Chronic nausea and vomiting: insights into underlying mechanisms.

Chronic nausea and vomiting are common and debilitating symptoms in adults. There are some fundamental problems that make our understanding of mechanisms difficult, diagnostic definitions of patient-cohorts being central. As there is no unifying mechanism with a direct link to chronic nausea or vomiting, it is most likely that several mechanisms interact, e.g., pylorus function and its relation to gastric emptying, or gastric sensory and motor function. In this mini-review, we highlight the roles and evidence for brain-gut interactions as well as gastrointestinal neurophysiologic, motor, sensory, and hormonal factors involved in the pathophysiology of chronic nausea and vomiting. There are factors not mentioned in the text, mostly as they are not well characterized in the setting of chronic symptoms or only in animal models.

Measurement of gastric emptying by radiopaque markers in patients with diabetes: correlation with scintigraphy and upper gastrointestinal symptoms.

BACKGROUND: Scintigraphy, the gold standard to measure gastric emptying, is expensive and not widely available. Therefore, we compared emptying of radiopaque markers (ROM) from the stomach, by use of fluoroscopy, with scintigraphy in patients with insulin-treated diabetes. METHODS: On the same day we measured gastric emptying of 20 ROM using fluoroscopy and scintigraphic emptying of a standard solid meal. The subjects also completed a validated gastrointestinal (GI) symptom questionnaire. KEY RESULTS: We included 115 patients with insulin-treated diabetes (median age 53, range 21-69 years; 59 women). A moderately strong correlation was demonstrated between scintigraphic (% retained at 2 h) and ROM emptying (markers retained at 6 h) (r = 0.47; P < 0.0001). Eighty-three patients had delayed gastric emptying with scintigraphy, whereas only 29 patients had delayed emptying of ROM. Of the 29 patients with delayed emptying of ROM, 28 also had delayed scintigraphic emptying. The sensitivity and specificity of the ROM test was 34% and 97%, respectively. Significant correlations were only noted between scintigraphic gastric emptying and GI symptom severity, with the strongest correlations for fullness/early satiety (r = 0.34; P < 0.001) and nausea/vomiting (r = 0.30; P < 0.001). CONCLUSIONS & INFERENCES: A gastric emptying test with ROM is a widely available screening method to detect delayed gastric emptying in patients with diabetes, where a positive result seems reliable. However, a normal ROM test does not exclude delayed gastric emptying, and if the clinical suspicion of gastroparesis remains, scintigraphy should be performed. Results from scintigraphy also correlate with GI symptom severity, which ROM test did not.

Patient satisfaction after gut-directed hypnotherapy in irritable bowel syndrome.

BACKGROUND: Gut-directed hypnotherapy is an effective treatment option for irritable bowel syndrome (IBS). However, clinical observations suggest that patient satisfaction with hypnotherapy is not always associated with improvement in IBS symptoms. METHODS: We evaluated 83 patients with IBS treated with gut-directed hypnotherapy (1 h week(-1), 12 weeks). After the treatment period, patients reported their satisfaction with the treatment (ranging from 1 = not at all satisfied, to 5 = very satisfied) and completed questionnaires to assess IBS symptom severity, quality of life, cognitive function, sense of coherence, depression, and anxiety before and after treatment. KEY RESULTS: After hypnotherapy improved IBS symptom severity, quality of life, cognitive function, and anxiety were seen. Thirty patients (36%) were very satisfied with the treatment and 57 (69%) patients scored 4 or 5 on the patient satisfaction scale. Patient satisfaction was associated with less severe IBS symptoms and better quality of life after the treatment. In a multiple linear regression analysis, only the quality of life domain sexual relations was independently associated with patient satisfaction after hypnotherapy, explaining 22% of the variance. Using 25% reduction of IBS symptom severity to define an IBS symptom responder, 52% of the responders were very satisfied with hypnotherapy, but this was also true for 31% in the non-responder group. CONCLUSIONS & INFERENCES: Patient satisfaction with gut-directed hypnotherapy in IBS is associated with improvement of quality of life and gastrointestinal (GI) symptoms. However, other factors unrelated to GI symptoms also seems to be of importance for patient satisfaction, as a substantial proportion of patients without GI symptom improvement were also very satisfied with this treatment option.

