Irritable bowel syndrome is more common in women regardless of the menstrual phase: a Rome II-based survey

Are patients with polycystic ovary syndrome more prone to irritable bowel syndrome?

BACKGROUND

Polycystic ovary syndrome (PCOS) encompasses endocrine, reproductive and metabolic disturbances. Abdominal pain and bowel movement disturbances are common complaints of PCOS patients. It remains uncertain whether the characteristic features of PCOS are associated with an increased incidence of irritable bowel syndrome (IBS).

METHODS

In the study, 133 patients with PCOS diagnosed according to international evidence-based guidelines and 72 age- and BMI-matched eumenorrheic controls were enrolled. Anthropometric measurements and biochemical and hormonal characteristics were collected. The Rome IV criteria were used for IBS diagnosis. Quality of life (QoL) and depressive symptoms were also assessed.

RESULTS

IBS symptom prevalence in PCOS was not significantly different than in controls. Hyperandrogenism and simple and visceral obesity did not appear to affect IBS prevalence in PCOS. There were no anthropometric, hormonal or biochemical differences between IBS-PCOS and non-IBS-PCOS patients, apart from IBS-PCOS patients being slightly older and having lower thyroid-stimulating hormone. Metabolic syndrome (MS) prevalence was higher in IBS-PCOS than non-IBS-PCOS. QoL appears to be significantly lower in IBS-PCOS compared to PCOS-only patients. The occurrence of depression was higher in IBS-PCOS vs non-IBS-PCOS patients. At least one alarm symptom was reported by 87.5% of IBS-PCOS; overall, this group experienced more alarm symptoms than the IBS-only group.

CONCLUSIONS

Since a link between PCOS and IBS comorbidity and increased MS prevalence was noted, patients presenting with both conditions may benefit from early MS diagnostics and management. The high incidence of alarm symptoms in PCOS women in this study highlights the need for differential diagnosis of organic diseases that could mimic IBS symptoms.

The relationship between meal regularity with Irritable Bowel Syndrome (IBS) in adults

BACKGROUND

The irregular meal pattern and meal-skipping might be related to irritable bowel syndrome (IBS), however, findings of previous investigations are contradictory. We aimed to examine the relation of meal regularity with IBS in Iranian adult population.

METHODS

Data on 4599 adults who worked in 50 different health centers were used in this cross-sectional study. Dietary habits were measured using a pretested questionnaire. IBS identification was performed through the use of a modified version of Rome III questionnaire.

RESULTS

IBS was prevalent among 18.6% of men and 24.1% of women. After adjustment for potential confounders, those with regular meal pattern, in comparison to those with irregular meals, had 40% lower odds for IBS (OR:0.60, 95%CI: 0.41-0.87). Individuals with regular meals had also 82 lower risk for IBS-Mixed, in comparison to those who had irregular meals (OR:0.18, 0.95%CI: 0.08-0.43). Stratified analysis by gender revealed that women with regular meals, compared with those who did not, had 44% lower risk for IBS (OR: 0.56, 0.95%CI: 0.34-0.91). Normal-weight individuals who had regular meal pattern, compared to those who did not, had 63% lower risks for IBS (OR:0.37, 95%CI: 0.22-0.64). Furthermore, subjects who had regular meal pattern had 53% lower risk for severe symptoms of IBS (OR:0.47, 95%CI: 0.30-0.71).

CONCLUSION

We found that participants with regular meal pattern had reduced odds of IBS, IBS-Mixed and the syndrome severity. Meal regularity was also linked to reduced IBS prevalence in women, and in normal-weight individuals. More prospective studies are needed to affirm these associations.

Gastrointestinal symptoms in HIV-positive kidney transplant candidates and recipients from an HIV-positive donor

Gastrointestinal symptoms (GIS) are common in kidney transplant candidates and recipients and may be worsened by HIV. Objective: To determine the frequency and severity of GIS in HIV-positive kidney transplant recipients from HIV-positive donors, and those waiting to receive one. A GIS rating scale (GSRS) was completed by 76 participants at baseline and at 6 months. GIS frequency was defined as having at least one symptom (GSRS > 1). Severity was indicated by the GSRS score. Transplant candidates: GIS frequency was 88.9% and 86.3% at baseline and 6 months respectively. Indigestion was the most frequent (79.6% and 66.7% at baseline and 6 months), and severe GIS (GSRS 2.3). Women reported global mean (p = 0.030) severity significantly more than men. Transplant recipients: GIS frequency was 95.2% and 76.2% at baseline and 6 months respectively. At both assessment points, indigestion occurred most frequently (85.7% and 61.9% respectively). Highest GSRS was reported for indigestion at baseline (2.33) and at 6 months (1.33). Waist circumference (WC) was positively associated with the severity of constipation GSRS. GIS are common in both groups, especially indigestions. WC in transplant recipients should be monitored.

