New concepts on intestinal microbiota and the role of the non-absorbable antibiotics with special reference to rifaximin in digestive diseases.

Digestive diseases are a broad range of chronic disorders that substantially and negatively impact the patients' quality of life. Here, we review our current understanding on the pathophysiology of hepatic encephalopathy, irritable bowel syndrome, and diverticular disease, with a special focus on the gut microbiota composition associated with these disorders. Furthermore, we review the current clinical practice for their therapeutic treatments, including probiotics, diet change, non-adsorbable disaccharides, and antibiotics. We highlight that broad-spectrum non-adsorbable antibiotics, such as rifaximin, are quite effective and safe for the treatment of all essayed digestive diseases.

[Irritable bowel syndrome with constipation and functional constipation in adults: Treatment (Part 2 of 2)]. / Guía de práctica clínica del síndrome del intestino irritable con estreñimiento y estreñimiento funcional en adultos: tratamiento. (Parte 2 de 2).

In this Clinical practice guide we examine the diagnostic and therapeutic management of adult patients with constipation and abdominal discomfort, at the confluence of the spectrum of irritable bowel syndrome and functional constipation. Both fall within the framework of functional intestinal disorders and have major personal, health and social impact, altering the quality of life of the patients affected. The former is a subtype of irritable bowel syndrome in which constipation and altered bowel habit predominate, often along with recurring abdominal pain, bloating and abdominal distension. Constipation is characterised by infrequent or hard-to-pass bowel movements, often accompanied by straining during defecation or the sensation of incomplete evacuation. There is no underlying organic cause in the majority of cases; it being considered a functional bowel disorder. There are many clinical and pathophysiological similarities between the two conditions, the constipation responds in a similar way to commonly used drugs, the fundamental difference being the presence or absence of pain, but not in an "all or nothing" way. The severity of these disorders depends not only on the intensity of the intestinal symptoms but also on other biopsychosocial factors: association of gastrointestinal and extraintestinal symptoms, degree of involvement, forms of perception and behaviour. Functional bowel disorders are diagnosed using the Rome criteria. This Clinical practice guide adapts to the Rome IV criteria published at the end of May 2016. The first part (96, 97, 98) examined the conceptual and pathophysiological aspects, alarm criteria, diagnostic test and referral criteria between Primary Care and Gastroenterology. This second part reviews all the available treatment alternatives (exercise, fluid ingestion, diet with soluble fibre-rich foods, fibre supplements, other dietary components, osmotic or stimulating laxatives, probiotics, antibiotics, spasmolytics, peppermint essence, prucalopride, linaclotide, lubiprostone, biofeedback, antdepressants, psychological treatment, acupuncture, enemas, sacral root neurostimulation and surgery), and practical recommendations are made for each.

[Irritable bowel syndrome with constipation and functional constipation in adults: Treatment (Part 2 of 2)]. / Guía de práctica clínica del síndrome del intestino irritable con estreñimiento y estreñimiento funcional en adultos: tratamiento. (Parte 2 de 2).

