Acacia fiber or probiotic supplements to relieve gastrointestinal complaints in patients with constipation-predominant IBS: a 4-week randomized double-blinded placebo-controlled intervention trial.

PURPOSE: To date, no adequate treatment for irritable bowel syndrome with predominant constipation complaints (IBS-C) is available. Fibers with prebiotic properties and probiotic compounds have shown promise in relieving IBS-C-related complaints. We aimed to determine the effects of a 4-week intervention with either an Acacia fiber (AF) with prebiotic properties or a probiotic Bifidobacterium Lactis (BLa80) supplement, compared to a control supplement, on stool pattern, IBS symptoms and Quality of Life (QoL), in IBS-C individuals. METHODS: A parallel, double-blind, randomized controlled trial involving 180 subjects meeting the ROME IV criteria for IBS-C was conducted. Following a 4-week observation period, subjects received either AF (10 g), Probiotic BLa80 (4 g; 2 × 1011 CFU/g) or a maltodextrin placebo (10 g) daily for 4 weeks. Subjects reported daily information on stool pattern and gastrointestinal complaints. Before and after each 4-week period, questionnaires on symptom severity, constipation symptoms, anxiety and depression and QoL were completed. Stool mass was measured for 5-days before and after the intervention. RESULTS: Stool frequency significantly improved in the AF and Probiotic BLa80 groups compared to placebo (P < 0.001, P = 0.02, respectively). Probiotic BLa80 showed a significant reduction in IBS symptom severity (P = 0.03), for AF a trend towards decreased constipation symptoms (PAC-SYM, P = 0.10) was observed. No significant changes in stool consistency, stool mass or QoL measures were observed between the AF and Probiotic BLa80 compared to placebo. CONCLUSION: Daily dietary supplementation with Acacia fiber and probiotic supplements might help IBS-C patients by relieving IBS-related complaints compared to a placebo supplement. REGISTRATION NUMBER OF CLINICAL TRIAL: The trial is registered at ClinicalTrials.gov: NCT04798417: Study Details | Nutrition to Relieve IBS Constipation | ClinicalTrials.gov.

Fecal Microbiota Signatures Are Not Consistently Related to Symptom Severity in Irritable Bowel Syndrome.

BACKGROUND: Irritable bowel syndrome (IBS) is the most prevalent functional bowel disorder, but its pathophysiology is still unknown. Although a microbial signature associated with IBS severity has been suggested, its association with IBS severity still remains largely unknown. AIMS: This study aims to assess longitudinal dynamics of fecal microbiota and short-chain fatty acids (SCFAs) in different IBS severity groups and study the association with stool pattern, diet, depression, anxiety, and quality of life (QoL). METHODS: A longitudinal study was performed, including n = 91 IBS patients and n = 28 matched controls. All participants collected fecal samples for microbiota composition and SCFA analysis and completed validated questionnaires regarding IBS severity, stool pattern, depression, anxiety, and IBS-QoL at two timepoints with four weeks in-between. Diet was assessed at the first timepoint. RESULTS: Over time, 36% of IBS patients changed in severity group, and 53% changed in predominant stool pattern. The largest proportion of microbiota variation was explained by the individual (R2 = 70.07%). Microbiota alpha diversity and composition, and SCFAs did not differ between IBS severity groups, nor between IBS and controls. Relative abundances of Bifidobacterium, Terrisporobacter, and Turicibacter consistently differed between IBS and controls, but not between IBS severity groups. Large dynamics over time were observed in the association of microbiota composition with questionnaire data where IBS symptom severity was associated at T1 but not at T2. CONCLUSIONS: Fecal microbiota and SCFA signatures were not consistently associated with IBS severity over time, indicating the importance of repeated sampling in IBS research.

Increasing dietary fibre intake in healthy adults using personalised dietary advice compared with general advice: a single-blind randomised controlled trial.

