BACKGROUND/AIMS: To employ an experimental model of opioid-induced bowel dysfunction in healthy human volunteers, and evaluate the impact of opioid treatment compared to placebo on gastrointestinal (GI) symptoms and motility assessed by questionnaires and regional GI transit times using the 3-dimensional (3D)-Transit system. METHODS: Twenty-five healthy males were randomly assigned to oxycodone or placebo for 5 days in a double blind, crossover design. Adverse GI effects were measured with the bowel function index, gastrointestinal symptom rating scale, patient assessment of constipation symptom questionnaire, and Bristol stool form scale. Regional GI transit times were determined using the 3D-Transit system, and segmental transit times in the colon were determined using a custom Matlab® graphical user interface. RESULTS: GI symptom scores increased significantly across all applied GI questionnaires during opioid treatment. Oxycodone increased median total GI transit time from 22.2 to 43.9 hours (P < 0.001), segmental transit times in the cecum and ascending colon from 5.7 to 9.9 hours (P = 0.012), rectosigmoid colon transit from 2.7 to 9.0 hours (P = 0.044), and colorectal transit time from 18.6 to 38.6 hours (P = 0.001). No associations between questionnaire scores and segmental transit times were detected. CONCLUSIONS: Self-assessed GI adverse effects and increased GI transit times in different segments were induced during oxycodone treatment. This detailed information about segmental changes in motility has great potential for future interventional head-to-head trials of different laxative regimes for prevention and treatment of constipation.
Analgesics ; Cecum ; Colon ; Colon, Ascending ; Constipation ; Cross-Over Studies ; Gastrointestinal Transit* ; Healthy Volunteers ; Humans ; Male ; Models, Theoretical ; Oxycodone

BACKGROUND/AIMS: In patients with neuroendocrine tumors, excessive production of serotonin and other amines may cause the carcinoid syndrome, which is mainly characterized by diarrhea and flushing. Little is known about the pathophysiology of carcinoid diarrhea. In several other groups of patients, diarrhea may be associated with rectal hypersensitivity and increased rectal tone. Therefore, the aim of the present study was to compare rectal sensitivity and compliance in patients with carcinoid diarrhea and in healthy subjects. METHODS: Twelve patients (6 males, aged 54-78 years, median 65 years), with carcinoid diarrhea and 19 healthy subjects (7 males, aged 50-78 years, median 61 years) were included. Rectal mechanical and heat stimulation was used for assessment of rectal mechano-sensory properties. RESULTS: Overall, 5.3% higher temperatures were needed to elicit sensory responses in patients with carcinoid diarrhea than in healthy subjects (P = 0.015). Posthoc analyses revealed that the sensory threshold to heat was 48.1 ± 3.1℃ in patients vs 44.7 ± 4.7℃ in healthy subjects (P = 0.041). In contrast, patients and healthy subjects showed no overall differences in rectal sensory response to mechanical distension (P = 0.731) or rectal compliance (P = 0.990). CONCLUSIONS: Patients with carcinoid diarrhea have higher sensory thresholds to heat stimulation in comparison to healthy subjects, but normal rectal sensation to mechanical distension and normal compliance. Therefore, treatment of carcinoid diarrhea should aim at prolonging gastrointestinal transit and decreasing secretion, rather than modifying rectal mechano-sensory function.
Amines ; Carcinoid Tumor* ; Compliance ; Diarrhea* ; Flushing ; Gastrointestinal Transit ; Hot Temperature ; Humans ; Hypersensitivity ; Male ; Neuroendocrine Tumors ; Rectum ; Sensation ; Sensory Thresholds ; Serotonin