Irritable Bowel Syndrome and Neurological Deficiencies: Is There A Relationship? The Possible Relevance of the Oxidative Stress Status

Background: Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders, exhibiting complex and controversial pathological features. Both oxidative stress and inflammation-related reactive oxygen species production may be involved in IBS pathological development. Thus, we focused on several aspects regarding the causes of oxidative stress occurrence in IBS. Additionally, in the molecular context of oxidative changes, we tried to discuss these possible neurological implications in IBS. Methods: The literature search included the main available databases (e.g., ScienceDirect, Pubmed/Medline, Embase, and Google Scholar). Articles in the English language were taken into consideration. Our screening was conducted based on several words such as “irritable bowel syndrome”, “gut brain axis”, “oxidative stress”, “neuroendocrine”, and combinations. Results: While no consistent evidence suggests clear pathway mechanisms, it seems that the inflammatory response may also be relevant in IBS. The mild implication of oxidative stress in IBS has been described through clinical studies and some animal models, revealing changes in the main markers such as antioxidant status and peroxidation markers. Moreover, it seems that the neurological structures involved in the brain-gut axis may be affected in IBS rather than the local gut tissue and functionality. Due to a gut-brain axis bidirectional communication error, a correlation between neurological impairment, emotional over-responsiveness, mild inflammatory patterns, and oxidative stress can be suggested. Conclusions: Therefore, there is a possible correlation between neurological impairment, emotional over-responsiveness, mild inflammatory patterns, and oxidative stress that are not followed by tissue destruction in IBS patients. Moreover, it is not yet clear whether oxidative stress, inflammation, or neurological impairments are key determinants or in which way these three interact in IBS pathology. However, the conditions in which oxidative imbalances occur may be an interesting research lead in order to find possible explanations for IBS development.

Epidemiology of irritable bowel syndrome and its associated factors in Saudi undergraduate students

BACKGROUND/AIM

Irritable bowel syndrome (IBS) is common among undergraduate students and is associated with several modifiable risk factors. The present study aimed to explore the epidemiology of IBS in Saudi undergraduate students.

MATERIALS AND METHODS

A cross-sectional study was carried out from February 2018 to June 2018. A total of 767 undergraduate students from all regions of Saudi Arabia completed an online self-administered questionnaire. IBS symptoms were assessed using the Rome IV diagnostic criteria.

RESULTS

The mean age was 21.88 years (range 18-29); 56.1% of the study population were females and 50.1% were from the central region of Saudi Arabia. Students of medical colleges represented 30.2% of the sample. The overall prevalence of IBS was 15.8%. Significant independent risk factors for IBS were female sex (OR = 3.738; 95% CI = 2.093, 6.673), being a student in a medical college (OR = 7.216; 95% CI = 4.438, 11.733), living in a rented apartment (OR = 6.752; 95% CI = 2.586, 17.627), living on campus (OR = 6.563; 95% CI = 2.138, 20.145), poor sleep quality (OR = 3.156; 95% CI = 1.850, 5.385), exercise (OR = 0.394; 95% CI = 0.193, 0.803), smoking (OR = 5.256; 95% CI = 2.841, 9.724), family history of IBS (OR = 1.641; 95% CI = 1.012, 2.661), and emotional stress (OR = 2.184; 95% CI = 1.375, 3.469).

CONCLUSION

Overall, 15.8% of participants in this study met the Rome IV criteria for IBS diagnosis. IBS was associated with several lifestyle factors, as well as family history and emotional stress.

