From detection methods to risk prevention: Control of N-nitrosamines in foods and the role of natural bioactive compounds.

Food processing unavoidably introduces various risky ingredients that threaten food safety. N-Nitrosamines (NAs) constitute a class of food contaminants, which are considered carcinogenic to humans. According to the compiled information, pretreatment methods based on solid-phase extraction (SPE) were widely used before the determination of volatile NAs in foods. The innovation of adsorbents and hybridization of other methods have been confirmed as the future trends of SPE-based pretreatment methods. Moreover, technologies based on liquid chromatography and gas chromatography were popularly applied for the detection of NAs. Recently, sensor-based methods have garnered increasing attention due to their efficiency and flexibility. More portable sensor-based technologies are recommended for on-site monitoring of NAs in the future. The application of artificial intelligence can facilitate data processing during high-throughput detection of NAs. Natural bioactive compounds have been confirmed to be effective in mitigating NAs in foods through antioxidation, scavenging precursors, and regulating microbial activities. Meanwhile, they exhibit strong protective activities against hepatic damage, pancreatic cancer, and other NA injuries. Further supplementation of data on the bioavailability of bioactives can be achieved through encapsulation and clinical trials. The utilization of bioinformatics tools rooted in various omics technologies is suggested for investigating novel mechanisms and finally broadening their applications in targeted therapies.

Why Have We Not Been Able to Demonstrate Reduced Mortality in Patients With HFmrEF/HFpEF?

No randomized controlled trial has yet demonstrated a statistically significant reduction in mortality in patients with heart failure and mildly reduced ejection (HFmrEF) or heart failure and preserved ejection fraction (HFpEF), in contrast to the benefits observed in heart failure with reduced ejection fraction (HFrEF). However, this probably reflects the statistical power of trials to date to show an effect on mortality rather than mechanistic differences between HFmEF/HFpEF and HFrEF or differences in treatment efficacy. Compared to patients with HFrEF, those with HFmrEF/HFpEF have lower mortality rates and a smaller proportion of potentially modifiable cardiovascular deaths (as opposed to unmodifiable noncardiovascular deaths). In addition, some causes of cardiovascular deaths may not be reduced by treatments for HF. Therefore, the low rate of potentially modifiable deaths in patients with HFmrEF/HFpEF, compared with HFrEF, has made it challenging to demonstrate a reduction in death (or cardiovascular death) in trials to date.

Janus kinase inhibitors versus tumor necrosis factor inhibitors in rheumatoid arthritis: meta-analytical comparison of efficacy and safety.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic systemic autoimmune disorder characterized by persistent inflammation leading to progressively worse disability. Janus kinase (JAK) inhibitors and tumor necrosis factor (TNF) inhibitors are pivotal in RA treatment, yet their comparative efficacy remains underexplored. AIM: This study aimed to compare the efficacy and safety of JAK inhibitors and TNF inhibitors in treating RA using data from randomized controlled trials (RCTs). METHODS: A meta-analysis and outcomes analysis were based on results of the Health Assessment Questionnaire Disability Index (HAQ-DI), Clinical Disease Activity Index (CDAI), Visual Analogue Scale (VAS), and Patient Global Assessment Scale (PtGA) and other indices as incidences of venous thromboembolism (VTE) and malignancy. RESULTS: The JAK inhibitors caused a statistically significant improvement in the HAQ-DI score [MD = 0.08, 95% CI (0.03, 0.12), p = 0.0008] compared with the TNF inhibitors. However, no significant difference was observed between the two drug classes in the CDAI score [MD = - 2.03, 95% CI (- 9.27, 5.22), p = 0.58]. JAK inhibitors were associated with an increase in the VAS score [MD = 3.62, 95% CI (0.86, 6.38), p = 0.01], but there was no significant difference in the PtGA score [MD = 1.91, 95% CI (- 3.25, 7.08), p = 0.47]. CONCLUSION: JAK inhibitors demonstrated superior efficacy in improving the functional status and reducing the disease activity in RA patients compared with TNF inhibitors. Both drug classes exhibited comparable safety profiles for VTE and malignancies, though JAK inhibitors had a higher risk for thromboembolism.