Randomised clinical trial: The ileal bile acid transporter inhibitor A3309 vs. placebo in patients with chronic idiopathic constipation--a double-blind study.

BACKGROUND: One half of patients with constipation are not satisfied with available therapies, hence there is a need for more effective and well-tolerated drugs. AIM: To evaluate the effects of a specific inhibitor of the Ileal Bile Acid Transporter (IBAT; syn apical sodium-dependent bile acid transporter; ASBT) in patients with chronic idiopathic constipation (CIC) with focus on safety, colonic transit and efficacy signals. METHODS: This was a single-centre, prospective, randomised, double-blind, placebo-controlled study with a dose-escalating design in patients with CIC. In addition to evaluation of conventional safety and tolerability parameters, (i) colonic transit time (CTT) was measured using radio-opaque markers, (ii) metabolic parameters [lipid profile, C4 (7α-hydroxy-4-cholesten-3-one) and FGF19 (Fibroblast Growth Factor 19)] were evaluated, and (iii) constipation parameters, such as changes in stool frequency and consistency, were analysed. RESULTS: Thirty patients were randomised into five dose-levels (range: 0.1-10 mg/day) or to placebo. All patients completed a 14-day treatment period, and the safety/tolerability analysis was favourable. A3309, present in picomolar concentrations in plasma, induced up to a three-fold increase in bile acid synthesis (C4) and a reduction of plasma FGF19, as well as reduction in total and LDL cholesterol. CTT was reduced in the highest dose groups; the main acceleration was identified in the left colon. Efficacy parameters showed trends for increased number of spontaneous bowel movements and improved stool consistency. CONCLUSIONS: Ileal Bile Acid Transporter inhibition is a novel mechanism for treatment of patients with chronic idiopathic constipation and has additional benefits of improving metabolic parameters (EudraCT 2008-003255-72).

Familial intestinal degenerative neuropathy associated with chronic intestinal pseudo-obstruction.

BACKGROUND: Few families with autosomal dominant forms of chronic idiopathic pseudo-obstruction (CIP) have been identified and reported. METHODS: We compared two families by clinical, laboratory, histopathologic, and genealogical investigations. Ten patients (pts) (five women) from two families, A and B, both with a family history suggesting autosomal dominant CIP, were investigated. KEY RESULTS: All pts had chronic diarrhea, nine of ten pts had chronic abdominal pain and seven of ten chronic vomiting. Median age for onset of symptoms was 23 (A) and 34 years (B). None had dysphagia, urogenital, neurologic, or ocular symptoms. Small bowel transit and jejunal culture were abnormal in eight of nine. Manometry showed severe jejunal hypomotility in the fasting and fed state and absence of normal phase III in all nine pts and neuropathy-like duodenal alterations in eight of nine. Progress to overt CIP had occurred in six pts. Histopathologic re-evaluation (three pts) showed that criteria of visceral degenerative neuropathy were fulfilled in both families including intranuclear inclusions in all three pts. Genealogic exploration using the unique Swedish Register for Catechetical Meetings disclosed that the two families with all likelihood shared a male ancestor in the 1890 s. CONCLUSIONS & INFERENCES: The compiled results with striking similarities between family A and B together with genealogy findings indicate that this is one, large kindred with a familial autosomal dominant form of intestinal degenerative neuropathy often progressing to CIP but without extra-intestinal manifestations. This is the fourth and, so far, the largest family reported with these characteristics.

Temporary percutaneous gastric electrical stimulation: a novel technique tested in patients with non-established indications for gastric electrical stimulation.