BACKGROUND/AIMS: The paucity of knowledge regarding gastrointestinal motility in patients with neuroendocrine tumors and carcinoid diarrhea restricts targeted treatment. 3D-Transit is a novel, minimally invasive, ambulatory method for description of gastrointestinal motility. The system has not yet been evaluated in any group of patients. We aimed to test the performance of 3D-Transit in patients with carcinoid diarrhea and to compare the patients' regional gastrointestinal transit times (GITT) and colonic motility patterns with those of healthy subjects. METHODS: Fifteen healthy volunteers and seven patients with neuroendocrine tumor and at least 3 bowel movements per day were investigated with 3D-Transit and standard radiopaque markers. RESULTS: Total GITT assessed with 3D-Transit and radiopaque markers were well correlated (Spearman's rho = 0.64, P = 0.002). Median total GITT was 12.5 (range: 8.5-47.2) hours in patients versus 25.1 (range: 13.1-142.3) hours in healthy (P = 0.007). There was no difference in gastric emptying (P = 0.778). Median small intestinal transit time was 3.8 (range: 1.4-5.5) hours in patients versus 4.4 (range: 1.8-7.2) hours in healthy subjects (P = 0.044). Median colorectal transit time was 5.2 (range: 2.9-40.1) hours in patients versus 18.1 (range: 5.0-134.0) hours in healthy subjects (P = 0.012). Median frequency of pansegmental colonic movements was 0.45 (range: 0.03-1.02) per hour in patients and 0.07 (range: 0-0.61) per hour in healthy subjects (P = 0.045). CONCLUSIONS: Three-dimensional Transit allows assessment of regional GITT in patients with diarrhea. Patients with carcinoid diarrhea have faster than normal gastrointestinal transit due to faster small intestinal and colorectal transit times. The latter is caused by an increased frequency of pansegmental colonic movements.
Capsules ; Carcinoid Tumor* ; Colon ; Diarrhea* ; Gastric Emptying ; Gastrointestinal Motility ; Gastrointestinal Transit* ; Healthy Volunteers ; Humans ; Neuroendocrine Tumors

BACKGROUND/AIMS: Recurrent nausea and/or vomiting are common complications of diabetes mellitus. The conditions severely impact the quality of life of patients and often cause repeated admissions to hospital incurring significant healthcare costs. If standard treatment fails, gastric electrical stimulation (GES) may be offered in selected cases, as a minimally invasive, but expensive, therapeutic option. Our aims are to evaluate the clinical effect and the cost-utility of GES as a treatment for severe diabetic recurrent nausea and/or vomiting. METHODS: Among 33 diabetes patients implanted with GES because of recurrent nausea and/or vomiting, 30 were available for evaluation. The effect of treatment was assessed prospectively using symptom-diaries and the SF-36 questionnaires at baseline, after 6 and 12 months, and thereafter yearly. The number of days in hospital due to symptoms related to gastrointestinal dysfunction was calculated using hospital records 12 months prior to and 12 months after implantation. RESULTS: The surgical procedures were performed without mortality or major complications. Six months after surgery 78% of the respondents had at least 50% reduction in time with nausea and 48% had at least 50% reduction in days with vomiting. Symptom relief persisted at follow-up after at least 4 years. Quality adjusted life years improved after GES, which was cost-effective after 24 months. CONCLUSIONS: GES reduces symptoms and improves quality of life in diabetes patients with recurrent nausea and/or vomiting. The procedure is supposed as cost-effective over a 2-year time horizon.
Diabetes Complications ; Diabetes Mellitus ; Electric Stimulation* ; Follow-Up Studies ; Health Care Costs ; Hospital Records ; Humans ; Mortality ; Nausea* ; Prospective Studies ; Quality of Life ; Quality-Adjusted Life Years ; Surveys and Questionnaires ; Vomiting*