OBJECTIVE: A high-fibre diet is associated with a lower risk for diseases. However, few adults meet the dietary fibre recommendation. Therefore, the effects and acceptance of an algorithm-generated personalised dietary advice (PDA) compared with general advice (GA) on fibre intake were investigated. DESIGN: A 6-week, single-blind randomised controlled trial with a 3-month follow-up. SETTING: PDA was based on habitual intake and provided fibre-rich alternatives using a website; GA contained brochures. Dietary intake was assessed at baseline, week 1, week 6 and 3-month follow-up. Both groups evaluated their advice at week 6. All participants had access to PDA from week 7 until 3-month follow-up. PARTICIPANTS: Two groups of healthy adults: PDA (n 34) and GA (n 47). For 3-month follow-up analysis, participants were re-divided into visitors (n 52) and non-visitors (n 26) of the PDA. RESULTS: At week 6, energy intake remained stable in both groups, but fibre intake per 1000 kcal increased non-significantly in both groups (PDA = Δ0·5 ± 2·8; GA = Δ0·8 ± 3·1, P = 0·128). Importantly, a significantly higher percentage of PDA participants adhered to the recommendation compared with week 1 (PDA = 21 % increase; GA = 4 % increase, P ≤ 0·001). PDA participants evaluated the advice significantly better compared with GA participants. At 3-month follow-up, fibre intake increased compared with baseline (visitors = Δ2·2 ± 2·6, P < 0·001; non-visitors = Δ1·5 ± 1·9, P = 0·001), but was insignificantly different between groups. Visitors had a decrease and non-visitors had an increase in energy intake (visitors =Δ - 132 ± 525; non-visitors = Δ109 ± 507, P = 0·055). CONCLUSIONS: The algorithm-generated PDA was well accepted and stimulated adherence to the recommendations more than GA, indicating to be a suitable and cost-efficient method for improving dietary fibre intake in healthy adults.

Development and validation of the FiberScreen: A short questionnaire to screen fibre intake in adults.

BACKGROUND: Health effects of dietary fibres are the topic of many studies. Eligibility criteria often include a certain fibre intake, which requires dietary screening during recruitment. However, dietary assessment methods are extensive and burdensome for both the researcher and participant. Therefore, we developed and validated a short questionnaire (FiberScreen) to screen fibre intake. METHODS: The initial five-item questionnaire assessed fruit, vegetable, whole grain, pasta/rice/potato and legume intake. The optimised FiberScreen included 18 items, which further specified intake of the above-mentioned categories, and included nuts and seeds. The FiberScreen was completed during two fibre promoting interventions. In Study A, participants without constipation completed the five-item FiberScreen and a food frequency questionnaire (FFQ) during screening (n = 131), and the 18-item FiberScreen and a FFQ at 3-month follow-up (n = 87). In Study B, 29 constipated participants completed the 18-item FiberScreen at screening and a FFQ during the first study visit. RESULTS: The fibre estimate from the five-item FiberScreen and the FFQ was moderately correlated (r = 0.356, p < 0.001). Importantly, the 18-item FiberScreen and FFQ, when data of both studies were combined, had a strong correlation (r = 0.563, p < 0.001). The 18-item FiberScreen had a lower fibre estimate compared to the FFQ (Δ = 1.2 ± 5.9 g, p = 0.030) but the difference was relatively small. Bland-Altman plots showed a good agreement between the questionnaires. Completion time of the 18-item FiberScreen was 4.2 ± 2 min. CONCLUSIONS: The 18-item FiberScreen is a suitable short screening questionnaire for ranking the fibre intake of adults. The 18-item FiberScreen can help to reduce screening burden for both the participant and researcher.

Impaired intestinal function is associated with lower muscle and cognitive health and well-being in patients with congestive heart failure.

BACKGROUND: Small- and large-intestinal perturbations have been described as prevalent extracardiac systemic manifestations in congestive heart failure (CHF), but alterations in protein digestion and absorption and plasma short-chain fatty acid (SCFA) concentrations and the potential link with other systemic effects (muscle and cognitive health) have not been investigated in CHF. METHODS: We analyzed protein digestion and absorption with dual stable tracer method in 14 clinically stable, noncachectic CHF outpatients (mean left ventricular ejection fraction: 35.5% [95% CI, 30.9%-40.1%]) and 15 controls. Small-intestinal non-carrier-mediated permeability and active carrier-mediated glucose transport were quantified by sugar permeability test. Plasma SCFA (acetate, propionate, butyrate, isovalerate, valerate) concentrations were measured as intestinal microbial metabolites. Muscle function was assessed by isokinetic dynamometry, cognition by a battery of tests, and well-being by questionnaire. RESULTS: Protein digestion and absorption were impaired by 29.2% (P = .001) and active glucose transport by 38.4% (P = .010) in CHF. Non-carrier-mediated permeability was not altered. Whereas plasma propionate, butyrate, and isovalerate concentrations were lower in CHF (P < .05), acetate and valerate concentrations did not differ. Overall, intestinal dysfunction was associated with impaired leg muscle quality, emotional distress, and cognitive dysfunction (P < .05). CONCLUSIONS: We identified impaired protein digestion and absorption and altered SCFA concentrations as additional intestinal dysfunctions in CHF that are linked to reduced muscle and cognitive health and well-being. More research is needed to implement strategies to improve intestinal function in CHF and to investigate the mechanisms underlying its link with other systemic manifestations.

