Postprandial Antral Area Research Articles

Gastroparesis among Type 1 and Type 2 Diabetic Patients in the United Arab Emirates

Aims: Delayed gastric emptying (GE) may have a major effect on the management of diabetic pa- tients by causing upper gastrointestinal symptoms, impaired oral drug absorption and contri- buting to poor blood sugar control. Although the United Arab Emirates (UAE) has one of the high- est prevalence of diabetes in the world, studies focusing on the prevalence of diabetes gastropare- sis among these diabetics have never been reported previously. The aim of this study was to in- vestigate gastroparesis among randomly selected Emirati type 1 and type 2 diabetic patients re- ferred to a national diabetes center in the UAE. Methods: The study was designed as a controlled, single-blinded study. Using a standardized ultrasound technique, GE was studied in thirty-one randomly recruited type 1 and type 2 diabetic patients and ten normal healthy volunteers. The gastric emptying rate (GER) was estimated and expressed as the percentage reduction in antral cross-sectional area from 15 to 90 min after the ingestion of a semisolid breakfast meal. Results: In comparison to healthy volunteers, diabetic patients showed overall significantly wider mean values of the fasting as well as the postprandial antral areas. The mean value of GER in these Emirati diabetic patients was estimated at 17%, which was less than half of that in the healthy volunteers (50%). Statistically the difference was highly significant (p 32%. Consequently, 71% (22 of 31) of the diabetic patients in this study had more or less pronounced delays in GER (gastroparesis). Conclusions: The results from the present study indicate a higher prevalence of gastroparesis among randomly selected Emirati type 1 and type 2 diabetic patients, than in any other study previously published around the world. This is in line with previous reports about the high prevalence of diabetes complica- tions among UAE diabetics. A larger study is needed to confirm these results. * Corresponding author.

Gastric emptying in myotonic dystrophic patients

Background. Myotonic dystrophy is often associated with digestive symptoms that can precede the clinical appearance of skeletal muscle involvement. Although motility disorders may be observed in these patients at any level of the gastrointestinal tract, upper gastrointestinal symptoms have up to now usually been considered to be due to oesophageal rather than gastric dysmotility. Aims. To evaluate: a) gastric emptying in myotonic dystrophic patients without dyspeptic symptoms, and b) relationship between gastric emptying and severity and duration of the disease. Patients and Methods. Gastric emptying was evaluated in 11 non-dyspeptic dystrophic patients and in 22 healthy volunteers by means of computerised ultrasound scan, assessing the variation in the antral area over time after ingestion of a meal. Results. The final emptying time was higher in patients than in healthy volunteers (373′±35′ vs 270′±47′; p<O. 001]. Basal and maximal postprandial antral areas were similar in the two groups. There was a significant correlation between gastric emptying and the duration of the disease (r s=0. 62; p=0.04). No relationship was found between gastric emptying and severity of the disease. Conclusions. Gastric emptying may be abnormally delayed in myotonic dystrophy patients, even in absence of dyspeptic symptoms. This delay is correlated with duration but not with severity of the disease. However, there is no difference in either basal or maximal postprandial antral areas between myotonic dystrophy patients and healthy volunteers.

Influence of a 5HT1 receptor agonist on gastric accommodation and initial transpyloric flow in healthy subjects

Sumatriptan, a 5HT1 receptor agonist, inhibits antral motor activity, delays gastric emptying and relaxes the gastric fundus. The aim of this study was to characterize the effect of sumatriptan on transpyloric flow and gastric accommodation during and immediately after ingestion of a liquid meal using duplex sonography. Ten healthy subjects were investigated twice on separate days. In random order either sumatriptan 6 mg (Imigran 0.5 mL) or a placebo were given s.c. 15 min before ingesting 500 mL of a meat soup. The subjects were examined during the 3-min period before ingestion of the liquid meal, the 3-min spent drinking the meal and 10 min postprandially. Sumatriptan caused a significant widening of both the gastric antrum (P=0.02) and the proximal stomach (P=0.01) 10 min postprandially as compared with placebo. It caused no significant differences in time to initial gastric emptying (P=0.2), but significantly delayed commencement of peristaltic-related transpyloric flow (P=0.04). Sumatriptan had no significant effect on mean abdominal symptom scores, but after sumatriptan there was a significant negative correlation between width of postprandial antral area and postprandial nausea and between width of postprandial antral area and postprandial bloating. We therefore conclude that sumatriptan causes a postprandial dilatation of both the distal and the proximal stomach with no change in dyspeptic symptoms nor in length of time to first gastric emptying. Time to commencement of peristaltic-related emptying is delayed.