Why have status epilepticus trials failed: Wrong drugs or wrong trials?

Despite burgeoning interest in trials in status epilepticus over the last 20 years, outcomes have yet to improve and a number of high profile studies have failed to deliver for a range of reasons. The range of reasons a trial may fail to meet the intended outcomes are discussed. Recent well designed, adequately powered studies in established status epilepticus failed to meet primary endpoints, but are nonetheless influencing practice, reflecting the importance of interpreting results in the context of broader literature, safety and practical considerations. Studies in refractory and super-refractory status epilepticus have yet to do so, frequently failing to deliver as hoped despite huge financial and human cost. The importance of reviewing regulatory frameworks, and our approach to trial design to address important clinical questions is reviewed, reflecting on lessons from the COVID-19 RECOVERY trials, and other disease areas, together with the potential associated with the use artificial intelligence tools. This paper is based on a presentation made at the 9th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures in April 2024.

The usefulness of randomized trials of lifestyle interventions for overweight, obesity, or metabolic syndrome: A systematic review.

BACKGROUND: Randomised controlled trials (RCTs) widely considered the gold standard for evidence-based healthcare may be limited in their clinical usefulness in lifestyle interventions for adults with overweight, obesity, or metabolic syndrome. OBJECTIVE: In this systematic review of lifestyle intervention RCTs we delineated trial usefulness. METHODS: Following prospective registration in PROSPERO (CRD4202347896), we conducted a comprehensive search across Medline, Scopus, Web of Science, and the Cochrane Library databases, covering the period from inception to December 2023. RCTs involving dietary interventions, with or without physical activity, and with or without behavioural support were included. Two reviewers independently performed study selection and data extraction. Study usefulness was assessed using a multidimensional 14 item questionnaire. Percentage compliance with usefulness items was computed. RESULTS: Of 1175 records, 30 RCTs (12841 participants) were included. Among these, 13 (43%) RCTs complied with half of the usefulness items and only 3 (10%) complied with two-thirds of the items. For each usefulness item individually: 30 (100%) reported the burden of the problem addressed, 15 (50%) contextualized the trial through a systematic review, 18 (60%) presented an informative trial with clinically meaningful outcomes evaluated at a stated statistical power, 17 (57%) had low risk of bias, 2 (7%) exhibited pragmatic features pertaining to the trial methodologies and outcomes relevant to real-world application.18 (60%) were patient centred with formal patient involvement, none (0%) demonstrated value for money, 17 (57%) were completed according to their feasibility assessment achieving at least 90% of the estimated sample size, and 30 (100%) reported at least one of five transparency or openness features. CONCLUSION: Only one in 10 lifestyle RCTs met two-thirds of the usefulness features. It is imperative to meet these criteria when devising future trials within the field of nutrition to reduce research waste.

The ADNI4 Digital Study: A novel approach to recruitment, screening, and assessment of participants for AD clinical research.

INTRODUCTION: We evaluated preliminary feasibility of a digital, culturally-informed approach to recruit and screen participants for the Alzheimer's Disease Neuroimaging Initiative (ADNI4). METHODS: Participants were recruited using digital advertising and completed digital surveys (e.g., demographics, medical exclusion criteria, 12-item Everyday Cognition Scale [ECog-12]), Novoic Storyteller speech-based cognitive test). Completion rates and assessment performance were compared between underrepresented populations (URPs: individuals from ethnoculturally minoritized or low education backgrounds) and non-URPs. RESULTS: Of 3099 participants who provided contact information, 654 enrolled in the cohort, and 595 completed at least one assessment. Two hundred forty-seven participants were from URPs. Of those enrolled, 465 met ADNI4 inclusion criteria and 237 evidenced possible cognitive impairment from ECog-12 or Storyteller performance. URPs had lower ECog and Storyteller completion rates. Scores varied by ethnocultural group and educational level. DISCUSSION: Preliminary results demonstrate digital recruitment and screening assessment of an older diverse cohort, including those with possible cognitive impairment, are feasible. Improving engagement and achieving educational diversity are key challenges. HIGHLIGHTS: A total of 654 participants enrolled in a digital cohort to facilitate ADNI4 recruitment. Culturally-informed digital ads aided enrollment of underrepresented populations. From those enrolled, 42% were from underrepresented ethnocultural and educational groups. Digital screening tools indicate > 50% of participants likely cognitively impaired. Completion rates and assessment performance vary by ethnocultural group and education.