Methanogen Levels Are Significantly Associated with Fecal Microbiota Composition and Alpha Diversity in Healthy Adults and Irritable Bowel Syndrome Patients.

Hydrogenotrophic microbes, primarily including the three functional groups methanogens, sulfate-reducing bacteria, and reductive acetogens, use hydrogen as an energy source and play an important role in maintaining the hydrogen balance in gut ecosystems. A distorted hydrogen balance has been associated with irritable bowel syndrome (IBS). However, the role of hydrogenotrophic microbes in overall microbiota composition and function remains largely unknown. This study aims to assess the distribution and stability of hydrogenotrophic functional groups in healthy adults (HAs) and IBS patients and their association with overall microbiota composition and IBS symptoms. A two-time-point study with 4 weeks in between was performed with 27 HAs and 55 IBS patients included. Our observations revealed that methanogens showed a bimodal distribution across samples. A high-level methanogen microbiota was consistently associated with higher alpha diversity, and its composition was significantly different from that of individuals with a low-level methanogen microbiota. In general, these associations were more pronounced in IBS patients than in HAs. The differences in the copy numbers of genes indicative of total bacteria and acetogens between HAs and IBS patients and their correlations with IBS symptom severity, anxiety, depression, and quality of life (QoL) were sampling time dependent. Hydrogenotrophic functional groups did not show negative abundance correlations with each other in HAs and IBS patients. These findings suggest that methanogen levels in the gut have a pronounced association with microbiota alpha diversity and composition, and the interactions between hydrogenotrophic functional groups are complex in gut ecosystems. IMPORTANCE Hydrogenotrophic microbes play an essential role in the disposal of hydrogen and the maintenance of the hydrogen balance in gut ecosystems. Their abundances vary between individuals and have been reported to be associated with human gut disorders such as irritable bowel disease. This study confirms that methanogen levels show a bimodal distribution. Moreover, a high-level methanogen microbiota was associated with higher alpha diversity, and its composition was different from that of individuals with a low-level methanogen microbiota. These associations are more pronounced in IBS patients than in healthy subjects. In addition, associations between hydrogenotrophic microbes and IBS symptom scores vary over time, which argues for the use of longitudinal study designs. Last but not least, this study suggests that the different hydrogenotrophic microbes coexist with each other and do not necessarily compete for hydrogen in the gut. The findings in this study highlight the impact of methanogens on overall microbiota composition and function.

A high-fibre personalised dietary advice given via a web tool reduces constipation complaints in adults.

Constipation can greatly impact the quality of life (QoL), which can be relieved by dietary fibres; however, preserving a higher fibre intake remains a challenge. We investigated the effects of a personalised dietary advice (PDA) on fibre intake and mild constipation complaints. A total number of twenty-five adults with mild constipation complaints were included in a 4-week observation period followed by a 4-week personalised intervention. The PDA provided high-fibre alternatives via a web tool. In weeks 1, 4 and 8, dietary intake, constipation complaints and QoL were assessed. Furthermore, participants collected a faecal sample at weeks 1, 4 and 8 to determine microbiota diversity and composition, and short-chain fatty acids (SCFA). Participants completed questions daily for 8 weeks regarding abdominal complaints, stool frequency and stool consistency. Fibre intake in week 8 was significantly higher compared to week 1 (Δ = 5·7 ± 6·7 g, P < 0·001) and week 4 (Δ = 5·2 ± 6·4 g, P < 0·001). Constipation severity and QoL significantly improved at week 8 compared to the observation period (P < 0·001). A higher fibre intake significantly reduced constipation severity (ß = -0·031 (-0·05; -0·01), P = 0·001) and the QoL (ß = -0·022 (-0·04; -0·01), P = 0·009). Stool consistency (P = 0·040) and abdominal pain (P = 0·030) improved significantly during the intervention period (P = 0·040), but stool frequency did not. Average microbial alpha diversity and composition and SCFA concentrations did not change over time, but indicated individual-specific dynamics. Several SCFAs were associated with constipation complaints. To conclude, a PDA effectively increased fibre intake and subsequently reduced constipation complaints, indicating that guided dietary adjustments are important and feasible in the treatment of mild constipation complaints.

