An Asia-Pacific, double blind, placebo controlled, randomised study to evaluate the efficacy, safety, and tolerability of tegaserod in patients with irritable bowel syndrome

The effect of tegaserod on symptoms and quality of life in korean women with irritable bowel syndrome with constipation

INTRODUCTION

Tegaserod has been used for treatment of irritable bowel syndrome (IBS) but there is no data regarding its effect on Korean patients. The aim of this study was to evaluate the effect of tegaserod on symptoms and quality of life (QOL) in Korean female IBS patients with constipation and to evaluate the usefulness of the IBS-QOL in clinical study.

METHODS

A prospective, open labeled, multicenter study was performed. Female patients fulfilling Rome II criteria for IBS received 6 mg of tegaserod twice a day for 4 weeks. The efficacy on IBS symptoms and QOL was assessed using 7-point scaled symptom questionnaire and IBS-QOL questionnaire, respectively.

RESULTS

A total of 81 female patients (range 18-73 years of age) were enrolled in this study. Tegaserod therapy significantly reduced the overall symptom scores after 4 weeks (p <0.01). The improved symptoms included abdominal discomfort or pain, hard or lumpy stool, straining during a bowel movement, feeling of incomplete bowel movement, and abdominal fullness or bloating. The IBS-QOL of responders to tegaserod treatment was also significantly improved after 4 weeks (p <0.01). Furthermore, improvement of symptom scores significantly correlated with improvement of the IBS-QOL scores (r = -0.60, p <0.001).

CONCLUSIONS

Tegaserod 6 mg given twice daily improved the QOL as well as the bowel symptoms in Korean female IBS patients with constipation. The IBS-QOL can be used as a reliable end-point in clinical study.

The effect of tegaserod on symptoms and quality of life in korean women with irritable bowel syndrome with constipation

INTRODUCTION

Tegaserod has been used for treatment of irritable bowel syndrome (IBS) but there is no data regarding its effect on Korean patients. The aim of this study was to evaluate the effect of tegaserod on symptoms and quality of life (QOL) in Korean female IBS patients with constipation and to evaluate the usefulness of the IBS-QOL in clinical study.

METHODS

A prospective, open labeled, multicenter study was performed. Female patients fulfilling Rome II criteria for IBS received 6 mg of tegaserod twice a day for 4 weeks. The efficacy on IBS symptoms and QOL was assessed using 7-point scaled symptom questionnaire and IBS-QOL questionnaire, respectively.

RESULTS

A total of 81 female patients (range 18-73 years of age) were enrolled in this study. Tegaserod therapy significantly reduced the overall symptom scores after 4 weeks (p <0.01). The improved symptoms included abdominal discomfort or pain, hard or lumpy stool, straining during a bowel movement, feeling of incomplete bowel movement, and abdominal fullness or bloating. The IBS-QOL of responders to tegaserod treatment was also significantly improved after 4 weeks (p <0.01). Furthermore, improvement of symptom scores significantly correlated with improvement of the IBS-QOL scores (r = -0.60, p <0.001).

CONCLUSIONS

Tegaserod 6 mg given twice daily improved the QOL as well as the bowel symptoms in Korean female IBS patients with constipation. The IBS-QOL can be used as a reliable end-point in clinical study.

Pharmacological management of constipation

The approach of this review is to give a pragmatic approach to using laxatives, based on a combination of what is known about mechanism of action and the available literature on evidence.

Post-infectious irritable bowel syndrome

Post-infectious irritable bowel syndrome (PI-IBS) is a common disorder wherein symptoms of IBS begin after an episode of acute gastroenteritis. Published studies have reported incidence of PI-IBS to range between 5% and 32%. The mechanisms underlying the development of PI-IBS are not fully understood, but are believed to include persistent sub-clinical inflammation, changes in intestinal permeability and alteration of gut flora. Individual studies have suggested that risk factors for PI-IBS include patients’ demographics, psychological disorders and the severity of enteric illness. However, PI-IBS remains a diagnosis of exclusion with no specific disease markers and, to date, no definitive therapy exists. The prognosis of PI-IBS appears favorable with spontaneous and gradual resolution of symptoms in most patients.

Efficacy of 5-HT3 antagonists and 5-HT4 agonists in irritable bowel syndrome: systematic review and meta-analysis

OBJECTIVES

Irritable bowel syndrome (IBS) is a chronic functional disorder. 5-Hydroxytryptamine (5-HT) is a key modulator of gastrointestinal sensorimotor function. Many patients have IBS that can be difficult to treat, which has led to the development of newer agents, such as 5-HT(3) antagonists and 5-HT(4) agonists. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to estimate the efficacy of all available 5-HT agents in IBS.

METHODS

MEDLINE, EMBASE, and the Cochrane Controlled Trials Register were searched (up to June 2008). Trials recruiting adults with IBS in primary, secondary, or tertiary care comparing 5-HT(3) antagonists or 5-HT(4) agonists with placebo were eligible. Dichotomous symptom data were pooled to obtain a relative risk (RR) of remaining symptomatic after therapy, with a 95% confidence interval (CI). The number needed to treat (NNT) was calculated from the reciprocal of the risk difference.

RESULTS

The strategic search identified 1,593 citations. A total of 29 RCTs were eligible for inclusion; placebo was compared with 5-HT(3) antagonists in 11 RCTs, with tegaserod in 11, and with mixed 5-HT(3) antagonists/5-HT(4) agonists in 7. The study quality was generally high. The RR of IBS symptoms persisting with 5-HT(3) antagonists vs. placebo was 0.78 (95% CI: 0.71-0.86), with a similar benefit for both alosetron and cilansetron. Tegaserod was also superior to placebo (RR=0.85; 95% CI: 0.80-0.90). Renzapride and cisapride had no benefit in IBS.

CONCLUSIONS

Alosetron, cilansetron, and tegaserod are all effective in the treatment of IBS. Serious adverse events were rare in the eligible RCTs included in this systematic review.

The treatment of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a highly prevalent functional bowel disorder routinely encountered by healthcare providers. Although not life-threatening, this chronic disorder reduces patients' quality of life and imposes a significant economic burden to the healthcare system. IBS is no longer considered a diagnosis of exclusion that can only be made after performing a battery of expensive diagnostic tests. Rather, IBS should be confidently diagnosed in the clinic at the time of the first visit using the Rome III criteria and a careful history and physical examination. Treatment options for IBS have increased in number in the past decade and clinicians should not be limited to using only fiber supplements and smooth muscle relaxants. Although all patients with IBS have symptoms of abdominal pain and disordered defecation, treatment needs to be individualized and should focus on the predominant symptom. This paper will review therapeutic options for the treatment of IBS using a tailored approach based on the predominant symptom. Abdominal pain, bloating, constipation and diarrhea are the four main symptoms that can be addressed using a combination of dietary interventions and medications. Treatment options include probiotics, antibiotics, tricyclic antidepressants, selective serotonin reuptake inhibitors and agents that modulate chloride channels and serotonin. Each class of agent will be reviewed using the latest data from the literature.

Editorial: is adequate relief fatally flawed or adequate as an end point in irritable bowel syndrome?

