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Biomedical subjects

H Abrahamsson

Publications and source records attributed to H Abrahamsson.

At least 19 recordsLinked to original sources

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.

Adult↗

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.

Aged↗

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.

Adult↗

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.

Adult↗

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.

Adult↗

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.

Adult↗

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.

Adrenocorticotropic Hormone↗

Gastric emptying after autologous haemopoietic stem-cell transplantation: a prospective trial.

Gastroparesis may be involved in the pathophysiology of prolonged nausea and vomiting after haemopoietic stem-cell transplantation (HSCT), but this has not been prospectively investigated. Gastric emptying (GE) was investigated in 20 patients before and 2 months after autologous HSCT. Gastrointestinal symptoms were graded prospectively and oral energy intake was recorded in parallel. Before transplant, all patients were asymptomatic and GE was within the reference range. Post transplant GE was delayed in three patients and three patients reported nausea and/or vomiting. Neither gastrointestinal symptoms nor oral energy intake post transplant discriminated between patients with or without delayed GE. Oral energy intake before transplant was lower (P=0.05), and there was a greater need for total parenteral nutrition (TPN) among patients who developed gastroparesis post transplant (P<0.05). Delayed GE after HSCT was found to be less common than had been believed from retrospective studies. Gastroparesis may be involved in some cases of prolonged nausea and vomiting after autologous HSCT but alternative explanations should be considered. Symptoms consistent with gastroparesis did not correlate with GE. Patients at risk of developing gastroparesis may be found among those with nutritional difficulties before and during the transplant course.

Adult↗

Lipid-induced colonic hypersensitivity in irritable bowel syndrome: the role of 5-HT3 receptors.

BACKGROUND: Irritable bowel syndrome patients demonstrate colonic hypersensitivity after duodenal lipid infusion. AIM: To investigate the role of 5-hydroxytryptamine-3 (5-HT3) receptors in this sensory component of the gastrocolonic response in irritable bowel syndrome. METHODS: Fifteen female patients with diarrhoea-predominant irritable bowel syndrome completed a trial with the 5-HT3 receptor antagonist alosetron (1 mg b.d.) or placebo (b.d.) over 15 days, followed by the alternative treatment. Each treatment period was followed by a colonic distension trial before and after duodenal lipids. Changes in colonic thresholds, tone and compliance and viscerosomatic referral pattern after lipids were compared between treatments. RESULTS: With placebo, the colonic thresholds after lipids were significantly reduced for all studied sensations, whereas, with alosetron, the thresholds were significantly reduced only for first sensation and discomfort, but not for gas and pain. The reductions in thresholds did not differ significantly between treatments, but the pain threshold after alosetron tended to be less reduced compared with placebo (P = 0.10). The effects of lipids on tone, compliance and viscerosomatic referral pattern were unaffected by alosetron relative to placebo. CONCLUSIONS: 5-HT3 receptor antagonism reduces the lipid-induced colonic hypersensitivity in irritable bowel syndrome. However, 5-HT3 receptors do not seem to be the principal mediator, but may be a cofactor for the exaggerated sensory component of the gastrocolonic response in irritable bowel syndrome.

Adult↗

Gender differences in gut transit shown with a newly developed radiological procedure.

BACKGROUND: Gut transit measurements are essential for understanding the pathophysiology of many gastrointestinal disorders. The ideal bowel transit test should be easy to perform, widely accessible, reproducible, non-invasive and inexpensive and the risks should be minimal. These requirements prompted us to develop a procedure for simultaneous measurement of gastric emptying, small-bowel transit and colonic transit at one visit. We assessed the influence of gender, body mass index, age, menopause and smoking on gastrointestinal transit in healthy subjects. METHODS: Eighty-three healthy subjects (43 women) were included. Colonic transit was based on 10 radiopaque rings given daily for 6 days with fluoroscopy on day 7. Then, the subjects had a test meal containing 20 radiopaque markers. Using fluoroscopy, gastric emptying and small-bowel transit of the markers were followed until they reached the colon. RESULTS: Gastric emptying, small-bowel transit and colonic transit were significantly slower in female healthy subjects compared to males (2.9 (1.6-4.9) h, median and percentile 10-90, versus 2.4 (0.7-3.7) h, P=0.005; 4.4 (2.1-11.1) h versus 3.2 (1.5-6.0) h, P=0.001; 1.5 (1.0-3.7) days versus 1.3 (0.8-1.9) days P=0.002), respectively. Small-bowel transit was significantly faster in women with overweight and in postmenopausal women compared to lean and premenopausal women, respectively. CONCLUSION: This procedure meets most of the requirements of the ideal bowel transit test and is easily performed at one visit. Small-bowel transit as well as gastric emptying and colonic transit were significantly slower for women.

Adolescent↗

Etiology of portal hypertension may influence gastrointestinal transit.

