Lipase Supplementation before a High-Fat Meal Reduces Perceptions of Fullness in Healthy Subjects.

BACKGROUND/AIMS: Postprandial symptoms of fullness and abdominal discomfort are common after fatty meals. Gastric lipases hydrolyze 10% to 20% of dietary triglycerides during the stomach trituration period of digestion. The aim of this study was to evaluate the effects of acid-resistant lipase on upper gastrointestinal symptoms, including fullness and bloating, as well as on gastric myoelectrical activity after healthy subjects ingested a high-fat, liquid meal. METHODS: This study utilized a double-blind, placebo-controlled, crossover design with 16 healthy volunteers who ingested either a capsule containing 280 mg of acid-resistant lipase or a placebo immediately before a fatty meal (355 calories, 55% fat). Participants rated their stomach fullness, bloating, and nausea before and at timed intervals for 60 minutes after the meal. Electrogastrograms were obtained to assess the gastric myoelectrical activity. RESULTS: Stomach fullness, bloating, and nausea increased significantly 10 minutes after ingestion of the fatty meal (p<0.01), whereas normal gastric myoelectrical activity decreased and tachygastria increased (p<0.05). With lipase, reports of stomach fullness were significantly lower compared with placebo (p<0.05), but no effect on gastric myoelectrical activity or other upper gastrointestinal symptoms was observed. CONCLUSIONS: The high-fat meal induced transient fullness, bloating, nausea, and tachygastria in healthy individuals, consistent with postprandial distress syndrome. Acid-resistant lipase supplementation significantly decreased stomach fullness.

Enhanced perceptions of control and predictability reduce motion-induced nausea and gastric dysrhythmia.

Nausea is a debilitating condition that is typically accompanied by gastric dysrhythmia. The enhancement of perceived control and predictability has generally been found to attenuate the physiological stress response. The aim of the present study was to test the effect of these psychosocial variables in the context of nausea, motion sickness, and gastric dysrhythmia. A 2x2, independent-groups, factorial design was employed in which perceived control and predictability were each provided at high or low levels to 80 participants before exposure to a rotating optokinetic drum. Ratings of nausea were obtained throughout a 6-min baseline period and a 16-min drum rotation period. Noninvasive recordings of the electrical activity of the stomach called electrogastrograms were also obtained throughout the study. Nausea scores were significantly lower among participants with high control than among those with low control, and were significantly lower among participants with high predictability than among those with low predictability. Estimates of gastric dysrhythmia obtained from the EGG during drum rotation were significantly lower among participants with high predictability than among those with low predictability. A significant interaction effect of control and predictability on gastric dysrhythmia was also observed, such that high control was only effective for arresting the development of gastric dysrhythmia when high predictability was also available. Stronger perceptions of control and predictability may temper the development of nausea and gastric dysrhythmia during exposure to provocative motion. Psychosocial interventions in a variety of nausea contexts may represent an alternative means of symptom control.

Protein and ginger for the treatment of chemotherapy-induced delayed nausea.

BACKGROUND: Nausea that develops during the period that begins 24 hours after the administration of chemotherapy is called delayed nausea, and occurs in many patients with cancer. Meals high in protein decrease the nausea of motion sickness and pregnancy, possibly by reducing gastric dysrhythmias. Ginger also has antinausea properties. OBJECTIVES: To explore the use of protein meals with ginger for the treatment of the delayed nausea of chemotherapy. DESIGN: Twenty-eight (28) patients with cancer receiving chemotherapy for the first time were assigned to 1 of 3 groups. For 3 days beginning the day after their chemotherapy, Control Group patients continued with their normal diet, Protein Group patients consumed a protein drink and ginger twice daily, and High Protein Group patients consumed a protein drink with additional protein and ginger twice daily. OUTCOME MEASURES: Patients recorded in a diary each day whether they had experienced nausea, whether their nausea had been frequent, whether their nausea had been bothersome, and whether they had needed any antiemetic medication. Gastric myoelectrical activity was assessed in 5 patients before and after ingestion of a high protein meal and ginger. RESULTS: Reports of nausea, frequent nausea, and bothersome nausea were significantly less common among High Protein Group patients than among Control and Protein Group patients. Furthermore, significantly fewer patients in the High Protein Group used antiemetic medication. Differences between the Protein and Control groups were not statistically significant. In the 5 patients who had tests of gastric myoelectrical activity performed, a significant decrease in gastric dysrhythmia occurred after ingestion of the protein and ginger. CONCLUSIONS: High protein meals with ginger reduced the delayed nausea of chemotherapy and reduced use of antiemetic medications. Protein with ginger holds the potential of representing a novel, nutritionally based treatment for the delayed nausea of chemotherapy.

Susceptibility to nausea and motion sickness as a function of the menstrual cycle.

