Timing of postprandial dyspeptic symptoms and transpyloric passage of gastric contents.

BACKGROUND: Patients with functional dyspepsia often experience early satiety and discomfort after a meal. The role of early gastric emptying in symptom generation is not known. Our aim was to relate timing of symptoms and early postprandial emptying in functional dyspepsia. METHODS: Twelve patients with functional dyspepsia were investigated during 3 min of fasting, during 3 min of ingesting 500 ml of a meat soup, and during the first 10 min postprandially by means of duplex sonography. RESULTS: Gastric emptying commenced on average 52 sec after the start of ingestion. Transpyloric movements of gastric contents unrelated to peristalsis (that is, alternating transpyloric emptying and reflux within a common chamber created by the terminal antrum, the pylorus, and the duodenal bulb) appeared before peristaltic-related emptying, which commenced after on average 116 sec. In all patients epigastric, meal-related discomfort was experienced after the commencement of transpyloric emptying, on average after 143 sec. A negative correlation was found between intensity of fullness and duration of presymptomatic transpyloric movements of gastric contents (that is, the duodenal 'tasting' period). CONCLUSIONS: The early occurrence of meal-related symptoms suggests that gastric distension is the main factor in symptom generation. However, the onset of symptoms after the commencement of gastric emptying suggests that intestinal tasting receptors are involved in symptom generation. The inverse relationship between the duration of the tasting period and symptom intensity suggests that the time allowed for duodenal tasting might be too short in patients with FD.

Gastric meal accommodation and symptoms in diabetes. A placebo-controlled study of glyceryl trinitrate.

OBJECTIVE: To study mechanisms behind postprandial symptoms in patients with diabetes mellitus and the effect of nitric oxide (NO) on gastric accommodation and symptoms in these patients. DESIGN: A double-blind, placebo-controlled, randomized trial was designed in 20 patients with type 1 diabetes (10 male and 10 female, aged 35.3 +/- 7.6 years). METHODS: 0.5 mg sublingual glyceryl trinitrate (GTN), a donor of exogenous NO, or placebo was administered 5 min prior to a 500 ml soup meal. Gastric accommodation of the meal was assessed by abdominal ultrasound. Accommodation in proximal stomach was visualized in a sagittal area (Psa) and a frontal diameter (Pfd) and accommodation in distal stomach was visualized in a sagittal area of the antrum (Asa). Symptoms were assessed using visual analogue scales. RESULTS: Psa correlated significantly (r = 0.57, P = 0.015) with perception of fullness 5 min after the meal, whereas Pfd correlated significantly (r = 0.67, P = 0.004) with nausea at 15 and at 25 min after the meal. Asa correlated (r = 0.50, P = 0.05) with pain at 5 min, 10 min (r = 0.50, P = 0.05) and 25 min (r = 0.68, P = 0.007). GTN had no significant effect on Psa or Pfd, but reduced significantly (P = 0.05) Asa (1 3.5 +/- 4.5 cm2 with GTN vs 16.1 +/- 4.3 cm2 with placebo). GTN increased significantly (P = 0.04) the intragastric proximal/distal meal distribution ratio (proximal/distal sagittal area), but had no significant effect on symptom scores. CONCLUSION: In patients with diabetes, a large proximal stomach is associated with perception of fullness and a large antrum is associated with perception of pain after a meal. Sublingual administration of GTN prior to the meal decreases the antral area and improves the intragastric meal distribution, but fails to improve symptoms.

Gastric meal accommodation studied by ultrasound in diabetes. Relation to vagal tone.

