Gastric emptying characteristics of a novel (13)C-octanoate-labeled muffin meal

GOALS: Determine the gastric emptying characteristics of a novel, 350-kcal test meal consisting of two muffins, using scintigraphy and the 13C-octanoate breath test (OBT). STUDY: Healthy volunteers underwent three studies on separate days within a 1-week period. On day 1, we measured emptying of the 350-kcal muffin test meal labeled simultaneously with 99mTc sulfur colloid and 13C-octanoate. On day 2, reproducibility of the OBT using a single-labeled 350-kcal test meal was assessed. On day 3, the effect of erythromycin on the 350-kcal OBT was determined. RESULTS: The mean (+/-SD) half-emptying time (T1/2) as measured by scintigraphy was 104 +/- 24 minutes, versus 212 +/- 52 minutes by OBT. There was a strong correlation between T1/2 determined by scintigraphy and the breath test (r = 0.83). Multiple linear regression analysis identified a significant relationship between T1/2 determined by scintigraphy and the 90-and 180-minute breath samples. There was a strong correlation (r = 0.830, slope = 0.732 +/- 0.120 [SE], intercept = 26.4 +/- 12.7) between the T1/2 obtained using the regression equation and the actual T1/2 obtained by scintigraphy. The mean T1/2 (+/-SD) for replicate determinations using the OBT was 209 +/- 52 minutes, compared with 196 +/- 42 minutes on days 1 and 2, respectively (not significant, p = 0.28, paired Student t test). Treatment with erythromycin on day 3 produced a significant decrease in T1/2 (155 +/- 49 minutes, p = 0.002). CONCLUSIONS: The 350-kcal muffin meal OBT provides a convenient, nonscintigraphic way of measuring solid-phase gastric emptying. Multiple linear regression appears promising as a method of analyzing OBT data and may allow for an abbreviated breath test protocol.     

Simultaneous measurement of gastric emptying of a solid meal by ultrasound and by scintigraphy

OBJECTIVE: Although ultrasonic imaging may represent a valid alternative to scintigraphy for measurement of gastric emptying, most studies comparing the two methods have been carried out with liquid meals. The aim of this study was to compare scintigraphic and ultrasonographic measurements of gastric emptying of a solid meal in healthy subjects and in patients with possible delay in emptying. METHODS: Nineteen subjects were studied: five controls, six patients with gastroesophageal reflux, and eight patients with dysmotility-like dyspepsia. Gastric emptying was measured by both scintigraphy and ultrasonography after ingestion of an 800-calorie solid, realistic meal containing 99mTc-labeled chicken liver. Scintigraphic measurements were made every 15 min for 6 h, and ultrasonic imaging of antral sections was undertaken every 15 min for the first 1 h and every 30 min thereafter. Total emptying times were calculated independently using the two methods, and the emptying patterns recorded by the two methods were compared. RESULTS: Maximal antral dilation occurred 30 min (range 0-90 min) after the end of the meal and persisted until 96 +/- 42 min, by which time gastric radioactivity had decreased from its maximum by 43% +/- 23%. From this time on, the antral cross-sectional area returned toward the basal value, declining faster than the gastric counts recorded by scintigraphy. Total emptying times measured by ultrasound and by scintigraphy were in good agreement in all subjects, with a mean difference of only 4.5 min (limits of agreement, -17.1 to 21.6 min). CONCLUSIONS: Ultrasonographic measurement of antral cross-sectional area provides a valid alternative to scintigraphy for the measurement of total gastric emptying of a solid meal. It is less reliable if other parameters of gastric emptying such as T(1/2) are required.     