AIM: To test temporary percutaneous gastric electrical stimulation (TPGES) in patients with drug-refractory nausea/vomiting and nonestablished indications for GES. METHODS: 27 patients (2-81 years) underwent TPGES with electrodes implanted at gastroscopy and received stimulation for 7-21 days with low current settings (5-7 mA) either as open stimulation (n = 14) or randomized to double-blind crossover stimulation (n = 13; ON for 12-14 days, OFF for 12-14 days). Symptoms were recorded daily. Nonresponders were offered another period (14-21 days) with increased stimulation (8-10 mA). RESULTS: Mean lead implantation time was 14 min. Leads were kept implanted for ≤60 days. 22 of 27 evaluable patients had a favorable symptom reduction, preferentially of nausea/vomiting, irrespective of delayed or normal gastric emptying rate: postsurgical gastroparesis 7/8, chronic intestinal pseudo-obstruction 2/2, idiopathic gastroparesis 1/1, functional dyspepsia 6/9, diabetes mellitus 2/2, postsurgical nausea/vomiting 2/2, malformation syndrome 1/1, intestinal neuropathy 1/1, intestinal interstitial cells of Cajal deficiency 0/1. 6 patients had a clear symptom reduction during the ON period compared with stimulation OFF. Four of 7 patients improved with increased stimulation (8-10 mA). Twenty of the 22 responders received a permanent GES implant, 90% of them still being responders at last follow-up. CONCLUSION: TPGES seems promising to study new indications for GES and to select responders/non-responders.

Accuracy in assessment of colonic transit time with particles: how many markers should be used?

BACKGROUND: Colonic transit time (CTT) is often measured with particle methods in clinical practice, but few studies have evaluated the role of particle amounts for the results obtained. METHODS: Colonic transit time was studied in 28 subjects taking radiopaque particles for six consecutive days followed by an abdominal radiograph on day 7. Four distinguishable marker types were ingested simultaneously in an amount of 5, 10, 15, and 20 daily, respectively, and CTT calculated for each type as the number of retained markers divided by the daily intake. Reference values were based on 50 markers daily. KEY RESULTS: Accuracy measured as median deviation of CTT from reference was for 20 markers day(-1) 0.08 days, for 15 markers day(-1) 0.10 days, for 10 markers day(-1) 0.12 days, and for 5 markers day(-1) 0.20 days. The CTT values obtained with 5 markers day(-1) deviated significantly more from the reference value than CTT values obtained with 10 markers day(-1) (P < 0.05) and with 15 and 20 markers day(-1) (P < 0.01). Colonic transit times obtained with 20, 15, or 10 markers day(-1) did not differ significantly (P > 0.1). CONCLUSIONS & INFERENCES: Colonic transit time can be assessed with reasonable accuracy after repeated ingestion of particles. For clinical use, a daily amount of 10 or 12 markers is proposed for reporting CTT in days or hours, respectively. Doses below 10 daily yield a steeply increasing deviation from reference values.

Predictors of subjective fatigue in chronic gastrointestinal disease.

BACKGROUND: Fatigue is a common, but poorly understood symptom in patients with chronic gastrointestinal (GI) diseases. AIM: To evaluate factors of importance for fatigue in patients with chronic GI diseases, and to compare it with fatigue in the general population. METHODS: In all, 399 patients attending a GI out-patient clinic completed questionnaires assessing fatigue, sleep disturbances, psychological general well-being and GI symptom severity. The patients were divided into two diagnostic groups: functional GI disorders (n = 112) and organic GI diseases (n = 287). The severity of fatigue was also evaluated in an age- and gender-matched group of 399 individuals from the general population. RESULTS: Both patient groups had more severe fatigue than controls and patients with functional GI disorders were more fatigued than patients with an organic GI disease. Fatigue was associated with psychological general well-being, GI symptom severity, gender, employment status and sleep disturbances. In a linear regression analysis, psychological general well-being (vitality, general health, self-control), sleep disturbances and employment status were independently associated with the severity of fatigue (adjusted R(2) = 55%). CONCLUSIONS: Fatigue is a troublesome symptom in a subgroup of patients with chronic GI diseases. These patients have a high symptom burden as regards both GI and psychological symptoms, as well as sleep disturbances.