In this Clinical practice guide we examine the diagnostic and therapeutic management of adult patients with constipation and abdominal discomfort, at the confluence of the spectrum of irritable bowel syndrome and functional constipation. Both fall within the framework of functional intestinal disorders and have major personal, health and social impact, altering the quality of life of the patients affected. The former is a subtype of irritable bowel syndrome in which constipation and altered bowel habit predominate, often along with recurring abdominal pain, bloating and abdominal distension. Constipation is characterised by infrequent or hard-to-pass bowel movements, often accompanied by straining during defecation or the sensation of incomplete evacuation. There is no underlying organic cause in the majority of cases; it being considered a functional bowel disorder. There are many clinical and pathophysiological similarities between the two conditions, the constipation responds in a similar way to commonly used drugs, the fundamental difference being the presence or absence of pain, but not in an "all or nothing" way. The severity of these disorders depends not only on the intensity of the intestinal symptoms but also on other biopsychosocial factors: association of gastrointestinal and extraintestinal symptoms, degree of involvement, forms of perception and behaviour. Functional bowel disorders are diagnosed using the Rome criteria. This Clinical practice guide adapts to the Rome IV criteria published at the end of May 2016. The first part (96, 97, 98) examined the conceptual and pathophysiological aspects, alarm criteria, diagnostic test and referral criteria between Primary Care and Gastroenterology. This second part reviews all the available treatment alternatives (exercise, fluid ingestion, diet with soluble fibre-rich foods, fibre supplements, other dietary components, osmotic or stimulating laxatives, probiotics, antibiotics, spasmolytics, peppermint essence, prucalopride, linaclotide, lubiprostone, biofeedback, antdepressants, psychological treatment, acupuncture, enemas, sacral root neurostimulation and surgery), and practical recommendations are made for each.

[Clinical practice guidelines: Irritable bowel syndrome with constipation and functional constipation in adults: Concept, diagnosis, and healthcare continuity. (Part 1 of 2)]. / Guía de práctica clínica: síndrome del intestino irritable con estreñimiento y estreñimiento funcional en adultos: concepto, diagnóstico y continuidad asistencial. (Parte 1 de 2).

In this Clinical practice guide, an analysis is made of the diagnosis and treatment of adult patients with constipation and abdominal discomfort, under the spectrum of irritable bowel syndrome and functional constipation. These have an important personal, health and social impact, affecting the quality of life of these patients. In irritable bowel syndrome with a predominance of constipation, this is the predominant change in bowel movements, with recurrent abdominal pain, bloating and frequent abdominal distension. Constipation is characterised by infrequent or difficulty in bowel movements, associated with excessive straining during bowel movement or sensation of incomplete evacuation. There is often no underling cause, with an intestinal functional disorder being considered. They have many clinical and pathophysiological similarities, with a similar response of the constipation to common drugs. The fundamental difference is the presence or absence of pain, but not in a way evaluable way; "all or nothing". The severity depends on the intensity of bowel symptoms and other factors, a combination of gastrointestinal and extra-intestinal symptoms, level of involvement, forms of perception, and behaviour. The Rome criteria diagnose functional bowel disorders. This guide is adapted to the Rome criteria IV (May 2016) and in this first part an analysis is made of the alarm criteria, diagnostic tests, and the criteria for referral between Primary Care and Digestive Disease specialists. In the second part, a review will be made of the therapeutic alternatives available (exercise, diet, drug therapies, neurostimulation of sacral roots, or surgery), making practical recommendations for each one of them.

[Clinical practice guidelines: Irritable bowel syndrome with constipation and functional constipation in adults: Concept, diagnosis, and healthcare continuity. (Part 1 of 2)]. / Guía de práctica clínica: síndrome del intestino irritable con estreñimiento y estreñimiento funcional en adultos: concepto, diagnóstico y continuidad asistencial. (Parte 1 de 2).

In this Clinical practice guide, an analysis is made of the diagnosis and treatment of adult patients with constipation and abdominal discomfort, under the spectrum of irritable bowel syndrome and functional constipation. These have an important personal, health and social impact, affecting the quality of life of these patients. In irritable bowel syndrome with a predominance of constipation, this is the predominant change in bowel movements, with recurrent abdominal pain, bloating and frequent abdominal distension. Constipation is characterised by infrequent or difficulty in bowel movements, associated with excessive straining during bowel movement or sensation of incomplete evacuation. There is often no underling cause, with an intestinal functional disorder being considered. They have many clinical and pathophysiological similarities, with a similar response of the constipation to common drugs. The fundamental difference is the presence or absence of pain, but not in a way evaluable way; "all or nothing". The severity depends on the intensity of bowel symptoms and other factors, a combination of gastrointestinal and extra-intestinal symptoms, level of involvement, forms of perception, and behaviour. The Rome criteria diagnose functional bowel disorders. This guide is adapted to the Rome criteria IV (May 2016) and in this first part an analysis is made of the alarm criteria, diagnostic tests, and the criteria for referral between Primary Care and Digestive Disease specialists. In the second part, a review will be made of the therapeutic alternatives available (exercise, diet, drug therapies, neurostimulation of sacral roots, or surgery), making practical recommendations for each one of them.

