Dietary factors in functional dyspepsia

Psychometric evaluation of an experience sampling method-based patient-reported outcome measure in functional dyspepsia

BACKGROUND

Due to important biases, conventional end-of-day and end-of-week assessment methods of gastrointestinal symptoms in functional dyspepsia (FD) are considered suboptimal. Real-time symptom assessment based on the experience sampling method (ESM) could be a more accurate measurement method. This study aimed to evaluate validity and reliability of an ESM-based patient-reported outcome measure (PROM) for symptom assessment in FD.

METHODS

Thirty-five patients with FD (25 female, mean age 44.7 years) completed the ESM-based PROM (a maximum of 10 random moments per day) and an end-of-day symptom diary for 7 consecutive days. On day 7, end-of-week questionnaires were completed including the Nepean Dyspepsia Index (NDI) and Patient Assessment of Gastrointestinal Symptom Severity Index (PAGI-SYM).

KEY RESULTS

Experience sampling method and corresponding end-of-day scores for gastrointestinal symptoms were significantly associated (ICCs range 0.770-0.917). However, end-of-day scores were significantly higher (Δ0.329-1.031) than mean ESM scores (p < 0.05). Comparing ESM with NDI and PAGI-SYM scores, correlations were weaker (Pearson's r range 0.467-0.846). Cronbach's α coefficient was good for upper gastrointestinal symptoms (α = 0.842). First half-week and second half-week scores showed very good consistency (ICCs range 0.913-0.975).

CONCLUSION AND INFERENCES

Good validity and reliability of a novel ESM-based PROM for assessing gastrointestinal symptoms in FD patients was demonstrated. Moreover, this novel PROM allows to evaluate individual symptom patterns and can evaluate interactions between symptoms and environmental/contextual factors. ESM has the potential to increase patients' disease insight, provide tools for self-management, and improve shared decision making. Hence, this novel tool may aid in the transition toward personalized health care for FD patients.

The relationship between fruit and vegetable intake with functional dyspepsia in adults

INTRODUCTION

The association of fruit and vegetables with functional dyspepsia (FD) has been less studied, especially in Middle Eastern populations. This study investigated the relationship between fruit and vegetable consumption with FD and its related symptoms among a large group of Iranian adults.

METHODS AND MATERIALS

This cross-sectional research was conducted on 3362 middle-age participants. Usual dietary intakes, including fruit and vegetable intake, during the last year were assessed using a validated 106-item dish-based food frequency questionnaire (FFQ). A modified Persian version of the Rome III questionnaire was used for assessment of FD.

RESULTS

The prevalence of FD among study participants was 14.5%. After adjustment for confounders, the highest energy-adjusted tertile of fruit consumption was related to 32% lower risk of FD, compared to the lowest intake (OR = 0.68, 95% CI:0.51-0.90). Fruit consumption was also significantly related to lower risk of early satiation (OR = 0.67, 95% CI:0.54-0.85) and post-prandial fullness (OR = 0.75, 95% CI:0.61-0.92). Vegetable consumption was not related to the risk of FD in all models. Men who were in the third tertile of fruit and the third tertile vegetable consumption had lower risk of FD compared to the first tertile; but, in women, just fruit consumption was related to the reduced risk of FD, after adjustment for all confounders.

CONCLUSION

We found an inverse association between fruit intake and dyspepsia symptoms. In addition, high consumption of fruit was related to lower odds of early satiation and post-prandial fullness. Higher intake of vegetables was associated with lower risk of FD, only in men.

Impaired decision-making under risk in patients with functional dyspepsia

INTRODUCTION

The cognitive processing in patients with functional dyspepsia (FD) has not been well established. Decision-making is an important component of cognitive function. Most brain regions involved in decision-making are abnormal in FD patients. This study aimed to investigate the decision-making under ambiguity and risk in FD patients.

METHODS

We recruited 40 FD patients meeting Rome III criteria and 40 healthy controls (HCs) matched for age, sex, marital status, and education level. The Hamilton Anxiety Scale (HAMA) and the 17-item Hamilton Depression Scale (HAMD-17) were used to evaluate their anxiety and depression emotions. The Iowa Gambling Task (IGT) and Game of Dice Task (GDT) were used to evaluate decision-making under ambiguity and risk, respectively. Helicobacter pylori status, disease duration, dyspeptic symptom score, and the Nepean Dyspepsia Life Quality Index (NDLQI) were obtained from all patients.

RESULTS

In IGT, FD patients had a lower total net score, chose more adverse choices, and showed a slower response to change their behavior than HCs. However, there was no significant difference in the net score of the first 2 blocks between the two groups. In GDT, FD patients had a lower total net score, higher risk score, and lower use of negative feedback than HCs. In addition, FD patients showed better GDT performance than those without early satiation.

CONCLUSIONS

FD patients showed impaired decision-making under risk. The deficiency might be related to dyspeptic symptoms of FD patients.

Combined Healthy Lifestyle Is Inversely Associated with Upper Gastrointestinal Disorders among Iranian Adults

OBJECTIVE

Although lifestyle-related factors have separately been examined in relation to functional gastrointestinal disorders (FGIDs), there is no epidemiological data on the combined association of lifestyle factors with these conditions. We aimed to examine how combinations of several lifestyle factors were associated with functional dyspepsia (FD), its symptoms, and gastroesophageal reflux disease (GERD) in a large group of Iranian adults.

DESIGN, SETTING, AND SUBJECTS

In a cross-sectional study on 3,363 Iranian adults, we calculated the "healthy lifestyle score" for each participant by summing up the binary score given for 5 lifestyle factors, including dietary habits, dietary intakes, psychological distress, smoking, and physical activity. A dish-based 106-item semi-quantitative validated food frequency questionnaire, General Practice Physical Activity Questionnaire, General Health Questionnaire, and other pre-tested questionnaires were used to assess the components of healthy lifestyle score. To assess FGIDs, a validated Persian version of ROME III questionnaire was used.

RESULTS

After adjustment for potential confounders, we found that individuals with the highest score of healthy lifestyle had 79 and 74% lower odds of FD (OR: 0.21; 95% CI: 0.05-0.92) and GERD (OR: 0.26; 95% CI: 0.09-0.69), respectively, compared with those with the lowest score. They were also less likely to have early satiation (OR: 0.28; 95% CI: 0.11-0.73), postprandial fullness (OR: 0.22; 95% CI: 0.09-0.50), and epigastric pain (OR: 0.44; 95% CI: 0.21-0.92). In addition to the combined healthy lifestyle score, low levels of psychological distress, a healthy diet, healthy dietary habits, and nonsmoking were separately and protectively associated with FGIDs.

CONCLUSION

We found that adherence to a healthy lifestyle was associated with lower odds of GERD, FD, and its symptoms in this group of Iranian adults, in a dose-response manner. Individual lifestyle-related factors were also associated with these conditions.

Healthy lifestyle score and irritable bowel syndrome: A cross-sectional study in adults

BACKGROUND

Lifestyle modifications play an important role in the management of irritable bowel syndrome (IBS), but there is limited information on any associations of combined lifestyle-related factors with IBS in Middle Eastern populations. We, therefore, assessed the associations of a "lifestyle score," in analogy to lifestyle scores applied in studies of other disorders, with IBS in adults.