BACKGROUND/AIMS: Opioid-induced constipation (OIC) is the most common gastrointestinal (GI) side effect to opioid treatment. Opioid receptor antagonists against OIC have been introduced, but their efficacy has not been directly compared to conventional laxatives. Our aim was to compare symptoms and objective parameters of gut function in an experimental model of OIC during treatment with the opioid antagonist naloxone and oxycodone in prolonged-release (PR) formulation versus oxycodone plus macrogol 3350. METHODS: In this randomized, double-blind, crossover trial 20 healthy men received a 5-day treatment of combined PR oxycodone/naloxone or PR oxycodone plus macrogol 3350. Regional GI transit times and segmental colorectal transit were assessed with the Motilis 3D-Transit electromagnetic capsule system. Colorectal volumes were determined by MRI. OIC symptoms were assessed with validated questionnaires, along with stool frequency and consistency. RESULTS: Total colorectal volume did not change after 5 days’ treatment with PR oxycodone/naloxone (941 vs 1036 mL; P = 0.091), but increased significantly after PR oxycodone plus macrogol treatment (912 vs 1123 mL; P < 0.001). Neither regional GI transit times nor segmental colorectal transit differed between the treatments (all P > 0.05). The Patient Assessment of Constipation Symptom Questionnaire abdominal symptoms score was lower during PR oxycodone/naloxone compared to PR oxycodone plus macrogol (0.2 vs 3.2; P = 0.002). Stool frequency was lower during PR oxycodone/naloxone compared to PR oxycodone plus macrogol (4.2 vs 5.4; P = 0.035). CONCLUSIONS: PR oxycodone plus macrogol increases colorectal volume, but does not improve GI transit compared to PR oxycodone/naloxone. However, PR oxycodone/naloxone results in a lower abdominal symptom burden, despite higher stool frequency during macrogol treatment.
Analgesics, Opioid ; Constipation ; Humans ; Laxatives ; Magnetic Resonance Imaging ; Magnets ; Male ; Models, Theoretical ; Naloxone ; Narcotic Antagonists ; Oxycodone ; Polyethylene Glycols

BACKGROUND/AIMS: Efficient transport through the esophago-gastric junction (EGJ) requires synchronized circular and longitudinal muscle contraction of the esophagus including relaxation of the lower esophageal sphincter (LES). However, there is a scarcity of technology for measuring esophagus movements in the longitudinal (axial) direction. The aim of this study is to develop new analytical tools for dynamic evaluation of the length change and axial movement of the human LES based on the functional luminal imaging probe (FLIP) technology and to present normal signatures for the selected parameters. METHODS: Six healthy volunteers without hiatal hernia were included. Data were analyzed from stepwise LES distensions at 20, 30, and 40 mL bag volumes. The bag pressure and the diameter change were used for motion analysis in the LES. The cyclic bag pressure frequency was used to distinguish dynamic changes of the LES induced by respiration and secondary peristalsis. RESULTS: Cyclic fluctuations of the LES were evoked by respiration and isovolumetric distension, with phasic changes of bag pressure, diameter, length, and axial movement of the LES narrow zone. Compared to the respiration-induced LES fluctuations, peristaltic contractions increased the contraction pressure amplitude (P < 0.001), shortening (P < 0.001), axial movement (P < 0.001), and diameter change (P < 0.01) of the narrow zone. The length of the narrow zone shortened as function of the pressure increase. CONCLUSIONS: FLIP can be used for evaluation of dynamic length changes and axial movement of the human LES. The method may shed light on abnormal longitudinal muscle activity in esophageal disorders.
Esophageal Sphincter, Lower ; Esophagus ; Healthy Volunteers ; Hernia, Hiatal ; Humans ; Methods ; Muscle Contraction ; Peristalsis ; Phenobarbital ; Relaxation ; Respiration

BACKGROUND/AIMS: Opioids cause gastrointestinal (GI) dysmotility, decrease gut secretion, and affect gut sphincters. Symptoms of opioid-induced bowel dysfunction may be alleviated by peripherally acting opioid antagonists like naloxegol, but detailed knowledge on GI effects of this drug is lacking. We hypothesized that naloxegol, compared to placebo, would reduce GI transit time and colonic fecal volume in opioid-treated healthy participants. METHODS: We conducted a randomized, double-blinded, single-center, 2-way cross-over study in 24 healthy males, randomized to a 6 day treatment period of oxycodone (15 mg twice a day) co-administered with either naloxegol (25 mg once a day) or matching placebo. Participants swallowed an electromagnetic capsule which determined GI transit times. Colonic fecal volume was quantified with magnetic resonance imaging both pre-treatment and post-treatment. RESULTS: Naloxegol reduced total GI transit time by 21% (56 hours vs 71 hours, P = 0.02) and colonic transit time by 23% (45 hours vs 59 hours, P < 0.01), compared to placebo. However, no difference in colonic fecal volume was found (818 mL vs 884 mL, P = 0.20). CONCLUSIONS: Short-term administration of naloxegol in healthy participants reverses the retardation of total GI and colonic transit induced by oxycodone. This supports the use of naloxegol in the treatment of GI side effects to opioid treatment, and add knowledge to the current understanding of mechanisms behind peripherally-acting opioid antagonists.
Analgesics, Opioid ; Colon ; Constipation ; Cross-Over Studies ; Gastrointestinal Transit ; Healthy Volunteers ; Humans ; Magnetic Resonance Imaging ; Magnets ; Male ; Narcotic Antagonists ; Oxycodone