Subtypes and Severity of Irritable Bowel Syndrome Are Not Related to Patients' Self-Reported Dietary Triggers: Results From an Online Survey in Dutch Adults.

BACKGROUND: Diet plays an important role in symptom management of irritable bowel syndrome (IBS). However, current diet therapies are not optimal nor successful for everyone. OBJECTIVE: To investigate whether subgroups based on IBS subtypes or severity identify different self-reported dietary triggers, and whether these are associated with severity and psychological factors. DESIGN: Online cross-sectional survey PARTICIPANTS: Patients with IBS (n = 1601) who fulfilled the Rome IV criteria or had an IBS diagnosis. MAIN OUTCOMES: Self-reported response to 44 preselected dietary triggers, IBS quality of life, and anxiety and depression. Subgroups were based on subtypes or severity. STATISTICAL ANALYSIS: Response to dietary triggers was analyzed using multiple correspondence analysis. Moreover, a food score was calculated to quantify the number and severity of responses to dietary triggers. RESULTS: Response to greasy foods, onions, cabbage, and spicy and fried foods were mentioned most often (ranging between 55% and 65%). Response to dietary triggers differed between subtypes and severity groups, but absolute differences were small. Multiple correspondence analysis did not reveal clustering between dietary triggers, and ellipses for the subtypes overlapped. Some clustering was seen when ellipses were drawn for severity, which indicates that severity explained a fraction of the variation in response to dietary triggers, and subtypes did not. The food score was not significantly different between subtypes but was significantly higher with higher levels of severity (mild = 20.9 ± 17, moderate = 29.2 ± 19, severe = 37.9 ± 20, P < .001), having depressive (no = 31.4 ± 20, yes = 37.4 ± 20, P < .001) or anxious symptoms (no = 30.7 ± 20, yes = 35.2 ± 20, P < .001), and lower quality of life (lower quality of life = 38.5 ± 19, higher quality of life = 26.5 ± 19, P < .001). CONCLUSION: Patients with different IBS subtypes or IBS severity do not identify different self-reported dietary triggers. Patients with more severe IBS and who experience anxiety or depression tend to have severe responses to more dietary triggers. IBS severity seems a better classifier than Rome IV criteria regarding diet. Dietary treatment needs to be individualized under guidance of a dietitian.

Effect of carbohydrate restriction in patients with hyperinsulinemic hypoglycemia after Roux-en-Y gastric bypass.

BACKGROUND: Hyperinsulinemic hypoglycemia is a rare complication of Roux-en-Y gastric bypass (RYGB) surgery. Meals with a high carbohydrate (carb) content and high glycemic index (GI) may provoke these hypoglycemic attacks. The aim of this study is to assess the effects of reducing meal carb content and GI on glycemic responses in patients with post-RYGB hypoglycemia. METHODS: Fourteen patients with post-RYGB hypoglycemia underwent two meal tests: a mixed meal test (MMT) with a carb content of 30 g and a meal test with the low GI supplement, Glucerna SR 1.5® (Glucerna meal test (GMT)). Plasma glucose and serum insulin levels were measured for a period of 6 h. RESULTS: Peak glucose levels were reached at T 30 during GMT and at T 60 during MMT, and they were 1.5 ± 0.3 mmol/L lower during GMT than during MMT (7.5 ± 0.4 vs 9.0 ± 0.4 mmol/L, P < 0.005). GMT induced the most rapid rise in plasma insulin: at T 30 plasma, insulin was 30.7 ± 8.5 mU/L higher during GMT than during MMT (P < 0.005). None of the carb-restricted meals induced post-prandial hypoglycemia. CONCLUSION: A 30-g carb-restricted meal may help to prevent post-prandial hypoglycemia in patients with post-RYGB hypoglycemia. The use of a liquid, low GI, supplement offers no additional advantage.