METHODS

In a cross-sectional study on 3363 Iranian adults, a healthy lifestyle score (HLS) was constructed using information about dietary habits, dietary intake, physical activity, smoking status, and psychological distress, which was collected using validated questionnaires. A modified version of the Rome III questionnaire (in Persian) was used to diagnose IBS and its subtypes.

KEY RESULTS

Individuals with the highest HLS had a 65% lower odds of having IBS compared with those in the lowest category (OR: 0.35; 95% CI: 0.26-0.48). Participants with healthy dietary habits, including regular meal pattern, slow/moderate eating rate, moderate intra-meal fluid consumption, moderate/long meal-to-sleep interval, and low/moderate consumption of fatty foods, had significantly lower odds of having IBS compared with those with unhealthy dietary habits (OR: 0.81; 95% CI: 0.69-0.96). Moreover, individuals with lower levels of psychological distress, compared with those with higher levels of distress, had significantly lower odds of IBS (OR: 0.49; 95% CI: 0.40-0.60).

CONCLUSIONS AND INFERENCES

Our data suggest that having an overall "healthy lifestyle" is related to substantially reduced odds of IBS, suggesting that adhering to a healthy lifestyle pattern, including dietary habits, diet quality, physical activity, smoking, and psychological distress, can be considered as a key management strategy for IBS.

Sustained proton pump inhibitor deprescribing among dyspeptic patients in general practice: a return to self-management through a programme of education and alginate rescue therapy. A prospective interventional study

Background

Dyspepsia guidelines recommend that patients treated with proton pump inhibitors (PPIs) should step down to the lowest effective dose or return to self-care, but rebound hyperacidity can make this difficult. Many patients continue on PPIs in the long term, which may lead to safety and financial implications.

Aim

To determine if a nurse-led educational support programme and rescue therapy for rebound symptoms can help patients achieve a sustained reduction in PPI use.

Design & setting

A prospective interventional study was conducted at 26 surgeries across the UK.

Method

Adult patients, treated with PPIs for ≥2 consecutive months with an active repeat prescription, were invited to a 20-minute dyspepsia clinic appointment with a trained nurse adviser. An action plan to reduce and/or stop their PPI usage was agreed and alginate supplied for the self-management of rebound symptoms. After 12 months, PPI status was reviewed and prescribing cost savings calculated.

Results

After 12 months, 75.1% of 6249 eligible patients stepped down or off PPIs (35.3% stepped off; 5.0% stepped down then off; 34.8% stepped down only), while 8.7% of patients had reverted to their original PPI dose. PPI prescriptions fell from 89 915 to 45 880 and alginate prescriptions increased from 2405 to 6670. An average of 1.7 bottles (500 ml each) of alginate were used per patient who stepped down or off. Estimated annual cost-saving on prescriptions was £31 716.30.

Conclusion

A programme of education and short-term rebound symptom management helped the majority of patients to successfully step down or off PPIs, significantly reducing the potential risks associated with chronic therapy.

Development of a real-time patient-reported outcome measure for symptom assessment in patients with functional dyspepsia using the experience sampling method

BACKGROUND

Patient-reported outcome measures (PROMs) are used to assess symptoms in patients with functional dyspepsia (FD). Current end-of-day questionnaires have several limitations including sensitivity to recall and ecological bias. The experience sampling method (ESM) is characterized by random and repeated assessments across momentary states in daily life and therefore less sensitive to these limitations. This study describes the development of a novel PROM based on ESM technology.

METHODS

An initial draft of the PROM was developed based on literature. Focus group interviews with FD patients according to Rome IV criteria, and an expert meeting with international opinion leaders in the field of functional gastrointestinal disorders were conducted in order to select items for the PROM. Cognitive interviews were performed to evaluate patients' understanding of the selected items and to create the definitive PROM.

KEY RESULTS

A systematic literature search revealed 59 items across four domains (ie, physical status; mood and psychological factors; context and environment; and nutrition, medication, and substance use). After patient focus group interviews and an international expert meeting, the number of items was reduced to 33. Cognitive interviews resulted in some minor linguistic changes in order to improve patients' understanding.

CONCLUSIONS AND INFERENCES

A novel digital ESM-based PROM for real-time symptom assessment in patients with functional dyspepsia was developed. This novel PROM has the potential to identify individual symptom patterns and specific triggers for dyspeptic symptoms, and optimize treatment strategies.

Role of the Duodenum in the Pathogenesis of Functional Dyspepsia: A Paradigm Shift

Functional dyspepsia (FD) is a common disorder characterized by chronic epigastric pain or burning, or bothersome postprandial fullness or early satiation, without a definitive organic cause. The pathogenesis of FD is likely heterogeneous. Classically, motor disorders, visceral hypersensitivity, and brain-gut interactions have been implicated in the pathophysiology of FD, but recently an important role for chronic low-grade inflammation and infection in FD has been reported and confirmed. Duodenal low-grade inflammation is frequently observed in FD in those with and without documented previous gastroenteritis. Duodenal eosinophils and in some cases mast cells may together or separately play a key role, and immune activation (eg, circulating homing small intestinal T cells) has been observed in FD. Low-grade intestinal inflammation in patients with FD may provoke impairment in motor-sensory abnormalities along the gastrointestinal neural axis. Among FD patients, the risk of developing dyspeptic symptoms after a bout of gastroenteritis is 2.54 (95% CI, 1.76–3.65) at more than 6 months after acute gastroenteritis. Gut host and microbial interactions are likely important, and emerging data demonstrate both quantitative and qualitative changes of duodenal mucosal and fecal microbiota in FD. Food antigens (eg, wheat proteins) may also play a role in inducing duodenal inflammation and dyspepsia. While causation is not established, the hypothesis that FD is a disorder of microscopic small intestinal inflammation in a major subset is gaining acceptance, opening the possibility of novel treatment approaches that may be able to alter the natural history of the disorder.

Systematic review: Disease-specific instruments to assess gastrointestinal symptoms in functional dyspepsia

BACKGROUND

Functional dyspepsia (FD) is a common functional gastrointestinal disorder with incompletely understood pathophysiology and heterogeneous symptom presentation. Assessment of treatment efficacy in FD is a methodological challenge as response to treatment must be assessed primarily by measuring subjective symptoms. Therefore, the use of patient-reported outcome measures (PROMs) is recommended by regulatory authorities to assess gastrointestinal symptoms in clinical trials for FD. In the last decades, a multitude of outcome measures has been developed. However, currently no PROM has been approved by the regulatory authorities, and no consensus has been reached with regard to the most relevant outcome measure in FD.

PURPOSE

This systematic review discusses the available disease-specific outcome measures for assessment of FD symptoms with psychometric validation properties, strengths, and limitations. Moreover, recommendations for use of current available outcome measures are provided, and potential areas of future research are discussed.

Food and functional dyspepsia: a systematic review

BACKGROUND

Functional dyspepsia (FD) is a debilitating functional gastrointestinal disorder characterised by early satiety, post-prandial fullness or epigastric pain related to meals, which affects up to 20% of western populations. A high dietary fat intake has been linked to FD and duodenal eosinophilia has been noted in FD. We hypothesised that an allergen such as wheat is a risk factor for FD and that withdrawal will improve symptoms of FD. We aimed to investigate the relationship between food and functional dyspepsia.

