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.

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.

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.

 

Dietary screening during recruitment is more elaborate than is often needed, and burdensome for both the researcher and participant.

An 18‐item FiberScreen questionnaire to screen fibre intake was developed and validated in Dutch adults with and without gastrointestinal complaints.

The 18‐item FiberScreen had a good agreement with a food frequency questionnaire.

Completion time of the 18‐item FiberScreen was around 4 min, compared to 45–60 min for the food frequency questionnaire.

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.

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.

Impairments in Protein Digestion and Absorption Attenuate the Anabolic Response to Feeding in Patients with Congestive Heart Failure (FS09-03-19)

Objectives

Gastrointestinal symptoms are prevalent extracardiac systemic manifestations of Congestive Heart Failure (CHF). We developed a comprehensive panel of methods to unravel gut dysfunction in CHF and its impact on the anabolic response to feeding.

Methods

We recruited 14 clinically stable CHF patients (ejection fraction: 33.9 ± 2.1, NYHA class: 2.3 ± 0.2) and 17 healthy controls matched for age and gender. Stable tracers of L-phenylalanine (PHE)-[ring-2H5] and L-tyrosine (TYR)-[13C9,15 N] were administered intravenously for 5 hours via primed constant and continuous infusion. After 2 hours, participants ingested a complete high protein meal containing L-PHE-[1–13C] and spirulina-[U-15 N]. We sampled blood throughout the study to analyze enrichments by LC-MS/MS. We calculated the anabolic response to feeding before and after correction for changes in protein digestion and absorption, assessed by spirulina degradation ratio (L-PHE-[15 N]/[1–13C]). Moreover, we measured small intestinal membrane integrity and active carrier-mediated glucose transport by urinary recovery of the orally ingested inert sugars lactulose, rhamnose, and 3-O-methyl-glucose. Disease severity was assessed by medical chart and history. Statistical analysis was performed by unpaired t-tests. Data are expressed as mean ± SEM.

Results

In CHF patients, protein digestion and absorption were reduced (0.66 ± 0.04 vs. 0.82 ± 0.04, P < 0.01), which further attenuated the anabolic response to feeding (28.3 ± 3.8 vs. 54.0 ±5.5 μmol/kg FFM/meal, P < 0.001). Disturbances in protein digestion and absorption as well as anabolic response in CHF were independent of disease severity. Small intestinal permeability and active carrier-mediated glucose transport did not differ between the groups indicating a preserved enterocyte function in CHF patients.

Conclusions

We hypothesize that enhancing protein digestion and absorption in patients with CHF can improve the availability of nutrients and protein anabolism.

Funding Sources

National Institutes of Health

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.