Radioisotopic assessment of gastric emptying of solids in elderly subjects

BACKGROUND AND AIMS: Few studies in literature have investigated the gastric emptying of solids in elderly subjects. We assessed the differences between young and elderly subjects in the gastric emptying rate of solids by a radioisotopic method. METHODS: Two groups of 15 elderly male subjects (mean age 68.20 years and 77.26 years, respectively) and a group of young male subjects (mean age 30.23 years) underwent a radioisotopic study of gastric emptying after eating a radiolabeled solid meal. Half-time of gastric emptying (T1/2) and emptying index (EI), i.e. rate of gastric emptying at 120 min, were measured with two opposing detectors connected to a computerized rate-meter. Results are expressed as means +/- SD. RESULTS: Significantly different values were obtained in the two groups both at T1/2 (183+/-88 and 195+/-75, respectively) and EI (0.40+/-0.3 and 0.36+/-0.4), compared with young subjects (T1/2=53+/-23; EI=1.10+/-0.3) (p<0.0001). CONCLUSIONS: Gastric emptying of solids is significantly delayed in elderly men; this variable must be taken into account when studies on gastric emptying rates are performed.     

Infrared spectrometry based 13C-octanoic acid breath test in measuring human solid gastric emptying

BACKGROUND AND AIMS: Because of the convenience of non-dispersive infrared spectrometry (NDIRS), we attempted to validate the usefulness of NDIRS compared with scintigraphy in human solid gastric emptying (GE) measurement, and tried to establish the normal range of solid GE based on NDIRS. METHODS: Twelve healthy volunteers (three men, nine women) were recruited for simultaneous scintigraphy and 13C-octanoic acid breath test (13C-OABT) studies. Stomach half-emptying time (t1/2) and lag phase (tlag) were the two main GE parameters measured and correlated. The breath samples were analyzed using NDIRS every 10-15 min for a total of 6 h, while scintigraphy was taken minute by minute for the first 30 min, then hourly for 4 h. Another 32 healthy volunteers (19 men, 13 women) received only the 13C-OABT to measure their solid GE. RESULTS: A significant correlation for t1/2 was found between the breath test and scintigraphy (r = 0.85, P = 0.001), while tlag was also positively correlated (r = 0.73, P = 0.007). The reference range of t1/2B based on all 44 subjects was 89.4-185.1 min (135.9 +/- 21.1 min (mean +/- SD)), while the range for tlagB was 37.1-117.8 min (81.9 +/- 17.4 min). No demographic characteristics were found to influence the GE parameters. CONCLUSIONS: 13C-octanoic acid breath test determined by NDIRS is a simple, non-invasive and reliable measurement, which may provide an 'office-based' tool to detect solid GE.     

The measurement of gastric emptying time with 3-D ultrasonography]

BACKGROUND/AIMS: Three dimensional (3-D) ultrasonography is definitely more accurate than conventional 2-D ultrasonography in volume measurement of intra-abdominal organs. However, its application in measuring gastric emptying time has been limited. Thus, we tried to measure gastric antral emptying time by using 3-D ultrasonography and compare with that by radio-scintigraphy. METHODS: We performed both 3-D ultrasonography and radio-scintigraphy on the same day in 23 healthy subjects. After overnight fast, the subjects ingested 500 mL of soup meal (84 Kcal) that had been pre-mixed with 1 mCi of technetium(99m). The half emptying time (T(1/2)) measured by 3-D ultrasonography was defined by the time when the gastric antral volume decreased to half. RESULTS: The mean T(1/2) of 23 healthy subjects measured by 3-D ultrasonography was 23.4 +/- 10.5 min, while that measured by scintigraphy was 28.4 +/- 14.4 min. The difference (p=0.11 by paired t-test) between the two methods was not significant. Moreover, no significant correlation of T1/2 between the two methods (r=0.361, p=0.09) was observed. CONCLUSIONS: Measuring gastric antral emptying time with 3-D ultrasonography may be useful but require further validation studies and advance in technology.     

Exercise increases solid meal gastric emptying rates in men

Gastric emptying rates of radiolabeled beef stew meals were measured in 10 healthy, young (median age = 27 years) male subjects on each of three randomly chosen study days. The subjects either (1) stood at rest, (2) walked on an exercise treadmill at 3.2 km/hr, or (3) at 6.4 km/hr during the study while gastric emptying was being monitored by externally positioned gamma cameras. Compared to the standing at rest study, exercise significantly increased gastric emptying (at rest emptying half-time (t1/2) = 72.6 +/- 7.6 (SEM) min; 3.2 km/hr t1/2 = 44.5 +/- 3.9 min, P = 0.0051; 6.4 km/hr t1/2 = 32.9 +/- 1.9 min, P = 0.0051). The 6.4 km/hr emptying time was significantly (P = 0.0249) faster than the 3.2 km/hr emptying time. Thus, the amount of exercise is a physiological factor that alters solid meal gastric emptying rates.     