Epithelial­derived head and neck squamous tumourigenesis (Review).

Head and neck squamous cell carcinomas (HNSCCs), a heterogeneous group of cancers that arise from the mucosal epithelia cells in the head and neck areas, present great challenges in diagnosis, treatment and prognosis due to their complex aetiology and various clinical manifestations. Several factors, including smoking, alcohol consumption, oncogenic genes, growth factors, Epstein­Barr virus and human papillomavirus infections can contribute to HNSCC development. The unpredictable tumour microenvironment adds to the complexity of managing HNSCC. Despite significant advances in therapies, the prediction of outcome after treatment for patients with HNSCC remains poor, and the 5­year overall survival rate is low due to late diagnosis. Early detection greatly increases the chances of successful treatment. The present review aimed to bring together the latest findings related to the molecular mechanisms of HNSCC carcinogenesis and progression. Comprehensive genomic, transcriptomic, metabolomic, microbiome and proteomic analyses allow researchers to identify important biological markers such as genetic alterations, gene expression signatures and protein markers that drive HNSCC tumours. These biomarkers associated with the stages of initiation, progression and metastasis of cancer are useful in the management of patients with cancer in order to improve their life expectancy and quality of life.

Collecting and reporting adverse events in low-income settings-perspectives from vaccine trials in the Gambia.

BACKGROUND: Despite Africa's significant infectious disease burden, it is underrepresented in global vaccine clinical trials. While this trend is slowly reversing, it is important to recognize and mitigate the challenges that arise when conducting vaccine clinical trials in this environment. These challenges stem from a variety of factors peculiar to the population and may negatively impact adverse event collection and reporting if not properly addressed. METHODS: As a team of clinical researchers working within the MRCG (Medical Research Council Unit The Gambia), we have conducted 12 phase 1 to 3 vaccine trials over the past 10 years. In this article, we discuss the challenges we face and the strategies we have developed to improve the collection and reporting of adverse events in low-income settings. OUTCOME: Healthcare-seeking behaviors in the Gambia are influenced by spiritual and cultural beliefs as well as barriers to accessing orthodox healthcare; participants in trials may resort to non-orthodox care, reducing the accuracy of reported adverse events. To address this, trial eligibility criteria prohibit self-treatment and herbal product use during trials. Instead, round-the-clock care is provided to trial participants, facilitating safety follow-up. Constraints in the healthcare system in the Gambia such as limitations in diagnostic tools limit the specificity of diagnosis when reporting adverse events. To overcome these challenges, the Medical Research Council Unit maintains a Clinical Services Department, offering medical care and diagnostic services to study participants. Sociocultural factors, including low literacy rates and social influences, impact adverse event collection. Solicited adverse events are collected during home visits on paper-based or electronic report forms. Community engagement meetings are held before each study starts to inform community stakeholders about the study and answer any questions they may have. These meetings ensure that influential members of the community understand the purpose of the study and the risks and benefits of participating in the trial. This understanding makes them more likely to support participation within their communities. CONCLUSION: Conducting ethical vaccine clinical trials in resource-limited settings requires strategies to accurately collect and report adverse events. Our experiences from the Gambia offer insights into adverse event collection in these settings.

