significantly more prevalent in females (49% vs 18.2%, P < 0.001). The commonest subtype of IBS in male patients was diarrhea predominant IBS (38.6%); while, constipation predominant IBS was the most frequent type among females (38%). Moreover, the frequency of loose, mushy or watery stools within the last 3 months was significantly higher among males (2.11 ± 1.67 vs 1.37 ± 1.50, P = 0.009).

CONCLUSIONS

We report that gender is important in IBS. Although qualitative comparison of different subtypes of IBS between male and female failed to meet the statistically significant level, the answers to the corresponding questions of ROME III IBS module suggest the higher prevalence of bowel movements and looser stool in males. Moreover, nausea was reported more often by females.

Are Food Constituents Relevant to the Irritable Bowel Syndrome in Young Adults? - A Rome III Based Prevalence Study of the Korean Medical Students

Background/Aims

Irritable bowel syndrome (IBS) is prevalent in general population. This study investigates the prevalence of IBS in medical college students in Korea as well as the influence of dietary habits and nutritional intake on IBS.

Methods

This study is a cross-sectional study of 319 students (239 males and 80 females, age 22.3 ± 2.5 years) from the 6 grade levels of the Medical College in Korea. All students filled out a self-reported questionnaire for ROME III criteria. They also completed a questionnaire to validate dietary habits and food frequency in Korean.

Results

The overall prevalence of IBS was 29.2% without correlation to age, body mass index and grade level in Medical School. However, the prevalence was significantly higher in females than males (33/80 vs 60/239, P = 0.007). There were no significant differences between the IBS-group and the non-IBS group in aspect of nutrition. Not only the diet habits, but also the daily nutritional intake, and even the breakdown into the 12 micronutrients, yielded no significant differences between the 2 groups.

Conclusions

Twenty-nine percent of the medical college students have IBS with a greater prevalence in females. The dietary habits and nutritional intake of the students might not be associated with IBS.

The clinical significances of irritable bowel syndrome in Taiwan

BACKGROUND AND AIM

According to the Rome III definition, irritable bowel syndrome (IBS) has been a biopsychosocial dysfunction. We tried to know whether the IBS clinical manifestations were comparable to other countries.

METHOD

We have reviewed the IBS publications in Taiwan, thus its clinical significances are summarized and compared to others.

RESULTS

Among a selected population of paid physical checkup, the Rome I & II criteria defined prevalences were 17.5% and 22.1%, respectively without an observed female predominance. However, female was a factor leading to constipation predominant IBS (C-IBS). Taiwan IBS patients did excessively consume society resource in terms of physician visits and absenteeism. They also had more chance of cholecystectomy, whereas normal appendix was often found in case of appendectomy. Overlapping extra-colonic manifestations, e.g. dyspepsia and lower urinary tract symptoms were common. Helicobacter pylori infection and female gender were closely related to the coexisted dyspepsia. Various psychiatric disturbances were also confirmed here. Intestinal transit correlated well with bowel symptoms, e.g. slow in constipation but fast in diarrhea. Diminished cholinergic activity was observed among the C-IBS patients. Various agents including mebeverine, pinaverium, peppermint oil, smectitie and tegarserod did somewhat improve IBS symptoms. Unfortunately, the IBS knowledge was not well understood among the medical professionals.

CONCLUSIONS

IBS is common in Taiwan, its impacts on the society are similarly observed while female gender often results in severe impacts. Disordered motility and cholinergic nervous system are likely some of its pathogeneses. Current recommended treatments are effectively demonstrated.