Gastrointestinal transit abnormalities are frequently detected in patients with unexplained GI symptoms at a tertiary centre.

The aim of this prospective study was to analyse the yield and utility of a gastrointestinal (GI) transit measurement procedure in clinical practice. Patients referred by gastroenterologists to a tertiary centre for detailed transit measurements were prospectively included. All together 243 patients were enrolled. Body mass index was recorded. The patients were categorized according to the predominant symptom into five groups: diarrhoea, constipation, nausea, vomiting and abdominal pain. The patients recorded their bowel movements and GI symptoms daily during the week before the transit measurement. Percentiles 5 and 95 of the transit values in 83 healthy subjects served as reference values. Widespread abnormalities were found in the five patient groups and 63% of the patients had at least one transit abnormality. The abnormalities were more frequent in men compared with women. Patients with underweight had more motility disturbances compared with other patients. In male and female patients with vomiting a significant delay of transit in the ascending colon was observed compared with healthy subjects. Large-scale transit measurements frequently detect transit abnormalities in clinical practice and may elucidate the relationship between some GI symptoms and abnormal motility.

Subtyping the irritable bowel syndrome by predominant bowel habit: Rome II versus Rome III.

BACKGROUND: The agreement between subtyping irritable bowel syndrome (IBS) patients based on Rome II criteria versus Rome III criteria is unknown. AIM: To compare IBS subtyping based on Rome II versus III criteria. METHODS: The Rome II Modular Questionnaire and the Bristol Stool Form Scale (one-week diary cards) were completed by 249 IBS patients. Based on the Rome II criteria, patients were defined as having diarrhoea- or constipation-predominant IBS, or alternating IBS. Based on the Rome III criteria, patients were divided into IBS with constipation, IBS with diarrhoea, mixed IBS or unsubtyped IBS. Agreement between Rome II and Rome III was assessed with kappa statistics. RESULTS: Based on Rome II there were 92 diarrhoea-predominant IBS, 45 constipation-predominant IBS and 112 alternating IBS, and based on Rome III 97 IBS with diarrhoea, 77 IBS with constipation, 16 mixed IBS and 59 unsubtyped IBS. The agreement between Rome II and Rome III subgroups was 46% (kappa = 0.19). Changes from the constipation to the diarrhoea subgroups and vice versa were uncommon (8% of patients). The majority of changes occurred from/to the alternating IBS, mixed IBS and unsubtyped IBS subgroups. CONCLUSION: There is poor agreement between subtyping of IBS patients based on Rome II versus Rome III criteria.

Nutritional aspects in patients with functional gastrointestinal disorders and motor dysfunction in the gut. Working team report of the Swedish Motility Group (SMoG).

In reviews regarding the management of patients with functional gastrointestinal disorders and motility disturbances within the gut nutritional aspects and dietary advice is often put forward as being of great importance. However, there are relatively few high-quality, interventional studies in the literature supporting an important role for general dietary advice to improve symptoms in these patients. Nutritional supplementation to patients with malnutrition due to severe dysfunction of the gastrointestinal tract is of course less controversial, even though different views on how this should be performed exist. The content of this article is based on presentations given by the authors during the second meeting of the Swedish Motility Group held in Gothenburg in March 2005, and aims to give an overview on the role of dietary advice and nutritional supplementation to patients with gastrointestinal dysfunction of different severity.

Percutaneous implantation of gastric electrodes - a novel technique applied in animals and in patients.