BACKGROUND: Disturbed gastric meal accommodation may cause abdominal symptoms in patients with functional dyspepsia and diabetes mellitus who have poor vagal control of gastric motility. In the present study we aimed to explore the relation between gastric meal accommodation and vagal tone in diabetic patients with vagal neuropathy. METHODS: Twenty patients with diabetes (DM) (insulin-dependent type; 10 men and 10 women, aged 35.3 +/- 7.6 years) and 20 healthy controls (HC) (10 men and 10 women; aged 34.7 +/- 10.7 years) were studied. Proximal gastric size was assessed with ultrasound in a sagittal area and a frontal diameter. Distal gastric (antrum) size was assessed in a sagittal area. Vagal tone was assessed non-invasively by recording of respiratory sinus arrhythmia (RSA) in beats per minute. RESULTS: Proximal sagittal area was significantly (P = 0.03) smaller in DM (18.5 +/- 5.5 cm2) than in HC (22.2 +/- 4.6 cm2). Proximal frontal diameter did not differ significantly (P = 0.60) between DM and HC (5.9 +/- 1.1 cm versus 5.7 +/- 0.8 cm). Antral area, too, did not differ significantly (P = 0.59) between DM and HC (14.5 +/- 4.1 cm2 versus 13.6 +/- 5.8 cm2). Proximal/distal meal distribution ratio, defined as proximal sagittal area/distal sagittal area, was significantly (P = 0.05) smaller in DM (6.8 +/- 0.6) than in HC (9.9 +/- 5.5). Vagal tone was significantly (P = 0.03) lower in DM (4.5 +/- 1.9 beats/min) than in HC (6.3 +/- 2.7 beats/min). Vagal tone tended (r = 0.33, P = 0.06) to correlate with proximal sagittal area in DM and HC pooled. Vagal tone correlated (r = 0.34, P = 0.05) with proximal frontal diameter in DM and HC pooled. A significant negative correlation (r = -0.39, P = 0.03) was observed between vagal tone and antral area in DM and HC pooled. CONCLUSIONS: Patients with diabetes and low vagal tone have an impaired postprandial gastric meal distribution characterized by a small proximal stomach and a small proximal/distal meal distribution ratio.

Lower postprandial gastric volume response in diabetic patients with vagal neuropathy.

UNLABELLED: Poor relaxation in the stomach after a meal may contribute to disturbed gastric emptying and abdominal discomfort in patients with diabetes mellitus. In this study we aimed to compare barostat-recorded postprandial volume responses in these patients to those in healthy controls, and to study the relationship between the proximal volume responses, antral filling and vagal neuropathy. We compared 14 consecutively recruited patients with type 1 diabetes mellitus (DM) to 18 healthy controls (HC) with respect to meal-induced gastric volume response assessed by a barostat, antral area recorded by ultrasound, and vagal tone assessed by respiratory sinus arrhythmia (RSA). Meal-induced volume response of the proximal stomach (area under time-volume curve 0-30 min) was significantly (P = 0.04) lower in DM than in HC, 49.4 min.mL +/- 60.7 vs. 114.9 min.mL +/- 100.8. Antral area was significantly larger in DM than in HC, both fasting (4.3 cm2 +/- 1.9 vs. 3.0 cm2 +/- 0.9) and 10 min after ingestion of meat soup (11.8 cm2 +/- 3.4 vs. 8.8 cm2 +/- 2.9), P = 0.03 and P = 0.02, respectively. Vagal tone was significantly (P = 0.01) lower in DM than in HC. 3.7 beats min-1 +/- 2.3 vs. 6.1 beats min-1 +/- 2.2. No significant correlation was observed between the proximal volume responses and antral widening. Maximal gastric volume response correlated significantly with vagal tone (r = 0.77, P = 0.002). CONCLUSIONS: patients with diabetes mellitus type 1 have impaired meal-induced volume response, possibly as a consequence of reduced vagal tone.

Wide gastric antrum and low vagal tone in patients with diabetes mellitus type 1 compared to patients with functional dyspepsia and healthy individuals.

