Clinical trial: A Mediterranean diet is feasible and improves gastrointestinal and psychological symptoms in irritable bowel syndrome

BACKGROUND

Diet is fundamental to the care of irritable bowel syndrome (IBS). However, some approaches are not appropriate for individuals experiencing psychological symptoms.

AIMS

To assess feasibility of a Mediterranean diet in IBS and its impact on gastrointestinal and psychological symptoms.

METHODS

We recruited adults with Rome IV IBS and mild or moderate anxiety and/or depressive symptoms to an unblinded 6-week randomised controlled trial. Patients were randomised to Mediterranean diet counselling or habitual diet. We collected gastrointestinal and psychological symptom data, dietary data and stool samples for metagenomic sequencing.

RESULTS

We randomised 59 individuals (29 Mediterranean diet, 30 control); 48 completed the study. The Mediterranean Diet Adherence Screener score was higher in the Mediterranean diet group than controls at week 6 (7.5 [95% CI: 6.9-8.0] vs. 5.7 [5.2-6.3], p < 0.001), and there was a greater score increase than controls (2.1 [95% CI: 1.3-2.9] vs. 0.5 [95% CI: 0.1-1.0], p = 0.004), demonstrating Mediterranean diet feasibility. There was a greater proportion of gastrointestinal symptom responders in the Mediterranean diet group than controls (24/29, 83% vs. 11/30, 37%, p < 0.001) and depression responders (15/29, 52% vs. 6/30 20%, p = 0.015). There was no difference in FODMAP intake at week 6 (p = 0.51). Gastrointestinal adverse events were similar (p = 0.588). There were no differences in change in microbiome parameters between groups.

CONCLUSIONS

A Mediterranean diet is feasible in IBS and leads to improvement in gastrointestinal and psychological symptoms. Although this study was unblinded, these findings together with the broader benefits of the Mediterranean diet, provide strong impetus for future research in IBS. Australia New Zealand Clinical Trials Registry: ACTRN12620001362987.

Ten-year territory-wide trends in the utilisation and clinical outcomes of extracorporeal membrane oxygenation in Hong Kong

INTRODUCTION

The utilisation of extracorporeal membrane oxygenation (ECMO) has been rapidly increasing in Hong Kong. This study examined 10-year trends in the utilisation and clinical outcomes of ECMO in Hong Kong.

METHODS

We retrospectively reviewed the records of all adult patients receiving ECMO who were admitted to the intensive care units (ICUs) of public hospitals in Hong Kong between 2010 and 2019. Temporal trends across years were assessed using the Mann-Kendall test. Observed hospital mortality was compared with the Acute Physiology and Chronic Health Evaluation (APACHE) IV-predicted mortality.

RESULTS

The annual number of patients receiving ECMO increased from 18 to 171 over 10 years. In total, 911 patients received ECMO during the study period: 297 (32.6%) received veno-arterial ECMO, 450 (49.4%) received veno-venous ECMO, and 164 (18.0%) received extracorporeal cardiopulmonary resuscitation. The annual number of patients aged ≥65 years increased from 0 to 47 (27.5%) [P for trend=0.001]. The median (interquartile range) Charlson Comorbidity Index increased from 1 (0-1) to 2 (1-3) [P for trend<0.001] while the median (interquartile range) APACHE IV score increased from 90 (57-112) to 105 (77-137) [P for trend=0.003]. The overall standardised mortality ratio comparing hospital mortality with APACHE IV-predicted mortality was 1.11 (95% confidence interval=1.01-1.22). Hospital and ICU length of stay both significantly decreased (P for trend=0.011 and <0.001, respectively).

CONCLUSION

As ECMO utilisation increased in Hong Kong, patients put on ECMO were older, more critically ill, and had more co-morbidities. It is important to combine service expansion with adequate resource allocation and training to maintain quality of care.

Fiber intake and fiber intervention in depression and anxiety: a systematic review and meta-analysis of observational studies and randomized controlled trials

CONTEXT

Dietary fibers hold potential to influence depressive and anxiety outcomes by modulating the microbiota-gut-brain axis, which is increasingly recognized as an underlying factor in mental health maintenance.

OBJECTIVE

Evidence for the effects of fibers on depressive and anxiety outcomes remains unclear. To this end, a systematic literature review and a meta-analysis were conducted that included observational studies and randomized controlled trials (RCTs).

DATA SOURCES

The PubMed, Embase, CENTRAL, CINAHL, and PsychINFO databases were searched for eligible studies.

DATA EXTRACTION

Study screening and risk-of-bias assessment were conducted by 2 independent reviewers.