METHODS

Sixteen out of 6451 studies identified in a database search of six databases met the inclusion criteria of studies examining the effect of nutrients, foods and food components in adults with FD or FD symptoms.

RESULTS

Wheat-containing foods were implicated in FD symptom induction in six studies, four of which were not specifically investigating gluten and two that were gluten-specific, with the implementation of a gluten-free diet demonstrating a reduction in symptoms. Dietary fat was associated with FD in all three studies that specifically measured this association. Specific foods reported as inducing symptoms were high in either natural food chemicals, high in fermentable carbohydrates or high in wheat/gluten. Caffeine was associated with FD in four studies, although any association with alcohol was uncertain.

CONCLUSIONS

Wheat and dietary fats may play key roles in the generation of FD symptoms and reduction or withdrawal eased symptoms. Randomised trials investigating the roles of gluten, FODMAPs (fermentable oligosaccharide, disaccharide, monosaccharide and polyols) and high fat ingestion and naturally occurring food chemicals in the generation of functional dyspepsia symptoms are warranted and further investigation of the mechanisms is now required.

Total diet, individual meals, and their association with gastroesophageal reflux disease

Background: To identify the association of total diet and individual meals with gastroesophageal reflux disease (GERD).

Methods: This age- and sex-matched case-control study was carried out among 217 subjects (106 cases and 111 controls). Data were collected using a demographic questionnaire and a GERD checklist and a 3-day food record.

Results: Cases consumed more fat (median: 26.3 [3.2-71.5] g vs. 21.8 [4.3-58.1] g; P=0.04)and more energy percent form carbohydrates (median: 72.5 [0-100] vs. 69.0 [0-100]; P=0.02)at lunch, and less energy (median: 129.5 kcal [0-617.6] vs. 170.5 kcal [0-615.7]; P=0.01) and protein (2.4 [0-19.4] g vs. 3.1 [0-21.8] g; P=0.01) at evening snack, compared to controls.The volume of food was significantly different between the two group only at lunch (median:516 [161-1292] g vs. 468 [198-1060] g; P=0.02). The percentage of energy from total dietary protein showed a significant association with GERD after adjusting for confounders (odds ratio[OR]=0.89; 95% CI: 0.81-0.98). Regarding the individual meals, amount of fat consumed at lunch (OR=1.02; 95% CI: 1.00-1.05), and amount of protein intake at evening snack (OR=0.92;95% CI: 0.85-1.00) were significantly associated with GERD. Meanwhile, caloric density and meal frequency did not differ significantly between the two groups.

Conclusion: Amount of fat consumed at lunch is positively associated with GERD, whereas the percentage of energy from total protein and amount of protein intake at evening snack are more likely to be inversely associated with GERD.

Nutritional habits in functional dyspepsia and its subgroups: a comparative study

OBJECTIVE

Research data demonstrating nutritional habits of functional dyspepsia (FD) patients are very limited. This is the first study to evaluate nutritional habits in FD subgroups according to Rome III criteria. Our aim was to evaluate nutritional habits of FD patients and determine the food items that may provoke a dyspepsia symptom.

METHODS

A total of 168 adults with FD and 135 healthy control subjects participated in the study. FD subjects were divided into epigastric pain syndrome (EP-FD), postprandial distress syndrome (PS-FD), mixed (MX-FD) subgroups according to Rome Criteria III. Subjects completed a questionnaire that included a short-form food frequency questionnaire. Furthermore, subjects were asked to list the food items that were causing a dyspepsia symptom.

RESULTS

Functional dyspepsia subjects had a slightly higher BMI (26.1 ± 4.97 kg/m(2)) than control subjects (24.6 ± 4.08 kg/m(2)). The most common symptom triggering foods among all the FD groups were fried and fatty foods (27.1%), hot spices (26.4%), and carbonated drinks (21.8%). In FD subgroups, carbonated drinks were more likely to cause a symptom in PS-FD group (37.3%) than MX-FD (25.7%) and EP-FD (22.1%) groups. There was no difference in frequency of main meals and snacks among any of the groups.

CONCLUSION

Fatty and spicy foods and carbonated drinks were the most common symptom triggering food items in FD group. In subgroups, carbonated drinks and legumes were more likely to cause a symptom in PS-FD. Removing these food items during the course of treatment might help alleviate the symptoms.

Dietary fat intake and functional dyspepsia

A few studies have assessed the effects of fat intake in the induction of dyspeptic symptoms. So, the aim of this study was to review the articles regarding the dietary fat intake and FD. We used electronic database of PubMed to search. These key words were chosen: FD, dietary fat, dyspeptic symptom, energy intake and nutrients. First, articles that their title and abstract were related to the mentioned subject were gathered. Then, full texts of related articles were selected for reading. Finally, by excluding four articles that was irrelevant to subject, 19 relevant English papers by designing clinical trial, cross-sectional, case–control, prospective cohort, and review that published from 1992 to 2012 were investigated. Anecdotally, specific food items or food groups, particularly fatty foods have been related to dyspepsia. Laboratory studies have shown that the addition of fat to a meal resulted in more symptoms of fullness, bloating, and nausea in dyspeptic patients. Studies have reported that hypersensitivity of the stomach to postprandial distension is an essential factor in the generation of dyspeptic symptoms. Small intestinal infusions of nutrients, particularly fat, exacerbate this hypersensitivity. Moreover, evidence showed that perception of gastric distension increased by lipids but not by glucose. Long chain triglycerides appear to be more potent than medium chain triglycerides in inducing symptoms of fullness, nausea, and suppression of hunger. Thus, Fatty foods may exacerbate dyspeptic symptoms. Therefore, it seems that a reduction in intake of fatty foods may useful, although this requires more evaluations.

Relationship between spicy food intake and chronic uninvestigated dyspepsia in Iranian adults

OBJECTIVE

To assess the association between spicy food consumption and chronic uninvestigated dyspepsia (CUD) in a large sample of Iranian adults.

METHODS

In this cross-sectional study we assessed the consumption of spicy foods in 4763 Iranian adults living in Isfahan Province using a dietary habit questionnaire. A modified validated version of the Rome III questionnaire was used to assess CUD-related symptoms. CUD was defined as having one or more of the following characteristics: distressing postprandial fullness, early satiation and/or epigastric pain or epigastric burning at least often during the past three months. Information on meal regularity, meal frequency, intra-meal intake of fluid as well as other potential confounders was also collected.

RESULTS

CUD was prevalent in 15% of the participants. The frequent consumption of spicy foods (≥ 10 times/week) was associated with greater odds of having CUD [odds ratio (OR) 1.64, 95% confidence interval (CI) 1.09-2.49, P < 0.05). This relationship was significant even after adjusted for diet-related practices (OR 1.68, 95% CI 1.01-2.79, P < 0.05). There was a significantly positive association between spicy food consumption and postprandial fullness (OR 1.76, 95% CI 1.29-2.40, P < 0.05) and epigastric pain (OR 1.78, 95% CI 1.30-2.44, P < 0.05). However, no significant relationship was observed between the frequent consumption of spicy foods and early satiation.

CONCLUSIONS

High consumption of spicy foods is associated with greater odds of CUD, frequent postprandial fullness and epigastric pain. Further studies, particularly of a prospective nature, are needed to confirm our findings.