BACKGROUND: Gastrointestinal transit studies have shown contradictory results in patients with portal hypertension. We have studied gastric emptying. small-bowel transit and colonic transit in patients with portal hypertension. The association between small-bowel bacterial overgrowth and gastrointestinal transit was assessed. METHODS: Sixteen patients (6 females) with portal hypertension and esophageal varices were included. A newly developed radiological procedure was used to measure gastrointestinal transit during one visit. Variceal pressure was measured and culture of small-bowel aspirate was used to diagnose small-bowel bacterial overgrowth. The results were compared to results obtained in 83 healthy subjects. RESULTS: Half gastric emptying time in male patients was 3.8 (0.9-5.8) h versus 2.5 (0.4-4.0) h in healthy males (median and percentile 10-90: P < 0.05). Small-bowel residence time in male patients was 5.9 (2.0-13.7) h versus 3.2 (1.5-6.0) h in healthy males (P < 0.05). Small-bowel residence time in patients with bacterial overgrowth was significantly longer than in patients without bacterial overgrowth. Small-bowel residence time was also significantly longer in male patients with alcoholic cirrhosis as compared to male patients with other causes of portal hypertension. Colonic transit in all patients and gastric emptying and small-bowel transit in female patients were not significantly different from healthy subjects. CONCLUSION: Etiology of liver disease and gender may influence transit in patients with portal hypertension. Small-bowel bacterial overgrowth was associated with delayed small-bowel transit.

Adolescent↗

High-resolution analysis of the duodenal interdigestive phase III in humans.

To study the spatial organization of the propagating pressure waves of duodenal phase III, we performed fasting antroduodenal high-resolution manometry with a 16-channel catheter in 12 healthy subjects. The phase III pressure waves diverged in an anterograde and retrograde direction from the start site of each pressure wave. The pressure waves maintained this configuration as the activity front moved distally in the duodenum. The start site of the pressure waves moved gradually to a point approximately 12 cm (median) distal to the pylorus and remained at this point for about 40% of the phase III time before moving further distally. The length of retrograde pressure wave propagation increased to 6 cm (median) as the pressure wave origin moved aborally to a point 10-14 cm distal to the pylorus, and then decreased when the origin of pressure waves reached the distal end of the duodenum. Bidirectional pressure waves dominated in both retrograde and anterograde activity fronts. Three pressure-wave mechanisms behind the duodenal phase IV were observed. Isolated pyloric pressure waves were absent during late duodenal phase III retroperistalsis. Thus, a number of new features of the duodenal phase III-related motility were observed using high-temporospatial resolution recordings.

Adult↗

Impact of sex and psychological factors on the water loading test in functional dyspepsia.

BACKGROUND: The pathogenesis of upper abdominal symptoms in patients with functional dyspepsia (FD) is still unclear. The water loading test (WLT) is a new method for evaluation of gastric function. Our aim was to determine the impact of sex, age and psychological factors on the results of WLT in FD patients, FD-subgroups and healthy controls (HCs), and to evaluate the safety of the test. METHODS: Fifty-six HCs and 35 consecutive patients with FD drank mineral water (100 ml/min) until intolerable. Serum samples for sodium, potassium and creatinine was taken before and after drinking. Water quantity was registered and symptoms were assessed after maximal water intake and 30 min later using a VAS scale. Participants also completed questionnaires measuring psychological general well-being (PGWB) and gastrointestinal symptoms (GSRS and Mearin score). RESULTS: Healthy men drank more than healthy women, 2350 +/- 105 ml versus 1860 +/- 100 ml (P < 0.01), and the same gender difference was noted in FD patients, 1770 +/- 115 ml versus 1180 +/- 110 ml (P < 0.01). Maximal water intake was significantly higher in HC than in FD patients, both in males (P < 0.001) and females (P < 0.0001). Age had no impact on drinking capacity. FD patients had more symptoms 30 min after maximal water intake than HCs. Serum sodium decreased from 141 +/- 0.3 mmol/l to 138 +/- 0.5 mmol/l. Two of the assessed psychological factors, general health and depressed mood, correlated with water intake in FD patients (Rho = 0.47, P < 0.01 respectively Rho = 0.41, P < 0.05). CONCLUSION: WLT is a useful, simple and safe test for evaluating symptoms in FD patients. Sex, but not age affects the results of the WLT. Furthermore, psychological factors must also be taken into consideration when interpreting the WLT.

Adult↗

Gastric secretion in cystic fibrosis in relation to the migrating motor complex.

BACKGROUND: Patients with cystic fibrosis (CF) have been claimed to have defect intestinal motility and gastric acid secretion. The aim of this work was to study the interdigestive motility and the motility-related secretions in the upper gastrointestinal tract in patients with CF compared to healthy controls. METHODS: Concomitant gastroduodenal manometry combined with intragastric perfusion was performed in 12 healthy volunteers and 10 patients with CF. RESULTS: Eight CF patients showed a normal migrating motor complex. Motility-related gastric secretion of acid and bicarbonate was evaluated in six patients and did not differ from healthy subjects. Gastric net fluid secretion was significantly decreased in the CF patients and bilirubin reflux was significantly increased. The CF patients with pancreatic insufficiency lacked motility-related variations in plasma levels of motilin and pancreatic peptide. CONCLUSIONS: No defect in fasting motility or gastric secretion of acid or bicarbonate could be seen in well-nourished adult CF patients. The main finding was a significantly lower net fluid secretion and higher bilirubin reflux compared to healthy subjects. Indications of a genetic relationship could be seen.