Validation of an ultrasonographic method of gastric emptying measurement in men

Our purpose was to validate an ultrasonographic technique based on the assessment of the gastric antrum. Sixteen patients presenting with various functional disorders were studied by ultrasound on two occasions. Ten healthy volunteers were simultaneously studied by scinti- and ultrasonic scans. After an overnight fast, the healthy subjects ingested a 2,000 kJ test meal containing 150 microCi of 111In DTPA in 250 ml orange juice and 3 mCi of 99m Tc sulfur colloid in chicken liver. Using an ultrasound scanner fitted with a 3.5 MHz transducer, the area of the gastric antrum section was always measured in the same plane. Ultrasonographic measurement of gastric emptying rate was feasible in all of the 10 healthy subjects and in 14 of 16 selected patients. The ultrasonographic method was reproducible, and repeated t 1/2 measurements in 14 patients correlated well (95.3 +/- 27.9 vs 99.2 +/- 20.6 min; r = 0.70, P less than 0.001). The t 1/2 measurement was 39.4 +/- 7.7 min with the ultrasonographic method, and correlated well with 36.4 +/- 4.3 min for the t 1/2 measurement of the liquid phase with the scintigraphic method. We conclude that the ultrasonic method was reproducible and could be used for assessment of gastric emptying rate when repeated measurements are necessary, especially in pharmacologic studies.     

A longitudinal study of gastric emptying and upper gastrointestinal symptoms in patients with diabetes mellitus

PURPOSE: To evaluate the natural history of gastric emptying and upper gastrointestinal symptoms in patients with diabetes mellitus. SUBJECTS AND METHODS: We enrolled 20 patients (6 men, 14 women) with diabetes mellitus (16 with type 1 diabetes, 4 with type 2 diabetes). Each had measurements of gastric emptying of a solid (100 g of ground beef) and liquid (150 mL of 10% dextrose) meal using scintigraphy, glycemic control (glycosylated hemoglobin [HbA(1c)] and mean blood glucose levels), upper gastrointestinal symptoms, and autonomic nerve function at baseline and after a mean (+/- SD) of 12.3 +/- 3.1 years of follow-up. RESULTS: There were no differences in mean gastric emptying of the solid component (retention at 100 minutes at baseline: 56% +/- 19% vs. follow-up: 51% +/- 21%, P = 0.23) or the liquid component (time for 50% to empty at baseline: 33 +/- 11 minutes vs. follow-up: 31 +/- 12 minutes, P = 0.71) during follow-up. Mean blood glucose (17.0 +/- 5.6 mmol/L vs. 13.8 +/- 4.9 mmol/L, P = 0.007) and HbA(1c) (8.4% +/- 2.3% vs. 7.6% +/- 1.3%, P = 0.03) levels were lower at follow-up. There was no difference in symptom score (baseline: 3.9 +/- 2.7 vs. follow-up: 4.2 +/- 4.0, P = 0.78). There was evidence of autonomic neuropathy in 7 patients (35%) at baseline and 16 (80%) at follow-up. CONCLUSION: In patients with diabetes mellitus, we did not observe any marked changes in either gastric emptying or upper gastrointestinal symptoms during a 12-year period.     

Glucose control is not improved by accelerating gastric emptying in patients with type 1 diabetes mellitus and gastroparesis. a pilot study with cisapride as a model drug.