DATA ANALYSIS

Meta-analyses via random effects models were performed to examine the (1) association between fiber intake and depressive and anxiety outcomes in observational studies, and (2) effect of fiber intervention on depressive and anxiety outcomes compared with placebo in RCTs. A total of 181 405 participants were included in 23 observational studies. In cross-sectional studies, an inverse association was observed between fiber intake and depressive (Cohen's d effect size [d]: -0.11; 95% confidence interval [CI]: -0.16, -0.05) and anxiety (d = -0.25; 95%CI, -0.38, -0.12) outcomes. In longitudinal studies, there was an inverse association between fiber intake and depressive outcomes (d = -0.07; 95%CI, -0.11, -0.04). In total, 740 participants were included in 10 RCTs, all of whom used fiber supplements. Of note, only 1 RCT included individuals with a clinical diagnosis of depression. No difference was found between fiber supplementation and placebo for depressive (d = -0.47; 95%CI, -1.26, 0.31) or anxiety (d = -0.30; 95%CI, -0.67, 0.07) outcomes.

CONCLUSION

Although observational data suggest a potential benefit for higher fiber intake for depressive and anxiety outcomes, evidence from current RCTs does not support fiber supplementation for improving depressive or anxiety outcomes. More research, including RCTs in clinical populations and using a broad range of fibers, is needed.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42021274898.

Editorial: Interaction between fibre and colonic fermentation assessed with a novel gas-sensing capsule-Authors' reply

This article is linked to So et al papers. To view these articles, visit https://doi.org/10.1111/apt.17629 and https://doi.org/10.1111/apt.17687

Detection of changes in regional colonic fermentation in response to supplementing a low FODMAP diet with dietary fibres by hydrogen concentrations, but not by luminal pH

BACKGROUND

Carbohydrate fermentation plays a pivotal role in maintaining colonic health with excessive proximal and deficient distal fermentation being detrimental.

AIMS

To utilise telemetric gas- and pH-sensing capsule technologies for defining patterns of regional fermentation following dietary manipulations, alongside conventional techniques of measuring fermentation.

METHODS

In a double-blind crossover trial, 20 patients with irritable bowel syndrome were fed low FODMAP diets that included no extra fibre (total fibre content 24 g/day), or additional poorly fermented fibre, alone (33 g/day) or with fermentable fibre (45 g/day) for 2 weeks. Plasma and faecal biochemistry, luminal profiles defined by tandem gas- and pH-sensing capsules, and faecal microbiota were assessed.

RESULTS

Plasma short-chain fatty acid (SCFA) concentrations (μmol/L) were median (IQR) 121 (100-222) with fibre combination compared with 66 (44-120) with poorly fermented fibre alone (p = 0.028) and 74 (55-125) control (p = 0.069), but no differences in faecal content were observed. Luminal hydrogen concentrations (%), but not pH, were higher in distal colon (mean 4.9 [95% CI: 2.2-7.5]) with fibre combination compared with 1.8 (0.8-2.8) with poorly fermented fibre alone (p = 0.003) and 1.9 (0.7-3.1) control (p = 0.003). Relative abundances of saccharolytic fermentative bacteria were generally higher in association with supplementation with the fibre combination.

CONCLUSIONS

A modest increase in fermentable plus poorly fermented fibres had minor effects on faecal measures of fermentation, despite increases in plasma SCFA and abundance of fermentative bacteria, but the gas-sensing capsule, not pH-sensing capsule, detected the anticipated propagation of fermentation distally in the colon. The gas-sensing capsule technology provides unique insights into localisation of colonic fermentation.

TRIAL REGISTRATION

ACTRN12619000691145.

Comparison of gastrointestinal landmarks using the gas-sensing capsule and wireless motility capsule

BACKGROUND

Accurate definition of the gastroduodenal and ileocaecal junctions (GDJ, ICJ) is essential for the measurement of regional transit times.

AIMS

To compare the assessment of these landmarks using the novel gas-sensing capsule and validated wireless motility capsule (WMC), and to evaluate intra-subject variance in transit times METHODS: Healthy subjects ingested the gas-sensing capsule and WMC tandemly in random order. Inter-observer agreement was evaluated by intra-class correlation coefficient (ICC). Agreement between the paired devices' transit times was assessed using Bland-Altman analysis; coefficient of variation was performed to express intra-individual variance in transit times. Similar analyses were completed with tandemly ingested gas-sensing capsules.

RESULTS

The inter-observer agreement for landmarks for both capsules was excellent (mean ICC ≥0.97) in 50 studies. The GDJ was identifiable in 92% of the gas-sensing capsule studies versus 82% of the WMC studies (p = 0.27); the ICJ in 96% versus 84%, respectively (p = 0.11). In the primary cohort (n = 26), median regional transit times differed by less than 6 min between paired capsules. Bland-Altman revealed a bias of -0.12 (95% limits of agreement, -0.94 to 0.70) hours for GDJ and - 0.446 (-2.86 to 2.0) hours for ICJ. Similar results were found in a demographically distinct validation cohort (n = 24). For tandemly ingested gas-sensing capsules, coefficients of variation of transit times were 11%-35%, which were similar to variance between the paired gas-sensing capsule and WMC, as were the biases. The capsules were well tolerated.