Gastrointestinal Physiological Changes and Their Relationship to Weight Loss Following the POSE Procedure.

BACKGROUND: Primary Obesity Surgery Endolumenal (POSE) is a novel bariatric endoscopic procedure that has been shown to reduce weight safely through 12 months. The study investigated potential mechanisms of weight loss following POSE. METHODS: Patients with class I-II obesity received transmural plications in the gastric fundus and distal gastric body. Patients were evaluated at baseline and at 2- and 6-month follow-up with gastric-emptying (GE) scintigraphy, a validated test of intake capacity (kcal) and plasma glucose homeostasis hormones/gastrointestinal peptides. Weight was recorded through 15 months. Mean data and 95% CIs are reported. Regression modeling assessed variables that influenced total weight loss (%TWL) and excess weight loss (%EWL). RESULTS: POSE was performed on 18 patients (14 F/4 M); mean age 39 years (34-44), body mass index (BMI, kg/m(2)) 36 (95% CI, 35; 37). At 15 months (n = 15), mean TWL was 19.1 ± 6.6% (15.5; 22.8) and EWL was 63.7 ± 25.1% (49.8; 77.6). At 2 and 6 months (n = 18), intake capacity decreased significantly from 901 (685; 1117) to 473 (345; 600) and 574 kcal (418; 730), respectively (p < 0.001). At 2 months, GE was delayed but returned to baseline levels at 6 months (n = 18). Glucose/insulin ratio improved (p < 0.05). Postprandial decrease in ghrelin was enhanced (p = 0.03) as well as postprandial increase in PYY (p = 0.001). The best model for EWL prediction 15 months after POSE (R (2): 66%, p = 0.006) included pre-POSE BMI, post-POSE GE, and postprandial PYY increase. CONCLUSIONS: The POSE procedure was followed by significant sustained weight loss and improved glucose homeostasis and satiation peptide responses. Weight loss following POSE may be mediated through changes in gastrointestinal neuro-endocrine physiology.

A randomized controlled study of neuromuscular electrical stimulation in oropharyngeal dysphagia secondary to acquired brain injury.

BACKGROUND AND PURPOSE: To evaluate the effectiveness of neuromuscular electrical stimulation (NMES) treatment in patients with oropharyngeal dysphagia secondary to acquired brain injury. METHODS: Twenty patients with neurological oropharyngeal dysphagia (14 stroke and six severe traumatic brain injury) were enrolled in a prospective randomized study, with patients and assessors blinded (to group allocation): 10 patients underwent NMES and conventional swallowing therapy and 10 patients underwent sham electrical stimulation (SES) and conventional swallowing therapy. Both groups completed 20 sessions. At baseline, at the end of treatment (1 month) and at 3-month follow-up, clinical, videofluoroscopic and esophageal manometric analyses were done. Feeding swallowing capacity was evaluated using the functional oral intake scale (FOIS). RESULTS: Mean FOIS score before treatment was 1.9 for the NMES group and 2.1 for the SES group. After treatment, the NMES group increased by 2.6 points (4.5 points) compared with only 1 point (3.1 points) for the SES group (P = 0.005). At 3 months of follow-up, mean scores were 5.3 and 4.6 respectively; thus, both groups improved similarly. At that time point (3 months), tracheal aspiration persisted in six patients in each group. However, a significant improvement in relation to the bolus viscosity at which aspiration appeared was found in the NMES group versus the SES group (P = 0.015). Also, a significant increase (P = 0.04) in pharyngeal amplitude contraction was observed at the end of treatment (1 month) in the NMES group compared with the SES group. CONCLUSION: Neuromuscular electrical stimulation significantly accelerated swallowing function improvement in patients with oropharyngeal dysphagia secondary to acquired brain injury.