There is controversy on the validity of binary end points used in irritable bowel syndrome (IBS) clinical trials. In a usual-care observational study, baseline severity influenced the response measured as satisfactory relief. This editorial reviews the observations from a non-pharmacological study to assess the effect of baseline severity on the performance of binary end points in large drug trials. The pivotal finding is that once the patients who reported adequate relief at baseline were excluded from the analysis, baseline severity no longer affected the proportion of patients reporting adequate relief of IBS with treatment. As large drug trials enriched the study cohorts for at least moderate severity after a no-treatment, run-in period, it seems likely that the precaution of excluding mild disease de facto resolved the hypothetical weakness of the adequate relief end point. Given the high responsiveness and longitudinal construct validity demonstrated with adequate relief end point, it should be accepted as a trial end point.

Adequate relief in a treatment trial with IBS patients: a prospective assessment

OBJECTIVES

Adequate relief (AR) of irritable bowel syndrome (IBS) symptoms (IBS-AR) has been used as a primary end point in many randomized controlled trials of IBS and is considered by the Rome III committee to be an acceptable primary end point. However, controversy exists on whether baseline severity confounds the effect of the treatment outcome. The aim (1) is to compare a subjective report of IBS-AR with global assessment of improvement (IBS-GAI), change in IBS symptom severity scale (IBS-SSS), and IBS quality of life (IBS-QOL); (2) to explore whether initial IBS symptom severity influences the ability of these outcome measures to detect differences post treatment; and (3) to determine whether psychological symptoms influence the sensitivity of these measures, in a randomized controlled treatment trial.

METHODS

A total of 289 adult IBS patients were recruited to a treatment trial. Baseline IBS-SSS scores were used to classify IBS severity as mild (<175), moderate (175-300), or severe (>300). Questionnaires were completed at baseline and after 3 weeks of treatment with sham acupuncture or wait-list control.

RESULTS

IBS baseline severity (IBS-SSS) significantly affected the proportion of patients who reported IBS-AR at 3 weeks (mild, 70%; moderate, 49.7%; severe, 38.8%) (P<0.05). However, once the patients who reported IBS-AR at baseline (28.0%) were excluded from the analysis, baseline severity no longer affected the proportion of patients reporting IBS-AR. Baseline severity did not have a significant effect on patients reporting moderate or significant improvement on the IBS-GAI (mild, 30%; moderate, 25.3%; severe, 18.8%) (P=NS). Psychological symptoms had no significant correlations with responders after adjusting for baseline severity.

CONCLUSIONS

These data suggest that IBS-AR as an end point is inversely related to baseline symptom severity. However, if patients who report AR at screening were excluded from study participation, baseline symptom severity was no longer confounded with a report of AR at the study end point.

New treatments for irritable bowel syndrome in women

The estimated prevalence of irritable bowel syndrome (IBS) in Western countries is 7-15%, with a female:male ratio of 2-2.5:1 in IBS patients who seek healthcare services; however, the female predominance is lower in the general population. IBS has a significant impact on health-related quality of life and is associated with a significant healthcare and economic burden. Management of IBS is comprised of general measures and pharmacologic and nonpharmacologic treatment. However, there are ongoing efforts to find more effective therapeutic approaches. As advancements in the understanding of the pathophysiology of IBS continue to grow, new and effective treatments with novel mechanisms of action that have the potential to improve relief of IBS symptoms over current treatments are likely to be developed. This article provides an overview of current and emerging therapies for IBS and also highlights sex and gender differences in clinical trials and treatment response.

Management of chronic constipation in the elderly

Constipation is a significant healthcare problem in the elderly. However, while undoubtedly common in the elderly, data on the prevalence of constipation in general and of its subtypes vary considerably, depending on the nature of the study population and their location. Furthermore, the complexity of the pathophysiology of constipation in this age group is little appreciated. Assumptions regarding 'age-related changes in colorectal physiology' are, for the most part, not supported by scientific evidence and may serve to distract the clinician from uncovering the contributions of co-morbid diseases and the impact of iatrogenic factors. The evidence base from which one can develop recommendations on the management of constipation in the elderly is, for the most part, slim. This becomes most starkly apparent when one attempts to critically assess specific approaches to management. There is insufficient evidence to support the use of many commonly used laxatives both in the general population and in the elderly. Lifestyle interventions have value for some patients but data are lacking on the benefits of these interventions for patients with chronic constipation. Data in the elderly do not exist for most new pharmacological approaches to constipation. Pending the availability of good data, management of constipation in the elderly should be tailored to each individual's needs and expectations, regardless of age or place of residence. In certain situations, constipation may be complicated by the development of impaction; preventive strategies are important in this context. We urge enrolment of many more elderly individuals with chronic constipation in clinical trials designed to address their particular needs.

Challenges to the therapeutic pipeline for irritable bowel syndrome: end points and regulatory hurdles

Recent advances in our understanding of basic neuroenteric mechanisms and the role of effectors and transmitters in the brain-gut axis have provided opportunities to develop new therapeutic agents for irritable bowel syndrome (IBS). Furthermore, human pharmacodynamic studies utilizing transit, colonic, or rectal sensitivity and brain imaging have been useful in determining therapeutic efficacy (particularly for drugs that act on motor function). This review provides an overview of medications that have not yet been approved for treatment of patients with IBS yet have shown promise in phase IIB trials. These include drugs that act on the serotonin receptor and transporter system: antidepressants, norepinephrine reuptake inhibitors, opioids, cholecystokinin antagonists, neurokinin-antagonists, chloride channel activators, guanylate cyclase C agonists, atypical benzodiazepines, probiotics, and antibiotics. The changing landscape in the regulatory approval process has impacted the development of IBS drugs. Guidance documents from regulatory agencies in Europe and the United States have focused on patients' reported outcomes and associated quality of life. After a decade of experience with different end points that have generated some data on psychometric validation and unprecedented information about responsiveness of the binary or global end points to drug therapy, it is necessary to pursue further validation studies before or during pivotal phase IIB or III trials. The hope of providing relief to patients should galvanize all parties to achieve these goals.

Updates on treatment of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a highly prevalent gastrointestinal disorder characterized by abdominal pain and discomfort in association with altered bowel habits. It is estimated to affect 10%-15% of the Western population, and has a large impact on quality of life and (in)direct healthcare costs. IBS is a multifactorial disorder involving dysregulation within the brain-gut axis, and it is frequently associated with gastrointestinal motor and sensory dysfunction, enteric and central nervous system irregularities, neuroimmune dysregulation, and post-infectious inflammation. As with other functional medical disorders, the treatment for IBS can be challenging. Conventional therapy for those with moderate to severe symptoms is largely unsatisfactory, and the development of new and effective drugs is made difficult by the complex pathogenesis, variety of symptoms, and lack of objective clinical findings that are the hallmark of this disorder. Fortunately, research advances over the past several decades have provided insight into potential mechanisms responsible for the pathogenesis of IBS, and have led to the development of several promising pharmaceutical agents. In recent years there has been much publicity over several of these new IBS medications (alosetron and tegaserod) because of their reported association with ischemic colitis and cardiovascular disease. While these agents remain available for use under restricted prescribing programs, this highlights the need for continued development of safe and effective medication for IBS. This article provides a physiologically-based overview of recently developed and frequently employed pharmaceutical agents used to treat IBS, and discusses some non-pharmaceutical options that may be beneficial in this disorder.