Mesenchymal stem cells: A promising therapeutic avenue for non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is a pressing global health concern that is associated with metabolic syndrome and obesity. On the basis of the insights provided by Jiang et al, this editorial presents an exploration of the potential of mesenchymal stem cells (MSCs) for NAFLD treatment. MSCs have numerous desirable characteristics, including immunomodulation, anti-inflammatory properties, and tissue regeneration promotion, rendering them attractive candidates for NAFLD treatment. Recent preclinical and early clinical studies have highlighted the efficacy of MSCs in improving liver function and reducing disease severity in NAFLD models. However, MSC heterogeneity, long-term safety concerns, and unoptimized therapeutic protocols remain substantial challenges. Addressing these challenges through standardized protocols and rigorous clinical trials is essential to the safe and successful application of MSCs in NAFLD management. Continued research into MSC mechanisms and therapeutic optimization is required to improve treatments for NAFLD and related liver diseases.

Oncology Early-Phase Clinical Trials in the Middle East and North Africa: A Review of the Current Status, Challenges, Opportunities, and Future Directions.

Clinical trials, the empirical discipline of medical experimentation conducted on human subjects, have engendered a paradigm shift in medical research. The need for new clinical studies is paramount in the Middle East and North Africa (MENA) region, with its rising cancer incidence and demand for efficient oncology treatments. This paper comprehensively reviews the challenges, opportunities, and future directions of phase I oncology clinical trials in the MENA region. Early-phase trials are vital in determining drug dosage and assessing toxicity, bridging the gap between preclinical research and clinical practice. Considering the unique landscape of MENA, this review explores regulatory aspects, specific hurdles faced, potential advantages, and areas for improvement in conducting these trials. Various future directions can be pursued to maximize the potential of phase I oncology trials in MENA. While regulatory bodies like the Ministry of Health adhere to the International Conference on Harmonization-Good Clinical Practice guidelines, a unified system meeting high standards would yield better results. Strengthening research infrastructure, establishing research centers, incorporating clinical trial education into the curriculum, and improving access to medical facilities are crucial. Enhancing consumer understanding of research would facilitate increased participation and promote sustainability in trial recruitment. Navigating various funding sources would open the door for more funding opportunities. Collaborations between academia, industry, and regulatory bodies, both international and local, should be fostered to promote knowledge sharing, resource pooling, and harmonization of standards. Such collaborations would contribute to the sustainability of clinical trial activities by leveraging collective expertise, sharing research infrastructure, and distributing the burden of regulatory compliance. By adopting these strategies, the MENA region can advance its capacity to conduct early phases of oncology trials and contribute significantly to the global medical research landscape.

Decentralized Clinical Trials in Early Drug Development-A Framework Proposal.

The COVID-19 pandemic has led to a rethinking of clinical trial design to maintain clinical research activity, with regulatory changes allowing for the wider implementation and development of decentralized design models. Evidence of the feasibility and benefits associated with a remote design comes mainly from observational studies or phase 2 and 3 clinical trials, in which implementation is easier with a better-established safety profile. Early drug development is a slow and expensive process in which accrual and safety are key aspects of success. Applying a decentralized model to phase 1 clinical trials could improve patient accrual by removing geographic barriers, improving patient population diversity, strengthening evidence for rare tumors, and reducing patients' financial and logistical burdens. However, safety monitoring, data quality, shipment, and administration of the investigational product are challenges to its implementation. Based on published data for decentralized clinical trials, we propose an exploratory framework of solutions to enable the conceptualization of a decentralized model for phase 1 clinical trials.

Early phase clinical trials in pediatric oncology: Swedish pediatric oncologists' experiences of balancing hope and expectations in life-threatening illnesses.