The present pilot study investigated whether acceleration of gastric emptying in patients with type 1 diabetes and delayed gastric emptying (a possible cause of poorly controlled diabetes) improves long-term glucose control. Eight outpatients with diabetes (age 28-63 years, mean diabetes duration 24.6+/-6.0 years) and delayed gastric emptying of radio-opaque markers were randomised and treated, for three months each, with a prokinetic drug (cisapride 20 mg twice daily) and placebo. Mean capillary glucose, glucose variability (M-values, MAGE), fructosamine, and HbA1c were assessed. Gastric emptying of a solid standard meal was measured by scintigraphy after each treatment period. Chronic administration of a prokinetic drug resulted in improved solid gastric emptying (percentage residual) at 120 min (p=0.025). The percentage residual was 43.6+/-9.6 % during prokinetic treatment and 59.7+/-9.9 % during placebo (standard error of paired differences 5.7 %). The mean gastric emptying time (t/2) of solids was 88 min during prokinetic treatment compared to 113 min in the placebo arm (SE of paired differences 14 min; p=0.09). Mean blood glucose values (9.0+/-3.8 vs. 8.8+/-3.7 mmol/l), daily glucose variability (MAGE 6.8+/-1.3 vs. 6.3+/-1.6 mmol/l; M-value 15.2+/-2.5 vs. 13.9+/-4.5), and HbA1c at 3 months (7.8+/-1.1 % vs. 7.6+/-1.0 %) were not statistically different between prokinetic drug and placebo treatment. Similarly, the frequency of hypoglycaemic episodes (< or = 3 mmol/l) was not different in both groups (78 vs. 68). Our pilot study showed that long-term acceleration of gastric emptying had no effect on overall glycaemic control, the magnitude of glucose excursions, and hypoglycaemic episodes in patients with diabetic gastroparesis. We do not recommend, therefore, acceleration of gastric emptying as treatment strategy for "brittle diabetes" in patients with type 1 diabetes.     

Measurement of gastric emptying time by real-time ultrasonography

This paper describes an ultrasound method of assessing gastric emptying time based on measurements of the gastric antrum, which is visible in almost all subjects before and after meals. A total of 54 subjects were examined including 18 normal subjects and 36 subjects with idiopathic functional dyspepsia. The emptying time was determined in all subjects by measuring the changes in the cross-sectional area of the gastric antrum. In a subgroup of 34 subjects the volume of the whole antropyloric region was also considered. Measurements were taken by the same observer after fasting and at regular 30-min intervals after a standard 800-cal meal. Final emptying time (calculated in relation to the start of the meal) was considered to be the time at which the antral area or volume returned to basal value. Final emptying time (mean +/- SD) was 248 +/- 39 min in normal subjects and 359 +/- 64 min in patients with functional dyspepsia (p less than 0.001). A significantly higher degree of dilatation of the gastric antrum was found in dyspeptic patients than in control subjects. Barium x-ray of the stomach in 19 subjects always confirmed the ultrasound finding on the presence or absence of contents within the stomach. We conclude that this kind of ultrasound study of the antropyloric region allows accurate determination of total gastric emptying time.     

Effect of ageing on the gastro-intestinal transit of a lactulose-supplemented mixed solid-liquid meal in humans

Gastro-intestinal transit of a mixed solid-liquid meal containing wheat bread, scrambled eggs, coffee labelled with 99mTc, orange juice with lactulose and indigocarmine was evaluated in 21 young control (mean age 33.5 years) and 25 elderly subjects (mean age 81.7 years) without gastrointestinal complaints or severe medical illness. The rate of gastric emptying was determined by an anterior gamma camera technique, mouth-to-caecum transit by the hydrogen breath test and whole-gut transit by the first stool passage of indigocarmine. Gastric emptying was significantly prolonged in older subjects: t1/2 = 136 +/- (SEM) 13 versus 81 +/- 4 min; p less than 0.001. Concerning mouth-to-caecum or whole-gut transit time, significant differences between the two study groups were not detected.     

Metoclopramide-Induced Normalization of Impaired Gastric Emptying in Spinal Cord Injury

In a partial, two-way crossover study of gastric emptying (GE) in spinal cord injury (SCI), fasted, healthy, unmedicated male volunteers were given a 99mTc-labeled liquid meal on two occasions. Metoclopramide (10 mg) was administered intravenously to each subject before the second evaluation of GE. We used single and multiexponential models with linear and nonlinear least-squares regression techniques to study the time-course of the disappearance of 99mTc from the stomach. The GE pattern in all subjects was most accurately characterized by nonlinear analysis (NONLIN) and consisted of two components, an initial adynamic phase and a phase of rapid emptying. The GE t1/2 of a liquid meal decreased from 106.6 +/- 58.3 min (mean +/- SD) in all SCI subjects (quadriplegic plus paraplegic) prior to treatment to 21.6 +/- 8.2 min after the intravenous administration of metoclopramide (p less than 0.006). Significant correlations between GE t1/2 and injury duration (yr) or level of spinal injury were observed. Impaired gastric emptying in SCI can be pharmacologically modified by metoclopramide to resemble a normal gastric emptying profile. Metoclopramide-altered gastric emptying in SCI may be expected to result in changes in the therapeutic efficacy of orally administered drugs when drug absorption is dependent on gastric motility or emptying efficiency.     