Temporary electrodes implanted under general anaesthesia, or via an oral or percutaneous endoscopic gastrostomy route have been used for testing of gastric electrical stimulation (GES). We have developed a principle for percutaneous electrode implantation. Leads were constructed so that the tip could be anchored to the gastric submucosa under gastroscopic control. Acute experiments were performed in anaesthetized pigs. Three patients referred for nausea and/or vomiting and non-established indications for GES (chronic intestinal pseudo-obstruction, functional dyspepsia without gastroparesis) were evaluated. Electrode function was tested by recording and stimulation techniques. In the pigs, a slow-wave (SW) rhythm (3 min(-1)) was recorded with decrease in frequency at the end of the experiments. In the patients, implantation time from start of gastroscopy to end of electrode placement was 12-20 min. Electrode distance varied from 12 to 45 mm. Gastric electromyography showed a regular SW rhythm of about 3 min(-1). Antral pressure waves had intervals being multiples of the SW-to-SW time. With temporary GES for 7-9 days, weekly frequency of the referral symptoms decreased >80% in two patients and 33% in one patient. Temporary percutaneous gastric leads can easily be implanted and may be used for testing of GES and study of gastric electrophysiology.

Nutrient-dependent enhancement of rectal sensitivity in irritable bowel syndrome (IBS).

Food-related gastrointestinal symptoms are common in irritable bowel syndrome (IBS), but the mechanisms behind this are unclear. Enhanced colorectal sensitivity after duodenal lipid administration in IBS patients has been demonstrated. However, the effects of a regular meal on colorectal sensitivity in these patients and the importance of the composition of the meal are not known. On two separate days, 10 IBS patients and 11 controls randomly received a liquid meal (800 kcal), containing 60% calories from fat (fatty meal) or carbohydrate (carbohydrate meal). Using a barostat rectal sensitivity was assessed during four separate distension sequences before, immediately after and 30 and 60 min after the meal. In the patients, the discomfort (P = 0.04) and the pain thresholds (P = 0.007) were gradually reduced after the fatty meal, whereas only a tendency in the same direction was seen after the carbohydrate meal. In patients VAS ratings for pain increased after the fatty meal (P = 0.03), but not after carbohydrates. In the controls, sensory thresholds were not affected by the meals. In IBS, a liquid meal enhances rectal sensitivity, and this seems to be partly nutrient dependent as a fatty meal has more pronounced effects than a carbohydrate meal. This might be of relevance for their postprandial symptoms.

Discontinuation of proton pump inhibitors in patients on long-term therapy: a double-blind, placebo-controlled trial.

BACKGROUND: The proportion of proton pump inhibitor users on long-term therapy who can discontinue proton pump inhibitor (PPI) medication without developing symptoms is unknown. AIM: To determine the proportion of patients on long-term PPI therapy who are able to discontinue PPIs without developing symptoms. METHODS: Patients on long-term PPIs, without a history of peptic ulcer or esophagitis underwent upper endoscopy. Patients were randomized double-blindly to taper down or continue a constant dosage of omeprazole for three weeks. Thereafter, all patients discontinued PPIs. RESULTS: Of the 97 patients enrolled, had used PPIs for 48 months, 78% had GERD. A total of 27% did not use PPIs during the year after discontinuation, 31% of the patients randomized to tapering discontinued PPIs and 22% of those who did not could discontinue therapy (NS). Gastro-oesophageal reflux disease (GERD) patients were more prone to continue PPIs than non-GERD patients. Only 16 (21%) of GERD patients were off PPIs vs. 48% of patients without GERD (p < 0.05). Serum gastrin was higher at baseline in GERD patients who resumed PPIs versus non-resumers (p < 0.05). GERD and serum gastrin were independent predictors of PPI requirement. CONCLUSIONS: Discontinuation of PPI was successful in 27% of long-term PPI users. GERD patients had more difficulty discontinuing PPIs than non-GERD patients.

Gastric electrical stimulation for intractable vomiting in patients with chronic intestinal pseudoobstruction.