Peripheral mechanisms in appetite regulation

Peripheral mechanisms in appetite regulation include the motor functions of the stomach, such as the rate of emptying and accommodation, which convey symptoms of satiation to the brain. The rich repertoire of peripherally released peptides and hormones provides feedback from the arrival of nutrients in different regions of the gut from where they are released to exert effects on satiation, or regulate metabolism through their incretin effects. Ultimately, these peripheral factors provide input to the highly organized hypothalamic circuitry and vagal complex of nuclei to determine cessation of energy intake during meal ingestion, and the return of appetite and hunger after fasting. Understanding these mechanisms is key to the physiological control of feeding and the derangements that occur in obesity and their restoration with treatment (as shown by the effects of bariatric surgery).

Patterns of dietary behaviours identified by latent class analysis are associated with chronic uninvestigated dyspepsia

To our knowledge, no study has assessed the relationships between patterns of dietary behaviours, identified by latent class analysis (LCA), and chronic uninvestigated dyspepsia (CUD). The present study was conducted to determine the association between the patterns of dietary behaviours, identified by LCA, and CUD in a large sample of adults. In a cross-sectional study conducted on 4763 Iranian adults, we assessed the patterns of dietary behaviours in four domains, including 'meal patterns', 'eating rate', 'intra-meal fluid intake' and 'meal-to-sleep interval', as identified by LCA, using a pre-tested comprehensive questionnaire. Patients with CUD were identified using the Rome III diagnostic criteria. CUD was prevalent in 15·2 % (95 % CI 14·4, 16·2 %; n 723) of patients. Early satiation occurred in 6·3 % (n 302) of patients, bothersome postprandial fullness in 8·0 % (n 384) of patients and epigastric pain in 7·8 % (n 371) of patients. We defined two distinct classes of meal patterns: 'regular' and 'irregular'. For eating rates, three classes were defined: 'moderate', 'moderate-to-slow' and 'moderate-to-fast'. Participants were identified as ingesting fluid with meals in two major classes: 'moderate intra-meal drinking' and 'high intra-meal drinking'. In terms of the interval between meals and sleeping, two distinct classes were identified: 'short meal-to-sleep interval' and 'long meal-to-sleep interval'. After controlling for potential confounders, the 'irregular meal pattern' was significantly associated with a greater odds of CUD (OR 1·42, 95 % CI 1·12, 1·78) compared with a 'regular meal pattern'. Individuals with a 'moderate-to-fast eating rate' were more likely to have CUD compared with those who had a 'moderate eating rate' (OR 1·42, 95 % CI 1·15, 1·75). Patterns of the 'meal-to-sleep interval' and 'intra-meal fluid intake' were not significantly associated with CUD. In conclusion, the 'irregular meal pattern' and the 'moderate-to-fast eating rate' were significantly associated with a greater odds of CUD. Further prospective investigations are warranted to confirm this association.

Treatment of functional dyspepsia and gastroparesis

OPINION STATEMENT

Functional dyspepsia (FD) and gastroparesis (GP) are the two most prevalent gastric neuromuscular disorders. These disorders are frequently confused, have more similarities than differences, and can be thought of as two ends of a continuous spectrum of gastric neuromuscular disorders (Fig. 1). FD is currently defined by the Rome III criteria; it is now subdivided into a pain-predominant subtype (epigastric pain syndrome) and a meal-associated subtype (post-prandial distress syndrome). GP is defined by symptoms in conjunction with delayed gastric emptying in the absence of mechanical obstruction. Symptoms for both FD and GP are similar and include epigastric pain or discomfort, early satiety, bloating, and post-prandial nausea. Vomiting can occur with either diagnosis; it is typically more common in GP. A patient suspected of having either FD or GP should undergo upper endoscopy. In suspected FD, upper endoscopy is required to exclude an alternative organic cause for the patient's symptoms; however, most (70 %) patients with dyspeptic symptoms will have FD rather than an organic disorder. In suspected GP, upper endoscopy is required to rule out a mechanical obstruction. A 4-hour solid-phase gastric emptying scan is recommended to confirm the diagnosis of GP; its utility is unclear in patients with FD, as it may not change treatment. Once the diagnosis of FD or GP is made, treatment should focus on the predominant symptom. This is especially true in patients with GP, as accelerating gastric emptying with the use of prokinetics may not necessarily translate into an improvement in symptoms. Unfortunately, no medication is currently approved for the treatment of FD and, thus, technically, all treatment options remain off-label, including medications for visceral pain (e.g., tricyclic antidepressants) and nausea. This review focuses on treatment options for FD and GP with an emphasis on new advances in the field over the last several years.

Digestive system dysfunction in cystic fibrosis: challenges for nutrition therapy

Cystic fibrosis can affect food digestion and nutrient absorption. The underlying mutation of the cystic fibrosis trans-membrane regulator gene depletes functional cystic fibrosis trans-membrane regulator on the surface of epithelial cells lining the digestive tract and associated organs, where Cl(-) secretion and subsequently secretion of water and other ions are impaired. This alters pH and dehydrates secretions that precipitate and obstruct the lumen, causing inflammation and the eventual degradation of the pancreas, liver, gallbladder and intestine. Associated conditions include exocrine pancreatic insufficiency, impaired bicarbonate and bile acid secretion and aberrant mucus formation, commonly leading to maldigestion and malabsorption, particularly of fat and fat-soluble vitamins. Pancreatic enzyme replacement therapy is used to address this insufficiency. The susceptibility of pancreatic lipase to acidic and enzymatic inactivation and decreased bile availability often impedes its efficacy. Brush border digestive enzyme activity and intestinal uptake of certain disaccharides and amino acids await clarification. Other complications that may contribute to maldigestion/malabsorption include small intestine bacterial overgrowth, enteric circular muscle dysfunction, abnormal intestinal mucus, and intestinal inflammation. However, there is some evidence that gastric digestive enzymes, colonic microflora, correction of fatty acid abnormalities using dietary n-3 polyunsaturated fatty acid supplementation and emerging intestinal biomarkers can complement nutrition management in cystic fibrosis.

Prevalence and risk factors of functional dyspepsia: a nationwide multicenter prospective study in Korea

GOALS

To evaluate the prevalence of functional dyspepsia (FD) and its risk factors.

BACKGROUND

FD is a common disorder, but its negative influences greatly affect the quality of life. The predictive factors of FD are still ambiguous.

STUDY

A total of 3399 participants underwent screening gastroscopy at one of 7 nationwide health care centers in Korea and who completed a questionnaire. Atrophic gastritis was defined by gastroscopy. Serologic Helicobacter pylori immunoglobulin G antibody was measured by enzyme-linked immunosorbent assay.

RESULTS

Of the 3399 participants who did not have organic diseases, 694 (20.4%) had dyspeptic symptoms such as epigastric pain/soreness or postprandial discomfort. Among the 694 participants, atrophic gastritis and positive H. pylori serology were found in 282 (40.6%) and 422 (60.8%), respectively; these proportions were not different from the remaining asymptomatic subjects. Multivariate analysis showed that having relatives with gastric cancer [odds ratio (OR), 1.35; 95% confidence interval (CI), 1.01-1.81], education below college (OR, 1.32; 95% CI, 1.06-1.64), and high-salt diet (OR, 1.33; 95% CI, 1.05-1.68) were associated with FD symptoms.