PURPOSE: The present study examined whether susceptibility to nausea and other symptoms of vection-induced motion sickness vary as a function of phase of the menstrual cycle, as research findings in this area are sparse and contradictory. DESIGN: Ninety young women (42 current users of oral contraceptives) were exposed to a rotating optokinetic drum during the peri-menses or peri-ovulatory phase of the menstrual cycle in an independent-groups, quasi-experimental design. Nausea and motion sickness symptoms were assessed using the Nausea Profile (NP) and the Subjective Symptoms of Motion Sickness (SSMS) questionnaire. RESULTS: Among women not on oral contraceptives, reports of nausea and motion sickness by women in the peri-menses phase were more severe than reports by women in the peri-ovulatory phase. By contrast, among women taking oral contraceptives, reports of nausea and motion sickness did not differ by the same categorical phase of the menstrual cycle. CONCLUSIONS: We speculate that fluctuating estrogen levels over the course of the menstrual cycle may influence the experience of or susceptibility to nausea and motion sickness during illusory self-motion and other nauseogenic contexts.

The effects of manipulating expectations through placebo and nocebo administration on gastric tachyarrhythmia and motion-induced nausea.

BACKGROUND: Interest in the role of expectation in the development of nausea and other adverse conditions has existed for decades. The purpose of this study was to examine the effects of manipulating expectations through the administration of placebos and nocebos on nausea and gastric tachyarrhythmia provoked by a rotating optokinetic drum. METHOD: Seventy-five participants were assigned to one of three groups. Positive-expectancy group participants were given placebo pills that would allegedly protect them against the development of nausea and motion sickness. Negative-expectancy group participants were given the same pills as nocebos; they were led to believe there was a tendency for them to make nausea somewhat worse. Placebo-control group participants were told the pills were indeed placebos that would have no effect whatsoever. RESULTS: Subjective symptoms of motion sickness were significantly lower among negative-expectancy group participants than positive-expectancy and placebo-control group participants (p<0.05). Gastric tachyarrhythmia, the abnormal stomach activity that frequently accompanies nausea, was also significantly lower among negative-expectancy group participants than positive-expectancy and Placebo-Control Group participants during drum rotation (p<.05) [corrected] CONCLUSIONS: Inducing negative expectations through nocebo administration reduced nausea and gastric dysrhythmia during exposure to provocative motion, whereas positive placebos were ineffective for preventing symptom development. That manipulation of expectation affected gastric physiological responses as well as reports of symptoms, suggests an unspecified psychophysiological mechanism was responsible for the observed group differences. These results also suggest that patients preparing for difficult medical procedures may benefit most from being provided with detailed information about how unpleasant their condition may become.

Sickness and satiety: physiological mechanisms underlying perceptions of nausea and stomach fullness.

The pathophysiology of nausea and the physiological mechanisms underlying perceptions of stomach emptiness and fullness are not clearly understood, but several potentially important factors have been identified. Gastric dysrhythmias are believed to contribute to the subjective experience of nausea and may also be involved with perceptions of stomach emptiness, hunger, and even dyspepsia symptoms like bloating and early satiety. Normal gastric neuromuscular function is more evident in the absence of nausea and is also thought to be related to feelings of satiety or comfortable stomach fullness. Autonomic and endocrine influences may also play a critical role in the pathophysiology of nausea and abnormal perceptions of stomach emptiness or fullness. Achieving a better understanding of the gastric neuromuscular and neurohormonal influences on perceptions arising from the viscera may prove invaluable in the development of novel treatments for such conditions as unexplained nausea, functional dyspepsia, and obesity.

Relationship between temporal changes in cardiac parasympathetic activity and motion sickness severity.

Chemotherapy-induced nausea has been associated with a time-related decrease in cardiac parasympathetic activity. We tested the hypothesis that a time-related decrease in cardiac parasympathetic activity would also be associated with nausea and other motion sickness symptoms during illusory self-motion (vection). Fifty-nine participants (aged 18-34 years: 25 male) were exposed to a rotating optokinetic drum to induce vection. Symptoms of motion sickness and an estimate of cardiac parasympathetic activity (respiratory sinus arrhythmia; RSA) were obtained at baseline and throughout a drum-rotation period. As expected, motion sickness symptoms increased and RSA decreased over time during drum rotation. Moreover, greater decreases in RSA over time correlated with greater motion sickness severity. These results suggest that a time-related decrease in cardiac parasympathetic activity may be an important correlate of nausea and motion sickness across different evocative contexts.

Spatial task performance, sex differences, and motion sickness susceptibility.

There are substantial individual differences in susceptibility to motion sickness, yet little is known about what mediates these differences. Spatial ability and sex have been suggested as possible factors in this relationship. 89 participants (57 women) were administered a Motion Sickness Questionnaire that assesses motion sickness susceptibility, a Water-level Task that gauges sensitivity to gravitational upright, and a Mental Rotation Task that tests an individual's awareness of how objects typically move in space. Significant sex differences were observed in performance of both the Water-level Task (p<.01), and the Mental Rotation Task (p<.005), with women performing less accurately than men. Women also had significantly higher scores on the Motion Sickness Questionnaire (p<.005). Among men, but not women, significant negative relationships were observed between Water-level Task performance and Motion Sickness Questionnaire score (p<.001) and between Mental Rotation Task performance and Motion Sickness Questionnaire score (p<.005). In conclusion, women performed significantly more poorly than men did on the spatial ability tasks and reported significantly more bouts of motion sickness. In addition, men showed a significant negative relationship between spatial ability and motion sickness susceptibility.