Gastric electrical stimulation (GES) is effective for medically refractory nausea and vomiting in patients with idiopathic or diabetic gastroparesis (DGP). We studied whether GES has similar effects in chronic intestinal pseudoobstruction (CIP). Patients referred for chronic small bowel (SB) motor dysfunction requiring parenteral nutrition and having a weekly vomiting frequency (WVF) >/=7 refractory to prokinetics and antiemetics were included. Patients were implanted for high-frequency GES 12 stimuli min(-1), laparoscopy being the first-line implantation procedure. Results were compared with those obtained in 11 DGP patients. Three patients with familial CIP and one patient with postsurgical CIP fulfilled the criteria. Gastric emptying was delayed in two and was normal in two patients. SB transit time was markedly delayed. Laparoscopy was used in three patients, one patient required laparotomy. During GES, WVF decreased from 24 (mean) before GES to 6.9 at 12 months and 7.5 at last visit. Vomiting reduction was 50-90% at last visit. For the DGP patients, WVF decreased from 23 before GES to 3.5 at 12 months and 3.5 (P < 0.01) at last visit. In patients with CIP and medically refractory vomiting, GES seems to have an anti-vomiting effect comparable to that seen in patients with severe DGP. GES should be considered as a therapeutic option for these patients.

High interdigestive and postprandial motilin levels in patients with the irritable bowel syndrome.

Motilin shows cyclic variation with the different phases of the migrating motor complex (MMC). Altered motilin levels have been found in irritable bowel syndrome (IBS) patients, but in these studies motilin levels were analysed without the knowledge of the phases of MMC. We included 13 healthy controls (HC) and 24 patients with IBS [12 diarrhoea-predominant (IBS-D) and 12 constipation-predominant (IBS-C)]. We performed interdigestive and postprandial antroduodenojejunal manometry and blood samples for analysis of motilin were drawn. Group differences in plasma levels of motilin were analysed during mid-phase II, just before the start of phase III (pre-III), during phase I, immediately before the meal and 30 and 60 min after the 500 kcal mixed meal. Higher motilin levels were observed in IBS vs HC in both the interdigestive and postprandial periods (P < 0.05). No significant differences between IBS-C and IBS-D were observed. The cyclic variation of motilin during MMC and the meal response was similar in IBS and controls. IBS patients, irrespective of the predominant bowel habit, demonstrate higher motilin levels than HCs in all phases of the MMC and also after a meal. These findings may bear some pathophysiological importance in IBS and relate to the gastrointestinal dysmotility often seen in these patients.

Altered visceral perceptual and neuroendocrine response in patients with irritable bowel syndrome during mental stress.

BACKGROUND AND AIMS: Stress often worsens the symptoms of irritable bowel syndrome (IBS). We hypothesised that this might be explained by altered neuroendocrine and visceral sensory responses to stress in IBS patients. SUBJECTS AND METHODS: Eighteen IBS patients and 22 control subjects were assessed using rectal balloon distensions before, during, and after mental stress. Ten controls and nine patients were studied in supplementary sessions. Rectal sensitivity (thresholds and intensity-visual analogue scale (VAS)) and perceived stress and arousal (VAS) were determined. Plasma levels of corticotropin releasing factor (CRF), adrenocorticotropic hormone (ACTH), cortisol, noradrenaline, and adrenaline were analysed at baseline, immediately after stress, and after the last distension. Heart rate was recorded continuously. RESULTS: Thresholds were increased during stress in control subjects (p<0.01) but not in IBS patients. Both groups showed lower thresholds after stress (p<0.05). Repeated distensions without stress did not affect thresholds. Both groups showed increased heart rate (p<0.001) and VAS ratings for stress and arousal (p<0.05) during stress. Patients demonstrated higher ratings for stress but lower for arousal than controls. Basal CRF levels were lower in patients (p<0.05) and increased significantly during stress in patients (p<0.01) but not in controls. Patients also responded with higher levels of ACTH during stress (p<0.05) and had higher basal levels of noradrenaline than controls (p<0.01). Controls, but not patients, showed increased levels of adrenaline and noradrenaline in response to stress (p<0.05). CONCLUSIONS: Stress induced exaggeration of the neuroendocrine response and visceral perceptual alterations during and after stress may explain some of the stress related gastrointestinal symptoms in IBS.

Delay in gastric emptying in patients with chronic renal failure.