CONCLUSIONS

FD symptoms were frequently found in the health check-up subjects. Relatives of gastric cancer, education below college, and high-salt diet were risk factors of FD, suggesting that FD is a multifactorial disease.

Evidence-based approach to dyspepsia: from Helicobacter pylori to functional disease

Patients with dyspepsia may present with associated complaints of abdominal pain, bloating, fullness, acid reflux, and epigastric tenderness on examination. The evaluation of patients with dyspepsia includes taking a comprehensive history and performing a physical examination. Although taking a patient history has its limitations in making an accurate diagnosis, it is useful in guiding the selection of subsequent diagnostic tests. Differential diagnoses of dyspepsia are best addressed using an anatomical approach. Patients with chronic dyspepsia lasting > 1 month should be evaluated for the presence of alarm features. Alarm features mandate an upper gastrointestinal endoscopy examination, as these may be suggestive of a malignancy. In patients without alarm features, a Helicobacter pylori test-and-treat strategy is cost-effective if the prevalence of H. pylori infection is high. Tests for H. pylori infection can be divided into non-invasive and minimally invasive tests. Many different antibiotic combination therapies (eg, triple therapy, quadruple therapy, levofloxacin-based therapy, sequential therapy, concomitant therapy, and probiotics with eradication therapy) are now available for the eradication of H. pylori infection. In patients who are symptomatic without an organic pathology, functional dyspepsia and other causes of abdominal pain need to be considered. Functional dyspepsia is best managed using a multifaceted approach by establishing a good physician-patient relationship, dietary and lifestyle interventions, medical therapy, psychotherapy, and the use of psychotropic medications. This review rationalizes the current-day recommendations for the evaluation and management of patients with dyspepsia in a clinical setting.

Dietary fat intake and risk of pancreatic cancer in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial

PURPOSE

Epidemiologic and experimental studies suggest that dietary fat intake may affect risk of pancreatic cancer, but published results are inconsistent.

METHODS

We examined risk associations for specific types of dietary fat intakes and related food sources among 111,416 participants in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. We used Cox proportional hazards regression to examine associations between fat intake and pancreatic cancer risk.

RESULTS

Over a mean 8.4 years of follow-up, 411 pancreatic cancer cases were identified. We observed an inverse association between saturated fat intake and pancreatic cancer risk (hazard ratio [HR], 0.64 comparing extreme quintiles; 95% confidence interval [CI], 0.46-0.88), but the association became weaker and nonsignificant when individuals with fewer than 4 years of follow-up were excluded to avoid possible reverse causation (HR, 0.88; 95% CI, 0.58-1.33). Total fat intake showed a similar pattern of association, whereas intakes of monounsaturated and polyunsaturated fats and fats from animal or plant sources showed no associations with risk.

CONCLUSIONS

These results do not support the hypothesis of increased pancreatic cancer risk with higher fat consumption overall or by specific fat type or source. Dietary changes owing to undetected disease may explain the observed inverse association with saturated fat.

Fructose and lactose intolerance and malabsorption testing: the relationship with symptoms in functional gastrointestinal disorders

BACKGROUND

The association of fructose and lactose intolerance and malabsorption with the symptoms of different functional gastrointestinal disorders (FGID) remains unclear.

AIM

To investigate the prevalence of fructose and lactose intolerance (symptom induction) and malabsorption and their association with clinical gastrointestinal (GI) as well as non-GI symptoms in FGID and the outcome of dietary intervention.

METHODS

Fructose and lactose intolerance (defined by positive symptom index) and malabsorption (defined by increased hydrogen/methane) were determined in 1372 FGID patients in a single centre using breath testing. Results were correlated with clinical symptoms in different FGID Rome III subgroups. The effectiveness of a targeted saccharide-reduced diet was assessed after 6-8 weeks.

RESULTS

Intolerance prevalence across all FGIDs was 60% to fructose, 51% to lactose and 33% to both. Malabsorption occurred in 45%, 32% and 16% respectively. There were no differences in intolerance or malabsorption prevalence between FGID subgroups. FGID symptoms correlated with symptoms evoked during testing (r = 0.35-0.61. P < 0.0001), but not with malabsorption. Non-GI symptoms occurred more commonly in patients with intolerances. Methane breath levels were not associated with constipation using several cut-off thresholds. Adequate symptom relief was achieved in >80% of intolerant patients, irrespective of malabsorption.

CONCLUSIONS

Fructose and lactose intolerances are common in FGID and associated with increased non-GI symptoms, but not with specific FGID subtypes. Symptoms experienced during breath testing, but not malabsorption, correlate with FGID symptoms. Effective symptom relief with dietary adaptation is not associated with malabsorption. Mechanisms relating to the generation of GI and non-GI symptoms due to lactose and fructose in FGID need to be explored further.

Pathogenesis of functional dyspepsia

Functional dyspepsia (FD) is one of the most common clinical functional gastrointestinal disorders. As a chronic, relapsing and remitting disorder, FD not only significantly affects the quality of life of patients but also causes very high medical expenses. However, the specific pathogenesis of FD has always been a big problem for gastroenterologists. Recently, motility abnormalities, visceral hypersensitivity, psychosocial factors, Helicobacter pylori, genetic factors, excessive gastric acid secretion, environment, diet, and lifestyle have been proposed to explain the pathogenesis of FD, of which the brain-gut axis, autonomic nervous system , gastrointestinal hormones may play an important role. In this paper, we review the recent progress in the pathogenesis of FD.

Dietary and lifestyle factors in functional dyspepsia

Dietary factors are increasingly recognized to have an important role in triggering symptoms in a large proportion of patients with functional dyspepsia. Fatty foods seem to be the main culprits, but other foods (including carbohydrate-containing foods, milk and dairy products, citrus fruits, spicy foods, coffee and alcohol) have also been implicated. However, blind challenge tests do not provide consistent results. Moreover, although patients identify specific foods as triggers of their symptoms, these patients often do not seem to make behavioural adjustments in an attempt to improve symptoms; that is, any differences in dietary intake and lifestyle between patients and healthy individuals are small. Patients with functional dyspepsia exhibit mixed sensory-motor abnormalities, such as gastric hypersensitivity and impaired gastric accommodation of a meal. Nutrients, particularly fat, exacerbate these abnormalities and might thereby trigger postprandial symptoms. Cognitive factors, including anticipation related to previous negative experience with certain foods, might also have a role in triggering symptoms. Studies evaluating the potential beneficial effect of dietary interventions and changes in lifestyle are lacking, and this Review outlines a number of options that could be used as starting points for meaningful large-scale studies in the future.

Visceral and somatic sensory function in functional dyspepsia

BACKGROUND

Visceral hypersensitivity is one of the proposed underlying mechanisms in functional dyspepsia (FD). It is not clear whether visceral hypersensitivity in FD is a manifestation of a central sensitization also encompassing somatic sensitization. Transient receptor potential vanilloid-1 (TRPV(1)) pathways are involved in gastric mechanosensory physiology and the TRPV(1) receptor agonist, capsaicin, has been used as a chemical stimulant.