Measurement of gastric emptying by standardized real-time ultrasonography in healthy subjects and diabetic patients.

The aim of this study was to simplify and standardize a reproducible, well-tolerated and clinically applicable method for the assessment of gastric emptying rate by real-time ultrasonography. A total of 33 subjects were examined, including 19 healthy subjects and 14 patients with insulin-dependent diabetes mellitus and clinically suspected delayed gastric emptying. Measurements of the gastric antrum were taken in the supine position and in relation to internal landmarks to obtain a standardized cross-sectional image producing the area of a selected slice of the antrum. Diabetic patients were examined on the condition that the fasting blood glucose level was 3.5 to 9.0 mmol/l. Gastric emptying rate was estimated and expressed as the percentage reduction in antral cross-sectional area from 15 to 90 min after the ingestion of a standardized semisolid breakfast meal (300 g rice pudding, 330 kcal). Interobserver and intraobserver measurement errors were assessed, as was the significance of age and sex on gastric emptying. In comparison to healthy subjects, diabetic patients showed significantly wider median values of the 90 min postprandial antral area, but only a mild tendency toward greater dilation of the gastric antrum prior to and 15 min after meal ingestion. The median value of gastric emptying rate in these diabetic patients was estimated at 29%, which was less than half of that in the healthy subjects (63%). Statistically the difference was highly significant. Interpersonal variability of gastric emptying rate and antral areas was large for both groups. Measurements of gastric emptying rate gave highly reproducible results on separate days and from different observers (interobserver systematic measurement error 0.3% and random measurement error 10.9%; intraobserver systematic measurement error 3.6% and random measurement error 9.5%). No difference in gastric emptying rate was found related to age or sex. We conclude that the use of standardized real-time ultrasonography to determine gastric antral cross-sectional area in a single section of the stomach is a valid method for estimating gastric emptying rate.

Relation between postprandial satiation and antral area in normal subjects

The factors influencing appetite in humans are poorly understood. There is a weak relation between appetite and gastric emptying in normal subjects. Recent studies have shown that fasting and postprandial antral areas increase in patients with functional dyspepsia compared with normal subjects. We evaluated the hypothesis that antral area, and hence antral distention, is a significant determinant of postprandial fullness. Fourteen normal subjects had simultaneous measurements of gastric emptying by scintigraphy and antral area by ultrasound after ingestion of 350 mL 20% glucose. Fullness and hunger were assessed by visual analog scales. Measurements of the gastric-emptying half time (t1/2) by scintigraphy and ultrasound were not significantly different (129.6 +/- 11.8 min compared with 115.6 +/- 11.4 min). Fullness increased (P < 0.001) and hunger decreased (P < 0.001) after the drink. Both fullness and the magnitude of the increase in fullness after the drink were related to antral area (r > 0.56, P < 0.05), the increase in antral area (r > 0.59, P < 0.05), and the scintigraphic content of the distal stomach (r > 0.57, P < 0.05), but not to the ultrasound or scintigraphic t1/2 values. In contrast, hunger and the magnitude of the decrease in hunger after the drink were not related to either antral area, the increase in antral area, or the rate of gastric emptying. We conclude that postprandial fullness, but not hunger, was closely related to antral distention in normal subjects.

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.

Effect of Glyceryl Trinitrate on Antral Motility and Symptoms in Patients with Functional Dyspepsia

Nitric oxide (NO) is considered to be an important physiologic non-adrenergic, non-cholinergic vagal transmitter in the neural regulation of gastric adaptive relaxation, which accommodates the gastric fundus to ingested food. Ten consecutive patients with functional dyspepsia (FD) and erosive prepyloric changes were studied twice on separate days, once without drug administration and once after intake of one tablet of glyceryl trinitrate (GTN), 2.6 mg, 2 h before ingestion of 500 ml meat soup. Width of antral area, amplitude (maximal area reduction as fraction of relaxed area), and frequency of antral contractions were measured ultrasonographically in standardized sections. Postprandial abdominal discomfort was scored. Without GTN, postprandial antral area and symptom scores were positively correlated (r = 0.64, p = 0.05). After administration of GTN, antral area both fasting and 10 min postprandially was reduced (p = 0.02 and p = 0.01, respectively), whereas amplitude and motility index of antral contractions tended to increase (p = 0.07 and p = 0.09, respectively). Abdominal discomfort was not significantly reduced by GTN (p = 0.13). The results suggest a relationship between postprandial antral distension and discomfort. Moreover, GTN (by generation of NO) reduced abnormal antral filling in patients with FD.