BACKGROUND: Gastrointestinal (GI) symptoms are common in patients with chronic renal failure (CRF). Delayed gastric emptying might be a possible pathophysiological mechanism. The aims of this study were to evaluate gastric emptying in patients with CRF and to correlate the findings with GI symptoms and evaluate the impact of Helicobacter pylori infection in CRF patients on gastric emptying. METHODS: Thirty-nine patients with CRF (17 F, 22 M) were compared with 131 healthy subjects (74 F, 57 M). A standardized breakfast was given with 20 spherical, radiopaque markers (ROMs). The emptying was followed by fluoroscopy after 4, 5 and 6 h. Gastric emptying was assessed by calculating the individual mean percentual gastric retention of markers, 4 to 6 h after the meal. The perceived severity of GI symptoms was assessed with a validated questionnaire. Because of gender differences in gastric emptying, men and women were compared separately and a percentile of 95 was chosen as the upper reference value. H. pylori infection was assessed using a serological method. RESULTS: Delayed gastric emptying was found in 14 out of 39 (36%) of the CRF patients. There was no relationship between delayed gastric emptying and age, GI symptoms, H. pylori infection or underlying renal disease. However, a higher proportion of patients in peritoneal dialysis demonstrated delayed gastric emptying compared with predialytic patients (6 of 9 versus 2 of 13, P = 0.026). Men with CRF had a higher gastric retention compared with healthy men (16.6 (0-63.3)% versus 0 (0-2.1)%, P < 0.0001), and 10 men with CRF had delayed gastric emptying (P < 0.0001). There was no significant difference in mean gastric retention between women with CRF and healthy women (13.3 (0-55.4)% versus 10.8 (0-30.0)%, P = 0.93), but 4 women with CRF had delayed gastric emptying (P = 0.02). Eighteen of the CRF patients had GI symptoms (6 F, 12 M) and 21 were asymptomatic (11 F, 10 M). There was no difference in mean gastric retention in patients with CRF with and without GI symptoms (M: 13.3 (0-55.0)% versus 47.5 (5.0-65.0)%, P = 0.51, F: 16.6 (0-63.3)% versus 13.3 (0-59.2)%, P = 0.96). Gastric emptying in CRF patients with and without H. pylori infection showed no difference. CONCLUSIONS: Delayed gastric emptying is common in patients with chronic renal failure, particularly in men. The delay was not associated with the presence of GI symptoms, underlying renal disease or H. pylori infection. However, the dialytic status might have an impact on gastric emptying in patients with CRF.

Oxytocin stimulates colonic motor activity in healthy women.

The effects of oxytocin in the gastrointestinal tract are unclear. The aim of this study was to examine the effect of infusion of oxytocin on colonic motility and sensitivity in healthy women. Fourteen healthy women were investigated twice. A 6-channel perfusion catheter, with three recording points (2 cm apart) proximally and three recording points distally to a barostat balloon, was inserted to the splenic flexure. An intestinal feeding tube was placed in the mid-duodenum. A 90-min duodenal lipid infusion of 3 kcal min(-1) was administered. Thirty minutes after the start of the lipid infusion, the subject randomly received either 20 or 40 mU min(-1) of oxytocin, or isotonic saline as intravenous infusions for 90 min. Meanwhile, the colonic motility was recorded. During the last 30 min of oxytocin and saline infusion, the visceral sensitivity to balloon distensions was examined. During lipid infusion the number of antegrade contractions per hour was 0.7 +/- 0.3 after saline and 3.9 +/- 1.4 after oxytocin (P = 0.03), indicating more pronounced lumen-occlusive contractile activity after oxytocin administration. Some of these consisted of high-amplitude (> 103 mmHg in amplitude) antegrade contractions. Lipid infusion evoked a decrease of the balloon volume, reflecting increased colonic tone, but there was no difference between saline and oxytocin. Sensory thresholds did not differ significantly between saline and oxytocin. Infusion of oxytocin stimulates antegrade peristaltic contractions in stimulated colon in healthy women. The effects of oxytocin on colonic motor activity deserve to be further explored, especially in patients with colonic peristaltic dysfunction.