Aim: To study Swedish pediatric oncologists' practical and emotional experiences of referring, including and/or treating children in early-phase clinical trials. Methods: A nationwide study was conducted using a mixed-method approach. Structured interviews based on a study-specific questionnaire and participants' personal reflections were utilized. Survey responses were analyzed using descriptive statistics, while participants' comments were analyzed using thematic analysis. All interviews were recorded and transcribed verbatim. Results: In total, 29 physicians with 4 to 32 years of experience in pediatric oncology participated, with 19 (66%) having > 10 years of experience. Three themes appeared: 1) Optimization-based approach focused on finding the most suitable treatment and care for every child with a refractory/relapsed cancer eligible for an early-phase clinical trial; 2) Team-based approach aimed at establishing local and national consensus in decision-making for treatment options, including early-phase clinical trials and palliative care; 3) Family-based approach in which the physicians provided families with actionable information, listened to their desires, and endeavored to maintain hope in challenging circumstances. Several participants (40% with ≤ 10 years of experience and 58% with > 10 years of experience) viewed the early-phase clinical trial as a potential "chance of cure". A majority (80%) of physicians with ≤ 10 years of experience, reported that they often or always felt personally and emotionally affected by communication regarding early-phase clinical trials. Delivering difficult news in cases of uncertain prognosis was identified as the major challenge. None of the study participants felt adequately prepared in terms of sufficient knowledge and experience regarding early-phase clinical trials. The physicians expressed a need for guidance and training in communication to address these challenges. Conclusions: Working with early-phase clinical trials highlight a field where physicians cannot solely rely on their expertise or past experiences, and where they are likely to be deeply emotionally involved. Physicians who care for children eligible for such studies require targeted educational initiatives and supervision.

Feasibility and acceptability of the ShareD dEciSIon making for patients with kidney failuRE to improve end-of-life care intervention: A pilot multicentre randomised controlled trial.

Background: Kidney failure is associated with a high disease burden and high mortality rates. National and international guidelines recommend health professionals involve patients with kidney failure in making decisions about end-of-life care, but implementation of these conversations within kidney services varies. We developed the DESIRE (ShareD dEciSIon-making for patients with kidney failuRE to improve end-of-life care) intervention from our studies investigating multiple decision maker needs and experiences of end-of-life care in kidney services. The DESIRE intervention's three components are a training programme for health professionals, a patient decision aid, and a kidney service consultation held to facilitate shared decision-making conversations about planning end-of-life care. Objectives: To assess the feasibility and acceptability of integrating the DESIRE intervention within kidney services. Design: A pilot study using a multicentre randomised controlled design. Setting: Four Danish nephrology departments. Participants: Patients with kidney failure who were 75 years of age or above, their relatives, and health professionals. Methods: Patients were randomised to either the intervention or usual care. Feasibility data regarding delivering the intervention, the trial design, and outcome measures were collected through questionnaires and audio recordings at four points in time: before, during, post, and 3 months after the intervention. Acceptability data were collected through semi-structured interviews with patients and relatives, as well as a focus group with health professionals post the intervention. Results: Twenty-seven patients out of the 32 planned were randomised either to the intervention (n= 14) or usual care (n= 13). In addition, four relatives and 12 health professionals participated. Follow-up was completed by 81 % (n= 22) of patient participants. We found that both feasibility and acceptability data suggested health professionals improved their decision support and shared decision-making skills via the training. Patient and relative participants experienced the intervention as supporting a shared decision-making process; from audio recordings, we showed health professionals were able to support proactively decision-making about end-of-life care within these consultations. All stakeholders perceived the intervention to be effective in promoting shared decision-making and relevant for supporting end-of-life care planning. Conclusions: Participant feedback indicated that the DESIRE intervention can be integrated into practice to support patients, relatives, and health professionals in planning end-of-life care alongside the management of worsening kidney failure. Minimising exhaustion and enhancing engagement with the intervention should be a focus for subsequent refinement of the intervention. Registration: The study has been registered at ClinicalTrials.gov with the identifier: NCT05842772. Date of first recruitment: March 20, 2023.

Efficacy of lifestyle weight loss interventions on regression to normoglycemia and progression to type 2 diabetes in individuals with prediabetes: a systematic review and pairwise and dose-response meta-analyses.