CONCLUSIONS

Key anatomical landmarks are accurately identified with the gas-sensing capsule in healthy individuals. Intra-individual differences in transit times between capsules are probably due to physiological factors. Studies in populations with gastrointestinal diseases are now required.

Supplementing Dietary Fibers With a Low FODMAP Diet in Irritable Bowel Syndrome: A Randomized Controlled Crossover Trial

BACKGROUND & AIMS

Institution of a diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) in patients with irritable bowel syndrome (IBS) may lead to inadequate fiber intake. This trial aimed to investigate the effects of supplementing specific fibers concomitantly with a low FODMAP diet on relevant clinical and physiological indices in symptomatic patients with IBS.

METHODS

A double-blind crossover trial was conducted in which 26 patients with IBS were randomly assigned to 1 of 3 low FODMAP diets differing only in total fiber content: control, 23 g/d; sugarcane bagasse, 33 g/d; or fiber combination (sugarcane bagasse with resistant starch), 45 g/d. Each diet lasted 14 days with most food provided and ≥21 days' washout between. Endpoints were assessed during baseline and dietary interventions.

RESULTS

From a median IBS Severity Scoring System total score at baseline of 305, all diets reduced median scores by >50 with no differences in rates of symptom response between the diets: control (57%), sugarcane bagasse (67%), fiber combination (48%) (P = .459). Stool output was ∼50% higher during the fiber-supplemented vs control diets (P < .001 for both). While there were no overall differences overall in stool characteristics, descriptors, and water content, or in gastrointestinal transit times, supplementation with sugarcane bagasse normalized both low stool water content and slow colonic transit from during the control diet.

CONCLUSIONS

Concomitant supplementation of fibers during initiation of a low FODMAP diet did not alter symptomatic response in patients with IBS but augmented stool bulk and normalized low stool water content and slow transit. Resistant starch did not exert additional symptomatic benefits over sugarcane bagasse alone. (Australia and New Zealand Clinical Trial Registry; Number, ACTRN12619000691145).

Effects of a low FODMAP diet on the colonic microbiome in irritable bowel syndrome: a systematic review with meta-analysis

BACKGROUND

A low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet is increasingly used to manage symptoms in irritable bowel syndrome (IBS). Although this approach may alter the colonic microbiome, the nature of these changes has not been comprehensively synthesized.

OBJECTIVES

The aim of this study was to conduct a systematic review with meta-analysis of randomized controlled trials examining the impact of a low FODMAP diet on the composition and function of the microbiome in patients with IBS.

METHODS

A systematic search was conducted for randomized controlled trials evaluating the effects of a low FODMAP diet on the colonic microbiome in patients with IBS in MEDLINE, EMBASE, CENTRAL, and Web of Science from inception to April 2022. Outcomes included diversity of the microbiome, specific bacterial abundances, fecal SCFA concentration, and fecal pH. For fecal SCFA concentrations and pH, meta-analyses were performed via a random-effects model.

RESULTS

Nine trials involving 403 patients were included. There were no clear effects of the low FODMAP diet on diversity of the microbiome. A low FODMAP diet consistently led to lower abundance of Bifidobacteria, but there were no clear effects on diversity of the microbiome or abundances of other specific taxa. There were no differences in total fecal SCFA concentration between the low FODMAP diet and control diets (standardized mean difference: -0.25; 95% CI: -0.63, 0.13; P = 0.20), nor were there differences for fecal concentrations of specific SCFAs or fecal pH.

CONCLUSIONS

In patients with IBS, the effects of a low FODMAP diet on the colonic microbiome appear to be specific to Bifidobacteria with no consistent impacts on other microbiome metrics, including diversity, fecal SCFA concentrations, and fecal pH. Further, adequately powered trials are needed to confirm these findings.This review was registered at https://www.crd.york.ac.uk/prospero/ as CRD42020192243.

Diet as a therapeutic tool in chronic gastrointestinal disorders: Lessons from the FODMAP journey

BACKGROUND AND AIM

Diet is a powerful tool in the management of gastrointestinal disorders, but developing diet therapies is fraught with challenge. This review discusses key lessons from the FODMAP diet journey.

METHODS

Published literature and clinical experience were reviewed.