METHODS

In this double-blind, randomized study we evaluated both visceral and somatic sensory function in 34 FD patients and 42 healthy controls using quantitative sensory testing. Visceral pain sensitivity was assessed using a validated gastric pain model with oral capsaicin capsule titration and somatic pain sensitivity was determined by foot heat and hand electric stimulation.

KEY RESULTS

The median capsaicin dose required to attain moderate pain was 0.5mg in FD and 1mg in controls (P = 0.03). At these doses, mean pain intensities on a 0-100 visual analog scale were greater for FD than controls [56.9 (95% confidence intervals, 52.2-61.5) vs 45.1 (41.6-48.6), resp.] (P = 0.005). Overall, mean somatic sensory and pain thresholds were similar in FD and control groups, but in a subgroup of FD pain hypersensitivity was seen on the hand and on the foot at different stimulation thresholds.

CONCLUSIONS & INFERENCES

A majority of patients with FD have visceral chemo-hypersensitivity involving TRPV(1) pathways. A substantial subgroup also has somatic hypersensitivity as evidence of central sensitization.

Asian consensus report on functional dyspepsia

BACKGROUND AND AIM

Environmental factors such as food, lifestyle and prevalence of Helicobacter pylori infection are widely different in Asian countries compared with the West, and physiological functions and genetic factors of Asians may also be different from those of Westerners. Establishing an Asian consensus for functional dyspepsia is crucial in order to attract attention to such data from Asian countries, to articulate the experience and views of Asian experts, and to provide a relevant guide on management of functional dyspepsia for primary care physicians working in Asia.

METHODS

Consensus team members were selected from Asian experts and consensus development was carried out by using a modified Delphi method. Consensus teams collected published papers on functional dyspepsia especially from Asia and developed candidate consensus statements based on the generated clinical questions. At the first face-to-face meeting, each statement was reviewed and e-mail voting was done twice. At the second face-to-face meeting, final voting on each statement was done using a keypad voting system. A grade of evidence and strength of recommendation were applied to each statement according to the method of the GRADE Working Group.

RESULTS

Twenty-nine consensus statements were finalized, including seven for definition and diagnosis, five for epidemiology, nine for pathophysiology, and eight for management. Algorithms for diagnosis and management of functional dyspepsia were added.

CONCLUSIONS

  This consensus developed by Asian experts shows distinctive features of functional dyspepsia in Asia and will provide a guide to the diagnosis and management of functional dyspepsia for Asian primary care physicians.

Asian consensus report on functional dyspepsia

BACKGROUND/AIMS

Environmental factors such as food, lifestyle and prevalence of Helicobacter pylori infection are widely different in Asian countries compared to the West, and physiological functions and genetic factors of Asians may also be different from those of Westerners. Establishing an Asian consensus for functional dyspepsia is crucial in order to attract attention to such data from Asian countries, to articulate the experience and views of Asian experts, and to provide a relevant guide on management of functional dyspepsia for primary care physicians working in Asia.

METHODS

Consensus team members were selected from Asian experts and consensus development was carried out using a modified Delphi method. Consensus teams collected published papers on functional dyspepsia especially from Asia and developed candidate consensus statements based on the generated clinical questions. At the first face-to-face meeting, each statement was reviewed and e-mail voting was done twice. At the second face-to-face meeting, final voting on each statement was done using keypad voting system. A grade of evidence and a strength of recommendation were applied to each statement according to the method of the GRADE Working Group.

RESULTS

Twenty-nine consensus statements were finalized, including 7 for definition and diagnosis, 5 for epidemiology, 9 for pathophysiology and 8 for management. Algorithms for diagnosis and management of functional dyspepsia were added.

CONCLUSIONS

This consensus developed by Asian experts shows distinctive features of functional dyspepsia in Asia and will provide a guide to the diagnosis and management of functional dyspepsia for Asian primary care physicians.

Laboratory parameters and nutritional status in patients with functional dyspepsia

BACKGROUND

To investigate differences in laboratory markers, nutritional status parameters and eating patterns among newly diagnosed patients with functional dyspepsia.

METHOD

The investigation was performed on 180 newly diagnosed patients with functional dyspepsia, aged 20-79, which were referred to the gastroenterology unit of the Clinical and Hospital Center "Bezanijska Kosa" from April to October 2009. Rome II criteria were used for further classification.

RESULTS

ANOVA Bonferroni post hoc correction outlined that concentrations of serum magnesium and calcium were significantly lower in subjects with ulcer-like dyspepsia, while vitamin B12, glucose and immunoglobulin G level was significantly higher in group with dismotility-like dyspepsia. Statistical analysis revealed that the numbers of meal taken per day were significantly different. There was a statistical trend to skipping meals and to eat fast in patients with ulcer-like and dismotility-like functional dyspepsia when compared with non-specific dyspeptic subjects.

CONCLUSION

Patients with ulcer-like functional dyspepsia suffered from epigastric pain and burning and from heartburn, while persons with dismotility-like dyspepsia were complaining about postprandial fullness, bloating and early satiety. They skipped meals more frequently and avoided intake of certain supplies which, together with eating habits, provoked or emphasized the annoying symptoms.

Current understanding of pathogenesis of functional dyspepsia

Functional dyspepsia (FD) is a disorder in which upper abdominal symptoms occur in the absence of organic disease that explains them. Many pathogenic factors have been proposed for FD, including motility abnormalities, visceral hypersensitivity, psychosocial factors, excessive gastric acid secretion, Helicobacter pylori, genetics, environment, diet, lifestyle, and post-infectious FD. Many of those pathogenic factors are also common to irritable bowel syndrome and other functional gastrointestinal disorders, so understanding FD offers a glimpse into the nature of functional gastrointestinal disorders in general. Motility abnormalities and visceral hypersensitivity are thought to be important in the manifestation of FD symptoms, but the other factors are also thought to contribute by interacting and modifying motility and visceral hypersensitivity.

The speed of eating and functional dyspepsia in young women

BACKGROUND/AIMS

Little information is available on whether the speed of eating differs between individuals with and without dyspepsia, mainly because controlled studies are usually not feasible.

METHODS

A survey was applied to 89 individuals with relatively controlled eating patterns, using questionnaires that assessed eating time and functional dyspepsia (FD) based on the Rome III criteria.

RESULTS

The prevalence of FD was 12% (11 of 89 participants), and 7% (6 of 89) were diagnosed with gastroesophageal reflux disease (GERD). The proportion of individuals reporting that they ate their meals rapidly was higher for those with FD than for those without FD or GERD (control) (46% vs 17%, p=0.043), as was the reported eating speed (7.1+/-1.5 vs 5.8+/-2.0 [mean+/-SD], p=0.045; visual analog scale on which a higher score indicated faster eating). However, the measured eating time did not differ significantly between FD and controls (11.0+/-2.8 vs 12.8+/-3.3 minutes, p=0.098). The proportion of individuals who ate their meals within 13 minutes was significantly higher for those with FD than for controls (91% vs 51%, p=0.020).

CONCLUSIONS

The results of this study suggest that eating speed affects dyspepsia. Further studies are warranted.