Adult↗

Quality of life in patients with irritable bowel syndrome seen in referral centers versus primary care: the impact of gender and predominant bowel pattern.

BACKGROUND: Quality of life (QOL) is reduced in patients with irritable bowel syndrome (IBS) and little is known about differences in QOL in relation to referral status, gender and predominant bowel pattern in IBS patients. This study aimed to explore these relationships. METHODS: 343 patients with IBS according to the Rome I criteria (251 females, 92 males) completed five different self-administered questionnaires to evaluate QOL. There were 119 patients with diarrhea-predominant IBS (IBS-D), 93 with constipation-predominant IBS (IBS-C) and 131 with alternating constipation and diarrhea (IBS-A). The study group comprised 209 hospital outpatients and 134 primary care patients. The questionnaires were mailed to the patients with an overall response rate of 88%. RESULTS: QOL was reduced in hospital outpatients compared to primary care patients, but only in females. IBS subgroup (IBS-D), physical fatigue and general health independently predicted referral to a gastroenterologist. Females had lower QOL than males. No differences, except in severity of diarrhea and constipation, were observed between IBS subgroups. Perceived fatigue was related to well-being, psychological and gastrointestinal symptoms. Independent predictors for fatigue were depression, trait anxiety, general health and vitality, along with eating dysfunction and female sex. CONCLUSION: IBS female patients seen in referral centers versus primary care is a highly selected group with reduced QOL. QOL in IBS is affected by gender, but not by subgroup. Our findings have implications for the generalizability of results in IBS trials. Fatigue is a common symptom in IBS that correlates to general well-being and psychological and subjective gastrointestinal symptoms.

Adolescent↗

Long-term course in collagenous colitis and the impact of bile acid malabsorption and bile acid sequestrants on histopathology and clinical features.

BACKGROUND: Bile acid malabsorption is common in collagenous colitis, although long-term follow-up data on the impact of bile acids are limited. The aim was to study whether bile acid malabsorption is a permanent finding, with an impact on histopathology and clinical features in collagenous colitis. METHODS: The objective was to reinvestigate 27 patients with collagenous colitis > or = 3 years after index investigation. The clinical course was evaluated by means of an interview, a review of the hospital records and registration of symptoms over a period of 7 days. The patients were invited to undergo a repeat colonoscopy and 75SeHCAT measurement. Initial and follow-up data and 75SeHCAT values from 29 controls were compared. RESULTS: The median follow-up time was 4.2 (range 3-5.3) years. Twenty-two patients underwent a repeat 75SeHCAT test, 23 patients a colonoscopy and in 25 patients the clinical course could be evaluated. The 75SeHCAT values were abnormal in 32% at follow-up versus 44% at index, and the median retention value was 19% (range 2-69) versus 12% (range 0.5-41) (P = 0.024) although lower than in the control groups figure of 38% (range 8-91) (P < 0.005). Histopathology had improved independently of bile acid malabsorption, gender, smoking and autoimmune disease at follow-up. Four were normalized. Patients on bile acid binders had no significant change of histopathology. Four patients had recovered, seven displayed an intermittent course and 14 had continuous diarrhoea. CONCLUSIONS: Collagenous colitis and bile acid malabsorption seem to be associated yet independent disorders. The histopathology improves during the long-term course although only a few patients resolve.

Bile Acids and Salts↗

An exaggerated sensory component of the gastrocolonic response in patients with irritable bowel syndrome.

BACKGROUND/AIMS: Visceral hypersensitivity is a feature of the irritable bowel syndrome (IBS). Postprandial symptoms are common in these patients. The effects of nutrients on colonic perception in IBS are incompletely understood. SUBJECTS: We studied 13 healthy subjects and 16 patients with IBS-eight had diarrhoea predominant (IBS-D) and eight constipation predominant (IBS-C) IBS. METHODS: Colonic perception thresholds to balloon distension and viscerosomatic referral pattern were assessed before and after duodenal infusion of lipid or saline, respectively. At the end of the infusions, plasma levels of gastrointestinal peptides were determined. RESULTS: Lipids lowered the thresholds for first sensation, gas, discomfort, and pain in the IBS group but only for gas in the control group. The percent reduction in thresholds for gas and pain after lipids was greater in the IBS and IBS-D groups but not in the IBS-C group compared with controls. IBS patients had an increased area of referred discomfort and pain after lipids compared with before infusion whereas the referral area remained unchanged in controls. No group differences in colonic tone or compliance were observed. In both groups higher levels of cholecystokinin, pancreatic polypeptide, peptide YY, vasoactive intestinal polypeptide, and neuropeptide Y were seen after lipids. Motilin levels were higher in patients and differences in the subgroups were observed. Levels of corticotrophin releasing factor were lower in the constipated group than in the diarrhoea group. CONCLUSIONS: Postprandial symptoms in IBS patients may be explained in part by a nutrient dependent exaggerated sensory component of the gastrocolonic response.

Adult↗