The trials and tribulations of drug development for functional gastrointestinal disorders

Functional gastrointestinal disorders (FGID) are common conditions seen in primary care and specialty practices but many affected individuals report a lack of satisfaction with available treatments. Despite the unmet need for more effective pharmacotherapy, drug development for these conditions can be challenging on many levels. This review will discuss the rationale and challenges of drug development for FGID. The reasons for engaging in drug development include that these conditions are highly prevalent, associated with a significant economic and healthcare burden, and associated with a lack of satisfaction with current therapies. The challenges include the lack of perception that FGID are legitimate disorders, the multidimensional and complex pathophysiology of FGID, the lack of a biological marker for diagnosis and treatment response, the heterogeneity of the patient population, the lack of consensus regarding the best outcome measures for clinical trials and the perceived increased risk-benefit ratio associated with drugs for FGID. Ongoing efforts are being taken to work towards a better understanding of pathophysiology, illness severity, patient-reported outcome measures, and benefit : risk assessment, and towards increasing education and communication amongst patients, clinicians, investigators, industry and regulatory agencies which will hopefully help optimize drug development strategies for FGID.

Tegaserod for female patients suffering from IBS with mixed bowel habits or constipation: a randomized controlled trial

OBJECTIVES

Though the greatest proportion of irritable bowel syndrome (IBS) patients report a mixed bowel pattern (IBS-Mixed), no available therapies have been rigorously evaluated in this subgroup. This study aimed to evaluate the efficacy and safety of the 5-HT(4) agonist tegaserod in women with IBS-Mixed and IBS with constipation (IBS-C).

METHODS

This prospective, double-blind, randomized, placebo-controlled, multicenter study was conducted in 100 centers in North America, South America, and Europe. Women with IBS-Mixed or IBS-C received tegaserod 6 mg or placebo twice daily. The primary efficacy variable was the patient's assessment of satisfactory relief over the 4-wk treatment period. The proportion of patients reporting satisfactory relief for >/=3 of 4 treatment weeks (75% rule) and individual IBS symptoms were assessed.

RESULTS

In total, 661 women were randomized (IBS-Mixed 324, IBS-C 337). Baseline symptom assessments identified clear differences between the two cohorts. Tegaserod provided significant improvement in satisfactory relief of IBS symptoms over 4 wk (OR 1.75, 95% CI 1.35-2.25, P < 0.001) in both IBS-Mixed and IBS-C patients. Using the 75% rule, 52.3% of tegaserod-receiving IBS-M patients and 43.3% of IBS-C patients were responders (vs 36.3, OR 1.88, 95% CI 1.16-3.04, P < 0.010; and 28.9, OR 1.90, 95% CI 1.19-3.05, P < 0.008 for placebo, respectively). The most frequent adverse events leading to study discontinuation in tegaserod-treated patients were diarrhea (1.5%) and abdominal pain (0.9%). Overall 7% of IBS-C patients reported diarrhea compared to 12% of IBS-Mixed (placebo 2.4%, 1.8%, respectively).

CONCLUSIONS

Tegaserod is effective in treating overall IBS symptoms in patients with IBS-Mixed and IBS-C.

A double blind randomized controlled trial of a probiotic combination in 100 patients with irritable bowel syndrome

OBJECTIVES

The purpose of this study was to evaluate the effects of a probiotic combination on symptoms in patients with irritable bowel syndrome (IBS).

METHODS

We investigated the efficiency of a probiotic dietary supplement, containing four strains of lactic acid bacteria, on symptoms of IBS. One hundred and sixteen patients with IBS fulfilling the Rome II criteria were randomized in a parallel group, double-blind study to receive a placebo or a probiotic combination (1 x 10(10) cfu once daily) for four weeks. The symptoms that were monitored weekly included discomfort, abdominal pain, and stool frequency and quality. Quality of life was assessed before and at the end of the treatment using the SF36 and FDD-quality-of-life questionnaires.

RESULTS

One hundred subjects completed the study (48 probiotic combination, 52 placebo). The probiotic combination was not superior to the placebo in relieving symptoms of IBS (42.6 versus 42.3% improvement). However, the decrease of abdominal pain between the first and the fourth week of treatment was significantly higher in probiotic treated patients (-41.9 versus -24.2%, P=0.048). Interesting findings from the IBS sub-groups were also observed such as a lower pain score at end point in patients with alternating bowel habits (P=0.023) and an increase of stool frequency in the constipated sub-group from the first week of probiotic treatment (P=0.043).

CONCLUSIONS

The probiotic combination was not significantly superior to the placebo in relieving symptoms of IBS. Despite the apparent high placebo response, interesting findings from IBS sub-groups were observed in the field of abdominal pain and stool frequency.

Sensory signalling effects of tegaserod in patients with irritable bowel syndrome with constipation

Tegaserod relieves overall and multiple individual constipation-predominant irritable bowel syndrome (IBS-C) symptoms. However, mechanisms for the relief of abdominal pain/discomfort are not well understood. The effects of tegaserod on rectal sensitivity to distension were measured by the nociceptive flexion RIII reflex, as evidenced by spinal hyperexcitability (i.e. increase or facilitation of the RIII reflex), in IBS-C patients. A randomized, double-blind, placebo-controlled, parallel study was performed in 30 women with IBS-C. The effects of slow ramp rectal distension on the RIII reflex, recorded from the lower limb, were measured before [first experimental day (D1)] and after 7 days [day 8 (D8)] of placebo (n=15) or 6 mg tegaserod bid (n=15). Pressure-volume and sensation-volume relationships were measured during distension, and patients reported their IBS symptoms daily. On D1, rectal distension facilitated the RIII reflex in both treatment groups. On D8 vs D1 these facilitatory effects were significantly lower (P<0.001, analysis of variance) after tegaserod (mean reduction: -30.3+/-11.9%) than placebo (mean reduction: -10.1+/-12.9%). No significant changes in the volume-sensation relationship or differences in compliance were observed with tegaserod or placebo. In conclusion, tegaserod reduces the facilitatory effects of rectal distension on the RIII reflex in women with IBS-C.

Neurogastroenterology of tegaserod (HTF 919) in the submucosal division of the guinea-pig and human enteric nervous system

Actions of the 5-HT(4) serotonergic receptor partial agonist, tegaserod, were investigated on mucosal secretion in the guinea-pig and human small intestine and on electrophysiological behaviour of secretomotor neurons in the guinea-pig small intestinal submucosal plexus. Expression of 5-HT(4) receptor protein and immunohistochemical localization of the 5-HT(4) receptor in the submucosal plexus in relation to expression and localization of choline acetyltransferase and the vesicular acetylcholine (ACh) transporter were determined for the enteric nervous system of human and guinea-pig small intestine. Immunoreactivity for the 5-HT(4) receptor was expressed as ring-like fluorescence surrounding the perimeter of the neuronal cell bodies and co-localized with the vesicular ACh transporter. Exposure of mucosal/submucosal preparations to tegaserod in Ussing chambers evoked increases in mucosal secretion reflected by stimulation of short-circuit current. Stimulation of secretion had a relative high EC(50) of 28.1 +/- 1.3 mumol L(-1), was resistant to neural blockade and appeared to be a direct action on the secretory epithelium. Tegaserod acted at presynaptic 5-HT(4) receptors to facilitate the release of ACh at nicotinic synapses on secretomotor neurons in the submucosal plexus. The 5-HT(2B) receptor subtype was not involved in actions at nicotinic synapses or stimulation of secretion.

Tegaserod use in children: a single-center experience

BACKGROUND

Tegaserod is increasingly prescribed by pediatric gastroenterologists even though there are few published data concerning its use in children. The aim of this study was to describe the authors' experience with tegaserod in children.

PATIENTS AND METHODS

Patients treated with tegaserod from 2004 through 2006 were included in this study. Defecation and fecal incontinence frequency and global assessment of relief of symptoms were assessed.