Scintigraphic study of gastric emptying and intragastric distribution of a solid meal: gender differences

Gender-related differences in gastric emptying are still controversial. The aims of this study were: to confirm the sex-related difference in gastric emptying of a solid meal and to investigate its association with different patterns of meal distribution between the proximal and distal gastric compartments. Eighteen healthy volunteers (nine males, mean age 35 +/- 9 years; nine females, mean age: 41 +/- 11 years) were studied in the morning, after ingestion of the solid test-meal (an omelette labeled with 185MBq of 99mTc-sulfur colloid). Simultaneous anterior and posterior images of the stomach were acquired immediately after ingestion of the meal and every 10 minutes for 120 minutes. Time versus activity curves were obtained for the whole, proximal and distal stomach. Gastric T1/2 was longer in women (96.1 +/- 17.2 min) than in men (79.9 +/- 17.8 min; P = 0.02). The analysis of the meal distribution inside the stomach showed no differences between males and females in proximal gastric emptying, but the meal retention in the distal compartment was significantly increased among women (P = 0.04). In conclusion, gastric emptying of a solid meal is slower in pre-menopausal women than in age-matched men, probably due to an increased retention of the meal in the distal compartment. This should be taken into consideration to avoid misleading diagnosis of gastroparesis for female patients.     

A valid, accurate, office based non-radioactive test for gastric emptying of solids

BACKGROUND: Current breath tests for measurement of gastric emptying of solids are expensive, possibly inaccurate, and require cumbersome calculations. AIMS: We wished to validate a simplified solid gastric emptying test using a [(13)C]Spirulina platensis breath test for accurate results relative to scintigraphy. SUBJECTS: Thirty healthy volunteers. METHODS: We measured gastric emptying of egg containing [(13)C]S platensis and (99m)Tc sulphur colloid by breath (13)CO(2) and scintigraphy over six hours. A generalised linear regression model was used to predict t(1/2) and t(LAG) by scintigraphy from breath (13)CO(2) data. The model was cross validated and normative data calculated for a prepacked [(13)C]meal. RESULTS: Regression models using all breath data over six hours, for the first three hours, and for samples at 75, 90, and 180 minutes ("reduced model") predicted t(1/2) and t(LAG) values similar to scintigraphy (t(LAG) 43 (SD 12) min; t(1/2) 100 (20) min). Standard deviations of differences in t(1/2) and t(LAG) between scintigraphy and the "reduced model" were both 10 minutes. Gastric t(1/2) for the prepacked [(13)C]meal was 91 (15) min (10-90% range: 74-118). CONCLUSION: The [(13)C]S platensis breath test and a simple formula using breath (13)CO(2) at baseline, 90, and 180 minutes measured gastric emptying t(1/2) for solids with results that were comparable with scintigraphy.     

Gastric emptying time of fluids and solids in healthy subjects determined by 13C breath tests: influence of age, sex and body mass index