Irritable Bowel Syndrome between Molecular Approach and Clinical Expertise-Searching for Gap Fillers in the Oxidative Stress Way of Thinking

Irritable bowel syndrome (IBS) remains to date an intriguing functional gastrointestinal disorder. Recent studies described a multitude of exogenous factors that work together in IBS, gradually impairing intestinal lining cellular metabolism, including oxidative status balance, with or without a genetic background. Although the current biomarkers support the differentiation between IBS subtypes and other functional gastrointestinal disorder, they are mostly non-specific, referring to clinical, biochemical, and inflammatory imbalances. Since IBS could be also the result of deficient signaling pathways involving both gastrointestinal secretion and neuro-vegetative stimulation, IBS makes no exception from the oxidative hypothesis in the pathological mechanisms. Regarding the oxidative stress implication in IBS, the previous research efforts showed controversial results, with some animal models and patient studies reporting clear oxidative imbalance both on systemic and local levels, but still with no concrete evidence to point to a direct correlation between oxidative stress and IBS. Additionally, it seems that a major role could be also attributed to gut microbiota and their ability to shape our bodies and behaviors. Moreover, the genetic features study in IBS patients showed that several genetic similarities point to a possible correlation of IBS with affective spectrum disorders. Thus, we focus here the discussion on the assumption that IBS could in fact be more likely a stress-related disorder rather than a gastrointestinal one.

The effect of 'Zesy002' kiwifruit (Actinidia chinensis var. chinensis) on gut health function: a randomised cross-over clinical trial

Functional gastrointestinal disorders including constipation affect up to 14 % of the world's population. Treatment is difficult and challenging resulting in a need for alternative safe and effective therapies. The present study investigated whether daily consumption of three gold-fleshed kiwifruit could alleviate constipation and improve gastrointestinal discomfort in mildly constipated individuals with and without pain. A total of thirty-two participants were enrolled in a 16-week randomised, single-blind, crossover study. Participants received either three 'Zesy002' kiwifruit or 14·75 g Metamucil® (5 g dietary fibre/d (a positive control)) for 4 weeks each with a 4-week washout between treatments. A 2-week washout period was included at the beginning and end of the study. Daily bowel habit diaries were kept throughout the study. The primary outcome measure was differences in the number of complete spontaneous bowel movements (CSBM). Secondary outcome measures were bowel movement frequency and stool form as well as digestive symptoms and comfort. The number of CSBM per week was significantly greater during daily consumption of three kiwifruit compared with the baseline (6·3 v. 3·3; P < 0·05) and the Metamucil® treatment (6·3 v. 4·5; P < 0·05). Stool consistency was also improved, with kiwifruit producing softer stools and less straining (P < 0·05). Gastrointestinal discomfort was also improved compared with baseline for abdominal pain, constipation and indigestion (P < 0·05) during the kiwifruit intervention and constipation during the Metamucil® intervention (P < 0·05). This randomised controlled trial demonstrates that daily consumption of three gold-fleshed kiwifruit is associated with a significant increase of two CSBM per week and reduction in gastrointestinal discomfort in mildly constipated adults.

Sex Genotyping of Archival Fixed and Immunolabeled Guinea Pig Cochleas

For decades, outbred guinea pigs (GP) have been used as research models. Various past research studies using guinea pigs used measures that, unknown at the time, may be sex-dependent, but from which today, archival tissues may be all that remain. We aimed to provide a protocol for sex-typing archival guinea pig tissue, whereby past experiments could be re-evaluated for sex effects. No PCR sex-genotyping protocols existed for GP. We found that published sequence of the GP Sry gene differed from that in two separate GP stocks. We used sequences from other species to deduce PCR primers for Sry. After developing a genomic DNA extraction for archival, fixed, decalcified, immunolabeled, guinea pig cochlear half-turns, we used a multiplex assay (Y-specific Sry; X-specific Dystrophin) to assign sex to tissue as old as 3 years. This procedure should allow reevaluation of prior guinea pig studies in various research areas for the effects of sex on experimental outcomes.

Frequency patterns of core constipation symptoms among the Asian adults: a systematic review

BACKGROUND

In clinical practice, assessment of constipation depends on reliability, consistency and frequency of several commonly reported or core symptoms. It is not known if frequency patterns of constipation symptoms in adults are different between the West and the East. This review aimed to describe core constipation symptoms and their frequency patterns among the Asian adults.

METHODS

Articles published in PubMed, MEDLINE, CINAHL and Science Direct from 2005 to 2015 were searched systematically. Studies were included if constipation satisfied the Rome II and or III criteria. Study populations consisted of Asian adults above 18 years old and with sample size above 50.