RESULTS

Key to designing a varied, nutritionally adequate low-FODMAP diet was our accurate and comprehensive database of FODMAP composition, made universally accessible via our user-friendly, digital application. Our discovery that FODMAPs coexist with gluten in cereal products and subsequent gluten/fructan challenge studies in nonceliac gluten-sensitive populations highlighted issues of collinearity in the nutrient composition of food and confirmation bias in the interpretation of dietary studies. Despite numerous challenges in designing, funding, and executing dietary randomized controlled trials, efficacy of the low-FODMAP diet has been repeatedly demonstrated, and confirmed by real-world experience, giving this therapy credibility in the eyes of clinicians and researchers. Furthermore, real-world application of this diet saw the evolution of a safe and effective three-phased approach. Specialist dietitians must deliver this diet to optimize outcomes as they can target and tailor the therapy and to mitigate the key risks of compromising nutritional adequacy and precipitating disordered eating behaviors, skills outside the gastroenterologist's standard tool kit. While concurrent probiotics are ineffective, specific fiber supplements may improve short-term and long-term outcomes.

CONCLUSIONS

The FODMAP diet is highly effective, but optimal outcomes are contingent on the involvement of a gastroenterological dietitian who can assess, educate, and monitor patients and manage risks associated with implementation of this restrictive diet.

Dietary fibres and IBS: translating functional characteristics to clinical value in the era of personalised medicine

Clinical guidelines in the use of fibre supplementation for patients with IBS provide one-size-fits-all advice, which has limited value. This narrative review addresses data and concepts around the functional characteristics of fibre and subsequent physiological responses induced in patients with IBS with a view to exploring the application of such knowledge to the precision use of fibre supplements. The key findings are that first, individual fibres elicit highly distinct physiological responses that are associated with their functional characteristics rather than solubility. Second, the current evidence has focused on the use of fibres as a monotherapy for IBS symptoms overall without attempting to exploit these functional characteristics to elicit specific, symptom-targeted effects, or to use fibre types as adjunctive therapies. Personalisation of fibre therapies can therefore target several therapeutic goals. Proposed goals include achieving normalisation of bowel habit, modulation of gut microbiota function towards health and correction of microbial effects of other dietary therapies. To put into perspective, bulking fibres that are minimally fermented can offer utility in modulating indices of bowel habit; slowly fermented fibres may enhance the activities of the gut microbiota; and the combination of both fibres may potentially offer both benefits while optimising the activities of the microbiota throughout the different regions of the colon. In conclusion, understanding the GI responses to specific fibres, particularly in relation to the physiology of the individual, will be the future for personalising fibre therapy for enhancing the personalised management of patients with IBS.

Outcomes of patients with high bleeding risks characteristics presenting with acute coronary syndrome undergoing percutaneous coronary intervention

Background

Patients with high bleeding risk characteristics (HBR) presenting with acute coronary syndrome (ACS) pose a clinical challenge to balance risk for recurrent ischemic events versus incurring bleeding with dual antiplatelet therapy.

Purpose

We seek to determine the incidence and predictors of short and long term ischemic and bleeding outcomes in patients with HBR factors presenting with ACS after percutaneous coronary intervention (PCI).

Method

Consecutive patients over a 1-year period, who underwent PCI for ACS were categorized as having HBR based on: age ≥75, anemia (hemoglobin&lt;110g/L), thrombocytopenia (platelet&lt;100x109/L), renal failure (eGFR&lt;30umol/L) or concurrent use of oral anticoagulation. Primary outcome was major adverse cardiovascular event (MACE) defined as composite of cardiovascular death, myocardial infarction, and stroke at 1 year. Key secondary outcomes include significant bleeding defined as Bleeding Academic Research Consortium (BARC) type 3 or 5, and net adverse cardiovascular event (NACE), as a composite of MACE and significant bleeding.

Results

Of 1351 patients presented with ACS, 389 (28.8%) had at least one HBR criteria. At 1 year, patients with HBR, compared to those without, had increased MACE (11.1% vs 4.2%, p&lt;0.001) and cardiovascular death (5.7% vs 1.7%, p&lt;0.001). Patients with HBR had increased significant bleeding (3.6% vs 2.3%, p=0.011) and NACE (14.4% vs 5.4%, p&lt;0.001). Multivariate analysis showed the presence of HBR and prior history of myocardial infarction were predictors for 1-year MACE (OR 2.67, CI [1.62–4.42], p&lt;0.001 and OR 2.18, CI [1.29–3.70], p=0.004, respectively), whereas the use of second-generation antiplatelet agent was not. Increased MACE and NACE were observed in HBR patients beyond 1 month of DAPT.

Conclusion

Among patients with ACS undergoing PCI, those with HBR had higher risk for both ischemic and bleeding complications. Novel strategies need to be considered for this high-risk group. Current guidelines, recommending 1 year of DAPT for patients with ACS, should be re-evaluated among patients with HBR.