RESULTS

Seventy-two patients (44 girls) ranging in age from 1.1 to 18.3 years constitute the patient sample of this report. The median age was 10 years and the median follow-up after initiation of tegaserod treatment was 11.3 months (range 2.3-45.2 months). Indications to prescribe tegaserod were constipation (58%) and a variety of other conditions including functional dyspepsia or inflammatory bowel disease (42%). Defecation frequency increased after tegaserod use (1 vs 7/week, P < 0.001) and presence of fecal incontinence decreased (47% vs 23%, P < 0.001) in the constipation group. Parents rated relief of constipation as moderate or significant in 71% of cases in the constipation group. In the group with other indications to start tegaserod therapy, moderate or significant relief of abdominal pain and bloating was noted in 64% and 68% of patients, respectively. The median dose of tegaserod prescribed was 0.22 mg x kg x day (range 0.05-0.87 mg x kg(-1) x day(-1)). Adverse events were observed in 32% of the patients. The most common side effects were self-limiting diarrhea (20%) and abdominal pain (8%). Only one patient discontinued tegaserod because of side effects; this patient experienced pain at his cecostomy site.

CONCLUSIONS

Tegaserod seems to relieve a variety of functional gastrointestinal symptoms in children. Further randomized controlled studies are needed to support the specific pediatric target of prescribing tegaserod.

Review article: abdominal bloating and distension in functional gastrointestinal disorders--epidemiology and exploration of possible mechanisms

BACKGROUND

A sensation of abdominal bloating, sometimes accompanied by an increase in girth (distension), is one of the most common and most intrusive features of functional bowel disorders.

AIM

To conduct a systematic, evidence-based review of the epidemiology and pathophysiology of abdominal bloating and its relationship to distension.

METHODS

The terms bloating, distension, functional bowel, irritable bowel syndrome, constipation and diarrhoea were searched on MEDLINE up to 2006. References from selected articles and relevant abstracts were also included.

RESULTS

Approximately 50% of irritable bowel syndrome patients with bloating also experience an increase in abdominal girth and this is more pronounced with constipation than diarrhoea. Bloating appears to be more frequently associated with visceral hypersensitivity, whereas distension is more often related to hyposensitivity and delayed transit. Although there is little evidence for excessive gas as a cause of bloating, gas infusion studies suggest that handling of gas may be impaired in irritable bowel syndrome and there may also be abnormal relaxation of the anterior abdominal musculature in these patients.

CONCLUSIONS

There is unlikely to be a single cause for bloating and distension, which probably have different, but overlapping, pathophysiological mechanisms. Relieving constipation might help distension, but the treatment of bloating may need more complex approaches involving sensory modulation.

Syndrome de l'intestin irritable: options thérapeutiques actuelles

Relieving abdominal pain is the principal treatment objective for patients with irritable bowel syndrome. No single drug stands out in the treatment strategy for this illness. Antispasmodics, magnesium aluminum silicates, and alverine citrate drugs all remain initial options for treatment, although their prescription is impeded by the fact that an increasing number are no longer approved for reimbursement. Increased dietary fibers often have a harmful effect on symptoms. Some patients are probably intolerant to some foods but there is no satisfactory proof on which to base a restrictive diet. Improved knowledge of the pathophysiology of irritable bowel syndrome has made it possible to diversify treatments that act first on one of the key pathophysiologic elements, visceral hypersensitivity. Antidepressants (especially tricyclics) can be used at low doses. Among the serotonergic drugs, serotonin 5-HT4 receptors agonists (tegaserod) may be available soon, but the development of 5-HT3 antagonists (alosetron, cilansetron) has been stopped for safety reasons (ischemic colitis and severe constipation). Non-drug options such as hypnosis, psychotherapy, relaxation, or yoga, may also be proposed to some patients. Probiotics are a possible treatment in the future.

Further validation of the IBS-QOL: female Mexican IBS patients have poorer quality of life than females from North Carolina

The Irritable Bowel Syndrome (IBS)-Quality of Life (QOL) is the most extensively validated health-related quality of life (HRQOL)-specific instrument for IBS with appropriate evidence for psychometric validity. Our aim was to linguistically validate the IBS-QOL for Mexico according to standard guidelines, to conduct further psychometric validation, and to compare the HRQOL between IBS patients from Mexico and North Carolina (University of North Carolina). Construct validity was tested by correlating scores from the Mexican Spanish IBS-QOL with those for anxiety and depression obtained by the Hospital Anxiety and Depression scale. Also, HRQOL from Rome I female IBS patients who consulted a tertiary referral center in Mexico was compared with that of female patients from UNC matched by age and bowel habit. A general univariate linear model was done to determine the most important variable over HRQOL, place of origin, or bowel habit. The majority of the IBS-QOL items had a negative correlation with depression as well as with anxiety. Compared to patients from UNC, the Mexican ones reported significant lower scores on Body Image and Health Worry and a trend in Interference with activities and in the Overall score. There were some differences in Dysphoria and Interference that were related to bowel habit, independently of the place of origin. In conclusion, the IBS-QOL validated in Mexican Spanish has shown construct validity. Using this instrument we found that female IBS patients who consulted a tertiary referral center in Mexico have lower HRQOL than those in North Carolina at least in factors such as Body Image and Health Worry.

The association of serotonin transporter genetic polymorphisms and irritable bowel syndrome and its influence on tegaserod treatment in Chinese patients

The aims of this study were to investigate the relationship of genetic polymorphisms of the serotonin reuptake transporter and the clinical subtypes of irritable bowel syndrome and its influence on the efficacy of tegaserod in Chinese irritable bowel syndrome patients with constipation. Genetic polymorphisms were analyzed in 87 patients and 96 controls, then 41 irritable bowel syndrome patients with constipation received tegaserod for 4 weeks. The primary efficacy variable was the responder rate measured by Subject's Global Assessment of Relief. Secondary efficacy assessed the changes of individual symptoms weekly. There was no significant difference in genotype frequencies between the patients as a whole and the control group. The frequency of the L/L genotype in the serotonin transporter gene-linked polymorphic region was significantly higher in patients with constipation than in controls (25.0% vs. 7.3%). Responder rates to tegaserod were significantly higher in the S/S (85.0%) and L/S (70.0%) than in the L/L genotype (36.4%). All secondary variables also significantly improved in the S/S and L/S groups compared to the L/L group. This study suggests the hypothesis that individuals with the L/L genotype are vulnerable to development of irritable bowel syndrome with constipation, and patients with the L/L genotype respond poorly to treatment with a routine dose of tegaserod.

Studying sex and gender differences in pain and analgesia: a consensus report

In September 2006, members of the Sex, Gender and Pain Special Interest Group of the International Association for the Study of Pain met to discuss the following: (1) what is known about sex and gender differences in pain and analgesia; (2) what are the "best practice" guidelines for pain research with respect to sex and gender; and (3) what are the crucial questions to address in the near future? The resulting consensus presented herein includes input from basic science, clinical and psychosocial pain researchers, as well as from recognized experts in sexual differentiation and reproductive endocrinology. We intend this document to serve as a utilitarian and thought-provoking guide for future research on sex and gender differences in pain and analgesia, both for those currently working in this field as well as those still wondering, "Do I really need to study females?"

Tegaserod for the treatment of irritable bowel syndrome and chronic constipation

BACKGROUND

IBS is a complex disorder that encompasses a wide profile of symptoms. The symptoms of chronic constipation frequently resemble those of constipation-predominant IBS. Current drug treatments for irritable bowel syndrome (IBS) are of limited value. Many target specific symptoms only. Tegaserod, a 5HT(4) partial agonist, represents a novel mechanism of action in the treatment of IBS and chronic constipation.