RESULTS

Of 2812 articles screened, 11 met the eligibility criteria. Constipation among Asian adults was characterized by three core symptoms of 'straining' at 82.8%, 'lumpy and hard stool' at 74.2% and 'sensation of incomplete evacuation' at 68.1% and the least frequent symptom was 'manual maneuver to facilitate defecation' at 23.3%. There was heterogeneity in frequency patterns of core symptoms between different Asian studies but also differences in core symptoms between constipation subtypes of functional constipation and irritable bowel syndrome with constipation.

CONCLUSIONS

In general, Asian adults perceive constipation symptoms in a similar but not equivalent manner to the West. Recognition of core symptoms will increase the diagnostic confidence of constipation and its subtypes but more studies of the various specific Asian populations are needed to address their differences.

Spatial and temporal patterns of diarrhoea in Bhutan 2003-2013

Background

To describe spatiotemporal patterns of diarrhoea in Bhutan, and quantify the association between climatic factors and the distribution and dynamics of the disease.

Methods

Nationwide data on diarrhoea were obtained for 2003 to 2013 from the Health Information and Management System (HIMS), Ministry of Health, Bhutan. Climatic variables were obtained from the Department of Hydro Met Services, Ministry of Economic Affairs, Bhutan. Seasonal trend decomposition was used to examine secular trends and seasonal patterns of diarrhoea. A Bayesian conditional autoregressive (CAR) model was used to quantify the relationship between monthly diarrhoea, maximum temperature, rainfall, age and gender.

Results

The monthly average diarrhoea incidence was highly seasonal. Diarrhoea incidence increased by 0.6% (95% CrI: 0.5–0.6%) for every degree increase in maximum temperature; and 5% (95 Cr I: 4.9–5.1%) for a 1 mm increase in rainfall. Children aged <5 years were found to be 74.2% (95% CrI: 74.1–74.4) more likely to experience diarrhoea than children and adults aged ≥5 years and females were 4.9% (95% CrI: 4.4–5.3%) less likely to suffer from diarrhoea as compared to males. Significant residual spatial clustering was found after accounting for climate and demographic variables.

Conclusions

Diarrhoea incidence was highly seasonal, with positive associations with maximum temperature and rainfall and negative associations with age and being female. This calls for public health actions to reduce future risks of climate change with great consideration of local climatic conditions. In addition, protection of <5 years children should be prioritize through provision of rotavirus vaccination, safe and clean drinking water, and proper latrines.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2611-6) contains supplementary material, which is available to authorized users.

Symptomatology of irritable bowel syndrome and inflammatory bowel disease during the menstrual cycle

Gender-related physiological variations in gastrointestinal (GI) symptomatology have been observed in women of reproductive age. Many women experience cyclical changes in GI symptomatology during their menstrual cycle, particularly alteration in their bowel habits. Physiological studies of healthy women during the menstrual cycle showed a prolonged GI transit time during the luteal phase, either in the oro-cecum route or in the colon. Worsened GI symptoms, such as abdominal pain, bloating or diarrhea are observed in patients with irritable bowel syndrome (IBS) during menses. This may be due to elevated prostaglandin levels during menses, with an enhanced perception of viscera-somatic stimuli resulting in nausea, abdominal distension and pain. Also patients with IBS or IBD demonstrate a cyclical pattern more closely related to their bowel habits than healthy controls. Women with inflammatory bowel disease (IBD) also have exacerbated symptoms during menses; however, it is unclear whether this relates to physiological variation or disease exacerbation in IBS or IBD. Studies examining the association of the menstrual cycle and GI symptomatology in patients with IBS or IBD, have not yet clarified the underlying mechanisms. Moreover medications—such as non-steroidal anti-inflammatory drugs and oral contraceptive pills used for dysmenorrhea and menstrual migraine in those patients have not well been controlled for in the previous studies, which can contribute to further bias. Understanding changes in GI symptomatology during the menstrual cycle may help to determine the true extent of disease exacerbation and proper management strategy.

Distress criterion influences prevalence rates of functional gastrointestinal disorders

Background

Functional gastrointestinal disorders (FGID) are defined by a combination of chronic or recurrent gastrointestinal symptoms. Prevalence rates of FGID are high. Symptoms are associated with distress, and sufferers show high stress levels. However, the current diagnostic criteria do not consider subjective distress elicited by the symptoms, thus potentially leading to overestimated prevalence rates. The aim of this study was to explore the reduction in prevalence rates when distress is considered in the diagnostic criteria.

Methods

In this web-based study, FGID were diagnosed using the Rome II criteria. Prevalence rates with and without subjective distress elicited by the symptoms were computed. Additionally, stress levels and stress reactivity were assessed.