Funding Acknowledgement

Type of funding sources: None. Kaplan-Meier curve for 1 year MACEKaplan-Meier curve for 1 year death

Admission triage tool for adult intensive care unit admission in Hong Kong during the COVID-19 outbreak

Intensive care is expensive, and the numbers of intensive care unit (ICU) beds and trained specialist medical staff able to provide services in Hong Kong are limited. The most recent increase in coronavirus disease 2019 (COVID-19) infections over July to August 2020 resulted in more than 100 new cases per day for a prolonged period. The increased numbers of critically ill patients requiring ICU admission posed a capacity challenge to ICUs across the territory, and it may be reasonably anticipated that should a substantially larger outbreak occur, ICU services will be overwhelmed. Therefore, a transparent and fair prioritisation process for decisions regarding patient ICU admission is urgently required. This triage tool is built on the foundation of the existing guidelines and framework for admission, discharge, and triage that inform routine clinical practice in Hospital Authority ICUs, with the aim of achieving the greatest benefit for the greatest number of patients from the available ICU resources. This COVID-19 Crisis Triage Tool is expected to provide structured guidance to frontline doctors on how to make triage decisions should ICU resources become overwhelmed by patients requiring ICU care, particularly during the current COVID-19 pandemic. The triage tool takes the form of a detailed decision aid algorithm based on a combination of established prognostic scores, and it should increase objectivity and transparency in triage decision making and enhance decision-making consistency between doctors within and across ICUs in Hong Kong. However, it remains an aid rather than a complete substitute for the carefully considered judgement of an experienced intensive care clinician.

Effect of Dietary Acetic Acid Supplementation on Plasma Glucose, Lipid Profiles, and Body Mass Index in Human Adults: A Systematic Review and Meta-analysis

BACKGROUND

Acetic acid is a short-chain fatty acid that has demonstrated biomedical potential as a dietary therapeutic agent for the management of chronic and metabolic illness comorbidities. In human beings, its consumption may improve glucose regulation and insulin sensitivity in individuals with cardiometabolic conditions and type 2 diabetes mellitus. Published clinical trial evidence evaluating its sustained supplementation effects on metabolic outcomes is inconsistent.

OBJECTIVE

This systematic review and meta-analysis summarized available evidence on potential therapeutic effects of dietary acetic acid supplementation via consumption of acetic acid-rich beverages and food sources on metabolic and anthropometric outcomes.

METHODS

A systematic search was conducted in Medline, Scopus, EMBASE, CINAHL Plus, and Web of Science from database inception until October 2020. Randomized controlled trials conducted in adults evaluating the effect of dietary acetic acid supplementation for a minimum of 1 week were included. Meta-analyses were performed using a random-effects model on fasting blood glucose (FBG), triacylglycerol (TAG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), glycated hemoglobin (HbA1c), body mass index (BMI), and body fat percentage. Statistical heterogeneity was assessed by calculation of Q and I² statistics, and publication bias was assessed by calculation of Egger's regression asymmetry and Begg's test.

RESULTS

Sixteen studies were included, involving 910 participants who consumed between 750 and 3600 mg acetic acid daily in interventions lasting an average of 8 weeks. Dietary acetic acid supplementation resulted in significant reductions in TAG concentrations in overweight and obese but otherwise healthy individuals (mean difference [MD] = -20.51 mg/dL [95% confidence intervals = -32.98, -8.04], P = .001) and people with type 2 diabetes (MD = -7.37 mg/dL [-10.15, -4.59], P < .001). Additionally, acetic acid supplementation significantly reduced FBG levels (MD = -35.73 mg/dL [-63.79, -7.67], P = .01) in subjects with type 2 diabetes compared with placebo and low-dose comparators. No other changes were seen for other metabolic or anthropometric outcomes assessed. Five of the 16 studies did not specify the dose of acetic acid delivered, and no studies measured blood acetate concentrations. Only one study controlled for background acetic acid-rich food consumption during intervention periods. Most studies had an unclear or high risk of bias.

CONCLUSION

Supplementation with dietary acetic acid is well tolerated, has no adverse side effects, and has clinical potential to reduce plasma TAG and FBG concentrations in individuals with type 2 diabetes, and to reduce TAG levels in people who are overweight or obese. No significant effects of dietary acetic acid consumption were seen on HbA1c, HDL, or anthropometric markers. High-quality, longer-term studies in larger cohorts are required to confirm whether dietary acetic acid can act as an adjuvant therapeutic agent in metabolic comorbidities management.

Transitioning a randomized controlled trial to a digital registry – experience from the TAILOR-PCI digital follow-up study on onboarding, engagement and geofencing consent rate

Background/Introduction

TAILOR-PCI is the largest cardiovascular genotype-based randomized trial (NCT#01742117) investigating whether genotype-guided selection of oral P2Y12 inhibitor therapy improves ischemic outcomes after percutaneous coronary intervention (PCI). The TAILOR-PCI Digital Sub-Study tests the feasibility of extending original follow-up of 1 year to 2 years using state-of-the-art digital solutions. Deep phenotyping acquired during a clinical trial can be leveraged by extending follow-up in an efficient and cost-effective manner using digital technology.