OBJECTIVES

The objective of this review was to evaluate the efficacy and tolerability of tegaserod for the treatment of IBS and chronic constipation in adults and adolescents aged 12 years and above.

SEARCH STRATEGY

MEDLINE 1966-December 2006 and EMBASE 1980 to December 2006 were searched. The text and key words used included "tegaserod", "HTF 919", "irritable bowel", "constipation" and "colonic diseases, functional". The Cochrane Central Register of Controlled Trials, and the Inflammatory Bowel Disease Review Group Specialized Trials Register were also searched. Searches stopped on 15th December 2006. Relevant articles were retrieved, and their reference lists were also reviewed.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials comparing tegaserod with placebo, no treatment or any other intervention (pharmacological or non-pharmacological) in subjects aged 12 years and above with a diagnosis of IBS or chronic constipation, focusing on clinical endpoints were considered for review.

DATA COLLECTION AND ANALYSIS

Study inclusion and exclusion, data extraction and quality assessment was undertaken by two authors independently. Meta-analysis was performed where study populations, designs, outcomes, and statistical reporting allowed combination of data in a valid way, using the summary statistics relative risk for dichotomous data and weighted mean difference for continuous data, both with 95% CI. Thirteen short-term placebo-controlled studies fulfilled the inclusion criteria. These were predominantly conducted in women. Ten studies evaluated the efficacy of tegaserod on global gastrointestinal (GI) symptoms in patients with constipation-predominant IBS (C-IBS). One small study evaluated safety in patients with diarrhoea-predominant IBS. Two studies evaluated the effectiveness of tegaserod for the treatment of chronic constipation.

MAIN RESULTS

In patients with C-IBS, the relative risk (RR) of being a responder in terms of global relief of GI symptoms during the last 4 weeks of treatment was significantly higher with both tegaserod 12 mg and 4 mg doses compared with placebo. Although the pooled results indicate statistically significant benefit with tegaserod, the a priori minimal clinically important differences set in two of three studies were not reached. The responder rate for this endpoint was also higher when considered for the first 4 weeks of treatment (tegaserod 12 mg only). Tegaserod did not significantly improve the patients' individual symptoms of abdominal pain and discomfort although bowel habit showed a statistically significant improvement with tegaserod 4 mg and there was a non-significant trend in this outcome in favour of tegaserod 12 mg. In patients with chronic constipation, the RR of being a responder in terms of complete spontaneous bowel movements per week with tegaserod 12 mg was 1.54 (95% CI 1.35 to 1.75), WMD for this endpoint compared with placebo 0.6 (95% CI 0.42 to 0.78). Differences between tegaserod and placebo in increases in frequency of bowel movements were small (less than one per week). The proportion of patients with either diagnosis who experienced diarrhea was significantly higher in the tegaserod 12 mg group compared with placebo (RR 2.80, 95% CI 2.13 to 3.68), with a number needed to harm (NNH) of 20. Effects of tegaserod on GI symptoms such as bloating, stool consistency, and straining were not consistent across the studies.

AUTHORS' CONCLUSIONS

Tegaserod appears to improve the overall symptomatology of IBS, and the frequency of bowel movements in those with chronic constipation. The clinical importance of these modest improvements is not clear. There are currently few data on its effect on quality of life. In addition, more information is needed about its efficacy in men. It would also be of interest to know whether treatment with tegaserod leads either directly, or indirectly, to changes in visceral sensitivity or psychopathology, which are also considered important in the pathophysiology of these conditions.

Does co-administration of a non-selective opiate antagonist enhance acceleration of transit by a 5-HT4 agonist in constipation-predominant irritable bowel syndrome? A randomized controlled trial

Opioid neurons exhibit tonic restraint on intestinal motility; opioid antagonists stimulate peristalsis and increase transit. In vitro, 5-hydroxytryptamine (5-HT4) agonists combined with selective opioid antagonists significantly increased colonic propulsion relative to a 5-HT4 agonist alone. We hypothesized that the combination of 5-HT4 agonist and non-selective opioid antagonist enhances intestinal transit more than either treatment alone in female constipation-predominant irritable bowel syndrome (C-IBS) patients. Our aim was to examine the effect of tegaserod 6 mg b.i.d. alone and combined with naltrexone 50 mg on intestinal transit and stool characteristics in females with C-IBS. Forty-eight patients were randomized to tegaserod alone, naltrexone alone or in combination with tegaserod or placebo for 6 days. Small bowel, ascending colon half-life (in pharmacokinetics) (t1/2), and colonic geometric centre (8, 24, 48 h) were assessed by scintigraphy. Tegaserod increased small bowel (P < 0.01) and colon transit (P < 0.01). Naltrexone did not accelerate colonic transit relative to placebo. Combination treatment did not significantly accelerate transit relative to tegaserod alone. Tegaserod and tegaserod with naltrexone resulted in looser stool form (P < 0.01). In female C-IBS patients, tegaserod accelerates small bowel and colon transit and contributed to looser stool consistency. Use of naltrexone, 50 mg, does not support the hypothesis that combination of 5-HT4 agonist and non-selective opioid antagonist enhances intestinal transit.

Irritable bowel syndrome: current approach to symptoms, evaluation, and treatment

There are frequent advances in knowledge about the clinical presentation, pathophysiology, and treatment of irritable bowel syndrome. It is important for clinicians to be aware of available therapies and the supporting evidence for those therapies to increase patient satisfaction. This is best achieved with a collaborative and long-term clinician-patient relationship and mutual commitment to modify therapy and try new modalities until the greatest relief of symptoms and improvement in health-related quality of life is achieved. This article reviews symptoms, comorbidities, gender differences, and measure of severity in irritable bowel syndrome and current and evidence-based approaches to evaluation and treatment, and the new symptom-based Rome III diagnostic criteria are reviewed and explained.

Mechanisms of serotonergic agents for treatment of gastrointestinal motility and functional bowel disorders

Most of the body's serotonin is released in the gut where it plays an important role in the control of gastrointestinal (GI) motility, sensitivity and muscle tone by activating different receptor subtypes. This review focuses on the known effects of selective serotonin reuptake inhibitor and serotonin receptor agonists and antagonists on the sensorimotor function of the GI tract and describes the therapeutic potential of these actions for GI motility and functional bowel disorders.

Effect of tegaserod on colonic transit time in male patients with constipation-predominant irritable bowel syndrome

BACKGROUND AND AIMS

Tegaserod is approved for the treatment of constipation-predominant irritable bowel syndrome (C-IBS) in females. The aim of this study was to evaluate the effect of tegaserod on colonic transit time (CTT) and symptoms in male patients with C-IBS.

METHODS

Forty-four males with C-IBS (Rome II) were enrolled. After a baseline washout period of 2 weeks, 40 patients were randomized to 6 mg twice daily of tegaserod or placebo for 12 weeks. Daily bowel habits and weekly satisfactory relief of symptoms were recorded. Total and segmental CTT were measured using radiopaque markers at baseline and after treatment.