BACKGROUND AND AIM: Disturbance of gastric emptying leads to a variety of symptoms. Furthermore, gastric motility disorders might play a role in the pathophysiology of functional dyspepsia. In previous studies 13C breath tests were validated as non-invasive tools in the measurement of gastric emptying time. So far, reliable reference values of healthy subjects are missing and the impact of constitutional traits (age, sex, body mass index [BMI]) needs to be clarified. METHODS: A study was conducted in 90 healthy individuals (45 men, 45 women) that assessed the correlation of parameters of gastric emptying (half gastric emptying time [T1/2] and time of fastest gastric emptying [T(lag)]) with age, sex and BMI for fluid and solid test meals by 13C breath tests. 100 mg of sodium acetate or sodium octanoate, respectively, were used as tracers. Breath probes were analyzed by non-dispersive infrared spectroscopy. RESULTS: The mean +/- SD of half gastric emptying time (T1/2) of a fluid test meal was determined to be 80.5 +/- 22.1 min and for T(lag) to be 40.3 +/- 10.2 min. However, the T1/2 and T(lag) of solid meals did not fit to normal distribution and thus median and percentiles were determined. The median time of T1/2 for solids was 127 min (25-75% percentiles: 112.0-168.3 min) and 81.5 min for T(lag) (25-75% percentiles: 65.5-102.0 min). No significant correlation was found between gastric emptying and age, sex or BMI. CONCLUSION: This is the first study to examine gastric emptying in an adequate number of healthy subjects by 13C breath tests. No significant correlation was found with age, sex and BMI. Although there is considerable standard deviation in gastric emptying time, these results may nevertheless serve as reference values for further studies.     

Diminished Retention of Food in the Proximal Stomach Correlates with Increased Acidic Reflux in Patients with Gastroesophageal Reflux Disease and Dyspeptic Symptoms

This work aimed at evaluating the intragastric distribution of food in patients with GERD and dyspepsia and its relationship to acidic reflux episodes. Gastric emptying and food retention in the proximal stomach were evaluated by scintigraphy in 12 healthy subjects and 19 patients with GERD and dyspepsia after a liquid test meal. Patients also underwent 24-hr esophageal pH monitoring, which included a 2-hr postprandial period following a similar test meal. Total gastric emptying was similar in patients and controls, whereas proximal gastric retention (AUCprox/AUCtot) was significantly decreased in patients (mean +/- SD: 0.48 +/- 0.07 vs. 0.56 +/- 0.06; P = 0.02). Within the GERD-dyspepsia group, a significant negative correlation was found between proximal gastric retention and the number of acidic reflux episodes. We concluded that abnormally decreased retention of gastric contents in the proximal stomach after a liquid meal may contribute to the pathogenesis of acidic reflux episodes in patients with GERD and dyspepsia.     

Measurement of gastric emptying in gastroesophageal reflux-related chronic cough

STUDY OBJECTIVES: Gastroesophageal reflux (GER) is one of the most common causes of chronic cough, but the mechanisms of GER-related cough are not well-understood. We tested the hypothesis that gastric emptying is delayed in patients with GER-related chronic cough. DESIGN: We studied 12 patients (7 women; mean age, 53 years; age range, 37 to 68 years) with GER-related chronic cough and a control group of 27 asymptomatic healthy volunteers (16 women; mean age, 37 years; age range, 18 to 62 years). Gastric emptying scintigraphy was performed, and the time at which 50% of the radiolabeled material had left the stomach (T(1/2)) was calculated. RESULTS: There was no statistically significant difference in T(1/2) values between healthy volunteers and subjects with GER-related cough (99 +/- 26 min vs 86 +/- 20 min, respectively; difference between the means, 13 min [95% confidence interval, -4 to 30 min]; p = 0.13). CONCLUSIONS: Gastric emptying was not delayed in patients with GER-related chronic cough. The measurement of gastric emptying did not therefore provide further insights into the mechanisms of GER-related cough or clinically relevant information that would assist in patient management.     

Insulin-induced hypoglycemia accelerates gastric emptying of solids and liquids in long-standing type 1 diabetes