Purpose

Our objective is to describe onboarding and engagement of participants initially recruited in a large, pragmatic, international, multi-center clinical trial to a digital registry.

Methods

TAILOR-PCI participants, within 23 months of their index PCI, were invited by letters containing a URL to the Digital Sub-Study website (http://tailorpci.eurekaplatform.org). These invitations were followed by phone calls, if no response to the letter, to determine reason for non-participation. A NIH-funded direct-to-participant digital research platform (the Eureka Research Platform) was used to onboard, consent and enroll participants for the digital follow-up. Participants were asked to answer health-related surveys at fixed intervals using the Eureka mobile app and desktop platform. To capture hospitalizations, participants could enable geofencing to allow background location tracking, which triggered surveys if a hospitalization was detected.

Result(s)

Letters were mailed to 893 of 929 eligible participants across 22 sites in the United States and Canada leading to 226 homepage visits and 118 registrations. There were 107 consents (12.0% of invited; mean age: 66.4±9.0; 19 females [18%]): 47 (44%) participants consented after the letter, 36 (34%) consented after the 1st call and 24 (22%) consented after a 2nd call. Among those who consented, 100 were eligible (7 did not have a smartphone) 81 downloaded the study mobile app and 73 agreed for geofencing (Figure 1). Among the 722 invited participants who were surveyed, 354 declined participation: due to lack of time (146; 20.2%), lack of smartphone (125; 17.3%), difficulty understanding (41; 5.7%), concern about using smartphone (34; 4.7%), concern of data privacy (14; 1.9%), concerns of location tracking (6; 0.8%) and other reasons (57; 7.9%).

Conclusion

Extended follow-up of a clinical trial using a digital platform is feasible but uptake in this study population was limited largely due to lack of time or a smartphone among participants. Based on data from other digital studies, uptake may also have been limited since digital follow-up consent was not incorporated at the time of consent for the main trial.

Figure 1. Onboarding of the digital substudy

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Institute of Health (NIH), National Heart, Lung, and Blood Institute (NHLBI)

Comparing clinical outcomes following 1 year of dual antiplatelet therapy in patients risk stratified by the PRECISE-DAPT and DAPT scores

Background

Dual antiplatelet therapy (DAPT) is the standard of care following PCI. DAPT reduces ischemic events but increases bleeding risk. Duration of DAPT following PCI remains controversial. Current guidelines recommend duration be individualized based on risk of ischemia and bleeding. Although multiple strategies exist to risk stratify patients, including application of the PRECISE-DAPT and DAPT scores, there is currently no standardized risk assessment protocol.

Purpose

To determine if the PRECISE-DAPT and DAPT scores can identify patients at increased risk of ischemia or bleeding in a cohort prescribed 12 months of DAPT following PCI.

Methods

We calculated the PRECISE-DAPT and DAPT scores for 469 consecutive patients at baseline after PCI. Patients were grouped based on score treatment recommendation; PRECISE-DAPT prolonged or shortened (PRECISE DAPT &lt;25 vs. ≥25) and DAPT prolonged or shortened (DAPT ≥2 vs &lt;2). End points included 1-year rates of major adverse cardiovascular events (MACE) and TIMI major or minor bleeding.

Results

Among 469 patients, mean age was 64.4 (SD 12.2); 102 (21.7%) were women. Index presentation consisted of a STEMI in 207 (44.1%), NSTEMI in 99 (21.1%), and UA in 60 (12.8%). At presentation, 174 (37.1%) were current smokers, 115 (24.5%) had a prior MI, 118 (25.2%) had diabetes, 249 (53.1%) had dyslipidemia and 281 (60.0%) were previously diagnosed as hypertensive. Overall, there was an increase in bleeding and no difference in MACE for patients with a PRECISE-DAPT score ≥25 (13.3% vs. 4.1% P&lt;0.001). No difference in bleeding or MACE was present in patients stratified by the DAPT score.

Conclusion

A PRECISE-DAPT score ≥25 was associated with an increased rate of bleeding and no difference in MACE in patients prescribed 12 months of DAPT. This supports the use of the PRECISE-DAPT as a prospective tool in clinical practice.