RESULTS

The mean +/- SD for the total colonic, right colonic, left colonic and rectosigmoid transit time (in hours) were 18.96 +/- 3.92, 7.74 +/- 1.55, 5.64 +/- 1.51 and 5.58 +/- 2.2 in the tegaserod group compared to 22.47 +/- 3.73, 9.69 +/- 2.33, 6.6 +/- 1.32 and 6.18 +/- 2.22 in the placebo group at the end of 12 weeks. There was a statistically significant difference in the total, right and left CTT in the tegaserod group (P < 0.05) at the end of treatment. Global satisfactory relief at the end of 12 weeks was 75% in the tegaserod group and 50% in the placebo group (P > 0.05). Greater stool frequency occurred in the tegaserod group (P > 0.05). There was a significant decrease in the stool consistency at the end of 12 weeks in patients treated with tegaserod (P < 0.05).

CONCLUSIONS

Tegaserod causes significant acceleration of CTT in male patients with C-IBS. Although there was a trend towards improvement in bowel symptoms in the treated group, this effect was not statistically significant.

Safety, tolerability and satisfaction with tegaserod therapy in Asia-Pacific patients with irritable bowel syndrome with constipation

BACKGROUND AND AIM

The 5-HT(4) receptor agonist tegaserod (6 mg b.i.d.) provides significantly better overall multiple symptom relief compared with placebo in patients with irritable bowel syndrome with constipation (IBS-C). The clinical benefit and safety of tegaserod in IBS-C patients has been demonstrated worldwide in several studies. The aim of this study was to obtain further safety and tolerability data in patients with IBS in the Asia-Pacific region, and to assess patients' satisfaction and compliance with treatment and willingness to re-use tegaserod in a post-marketing setting.

METHODS

A multicenter, single-arm, open-label trial was conducted at 869 outpatient centers in 10 countries. Men and women with IBS, whose predominant bowel symptom was not diarrhea (non-D-IBS), received tegaserod for 4-12 weeks. Safety and tolerability were assessed by recording adverse events (AE). Patients were questioned about compliance, satisfaction with treatment and willingness to use tegaserod in future.

RESULTS

Data were available from 14 537 patients (18% men, 82% women). Four percent of patients reported at least one AE. The most common AE were diarrhea (2%) and abdominal pain (1%), and most treatment-related AE occurred in the first week of treatment. Serious AE (SAE) were observed in eight patients, and no deaths were reported. Most patients (79%) reported to be satisfied or very satisfied with treatment, and 76% stated they would use tegaserod in the future. Compliance was 97%.

CONCLUSIONS

Tegaserod has a favorable safety and tolerability profile for treating non-D-IBS and IBS-C in men and women in the Asia-Pacific region. Satisfaction with tegaserod treatment can be expected in the majority of patients.

Cancer-related constipation

Cancer-related constipation is common and a significant detractor from patient quality of life. It has many possible causes and is still not well understood. Information is lacking on therapies for cancer-related constipation among current medications approved by the US Food and Drug Administration (FDA). Most agents have only been formally tested in comparison with placebo in chronic idiopathic constipation if at all. Few comparative studies of laxatives have been performed to establish superiority or synergy. As we understand more about the physiology of the gastrointestinal tract, new targeted therapies have become available. These include a selective chloride channel activator, lubiprostone, and a selective 5HT4 serotonin receptor agonist, tegaserod, both of which have been FDA approved for chronic idiopathic constipation. The role of these agents in cancer-related constipation remains to be seen. On the horizon are two investigational peripherally acting opioid receptor antagonists, alvimopan and methylnaltrexone. Preliminary results in cancer-related constipation suggest that these agents may be important additions to our treatment repertoire.

Economic evaluation of tegaserod vs. placebo in the treatment of patients with irritable bowel syndrome: an analysis of the TENOR study

OBJECTIVES

Tegaserod is effective, safe, and well-tolerated in the treatment of patients with irritable bowel syndrome (IBS) with constipation. The aim of this study was to assess, from a payer perspective, the cost-effectiveness of tegaserod in the treatment of IBS patients, based on the TEgaserod in NORdic region (TENOR) trial data.

METHODS

Female and male patients (Rome II criteria) were randomized to receive tegaserod 6 mg b.i.d. or placebo for 12 weeks. Patients (247 tegaserod; 238 placebo) completed the EuroQol EQ-5D questionnaire at baseline, Week 4, and Week 12. A 12-week economic study was undertaken to assess the incremental cost-effectiveness ratio (ICER) of tegaserod in terms of cost per quality-adjusted life-year (QALY) gained. Cost-effectiveness acceptability curves were calculated to estimate the probability of tegaserod being cost-effective at different benchmark values of cost per QALY gained.

RESULTS

By assuming a daily drug cost to payers of Euro 2, Euro 3, and Euro 4, the ICER of tegaserod ranges between Euro 19,000 and Euro 38,000 per QALY gained, with the percentage of the bootstrap estimates below the willingness to pay level of Euro 50,000 per QALY gained ranging between 90% and 69%.

CONCLUSIONS

This study established directly from a randomized controlled clinical trial that tegaserod is cost-effective in the treatment of non-D-IBS patients.

Novel and alternative therapies for childhood constipation

Constipation is a worldwide problem that affects many children. Treatment of constipation is largely based on clinical experience rather than on evidence-based controlled clinical trials. Stool softeners and cathartic agents in combination with behavioral interventions constitute the programs most commonly used to facilitate painless and frequent defecation. Long-term treatment is needed for most patients, and approximately 30% of children beyond puberty continue to struggle with symptoms of constipation, such as infrequent, painful evacuation of stools and fecal incontinence. Not surprisingly, chronicity of these bowel complaints may cause significant interference with the child's emotional growth and development. Development of new therapeutic strategies is necessary in order to treat these challenging patients more effectively. This review provides an overview of novel and alternative therapies, such as new drugs, surgery, and probiotics, that are being proposed for the treatment of childhood chronic constipation.

Review article: the role of antibiotics vs. conventional pharmacotherapy in treating symptoms of irritable bowel syndrome

BACKGROUND

The concept of augmenting the management of irritable bowel syndrome with antibiotics is evolving, and many questions remain regarding this therapy relative to known and hypothesized irritable bowel syndrome pathophysiology. The clinical evidence of small intestinal bacterial overgrowth as an important aetiology of irritable bowel syndrome continues to accumulate. Clinical symptoms of bacterial overgrowth and irritable bowel syndrome are similar; however, a definitive cause-and-effect relationship remains unproven. It is unclear whether motility dysfunction causes bacterial overgrowth or gas products of enteric bacteria affect intestinal motility in irritable bowel syndrome.

AIM

To discusses the efficacy and tolerability of current symptom-directed pharmacotherapies and of antibiotics in the treatment of irritable bowel syndrome.

METHODS

A computerized search of PubMed was performed with search terms "IBS", "pharmacotherapy" and "antibiotics". Relevant articles were selected, and the reference list of selected articles was reviewed to identify additional references.

RESULTS

Antibiotic treatment benefits a subset of irritable bowel syndrome patients. The non-absorbed antibiotic rifaximin has a favourable safety and tolerability profile compared with systemic antibiotics and demonstrates a therapeutic efficacy comparable with symptom-based irritable bowel syndrome pharmacotherapies.

CONCLUSION

Rifaximin is the only antibiotic with demonstrated sustained benefit beyond therapy cessation in irritable bowel syndrome patients in a placebo-controlled trial. Whether antibiotics can improve quality of life in patients with irritable bowel syndrome warrants further research.