Autonomous neuropathy in patients with diabetes is associated with dysmotility and abdominal discomfort. The disturbances resemble to some extent those seen in patients with functional dyspepsia. To gain further insight into the disorders, we compared patients with long-standing diabetes, patients with functional dyspepsia, and healthy individuals with respect to abdominal symptoms, width of gastric antral area, and autonomic nerve function. We investigated 42 type I diabetic outpatients by structured interview for abdominal discomfort, ultrasonography of the gastric antrum, assessment of vagal and sympathetic nerve function by respiratory sinus arrhythmia and skin conductance, and measurement of blood sugar and HbA1c. Immediately after a standard meal of soup with meat, 21 (50%) of the 42 patients with diabetes complained of abdominal discomfort (pain, bloating, fullness), which was significantly less frequent (95% CI of difference 0.03-0.5) than previously seen in patients with functional dyspepsia (76%), and significantly more frequent (95% CI of difference 0.3-0.6) than that seen in healthy individuals (4%). Bloating was the most marked postprandial complaint. Mean fasting antral area was significantly wider in patients with diabetes (mean 4.9 cm2, SD 1.7) compared to healthy individuals (mean 3.5 cm2, SD 1.2), 95% CI of difference 0.6-2.2 cm2. Mean postprandial antral area was 14.8 cm2 (SD 4.6) in the patients with diabetes, which is insignificantly wider than in patients with functional dyspepsia (mean 13.0 cm2, SD 4.0) but significantly wider (95% CI of difference 1.9-6.5 cm2) than that seen in healthy individuals (mean 10.6 cm2, SD 3.8). The mean respiratory sinus arrhythmia was 0.7 beats/min (SD 0.7) in the patients with diabetes, which was insignificantly lower than that seen in patients with functional dyspepsia (2.1 beats/min, SD 4.5), and significantly lower (99% CI of difference 3.8-7.1 beats/min) compared to healthy individuals (6.2 beats/min, SD 3.8). It is concluded that patients with diabetes have a wider gastric antrum and more discomfort after a meal than healthy individuals. Compared to patients with functional dyspepsia, patients with diabetes have a wider postprandial antrum but fewer symptoms. The very low vagal tone seen in patients with diabetes may play an important role in the pathogenesis of their gastric motility disturbance and postprandial abdominal discomfort.

Gastric relaxation in response to a soup meal in healthy subjects. A study using a barostat in the proximal stomach.

BACKGROUND: Meal-induced relaxation of the proximal stomach can be investigated by means of a barostat. Using a standard liquid meat soup that elicits symptoms and a wide antrum in patients with functional dyspepsia, we aimed at finding the best meal size and fat load for studying gastric relaxation. METHODS: In the first trial 200 ml and 500 ml meat soup (1 g fat/200 ml) was given to six healthy individuals. In the second trial a constant volume of soup (200 ml) containing graded amounts of fat (1, 10, and 20 g/200 ml) was given to seven healthy individuals. Gastric relaxation was investigated for 1 h after consumption of the soup. A sagittal cross-sectional antral was assessed ultrasonographically every 10 min, and abdominal discomfort was scored. RESULTS: Overall, a positive response (volume increase of 30 ml or more within 5 min after consumption of the meal) was found in 26 of 30 (87%) investigations. Individual maximal responses ranged from 38 to 482 ml (mean, 180 ml +/- 128). Area under the time-volume curve (AUC) was similar after 200 and 500 ml soup (mean, 100 ml/30 min and 107 ml/30 min, respectively). AUC increased with increasing fat content, with a significant difference between the low-fat and high-fat meal (p < 0.05). The barostat bag induced fed-state antral contractions in most individuals (p < 0.001). There was a negative correlation between AUC and postprandial abdominal discomfort (p = 0.04). CONCLUSIONS: The barostat is a sensitive technique for detecting gastric relaxation, also in response to our standard meat soup meal. The postprandial relaxation response in healthy individuals in dependent on the fat content of the meal. The barostat bag may alter gastric motor activity. Abdominal discomfort after soup ingestion may be related to poor gastric relaxation.