Background/Aims: Patients with diabetes mellitus (DM) often suffer from gastrointestinal (GI) symptoms, but these correlate poorly to established objective GI motility measures. Our aim is to perform a detailed evaluation of potential measures of gastric and small intestinal motility in patients with DM type 1 and severe GI symptoms. Methods: Twenty patients with DM and 20 healthy controls (HCs) were included. GI motility was examined with a 3-dimensional-Transit capsule, while organ volumes were determined by CT scans. Results: Patients with DM and HCs did not differ with regard to median gastric contraction frequency (DM: 3.0 contractions/minute [interquartile range {IQR}, 2.9-3.0]; HCs: 2.9 [IQR, 2.8-3.1]; P= 0.725), amplitude of gastric contractions (DM: 9 mm [IQR, 8-11]; HCs: 11 mm (IQR, 9-12); P = 0.151) or fasting volume of the stomach wall (DM: 149 cm3 [IQR, 112-187]; HCs: 132 cm3 [IQR, 107-154]; P= 0.121). Median gastric emptying time was prolonged in patients (DM: 3.3 hours [IQR, 2.6-4.6]; HCs: 2.4 hours [IQR, 1.8-2.7];P= 0.002). No difference was found in small intestinal transit time (DM: 5 hours [IQR, 3.7-5.6]; HCs: 4.8 hours [IQR, 3.9-6.0]; P = 0.883). However, patients with DM had significantly larger volume of the small intestinal wall (DM: 623 cm3 [IQR, 487-766]; HCs: 478 cm 3 [IQR, 393-589]; P = 0.003). Among patients, 13 (68%) had small intestinal wall volume and 9 (50%) had gastric emptying time above the upper 95% percentile of HCs. Conclusion In our study, gastric emptying time and volume of the small intestinal wall appeared to be the best objective measures in patients with DM type 1 and symptoms and gastroenteropathy.

Background/Aims: Patients with diabetes mellitus (DM) often suffer from gastrointestinal (GI) symptoms, but these correlate poorly to established objective GI motility measures. Our aim is to perform a detailed evaluation of potential measures of gastric and small intestinal motility in patients with DM type 1 and severe GI symptoms. Methods: Twenty patients with DM and 20 healthy controls (HCs) were included. GI motility was examined with a 3-dimensional-Transit capsule, while organ volumes were determined by CT scans. Results: Patients with DM and HCs did not differ with regard to median gastric contraction frequency (DM: 3.0 contractions/minute [interquartile range {IQR}, 2.9-3.0]; HCs: 2.9 [IQR, 2.8-3.1]; P= 0.725), amplitude of gastric contractions (DM: 9 mm [IQR, 8-11]; HCs: 11 mm (IQR, 9-12); P = 0.151) or fasting volume of the stomach wall (DM: 149 cm3 [IQR, 112-187]; HCs: 132 cm3 [IQR, 107-154]; P= 0.121). Median gastric emptying time was prolonged in patients (DM: 3.3 hours [IQR, 2.6-4.6]; HCs: 2.4 hours [IQR, 1.8-2.7];P= 0.002). No difference was found in small intestinal transit time (DM: 5 hours [IQR, 3.7-5.6]; HCs: 4.8 hours [IQR, 3.9-6.0]; P = 0.883). However, patients with DM had significantly larger volume of the small intestinal wall (DM: 623 cm3 [IQR, 487-766]; HCs: 478 cm 3 [IQR, 393-589]; P = 0.003). Among patients, 13 (68%) had small intestinal wall volume and 9 (50%) had gastric emptying time above the upper 95% percentile of HCs. Conclusion In our study, gastric emptying time and volume of the small intestinal wall appeared to be the best objective measures in patients with DM type 1 and symptoms and gastroenteropathy.