Results

Prevalence rates of FGID in our sample were similar to those in other studies. However, when considering the distress criterion, on average, a decrease of 38.51% was found in the prevalence rates of FGID. Sufferers who were subjectively distressed by their symptoms reported significantly higher stress levels than non-distressed subjects (all p < 0.001).

Conclusions

The consideration of a criterion of subjective distress in the diagnosis of FGID has consequences for actual prevalence rates of FGID. Distressed subjects differ markedly from non-distressed subjects in terms of their stress levels. The inclusion of a distress criterion in the ongoing development of diagnostic criteria for FGID is therefore warranted.

Electronic supplementary material

The online version of this article (doi:10.1186/s12876-014-0215-9) contains supplementary material, which is available to authorized users.

The application of functional magnetic resonance imaging in an infant rat model of irritable bowel syndrome

The aim of this study was to use functional magnetic resonance imaging (BOLD-fMRI) to investigate the activated region associated with visceral pain in the brains of infant rats in a model of IBS. Sixteen newborn rats were randomized into an IBS model group and a control group. Those in the IBS group were separated from their mothers and were mechanically immobilized and had rectal sensitization with mustard essential oil for 1 week. The control group had no treatment. After 2 weeks, balloon catheters were inflated with 5 or 10 mL of air in the rectums of both groups. BOLD-fMRI was performed and the data analyzed by imaging software. In the IBS model group, rectal stimulation with 5 mL air distension activated the anterior cingulate cortex, insula cortex (IC), prefrontal cortex (PFC), and thalamus, while 10 mL air significantly activated the ACC, IC, PFC, and thalamus in the model, but not controls. IBS model group was hypersensitive to visceral stimulation by rectal balloon inflation. The major brain areas participating in visceral sensation included the IC, PFC, and thalamus.

Association between symptoms of irritable bowel syndrome and methane and hydrogen on lactulose breath test

Whether hydrogen and methane gas produced during lactulose breath test (LBT) are associated with symptoms of irritable bowel syndrome (IBS) is not determined. We aimed to investigate whether hydrogen and methane on LBT are associated with IBS symptoms. Sixty-eight IBS patients meeting the Rome III criteria for IBS, and 55 healthy controls, underwent LBT. The IBS subjects recorded their customary gastrointestinal symptoms on a questionnaire using visual analogue scales. LBT positivity was defined to be above 20 ppm rise of hydrogen or 10 ppm rise of methane within 90 min. Gas amounts produced during LBT were determined by calculating area under the curve of hydrogen and methane excretion. Symptom severity scores were not different between the LBT (+) IBS and LBT (-) IBS subjects and also between methane producers and non-methane producers. Gas amounts produced during LBT were not associated with IBS symptoms, except a weak correlation between total gas amounts and a few IBS symptoms such as bloating (r = 0.324, P = 0.039), flatulence (r = 0.314, P = 0.046) and abdominal pain (r = 0.364, P = 0.018) only in LBT (+) IBS. In conclusion, hydrogen and methane gas on LBT are not useful for predicting the customary symptoms and subtypes of IBS.

Brain-Gut Interactions in IBS

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder with an estimated prevalence of 10–20%. Current understanding of the pathophysiology of IBS is incomplete due to the lack of a clearly identified pathological abnormality and due to the lack of reliable biomarkers. Possible mechanisms believed to contribute to IBS development and IBS like symptoms include physical stressors, such as infection or inflammation, psychological, and environmental factors, like anxiety, depression, and significant negative life events. Some of these mechanisms may involve the brain-gut axis (BGA). In this article we review the current knowledge on the possible involvement of the BGA in IBS and discuss new directions for potential future therapies of IBS.

Prevalence and factors associated with irritable bowel syndrome among medical students of Karachi, Pakistan: a cross-sectional study

Background

Irritable bowel syndrome (IBS) and its association with stress, has not been studied among university students in Pakistan. We investigated the prevalence and the pattern of anxiety related IBS symptoms among medical students of Karachi.

Findings

An observational case–control study was carried out at three medical colleges of Karachi, Pakistan. Random sampling was done on 360 medical students. Data was collected using validated tools “Rome III Criteria” and “Generalized Anxiety Disorder Questionnaire”. Participants with IBS were diagnosed on the criteria having experienced abdominal discomfort at least 2–3 days/month associated with high level of anxiety. The apparent prevalence of IBS was found to be 28.3%, with a predominance of 87 (85.29%) females (85.29%) over males (14.71%). The psychological symptoms of anxiety were encountered in 57 (55.8%) participants with IBS, among which males were 15.7% and females 84.2% respectively.