Primary endpoints for irritable bowel syndrome trials: a review of performance of endpoints

The choice of primary endpoint for a clinical trial is one of the most important determinants of the ability of a clinical trial to demonstrate efficacy of therapeutic agents. Although there are still no clear, universally accepted guidelines on the definition of clinical benefit for irritable bowel syndrome (IBS), consensus guidelines stress the importance of using validated endpoints. This article reviews the evidence available in the literature on the psychometric validation and performance of the 3 endpoints recommended by the Rome III Committee for use as primary endpoints in treatment trials of IBS. The Rome III Committee recommends 2 types of measures: binary endpoints addressing the construct of relief (that is, adequate relief and satisfactory relief) and an integrative symptom questionnaire that addresses the change in severity of a representative group of symptoms of IBS (that is, the IBS Severity Scale). The current evidence suggests that at present, adequate relief should be recognized by regulatory authorities as an acceptable primary endpoint in clinical trials. This analysis also suggests that data from individual clinical trials should be pooled and undergo meta-analysis, and that prospective studies should be considered to further characterize the performance of available endpoints as outcome measures in pharmacotherapeutic trials in IBS.

Trigemino-cardiac reflex during transsphenoidal surgery for pituitary adenomas: Methodological description of a prospective skull base study protocol

A systematic clinical neuroscience protocol is described for the use to examine the trigemino-cardiac reflex (TCR) response in humans. Target neurosurgical conditions are operations that require manipulations around the peripheral and central part of the trigeminal nerve and its branches, e.g. the cerebellopontine angle or the sellar region. To assess the hemodynamic and cardiac responses of patients after TCR initiation, anesthetic monitoring has been applied. The TCR is defined as a drop of more than 20% of the heart rate and the mean arterial blood pressure compared with the baseline values before the stimulus and coinciding with the surgical manipulation at or around any branches of the trigeminal nerve. By help of illustrative cases, we present for the first time preliminary results regarding the differentiation of the TCR in a central and a peripheral induction during transsphenoidal surgery of pituitary adenomas. Based on these results, we can conclude that we have developed a battery of preoperative examination procedures based on event-related diagnostics that was useful to differentiate different subgroups of TCR during transsphenoidal surgery. The presented protocol can be performed directly pre-, intra- and postoperatively and applied for assessment of TCR even in patients with known risk factors.

Tegaserod for constipation-predominant irritable bowel syndrome

Tegaserod, a selective and partial agonist at the 5-hydroxytryptamine (5-HT [serotonin]) receptor subtype 4 (5-HT4), is the only United States Food and Drug Administration-approved drug for the treatment of constipation-predominant irritable bowel syndrome (IBS) in women. The drug's stimulation of 5-HT4 receptors on intestinal enterocytes increases peristaltic activity and fluid secretion into the gut lumen, facilitating stool passage. In addition, affinity of tegaserod for 5-HT4 receptors modulates visceral sensitivity, which helps alleviate abdominal pain associated with constipation-predominant IBS. The drug's pharmacokinetic and pharmacodynamic parameters do not differ significantly with age or sex. Tegaserod safely and effectively relieves overall gastrointestinal symptoms and abdominal discomfort and normalizes bowel habits in patients with constipation-predominant IBS. It is associated with few drug interactions. In clinical studies, tegaserod was well tolerated, and its adverse-effect profile was similar to that of placebo. Severe diarrhea, as well as abdominal pain, flatulence, headache, and nausea, were the most commonly reported events. Patients who experience severe diarrhea should discontinue the drug. With the data available, tegaserod remains an option for patients with constipation-predominant IBS.

Tegaserod in the treatment of irritable bowel syndrome (IBS) with constipation as the prime symptom

Irritable bowel syndrome with constipation (IBS-C) as the predominant bowel symptom is a prevalent disorder, characterized by recurring abdominal pain/discomfort, bloating, and constipation, and imposes a significant socio-economic burden. Traditional treatments generally address just one of the multiple IBS symptoms. The efficacy and safety profile of tegaserod, a serotonin 5-HT(4) receptor agonist, has been demonstrated in several randomized, placebo-controlled, and open-label trials. This review discusses the major clinical trials of tegaserod, which have involved 8948 IBS patients. Overall, data reveal that tegaserod is an effective treatment for IBS-C, providing statistically significant relief of overall and multiple individual IBS-C symptoms (abdominal pain/discomfort, bloating, and constipation) in both placebo-controlled and "real-life" open-label settings. Repeat treatments with tegaserod were also shown to be effective, which is noteworthy given the chronic and episodic nature of IBS. Moreover, tegaserod was associated with improvements in patients' quality of life and work productivity. Data also indicate that tegaserod is well tolerated over the short-term (4 weeks), long-term (12 months), and repeated treatments. Diarrhea is the only adverse event consistently associated with tegaserod and was generally mild and transient. Overall, tegaserod has been demonstrated to offer effective and well-tolerated treatment of IBS-C, providing patients with meaningful symptom relief.

Efficacy of tegaserod for functional constipation in Chinese subjects: a randomized double-blind controlled trial in a single centre

BACKGROUND

Tegaserod has been shown to be effective in chronic constipation in Western population. Aim We investigated if tegaserod is equally effective in Chinese population.

MATERIALS AND METHODS

Two hundred and fifty patients were randomized to a double-blinded 8-week treatment of tegaserod 6 mg b.d. or placebo. Response during weeks 1-4 was defined as an increase in complete spontaneous bowel motion >/=1/week. Secondary efficacy included response during weeks 1-8, individual symptoms and scores, quality of life and global assessment of bowel habits and constipation.

RESULTS

One hundred and nine patients from the treatment group and 107 from the placebo group completed the 8-week treatment. Responder rates was 47.7% vs. 29% for the treatment and placebo groups (P = 0.005). The sustained complete spontaneous bowel motion rate was 29.4% vs. 15.7% in the two groups (P = 0.016). The response rates were higher than that reported previously in the Caucasian studies. There was improvement in the scores for stool form scale, bothersomeness of constipation, abdominal distension/bloating and satisfaction of bowel habit (P < 0.05). The mental score was higher in the treatment group (46.8 +/- 9 vs. 43.6 +/- 10, P = 0.01).

CONCLUSIONS

Tegaserod is effective in relieving chronic constipation in Chinese population. The efficacy observed may be higher than that in Western population.

Mechanisms of hypersensitivity in IBS and functional disorders

General introduction The concept of visceral hypersensitivity is accepted as being germane to several functional gastrointestinal disorders (FGIDs). The causes or risk factors associated with this hypersensitivity are unclear. This article addresses the proposed mechanisms leading to hypersensitivity: from genetic to inflammatory disorders, from central to peripheral alterations of function. However, in order to place visceral hypersensitivity in a more global perspective as an aetiological factor for FGIDs, it also provides a review of recent evidence regarding the role of other peripheral mechanisms (the intraluminal milieu), as also genetic factors in the pathophysiology of these disorders. The article has been divided into five independent sections. The first three sections summarize the evidence of visceral hypersensitivity as a biological marker of functional gut disorders, the peripheral and central mechanisms involved, and the role of inflammation on hypersensitivity. In opposition to visceral hypersensitivity as an isolated phenomenon in functional gut disorders, the last two sections focus on the importance of peripheral mechanisms, like motor disturbances, specifically those resulting on altered transport of intestinal gas, and alterations of the intraluminal milieu and genetics.