Treatment for constipation: new and old pharmacological strategies.

BACKGROUND: Constipation is a very common entity. Despite the high prevalence, treatment of constipation remains problematic. PURPOSE: Review the current literature on new and existing constipation treatment modalities.

Botulinum toxin treatment for oropharyngeal dysphagia in patients with stroke.

BACKGROUND: In a previous pilot study, we demonstrated that a single injection of botulinum toxin A (BTX-A) in the cricopharyngeus muscle is effective in patients with neurologic dysphagia with upper esophageal sphincter (UES) opening dysfunction and presence of some pharyngeal contraction (>25 mmHg). The aim of this study was to confirm the long-lasting efficacy of this procedure after stroke. METHODS: We prospectively studied 23 patients with stroke for at least 6 months before administration of a BTX-A injection. Baseline diagnosis of UES opening dysfunction and presence of some pharyngeal contraction were assessed by videofluoroscopy (VFS) and esophageal manometry (EM). Clinical and VFS follow-up was made at 3 weeks and 3, 6, and 12 months postinjection. KEY RESULTS: Eighteen patients (78%) were fed by gastrostomy tube prior to treatment. Videofluoroscopy showed UES relaxation impairment, residue in pyriform sinuses, and aspiration in all cases. After BTX-A, the number of patients with aspiration and pharyngeal residue decreased to 52% and 70%, respectively (p < 0.05 for both); residue was severe in only 4%. Esophageal manometry showed a mean pharyngeal amplitude 66.8 mmHg (range: 25-120 mmHg). We observed a significant improvement in feeding mode during follow-up: after 3 months, 70% of patients were eating exclusively by mouth. Lower residual pressure and minor pharyngeal delay time at baseline were all predictive factors for treatment effectiveness. CONCLUSIONS & INFERENCES: A single injection of BTX-A is efficacious for a period of at least 12 months in improving oropharyngeal dysphagia in stroke patients with UES opening dysfunction and some pharyngeal contraction (>25 mmHg).

Effectiveness of chin-down posture to prevent tracheal aspiration in dysphagia secondary to acquired brain injury. A videofluoroscopy study.

BACKGROUND: The chin-down posture is generally recommended in patients with neurogenic dysphagia to prevent tracheal aspiration; however, its effectiveness has not been demonstrated. AIM: To videofluoroscopically (VDF) assess the effectiveness of chin-down posture to prevent aspiration in patients with neurogenic dysphagia secondary to acquired brain injury. METHODS: Randomized, alternating, cross-over study (with and without the chin-down posture) in 47 patients with a VDF diagnosis of aspiration [31 stroke, 16 traumatic brain injury (TBI)] and 25 controls without aspiration (14 stroke, 11 TBI). KEY RESULTS: During the chin-down posture, 55% of patients avoided aspiration (40% preswallow aspiration and 60% aspiration during swallow). The percentage was similar in both etiologies (58% stroke and 50% TBI). Fifty-one percent of patients had silent aspiration; of these, 48% persisted with aspiration while in the chin-down posture. A statistically significant relationship was found between the existence of pharyngeal residue, cricopharyngeal dysfunction, pharyngeal delay time and bolus volume with the persistence of aspiration. The chin-down posture did not change swallow biomechanics in patients without aspiration. CONCLUSIONS & INFERENCES: Only half the patients with acquired brain injury avoided aspiration during cervical flexion; 48% of silent aspirators continued to aspire during the maneuver. Several videofluoroscopic parameters were related to inefficiency of the maneuver. Therefore, the indication for chin-down posture should be evaluated by videofluoroscopic examination.