Conclusion

Students who more frequently suffer with mental stress and anxiety are more associated with IBS.

Gut memories: towards a cognitive neurobiology of irritable bowel syndrome

The brain and the gut are engaged in continual crosstalk along a number of pathways collectively termed the 'brain-gut axis'. Over recent years it has become increasingly clear that dysregulation of the axis at a number of levels can result in disorders such as irritable bowel syndrome (IBS). With recent advances in neuroimaging technologies, insights into the neurobiology of IBS are beginning to emerge. However the cognitive neurobiology of IBS has remained relatively unexplored to date. In this review we summarise the available data on cognitive function in IBS. Moreover, we specifically address three key pathophysiological factors, namely; stress, immune activation and chronic pain, together with other factors involved in the manifestation of IBS, and explore how each of these components may impact centrally, what neurobiological mechanisms might be involved, and consider the implications for cognitive functioning in IBS. We conclude that each factor addressed could significantly impinge on central nervous system function, supporting the view that future research efforts must be directed towards a detailed assessment of cognitive function in IBS.

Proteomic analysis of colonic mucosa in a rat model of irritable bowel syndrome

Irritable bowel syndrome (IBS) is one of the most common functional disorders of the gastrointestinal tract. It is characterized by abdominal pain and changes in bowel habits. Various studies have investigated the pathophysiologic processes underlying IBS, but the mechanism remains poorly understood. In the present study, we established an IBS model and identified differentially expressed proteins in colon tissue of IBS rats compared with healthy controls by 2-D gel electrophoresis, MALDI-TOF-MS, and Western blot analysis. Our results showed that 13 of the 1396 protein spots on 2-D gel were differently expressed between the IBS and control groups. Ontological analysis of these proteins revealed primary roles in catalytic activity (protein disulfide-isomerase A3, glyoxalase I, cathepsin S, alpha-enolase), structural support (cytokeratin 8), antioxidant activity (peroxiredoxin-6), protein binding (transgelin, serpin peptidase inhibitor B5), and signal transduction (40S ribosomal protein SA). Protein disulfide-isomerase A3 and cytokeratin 8 overexpression in IBS were confirmed by Western blot. The findings indicate that multiple proteins are involved in IBS processes that influence intestinal tract immunity, inflammation, and nerve regulation. Our study provides useful candidate genes and proteins for further investigation.

Do fluctuations in ovarian hormones affect gastrointestinal symptoms in women with irritable bowel syndrome?

BACKGROUND

An increase in gastrointestinal (GI) symptoms, including bowel discomfort, abdominal pain/discomfort, bloating, and alterations in bowel patterns, has been reported during premenses and menses menstrual cycle phases and the perimenopause period in women with and without irritable bowel syndrome (IBS).

OBJECTIVE

This article reviews the literature related to one possible physiological mechanism-declining or low ovarian hormone levels--that may underlie the occurrence or exacerbations of abdominal pain/discomfort at times of low ovarian hormones (menses, menopause) in women with or without IBS.

METHODS

To identify English-only review and data-based articles, PubMed was searched between January 1980 and September 2008 using the following terms: irritable bowel syndrome, functional gastrointestinal disorders, gastrointestinal motility, immune, pain, hyperalgesia, menstrual cycle, menopause, pregnancy, estrogen, estradiol (E(2)), and progesterone. Studies in animals and in humans were included; drug trials were excluded.

RESULTS

From our review of the literature, 18 papers were identified that were related either to the mechanisms accounting for menstrual cycle fluctuations (n = 12) or to the impact of menopausal status on symptoms of IBS (n = 6). One study reported that visceral pain sensitivity was significantly higher during menses than at other menstrual cycle phases in women with IBS (P < 0.05). Other menstrual cycle phase-linked symptoms, dysmenorrheal symptoms (cramping pain) in particular, were more intense in women with IBS. Animal studies have shed some light on the relationship of ovarian hormones to GI sensorimotor function.

CONCLUSION

The increase in GI symptoms around the time of menses and early menopause occurs at times of declining or low ovarian hormones, suggesting that estrogen and progesterone withdrawal may contribute either directly or indirectly. This review highlights the need for confirmatory preclinical and clinical studies to unravel the role of ovarian hormones in women with IBS.