Food intolerance, diet composition, and eating patterns in functional dyspepsia patients

The aims of this study are to investigate dietary factors, food intolerance, and the body mass index data, as an indicator of nutritional status, in functional dyspepsia patients. Forty-one functional dyspepsia patients and 30 healthy volunteers answered a standardized questionnaire to identify eating habits and food intolerance, and then completed a 7-day alimentary diary. There was no significant difference in daily total caloric intake between patients and controls. Patients associated their symptoms with the ingestion of several foods, but in general maintained their regular intake, with the exception of a small reduction in the proportion of fat in comparison with controls (median 28 vs. 34%; P = 0.001). No patient was underweight. In conclusion, our results suggest that food intolerance has no remarkable influence on food pattern and nutritional status in most functional dyspepsia patients. Further studies are necessary to clarify the role of fat in the generation of dyspeptic symptoms.

Whither dyspepsia? A historical perspective of functional dyspepsia, and concepts of pathogenesis and therapy in 2009

Functional dyspepsia is a highly prevalent but heterogeneous disorder; multiple pathogenetic mechanisms are likely involved but the underlying causal pathways in functional dyspepsia remain obscure. The term functional dyspepsia was popularized by the famed Walter Alvarez at the Mayo Clinic early last century. Prominent Australian gastroenterologists who have contributed to our understanding of functional dyspepsia include Peter Baume, Barry Marshall, Douglas Piper, Nick Talley, John Kellow, and Gerald Holtmann. Specific dyspeptic symptoms have not generally correlated very well with any particular physiologic disturbance, although gastric disaccommodation and duodenal eosinophilia have been linked to early satiety in this condition. Genetic markers have been tentatively identified, and functional dyspepsia can follow bacterial gastroenteritis. No objective diagnostic tools for functional dyspepsia are currently agreed upon, although meal induction of symptoms appears reproducible and may have diagnostic utility. The symptomatic criteria for functional dyspepsia (Rome III criteria) are based on expert consensus and the exclusion of organic causes. Various therapeutic modalities for functional dyspepsia have been explored; however, empirical approaches are still employed for the treatment of functional dyspepsia. Better approaches for functional dyspepsia are likely to follow an improved understanding of the underlying pathophysiological abnormalities.

Novel associations with dyspepsia: a community-based study of familial aggregation, sleep dysfunction and somatization

Dyspepsia is a common phenomenon and the majority of patients have functional dyspepsia; however, potential risk factors are unclear, with conflicting results in the literature. Although several risk factors have been evaluated previously, this knowledge has not led to more effective management of the disease. The aim of this study was to assess potential novel risk factors for dyspepsia in both a cross-sectional and a nested case-control study among a randomly selected community-based cohort. A valid questionnaire was mailed to a random sample of Olmsted County, MN residents (n = 659 responders; 133 had dyspepsia). In a nested case-control study, dyspeptic patients (n = 52) and healthy controls (n = 40) identified among community respondents completed further questionnaires on diet. Independent risk factors for dyspepsia adjusted for age, sex, body mass index and anti-secretory therapy were a positive family history of abdominal pain [odds ratio (OR) = 4.7, 95% confidence interval (CI) = 1.5-14.9, P = 0.008] and indigestion (OR = 3.4, 95% CI = 1.0-11.5, P = 0.048), difficulty falling asleep (OR = 8.2, 95% CI = 2.2-31.5, P = 0.002), poor sleep associated with worsening symptoms (OR = 15.9, 95% CI = 2.0-124.9, P = 0.009) and a high somatic symptom checklist score (OR = 5.6, 95% CI = 1.5-20.7, P = 0.01). Diet, including total calories (kcal day(-1)) and total protein, carbohydrate and fat intake (g day(-1)), was not significantly associated with dyspepsia. Familial aggregation raises the possibility of a genetic component, although environmental factors also need to be considered. Sleep dysfunction and somatization suggest a primary psychological component.

Effects of the phases of the menstrual cycle on gastric emptying, glycemia, plasma GLP-1 and insulin, and energy intake in healthy lean women

There is evidence that the menstrual cycle affects appetite, such that energy intake is lower during the follicular compared with the luteal phase. Gastric emptying influences energy intake, glycemia, and plasma glucagon-like peptide-1 (GLP-1), insulin, and cholecystokinin (CCK) release. We hypothesized that 1) gastric emptying of a glucose drink is slower, and glycemia, plasma hormones, hunger, and energy intake are less, during the follicular compared with the luteal phase; 2) the reduction in the latter parameters during the follicular phase are related to slower gastric emptying; and 3) these parameters are reproducible when assessed twice within a particular phase of the menstrual cycle. Nine healthy, lean women were studied on three separate occasions: twice during the follicular phase (days 6-12) and once during the luteal phase (days 18-24). Following consumption of a 300-ml glucose drink (0.17 g/ml), gastric emptying, blood glucose, plasma hormone concentrations, and hunger were measured for 90 min, after which energy intake at a buffet meal was quantified. During the follicular phase, gastric emptying was slower (P < 0.05), and blood glucose (P < 0.01), plasma GLP-1 and insulin (P < 0.05), hunger (P < 0.01), and energy intake (P < 0.05) were lower compared with the luteal phase, with no differences for CCK or between the two follicular phase visits. There were inverse relationships between energy intake, blood glucose, and plasma GLP-1 and insulin concentrations with the amount of glucose drink remaining in the stomach at t = 90 min (r < -0.6, P < 0.05). In conclusion, in healthy women 1) gastric emptying of glucose is slower, and glycemia, plasma GLP-1 and insulin, hunger, and energy intake are less during the follicular compared with the luteal phase; 2) energy intake, glycemia, and plasma GLP-1 and insulin are related to gastric emptying; and 3) these parameters are reproducible when assessed twice during the follicular phase.

Gastric emptying of liquid and solid meals at various temperatures: effect of meal temperature for gastric emptying

BACKGROUND

Patients with functional dyspepsia frequently show delayed gastric emptying, and dietary advice is frequently given for its improvement. If meal temperature influences gastric emptying, advice regarding the meal temperature may become a possible component of dietary therapy. However, little information exists concerning the thermal effect of meals on gastric emptying. The aim of this study was to determine the thermal effect of liquid and solid meals on gastric emptying.

METHODS

The gastric emptying of liquid and solid test meals was examined in healthy volunteers (liquid, n = 25, mean age = 35.7 +/- 9.6 years, male-to-female ratio = 22:3; solid, n = 25, mean age = 35.2 +/- 8.8 years, male-to-female ratio = 20:5). Gastric emptying after the ingestion of liquid or solid meals at three different temperatures (4, 37, and 60 degrees C) was investigated with the [(13)C]-labeled acetate breath test. The lag phase time (T (max-calc)) and the half-emptying time (T (1/2)) were calculated from the (13)CO(2) breath excretion curve as indices of gastric emptying.

RESULTS

The values of T (max-calc) at 60 degrees C with both the liquid and solid meals were significantly smaller than those at 37 degrees C (P < 0.05). However, there was no difference in the T (1/2) values. In the analysis of the percent excretion of (13)CO(2) in 1 h (% dose/h) data with the liquid meal test in the earlier phase within 30 min, significantly larger values were found at 60 degrees C than at the other temperatures. These findings suggest that a hot meal significantly accelerates gastric emptying.

CONCLUSIONS

Meal temperature may be considered as a component of dietary therapy for patients with functional dyspepsia.