CONTEXT: The rate of gastric emptying of carbohydrate is a major determinant of postprandial glycemia. In healthy subjects and patients with uncomplicated type 1 diabetes, there is evidence that gastric emptying may be accelerated by insulin-induced hypoglycemia. OBJECTIVE: The objective was to determine the effects of acute hypoglycemia on gastric emptying in long-standing type 1 diabetes and evaluate whether the response to hypoglycemia is influenced by the rate of gastric emptying during euglycemia and/or autonomic dysfunction. DESIGN: Gastric emptying of a solid/liquid meal (100 g (99m)Tc-minced beef and 150 ml 67Ga-EDTA-labeled water) was measured by scintigraphy on 2 separate days, during hypoglycemia and euglycemia. SETTING: These studies took place at the Department of Nuclear Medicine, Positron Emission Tomography, and Bone Densitometry at the Royal Adelaide Hospital. PATIENTS: Twenty type 1 patients (4 female, 16 male; age, 45.9 +/- 2.3 yr; duration of known diabetes, 18.0 +/- 2.7 yr) were recruited from outpatient clinics and the Diabetes Centre at the Royal Adelaide Hospital. INTERVENTION: Hypoglycemia (approximately 2.6 mmol/liter) was established 15 min before and maintained for 45 min after meal consumption. On one of the days, autonomic nerve function was evaluated using cardiovascular reflex tests. MAIN OUTCOME MEASURE: The main outcome measure was gastric emptying during hypoglycemia when compared with euglycemia. RESULTS: Twelve of the 20 subjects had autonomic neuropathy. Gastric emptying of both solid (P < 0.001) and liquid (P < 0.05) was faster during hypoglycemia. The magnitude of this acceleration was greater when the rate of gastric emptying during euglycemia was slower (solid, percentage retention at 100 min, r = -0.52, P < 0.05; liquid, 50% emptying time, r = -0.82, P < 0.0001, but not influenced by autonomic nerve function). CONCLUSIONS: Insulin-induced hypoglycemia accelerates gastric emptying of solids and liquids in long-standing type 1 diabetes, even in those patients with delayed emptying, and is likely to be an important mechanism in the counter-regulation of hypoglycemia.     

Pectin delays gastric emptying and increases satiety in obese subjects

As pectin delays gastric emptying in normal subjects and satiety may be linked to the rate of gastric emptying, we designed this study to evaluate, in a group of obese subjects, the effect of adding pectin to a meal on gastric emptying, sensation of satiety, and postprandial plasma cholecystokinin and pancreatic polypeptide levels. We studied gastric emptying of solids in 9 adult obese subjects on 2 separate days in a randomized fashion. On day 1, 15 g of pectin was added to the meal, and on day 2 15 g of methylcellulose was added and served as control. Satiety was evaluated by an analogue rating scale. Pectin significantly delayed gastric emptying time [t1/2 = 116 +/- 23 min vs. 71 +/- 17 min observed with methylcellulose (p less than 0.001)]. Pectin also significantly increased subjects' sensation of satiety [98 +/- 7 vs. 74 +/- 17 (p less than 0.001)]. Postprandial release of cholecystokinin and pancreatic polypeptide was not modified by pectin. As pectin induces satiety and delays gastric emptying in obese patients, it may be a useful adjuvant in the treatment of disorders of overeating.     

Gastric motility dysfunction in patients with multiple sclerosis assessed by gastric emptying scintigraphy.

BACKGROUND: Gastrointestinal tract symptoms are common in patients with multiple sclerosis (MS), especially constipation and/or fecal incontinence. AIMS: To assess gastric emptying in patients with MS to detect the severity of autonomic disturbances in the gastrointestinal tract, and to find the relationship between lower bowel disturbances and the rate of gastric emptying. METHODS: Forty-nine patients with definite MS and 20 control subjects were included in the study. All patients underwent full neurological examination and magnetic resonance imaging of the brain and spinal cord. The labelled meal for gastric emptying scintigraphy consisted of cooked eggs mixed with 3 mCi of technetium-99m colloid, and was followed by serial images at 15 min intervals for 2 h. RESULTS: Five studies were excluded due to technical artifacts. Twenty-one patients (47.7%) demonstrated slow emptying, 15 (34.1%) demonstrated normal and eight (18.2%) demonstrated fast clearance curves. The mean half-time of gastric emptying in MS patients was 96.6+/-22.4 min and the controls showed a mean half-time of 41.3+/-18.7 min (P<0.05). The half-time was longer in patients with constipation; nevertheless, it showed no significant difference compared with patients without constipation (P=0.197). Moreover, although half-time was shorter in patients with fecal incontinence, there was not a significant difference compared with those without fecal incontinence (P=0.654). CONCLUSIONS: The gastric emptying rate is slow in MS patients. As for lower bowel disturbances, the gastric emptying rate was obviously affected in patients complaining of constipation and fecal incontinence, although statistical significance was not reached.