Meta-analysis: do irritable bowel syndrome symptoms vary between men and women?

BACKGROUND

Studies suggest that sex and gender-related differences exist in irritable bowel syndrome (IBS), but data is often conflicting.

AIM

To evaluate gender differences and the effect of menstrual cycle and menopausal status on IBS symptoms.

METHODS

We performed a systematic review of MEDLINE to search for studies comparing IBS symptoms between gender, menstrual cycle phases and menopausal states in IBS and/or healthy individuals. We performed meta-analyses to compare the relative risk (RR) of individual IBS symptoms between men and women.

RESULTS

Twenty-two studies measured gender differences in IBS symptoms. Women were more likely to report abdominal pain (RR = 1.12, 95% CI: 1.02, 1.22) and constipation-related symptoms (RR = 1.12, 95% CI: 1.02, 1.23) than men (all P < 0.05). However, men with IBS were more likely to report diarrhoea-related symptoms than women with IBS (RR = 0.84, 95% CI: 0.75, 0.94, P < 0.05). A systematic review of 13 studies demonstrated that both IBS and healthy women reported increased IBS symptoms during menses vs. other phases. There were insufficient data to determine the effect of menopause and hormone supplementation on IBS symptoms.

CONCLUSIONS

In the general and IBS populations, gender differences in IBS symptoms exist, although these differences are modest. Studies suggest that female sex hormones influence the severity of IBS symptoms, but more studies are needed.

Sex, gender, and pain: a review of recent clinical and experimental findings

Sex-related influences on pain and analgesia have become a topic of tremendous scientific and clinical interest, especially in the last 10 to 15 years. Members of our research group published reviews of this literature more than a decade ago, and the intervening time period has witnessed robust growth in research regarding sex, gender, and pain. Therefore, it seems timely to revisit this literature. Abundant evidence from recent epidemiologic studies clearly demonstrates that women are at substantially greater risk for many clinical pain conditions, and there is some suggestion that postoperative and procedural pain may be more severe among women than men. Consistent with our previous reviews, current human findings regarding sex differences in experimental pain indicate greater pain sensitivity among females compared with males for most pain modalities, including more recently implemented clinically relevant pain models such as temporal summation of pain and intramuscular injection of algesic substances. The evidence regarding sex differences in laboratory measures of endogenous pain modulation is mixed, as are findings from studies using functional brain imaging to ascertain sex differences in pain-related cerebral activation. Also inconsistent are findings regarding sex differences in responses to pharmacologic and non-pharmacologic pain treatments. The article concludes with a discussion of potential biopsychosocial mechanisms that may underlie sex differences in pain, and considerations for future research are discussed.

PERSPECTIVE

This article reviews the recent literature regarding sex, gender, and pain. The growing body of evidence that has accumulated in the past 10 to 15 years continues to indicate substantial sex differences in clinical and experimental pain responses, and some evidence suggests that pain treatment responses may differ for women versus men.

Irritable bowel syndrome: does gender matter?

In industrialized parts of the world, women seek health care services for irritable bowel syndrome (IBS) more frequently than men. The role of gender in IBS is likely multifactorial involving inherent physiological differences in gonadal hormones, stress reactivity, and inflammatory responses, as well as sociocultural differences in response to pain and/or bowel pattern changes. This mini-review in particular addresses gender differences in visceral sensitivity, motility, and autonomic nervous system balance as potential factors contributing to gender differences in IBS presentation.

State-of-the-art of irritable bowel syndrome and inflammatory bowel disease research in 2008

Irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) are two of the leading causes of chronic intestinal conditions in the world. This issue of World Journal of Gastroenterology (WJG) presents a series of papers from world experts who discuss the current knowledge and opinions on these important conditions. Although great strides have been made in the diagnosis, treatment and pathology of IBS and IBD; much has yet to be explained. The etiologies and risk factors of these multifactorial conditions remain elusive. Specific diagnostic biomarkers need to be developed and safer treatments developed. The burden of IBS and IBD on the healthcare system is felt with repeated medical care visits and high costs. IBS and IBD patients can account for 30%-50% of office visits at gastroenterology services/clinics. Over one million people have IBD in the United States, with 30 000 new cases being diagnosed every year. One-quarter million people in the UK are afflicted with IBD. The cost of medical care in the United States for IBD is estimated to be $1.8 billion/year.