Reproducibility of energy intake, gastric emptying, blood glucose, plasma insulin and cholecystokinin responses in healthy young males

Gastric emptying, as well as intragastric meal distribution, and gastrointestinal hormones, including cholecystokinin (CCK), play an important role in appetite regulation. The evaluation of gastrointestinal factors regulating food intake is commonly performed in healthy, lean, young male participants. It has, however, been suggested that there is a marked interindividual variability in the effects of nutrient 'preloads' on energy intake in this group. Whether there is significant intraindividual variation in acute energy intake after a nutrient preload, and, if so, how this relates to day-to-day differences in gastric emptying and gastrointestinal hormone release, is unclear. The purpose of the present paper is to evaluate the hypothesis that energy intake after a nutrient preload would be reproducible and associated with reproducible patterns of gastric emptying, intragastric distribution and gastrointestinal hormone release. Fifteen healthy men (age 25 (sem 5) years) consumed a glucose preload (50 g glucose in 300 ml water; 815 kJ) on three occasions. Gastric emptying and intragastric meal distribution (using three-dimensional ultrasound), blood glucose, plasma insulin and CCK concentrations and appetite perceptions were evaluated over 90 min, and energy intake from a cold buffet-style meal was then quantified. Energy intake was highly reproducible within individuals between visits (intraclass correlation coefficient, ri = 0.9). Gastric emptying, intragastric meal distribution, blood glucose, plasma insulin and CCK concentrations and appetite perceptions did not differ between visits (ri>0.7 for all). In healthy males, energy intake is highly reproducible, at least in the short term, and is associated with reproducible patterns of gastric emptying, glycaemia, insulinaemia and CCK release.

Plasma glucagon-like peptide 1 and peptide YY levels are not altered in symptomatic fructose-sorbitol malabsorption

OBJECTIVE

Carbohydrate malabsorption causes more symptoms in patients with functional gastrointestinal disorders than in healthy individuals. The purpose of this study was to investigate whether this could be explained by differences in ileal brake hormone secretion.

MATERIAL AND METHODS

Eighteen consecutive patients with functional abdominal complaints, referred to our clinic for investigation of self-reported food hypersensitivity, were included in the study and compared with 15 healthy volunteers. All subjects ingested a mixture of 25 g fructose and 5 g sorbitol. Pulmonary hydrogen and methane excretion and plasma glucagon-like peptide 1 (GLP-1) and peptide YY (PYY) levels were measured during the next 3 h. Both habitual and post-test symptoms were assessed.

RESULTS

Malabsorption of fructose and sorbitol was present in 61% of the patients and 73% of the controls. Nevertheless, the patients experienced significantly more symptoms following carbohydrate challenge, and 78% of the patients claimed that the challenge replicated their habitual gastrointestinal complaints. No significant differences in gas excretion or GLP-1 and PYY levels were found between patients and controls or between symptomatic and asymptomatic carbohydrate malabsorbers. A weak correlation between hydrogen excretion and PYY levels was demonstrated in non-producers of methane.

CONCLUSIONS

Neither intestinal gas production nor ileal brake hormone secretion seems to play a role in the symptomatology of carbohydrate intolerance in patients with self-reported food hypersensitivity. Other mechanisms related to bacterial fermentation may be involved and should be investigated further.

Urocortins and cholecystokinin-8 act synergistically to increase satiation in lean but not obese mice: involvement of corticotropin-releasing factor receptor-2 pathway

Interactions between gastrointestinal signals are a part of integrated systems regulating food intake (FI). We investigated whether cholecystokinin (CCK)-8 and urocortin systems potentiate each other to inhibit FI and gastric emptying (GE) in fasted mice. Urocortin 1 and urocortin 2 (1 microg/kg) were injected ip alone or with CCK (3 microg/kg) in lean, diet-induced obese (DIO) or corticotropin-releasing factor receptor-2 (CRF(2))-deficient mice. Gastric vagal afferent activity was recorded from a rat stomach-vagus in vitro preparation. When injected separately, urocortin 1, urocortin 2, or CCK did not modify the 4-h cumulative FI in lean mice. However, CCK plus urocortin 1 or CCK plus urocortin 2 decreased significantly the 4-h FI by 39 and 27%, respectively, compared with the vehicle + vehicle group in lean mice but not in DIO mice. Likewise, CCK-urocortin-1 delayed GE in lean but not DIO mice, whereas either peptide injected alone at the same dose had no effect. CCK-urocortin 2 suppression of FI was observed in wild-type but not CRF(2)-deficient mice. Gastric vagal afferent activity was increased by intragastric artery injection of urocortin 2 after CCK at a subthreshold dose, and the response was reversed by devazepide. These data establish a peripheral synergistic interaction between CCK and urocortin 1 or urocortin 2 to suppress FI and GE through CRF(2) receptor in lean mice that may involve CCK modulation of gastric vagal afferent responsiveness to urocortin 2. Such synergy is lost in DIO mice, suggesting a resistance to the satiety signaling that may contribute to maintain obesity.

Appetite and obesity: a gastroenterologist's perspective

This review focuses on the gastrointestinal tract's control of appetite and interventions directed to the gut that are effective in the treatment of obesity. It examines the evidence linking gut hormones to the control of both appetite and upper gastrointestinal motility, the evidence that stomach function is altered and contributes to satiation in obesity and outlines the principles of therapy for obesity which are directed at the gastrointestinal tract. These therapies impair fat absorption or alter stomach functions through pharmacological, device, endoscopic, or surgical approaches. Gastroenterologists need to understand the role of factors controlling appetite in order to effectively manage the increasing number of obese patients and the ways the gut function may be altered as a result of the treatments and their complications.

Relationship of functional gastrointestinal disorders and psychiatric disorders: Implications for treatment

This article revisits the links between psychopathology and functional gastrointestinal disorders such as irritable bowel syndrome (IBS), discusses the rational use of antidepressants as well as non-pharmacological approaches to the management of IBS, and suggests guidelines for the treatment of IBS based on an interdisciplinary perspective from the present state of knowledge. Relevant published literature on psychiatric disorders, especially somatization disorder, in the context of IBS, and literature providing direction for management is reviewed, and new directions are provided from findings in the literature. IBS is a heterogeneous syndrome with various potential mechanisms responsible for its clinical presentations. IBS is typically complicated with psychiatric issues, unexplained symptoms, and functional syndromes in other organ systems. Most IBS patients have multiple complaints without demonstrated cause, and that these symptoms can involve systems other than the intestine, e.g. bones and joints (fibromyalgia, temporomandibular joint syndrome), heart (non-cardiac chest pain), vascular (post-menopausal syndrome), and brain (anxiety, depression). Most IBS patients do not have psychiatric illness per se, but a range of psychoform (psychological complaints in the absence of psychiatric disorder) symptoms that accompany their somatoform (physical symptoms in the absence of medical disorder) complaints. It is not correct to label IBS patients as psychiatric patients (except those more difficult patients with true somatization disorder). One mode of treatment is unlikely to be universally effective or to resolve most symptoms. The techniques of psychotherapy or cognitive-behavioral therapy can allow IBS patients to cope more readily with their illness. Specific episodes of depressive or anxiety disorders can be managed as appropriate for those conditions. Medications designed to improve anxiety or depression are not uniformly useful for psychiatric complaints in IBS, because the psychoform symptoms that sound similar to those seen in psychiatric disorders may not have the same significance in patients with IBS.