Severity in irritable bowel syndrome: a Rome Foundation Working Team report.

OBJECTIVES: The concept of severity in irritable bowel syndrome (IBS) is clinically recognized and operative in diagnostic decision making and treatment planning. Yet, there is no consensus on its definition, and there are limited data on the prevalence of severity subgroups, its medical and psychosocial determinants, and its association with other health status measures. The aims of the Rome Foundation Working Team Committee were to summarize current research, to develop a consensus of understanding on this concept, and to make recommendations for its use in research and clinical care. METHODS: In 2006, a multinational committee of clinical investigators with expertise in IBS and/or psychometric research methods undertook a systematic review of the literature relating to severity in IBS. Owing to limited data, the Foundation commissioned three clinical studies to better characterize the concept of severity in IBS, and summary information and recommendations for future research and clinical care were developed. RESULTS: The main findings were: (i) severity in IBS is defined as a biopsychosocial composite of patient-reported gastrointestinal and extraintestinal symptoms, degree of disability, and illness-related perceptions and behaviors; (ii) both visceral and central nervous system physiological factors affect severity; as severity increases, the central nervous system provides a greater contribution; (iii) severity is related to and influences health-related quality of life and health behaviors and also guides diagnostic and therapeutic clinical decision making; (iv) severity can be subcategorized into clinically meaningful subgroups as mild (∼40%), moderate (∼35%), and severe (∼25%), and this provides a working model for use in future research and clinical care. CONCLUSIONS: Future work is required to understand more precisely the factors contributing to severity and to develop a valid patient-reported instrument to measure severity in IBS.

Normal values in ambulatory oesophageal pH monitoring at two levels in Spain.

AIM: Upper oesophageal pH monitoring may play a significant role in the study of extra-oesophageal GERD, but limited normal data are available to date. Our aim was to develop a large series of normal values of proximal oesophageal acidification. METHODS: 155 healthy volunteers (74 male) participated in a multi-centre national study including oesophageal manometry and 24 hours oesophageal pH monitoring using two electrodes individually located 5 cm above the LOS and 3 cm below the UOS. RESULTS: 130 participants with normal manometry completed all the study. Twelve of them were excluded for inadequate pH tests. Twenty-seven subjects had abnormal conventional pH. The remaining 91 subjects (37 M; 18-72 yrs age range) formed the reference group for normality. At the level of the upper oesophagus, the 95th percentile of the total number of reflux events was 30, after eliminating the meal periods 22, and after eliminating also the pseudo-reflux events 18. Duration of the longest episodes was 5, 4 and 4 min, respectively (3.5 min in upright and 0.5 min in supine). The upper limit for the percentage of acid exposure time was 1.35, 1.05 and 0.95%, respectively. No reflux events were recorded in the upper oesophagus in 8 cases. CONCLUSION: This is the largest series of normal values of proximal oesophageal reflux that confirm the existence of acid reflux at that level in healthy subjects, in small quantity and unrelated to age or gender. Our data support the convenience of excluding pseudo-reflux events and meal periods from analysis.

Evolution of tracheal aspiration in severe traumatic brain injury-related oropharyngeal dysphagia: 1-year longitudinal follow-up study.

The aims of the article were to ascertain the clinical evolution and prognostic factors of aspiration recovery and feeding outcome in patients with severe traumatic brain injury (TBI) and a videofluoroscopic (VFS) diagnosis of tracheal aspiration. Twenty-six patients with severe TBI and VFS diagnosis of tracheal aspiration were prospectively evaluated. Clinical evaluation of oropharyngeal dysphagia and VFS examination were performed at admission and repeated at 1, 3, 6 and 12 months of follow-up. At admission, all patients had VFS aspiration. During follow-up, an improvement was observed in both oral and pharyngeal function, with the number of patients with aspiration decreasing progressively. The most significant change occurred in the examination made at 3 months. At 1 year, only 23% of patients had aspiration. No patient had clinically significant respiratory infections during the follow-up period. Persistent aspiration at 1 year of follow-up correlated with baseline variables: Rancho Los Amigos Level Cognitive Function Scale score, Disability Rating Scale score, tongue control alteration, velopharyngeal reflex abolition and delay in triggering swallowing reflex. Swallowing physiology in severe TBI greatly improved during follow-up and the number of aspirations decreased progressively, with the most significant reduction at between 3 and 6 months of evolution. This study revealed several prognostic factors for persisting aspiration: neurological involvement (evaluated with the Rancho Los Amigos Level Cognitive Function Scale and Disability Rating Scale), tongue control alteration, oropharyngeal reflex abolition and delay in triggering swallowing reflex at baseline.