Funding Acknowledgement

Type of funding source: None

The effect of exercise interventions on resting metabolic rate: A systematic review and meta-analysis

The systematic review and meta-analysis evaluated the effect of aerobic, resistance and combined exercise on RMR (kCal·day^-1) and performed a methodological assessment of indirect calorimetry protocols within the included studies. Subgroup analyses included energy/diet restriction and body composition changes. Randomized control trials (RCTs), quasi - RCTs and cohort trials featuring a physical activity intervention of any form and duration excluding single exercise bouts were included. Participant exclusions included medical conditions impacting upon RMR, the elderly (≥65 years of age) or pregnant, lactating or post-menopausal women. The review was registered in the International Prospective Register of Systematic Reviews (CRD 42,017,058,503). 1669 articles were identified; 22 were included in the qualitative analysis and 18 were meta-analysed. Exercise interventions (aerobic and resistance exercise combined) did not increase resting metabolic rate (mean difference (MD): 74.6 kCal·day^-1[95% CI: -13.01, 161.33], P = 0.10). While there was no effect of aerobic exercise on RMR (MD: 81.65 kCal·day^-1[95% CI: -57.81, 221.10], P = 0.25), resistance exercise increased RMR compared to controls (MD: 96.17 kCal·day^-1[95% CI: 45.17, 147.16], P = 0.0002). This systematic review effectively synthesises the effect of exercise interventions on RMR in comparison to controls; despite heterogenous methodologies and high risk of bias within included studies.

Impact of electronic bedside meal ordering systems on dietary intake, patient satisfaction, plate waste and costs: A systematic literature review

Aim

Hospital foodservices provide an important opportunity to deliver valuable dietary support to patients, address hospital‐acquired malnutrition risk and enhance patient satisfaction. Modifying the meal ordering process through the adoption of technology may actively engage patients in the process and provide an opportunity to influence patient and organisational outcomes. This systematic review was undertaken to evaluate the impact of electronic bedside meal ordering systems in hospitals on patient dietary intake, patient satisfaction, plate waste and costs.

Methods

A systematic search following PRISMA guidelines was conducted across MEDLINE, CINAHL, EMBASE and Web of Science for randomised controlled trials and observational studies comparing the effect of electronic bedside meal ordering systems with traditional menus on dietary intake, patient satisfaction, plate waste and cost. The quality of included studies was assessed using the Quality Criteria Checklist for Primary Research tool.

Results

Five studies involving 720 patients were included. Given the heterogeneity of the included studies, the results were narratively synthesised. Electronic bedside meal ordering systems positively impacted patient dietary intake, patient satisfaction, plate waste and costs compared with traditional menus.

Conclusions

Despite the increase in healthcare foodservices adopting digital health solutions, there is limited research specifically measuring the impact of electronic bedside meal ordering systems on patient and organisational outcomes. This study highlights potential benefits of electronic bedside meal ordering systems for hospitals using traditional paper menu systems, while also identifying the need for continued research to generate evidence to understand the impact of this change and inform future successful innovations.

P1933Comparing treatment recommendations for the DAPT and PRECISE-DAPT scores after percutaneous coronary intervention

Background

Dual antiplatelet therapy (DAPT), with aspirin and a P2Y12 inhibitor, is the standard therapy for patients following PCI. Duration of treatment with DAPT has been controversial despite large studies. Current guidelines recommend treatment duration be individualized based on risk of ischemia and bleeding. To facilitate treatment decisions, risk assessment tools, including the DAPT and PRECISE-DAPT scores, have been developed.

Purpose

As components of these scores differ, the variability of recommendation remains unknown. We set to evaluate inter-tool concordance in treatment recommendation in a cohort of patients after PCI.

Methods

Using data from our local PCI registry, we calculated the PRECISE-DAPT at baseline following PCI and the DAPT after 1 year of treatment for 311 consecutive patients with complete data for both scores to be calculated. Based on their DAPT and PRECISE-DAPT scores, patients were grouped into concordant for long-term treatment (DAPT ≥2 and PRECISE-DAPT <25) or concordant for shortened treatment (DAPT <2 and PRECISE- DAPT ≥25). All other patients were considered discordant. We then performed a concordance analysis using Cohen's kappa to measure degree of agreement.

Results

Among the 311 patients, mean age was 63.4 (SD 11.6); 245 (79%) were men, 93 (29.9%) had history of a prior MI, 130 (41.8%) were current smokers, 32 (10.3%) had a history of CHF or LVEF <30%, 82 (26.3%) had diabetes and 196 (63.0%) were previously diagnosed with hypertension. Index event consisted of a STEMI in 101 (32.4%), NSTEMI in 93 (29.9%), unstable angina in 27 (8.7%), stable angina in 67 (21.5%) and the remaining 23 (7.4%) had other indications for PCI. Mean DAPT score was 1.52 (SD 1.37). Mean PRECISE-DAPT was 17.65 (SD 12.73). The DAPT recommended long-term treatment for 162 (52.1%) and shortened treatment for 149 (47.9%). The PRECISE-DAPT recommended long-term treatment for 245 (78.9%) and shortened treatment for 66 (21.2%). The overall proportion of agreement between the two risk scores was 56.6% with a Cohen's kappa index of 0.110 (95% CI, 0.017 to 0.204). See Table.