The serotonin signaling system: from basic understanding to drug development for functional GI disorders

Serotonin is an important gastrointestinal signaling molecule. It is a paracrine messenger utilized by enterochromaffin (EC) cells, which function as sensory transducers. Serotonin activates intrinsic and extrinsic primary afferent neurons to, respectively, initiate peristaltic and secretory reflexes and to transmit information to the central nervous system. Serotonin is also a neurotransmitter utilized by a system of long descending myenteric interneurons. Serotonin is synthesized through the actions of 2 different tryptophan hydroxylases, TpH1 and TpH2, which are found, respectively, in EC cells and neurons. Serotonin is inactivated by the serotonin reuptake transporter (SERT)-mediated uptake into enterocytes or neurons. The presence of many serotonin receptor subtypes enables selective drugs to be designed to therapeutically modulate gastrointestinal motility, secretion, and sensation. Current examples include tegaserod, a 5-HT(4) partial agonist, which has been approved for treatment of irritable bowel syndrome (IBS) with constipation in women and for chronic constipation in men and women. The 5-HT(3) antagonists, granisetron and ondansetron, are useful in combating the nausea associated with cancer chemotherapy, and alosetron is employed in the treatment of IBS with diarrhea. Serotonergic signaling abnormalities have also been putatively implicated in the pathogenesis of functional bowel diseases. Other compounds, for which efficacy has not been rigorously established, but which may have value, include tricyclic antidepressants and serotonin selective reuptake inhibitors to combat IBS, and 5-HT(1) agonists, which enhance gastric accommodation, to treat functional dyspepsia. The initial success encountered with serotonergic agents holds promise for newer and more potent insights and therapies of brain-gut disorders.

Irritable bowel syndrome in the 21st century: perspectives from Asia or South-east Asia

Asian irritable bowel syndrome (IBS) studies not only confirm the truth of this functional disorder but also describe the current disease situation of this continent, with its variable socioeconomic backgrounds. Most Asian community IBS prevalence is within 5-10%, regardless of gender or ethnic character. As well as meeting the main Rome II criteria, Asian IBS subjects also have many minor symptoms. Thus this recommendation remains useful to diagnose Asian IBS. Also, female patients commonly express constipation-predominant (C-) symptoms. Extra-colonic symptoms are common in Asia, for example dyspepsia, insomnia and irritable urinary bladder. Asian IBS subjects do experience psychological disturbances including anxiety, depression, agoraphobia and neuroticism. Accordingly, their quality of life is poor and there is absenteeism leading to excessive physician visits. Abnormal gut motor and sensory functions have been indicated among the Asian IBS subjects. Now, there is evidence of altered colonic neuroimmune function leading to gut hypersensitivity and dysmotility. An Asia-Pacific trial also confirmed tegaserod efficacy on female C-IBS subjects. More than 90% of nurses have very limited IBS knowledge, and are unable even to explain it clearly. In conclusion, Western recommended criteria clearly diagnose Asian IBS and many factors are mutual leading to IBS. Current IBS treatments remain useful but additional reeducation for medical professionals appears to be needed.

Prevalence, impact and attitudes toward lower gastrointestinal dysmotility and sensory symptoms, and their treatment in Canada: A descriptive study

OBJECTIVES

To investigate the impact of lower gastrointestinal (GI) symptoms in the general Canadian population, and to explore patient satisfaction with traditional therapies and the level of patient interest in new treatments. patients and

METHODS

Stage 1: A telephone survey of a weighted sample of 1000 adults (18 years of age or older) was conducted to determine the prevalence of five GI symptoms--abdominal pain, abdominal discomfort, bloating, constipation or constipation with occasional diarrhea- that were present for 12 weeks or more (not necessarily consecutive) over the past year. Respondents with only abdominal pain were excluded. Stage 2: A telephone survey of 689 women (18 to 64 years of age), experiencing the GI symptoms described in stage 1, was conducted to assess symptom impact and treatment satisfaction.

RESULTS

Overall, 5.2% of the Canadian population (2.3% men and 7.9% women) experienced one or more lower GI symptoms (excluding those reporting abdominal pain alone). In stage 2, 26.2% of respondents had previously been diagnosed with irritable bowel syndrome. Overall, 78.1% of participants experienced two or more symptoms. Bloating was the most common symptom (75.3%) and abdominal pain the most bothersome and most severe. Over the previous three months, 13.2% of respondents missed work or school and 28.8% were less productive. At least one physician (average of 2.2 physicians) was consulted for symptoms in 80.9% of respondents. Of the 63.8% women receiving treatment, most used nonprescription products. Patients receiving prescription treatments for constipation were most often dissatisfied (75%).

CONCLUSIONS

Abdominal pain and discomfort, bloating and constipation are common, frequently occurring symptoms in the Canadian population and have a high burden on work performance and health care seeking. Most patients were dissatisfied with traditional therapies.

Irritable Bowel Syndrome: A Practical Review

The epidemiology and current understanding of the pathophysiology of irritable bowel syndrome is reviewed, beginning with a historical perspective. The roles of genetics, environment, allergy, infection and inflammation, bacterial overgrowth, hormones and motility abnormalities are discussed. Using the current evidence-based literature, the practical approach of diagnosis and treatment is outlined, including traditional modalities and newer therapeutic agents such as serotonin modulators.

Health-related quality of life, work productivity, and health care resource utilization of subjects with irritable bowel syndrome: Baseline results from logic (longitudinal outcomes study of gastrointestinal symptoms in Canada), a naturalistic study

BACKGROUND

Abdominal pain/discomfort, bloating, and constipation are gastrointestinal dysmotility and sensory symptoms associated with irritable bowel syndrome (IBS). No studies have followed patients with IBS symptoms for 1 year under conditions of routine clinical practice to assess prospectively the impact of treatments on health outcomes.

OBJECTIVE

The objective of this ongoing, naturalistic study is to assess the long-term impact of IBS treatments on quality of life (QOL), work productivity, and resource utilization. This report describes the baseline characteristics and patterns of care of the patients enrolled in this study.

METHODS

Patients with physician-diagnosed IBS symptoms were enrolled from 147 physician sites across Canada between May 4, 2004, and March 31, 2005. Clinical data were collected at baseline and at the end of the 12-month follow-up (patients were followed for 1 year between May 4, 2005, and March 31, 2006). Patient-reported outcomes were collected at baseline and at months 1, 2, 6, 9, and 12. Health-related QOL, health status, and work productivity were assessed with the IBS-QOL, a 5-item EuroQol descriptive system, and Work Productivity and Activity Impairment questionnaires, respectively. A resource utilization questionnaire elicited information on physician; visits, treatments, and procedures. Baseline data are reported here.

RESULTS

Data were obtained from 1555 patients; 85.1% (1320/1552) were women. Patients had a mean (SD) age of 45.8 (15.0) years and mean (SD) duration of IBS symptoms of 11.4 (11.5) years. Self-reported bowel patterns were predominantly constipation (41.0%, 587/1433) and constipation alternating with diarrhea (39.4%, 564/1433); 60.3% (938/1555) of subjects used > or =3 IBS treatments in the previous 4 weeks. Approximately 50% of all patients reported distress "quite a bit or "extremely" for abdominal pain, gas, bloating, and constipation. The mean overall IBS-QOL score (0-100 scale, with 0 indicating poor QOL) was 66.3; food avoidance (51.8) and health worry (59.3) were the most serious concerns. Patients reported 5.6% work absenteeism, 31.4% presenteeism, and 34.6% overall work productivity loss, equivalent to 13.8 hours lost productivity per 40-hour workweek.

CONCLUSIONS

The baseline data from this ongoing, prospective, naturalistic study are consistent with previous findings that suggested significant use of health care resources with concomitant low QOL and decreased work productivity in patients with IBS symptoms.