[Videofluoroscopy quantification of laryngotracheal aspiration outcome in traumatic brain injury-related oropharyngeal dysphagia]. / Evolución de la aspiración laringo-traqueal en la disfagia orofaríngea secundaria a lesión cerebral traumática: cuantificación videofluoroscópica.

INTRODUCTION: Swallowing impairments are frequent after severe traumatic brain injury (TBI). OBJECTIVE: to define and prospectively quantify the videofluoroscopic symptoms in patients after TBI, and to evaluate the evolution of patients with laryngotracheal aspiration. METHOD: We studied 10 patients with TBI, and a clinical suspicion of aspiration confirmed by means of a videofluoroscopic exploration (VDF). VDF was repeated at 1, 3, 6, and 12 months thereafter. RESULTS: 30% of patients had an impaired gag reflex, and 40% cough during oral feeding. In the first VDF exploration the following was observed: increased oral transit time (OTT) in 70% (average: 3.8 sec.; range: 0.8-15 sec.), altered lingual control in 60%, and dysfunctional palatoglossal closure in 20%. Mean pharyngeal transit time (PTT) was 0.72 sec. (range: 0.34-1.50 sec.), and time to swallowing reflex (TSR) was 0.32 sec. (range: 0.10-0.80 sec.). After one year only 3 patients had aspiration--with a normal OTT in 7 patients, a normal PTT in 9, and a normal TSR in all; 80% had an exclusively oral diet, and 20% combined oral intake and gastrostomy feeding. CONCLUSION: Videofluoroscopic evaluation allows to confirm and quantite swallowing dysfunction in patients with severe TBI. Most frequent early findings included an increase in OTT and alterations in lingual control; aspirations were quite frequent, and more than half were silent. After one year the majority of patients showed a favorable outcome.

Change over time of bowel habit in irritable bowel syndrome: a prospective, observational, 1-year follow-up study (RITMO study).

BACKGROUND: Evolution of bowel habit in irritable bowel syndrome (IBS) is not well known. AIM: To evaluate the change over time of bowel habit in IBS patients followed-up during 1 year. METHODS: Five hundred and seventeen patients with IBS were prospectively included in an observational study with five evaluations over a 1-year period. Symptoms were recorded daily in diary cards during four 4-week periods along the study. Bristol Stool Scale (BSS) was used to define bowel habit. RESULTS: Four-hundred patients completed the study. Rome II showed low-moderate agreement (42%) with BSS to define bowel habit. Frequency of constipation and diarrhoea showed little changes throughout the study. Over 50% of the patients had the same bowel habit when each diary was compared with the next one. A third of patients maintained the same habit throughout the study. Most changes occurred from/to mixed or unsubtyped IBS. Only 14% of cases changed from constipation to diarrhoea or vice versa. This change was associated to female gender (OR: 2.65). CONCLUSIONS: The frequency of constipation and diarrhoea remains relatively stable over time. Changes in IBS subtypes are common, but changes between constipation and diarrhoea are rare. Alternating IBS is more frequent in women.

Irritable bowel syndrome: the burden and unmet needs in Europe.