Concordance Analysis PRECISE-DAPT Score Recommendation Long Term (N=245) Shortened (N=66) DAPT Score Recommendation Long Term (N=162) 136 (43.7%) 26 (8.4%) Concordant for Long Term Treatment Shortened (N=149) 109 (35%) 40 (12.8%) Concordant for Shortened Treatment

Conclusion

Comparison of the DAPT score and the PRECISE-DAPT score showed concordance in treatment recommendation in only 56.6% of patients. Given the poor agreement between these tools, prospective concurrent evaluations and correlation to outcomes will be required in future studies.

Dietary fiber intervention on gut microbiota composition in healthy adults: a systematic review and meta-analysis

Background

Dysfunction of the gut microbiota is frequently reported as a manifestation of chronic diseases, and therefore presents as a modifiable risk factor in their development. Diet is a major regulator of the gut microbiota, and certain types of dietary fiber may modify bacterial numbers and metabolism, including short-chain fatty acid (SCFA) generation.

Objective

A systematic review and meta-analysis were undertaken to assess the effect of dietary fiber interventions on gut microbiota composition in healthy adults.

Design

A systematic search was conducted across MEDLINE, EMBASE, CENTRAL, and CINAHL for randomized controlled trials using culture and/or molecular microbiological techniques evaluating the effect of fiber intervention on gut microbiota composition in healthy adults. Meta-analyses via a random-effects model were performed on alpha diversity, prespecified bacterial abundances including Bifidobacterium and Lactobacillus spp., and fecal SCFA concentrations comparing dietary fiber interventions with placebo/low-fiber comparators.

Results

A total of 64 studies involving 2099 participants were included. Dietary fiber intervention resulted in higher abundance of Bifidobacterium spp. (standardized mean difference (SMD): 0.64; 95% CI: 0.42, 0.86; P < 0.00001) and Lactobacillus spp. (SMD: 0.22; 0.03, 0.41; P = 0.02) as well as fecal butyrate concentration (SMD: 0.24; 0.00, 0.47; P = 0.05) compared with placebo/low-fiber comparators. Subgroup analysis revealed that fructans and galacto-oligosaccharides led to significantly greater abundance of both Bifidobacterium spp. and Lactobacillus spp. compared with comparators (P < 0.00001 and P = 0.002, respectively). No differences in effect were found between fiber intervention and comparators for α-diversity, abundances of other prespecified bacteria, or other SCFA concentrations.

Conclusions

Dietary fiber intervention, particularly involving fructans and galacto-oligosaccharides, leads to higher fecal abundance of Bifidobacterium and Lactobacillus spp. but does not affect α-diversity. Further research is required to better understand the role of individual fiber types on the growth of microbes and the overall gut microbial community. This review was registered at PROSPERO as CRD42016053101.

Solid-state colloidal CuInS2 quantum dot solar cells enabled by bulk heterojunctions

Colloidal copper indium sulfide (CIS) nanocrystals (NCs) are Pb- and Cd-free alternatives for use as absorbers in quantum dot solar cells. In a heterojunction with TiO₂, non-annealed ligand-exchanged CIS NCs form solar cells yielding a meager power conversion efficiency (PCE) of 0.15%, with photocurrents plummeting far below predicted values from absorption. Decreasing the amount of zinc during post-treatment leads to improved mobility but marginal improvement in device performance (PCE = 0.30%). By incorporating CIS into a porous TiO₂ network, we saw an overall drastic improvement in device performance, reaching a PCE of 1.16%, mainly from an increase in short circuit current density (J_sc) and fill factor (FF) and a 10-fold increase in internal quantum efficiency (IQE). We have determined that by moving from a bilayer to a bulk heterojunction architecture, we have reduced the trap-assisted recombination as seen in changes in the ideality factor, the intensity dependence of the photocurrent and transient photocurrent (TPC) and photovoltage (TPV) characteristics.

The PR status of the originating cell of ER/PR-negative mouse mammary tumors

Progesterone receptor (PR) is usually co-localized with estrogen receptor (ER) in normal mammary cells. It is not known whether ER/PR-negative human breast cancer arises from an ER/PR-negative cell or from an ER/PR-positive cell that later lost ER/PR. Using intraductal injection of a lentivirus to deliver both an oncogene (ErbB2) and a floxed green fluorescent protein (GFP) in PR(Cre/+)mice, whose Cre gene is under the control of the PR promoter, we were able to trace the PR status of the infected cells as they progressed to cancer. We found that the resulting early lesions stained negative for PR in most of the cells and usually retained GFP. The resulting tumors lacked ER and PR, and 75% (15/20) of them retained the GFP signal in all tumor cells, suggesting PR was never expressed throughout the evolution of a majority of these tumors. In conclusion, our data demonstrate that ErbB2-initiated ER/PR-negative mammary tumors primarily originate from the subset of the mammary epithelium that is negative for PR and probably ER as well. These findings also provide an explanation for why antihormonal therapy fails to prevent ER-negative breast cancers.