Irritable bowel syndrome affects approximately 10-15% of the European population, although prevalence rates vary depending on the classification used and the country surveyed. This may be due to differences in patterns of medical care and diagnosis of the condition. Up to 70% of individuals with irritable bowel syndrome may not have been formally diagnosed. The disorder affects 1.5-3 times as many women as men and poses a significant economic burden in Europe, estimated at euro 700-euro 1600 per person per year. It also reduces quality of life and is associated with psychological distress, disturbed work and sleep, and sexual dysfunction. It is a chronic disorder, which affects many individuals for more than 10 years. Most patients are managed in primary care, although some are referred to gastroenterologists and other specialists. Patients with irritable bowel syndrome undergo more abdomino-pelvic surgery than the general population. We propose that a positive diagnosis of the condition may avoid the delay in diagnosis many patients experience. We conclude that, in Europe, there are significant unmet needs including lack of familiarity with irritable bowel syndrome, difficulties in diagnosis and lack of effective treatments for the multiple symptoms of the disorder. The development of pan-European guidelines for irritable bowel syndrome will benefit patients with this condition in Europe.

Intramuscular interstitial cells of Cajal associated with mast cells survive nitrergic nerves in achalasia.

Achalasia is dominated by injury to inhibitory nerves. As intramuscular interstitial cells of Cajal (ICC-IM) are proposed to form functional units with nitrergic nerves, their fate in achalasia may be critically important. We studied the relationship between loss of nitrergic nerves and injury to ICC-IM in patients with achalasia and determined associations between ICC-IM and mast cells (MC), using quantitative immunohistochemistry and electron microscopy. Loss of neuronal nitric oxide synthase (nNOS) immunoreactivity was completed within 3 years of acquiring achalasia. Thereafter, progressive ultrastructural injury to remaining nerve structures was evident. Within the first 2 years, the number of ICC-IM did not decline although ultrastructural injury was already present. Thereafter, loss of ICC-IM occurred unrelated to duration of disease. Damage to ICC-IM appeared unrelated to nerve injury. A significant MC infiltration was observed in the musculature; the number of MC was positively related to the persistent number of ICC-IM. Mast cell formed close contacts with ICC-IM and piecemeal-degranulation occurred towards ICC-IM. In conclusion, injury to ICC-IM in achalasia is variable, but not related to duration of disease and injury to nitrergic nerves. MC are prominent and form close functional contact with ICC-IM which may be responsible for their relatively long survival.

Predictive factors of irritable bowel syndrome improvement: 1-year prospective evaluation in 400 patients.

BACKGROUND: The natural history of the irritable bowel syndrome is poorly understood. AIM: To assess the clinical course of the irritable bowel syndrome and the factors that might predict it. METHODS: An observational prospective study, involving 400 irritable bowel syndrome patients meeting Rome II criteria. Symptoms were recorded in a diary over four non-consecutive months (1, 4, 7 and 10). Demographic data, associated disorders, psychological status and health-related quality of life were obtained. RESULTS: At 1-year follow-up, half of the patients and half of their physicians considered irritable bowel syndrome to have improved, but improvement was minor. Diary data showed that, according to the type of symptom, improvement was small and quite different: diarrhoea in 19% of patients, abdominal pain frequency in 26%, constipation in 33% and abdominal pain intensity in 60%. Factors related to improvement at one year were: severe symptoms and poor health-related quality of life at first visit, irritable bowel syndrome-constipation, good improvement at 3 months, anxiety/depression, stress, symptoms related to meals and absence of comorbidity. By multivariate logistic regression, predictors were: severe basal symptoms and good improvement at 3 months (OR:CI 95%, 1.32:1.09-1.59 and 4.44:2.81-7.05). CONCLUSIONS: At 1-year follow-up, half the patients and their physicians considered the irritable bowel syndrome to have had some improvement but, symptom diaries demonstrated that improvement was small and heterogeneous. Severe basal symptoms and improvement at 3 months were related to better prognosis.