BACKGROUND: Current recommendations for weight loss in individuals with prediabetes come from individual trials and are derived from older data. OBJECTIVE: To elucidate the dose-dependent impacts of weight loss on participants with prediabetes to determine the optimal magnitude of weight loss required for the implementation of the most effective diabetes prevention program. METHODS: We searched PubMed, Scopus, CENTRAL, CINAHL, and grey literature sources to September 2023 for randomized trials ≥6 months that evaluated the efficacy of a lifestyle weight loss intervention on participants with prediabetes. We conducted random-effects pairwise meta-analyses to calculate relative and absolute effects. We performed one-stage weighted mixed-effects meta-analysis to elucidate the dose-response curves. RESULTS: 44 randomized trials with 14,742 participants with prediabetes (intervention duration range: 6 to 72 months [median=24 months], average weight loss range: 1% to 9%) were included. Lifestyle weight loss interventions increased regression to normoglycemia by 11 per 100 participants (95%CI: 8 more, 17 more; risk ratio: 1.51, 95%CI: 1.27, 1.80; n=20 trials, GRADE=moderate), and reduced progression to type 2 diabetes by 8 per 100 participants (95%CI: 11 fewer, 6 fewer; risk ratio: 0.59, 95%CI: 0.51, 0.67; n=37, GRADE=moderate). There were no significant or credible differences among subgroups categorized by the type and duration of intervention. Dose-response meta-analyses indicated that the risk of regression to normoglycemia increased and the risk of progression to type 2 diabetes declined in a linear pattern within the range of weight loss from 1% to 9%. CONCLUSIONS: Over a median duration of 24 months, with weight loss ranging from 1% to 9%, the relationship between weight loss and the progression to type 2 diabetes, as well as the regression to normoglycemia, follows a linear pattern. Any form of lifestyle weight loss interventions including diet, exercise, or a combination of both, can have beneficial impacts on participants with prediabetes. PROTOCOL REGISTRATION: PROSPERO (CRD42023465322).

Surrogate endpoint meta-regression: Useful statistics for regulators and trialists.

OBJECTIVES: The main purpose of using a surrogate endpoint is to estimate the treatment effect on the true endpoint sooner than with a true endpoint. Based on a meta-regression of historical randomized trials with surrogate and true endpoints, we discuss statistics for applying and evaluating surrogate endpoints. METHODS: We computed statistics from two types of linear meta-regressions for trial-level data: simple random effects and novel random effects with correlations among estimated treatment effects in trials with more than 2 arms. A key statistic is the estimated intercept of the meta-regression line. An intercept that is small or not statistically significant increases confidence when extrapolating to a new treatment because of consistency with a single causal pathway and invariance to labeling of treatments as controls. For a regulator applying the meta-regression to a new treatment, a useful statistic is the 95% prediction interval. For a clinical trialist planning a trial of a new treatment, useful statistics are the surrogate threshold effect proportion, the sample size multiplier adjusted for dropouts, and the novel true endpoint advantage. RESULTS: We illustrate these statistics with surrogate endpoint meta-regressions involving anti-hypertension treatment, breast cancer screening, and colorectal cancer treatment. CONCLUSION: Regulators and trialists should consider using these statistics when applying and evaluating surrogate endpoints.

The use of composite endpoints in cardiovascular outcome trials for diabetes: A review of 22 randomized clinical trials published since 2008.

AIM: To describe the use of composite endpoints (CEs) in cardiovascular outcome trials (CVOTs) of type 2 diabetes and to evaluate the significance of the individual outcomes included within these CEs from the perspectives of both patients and clinicians. Secondary objectives were to estimate the gradient of treatment effects and events across outcomes. MATERIALS AND METHODS: Eligible studies were randomized controlled trials assessing CV outcomes for patients with diabetes from 2008 and onwards. Trials were identified by searching the reports from the CVOT Summit of the Diabetes & CV Disease EASD (European Association for the Study of Diabetes) Study Group. The individual outcomes comprising the CE were compared for differences in importance for patients and clinicians, proportion of events, and effect size. RESULTS: We included 22 trials randomizing a mean of 8098 patients to an active intervention or a comparator group for an average of 33 months (standard deviation 16). All primary outcomes were CEs, and from a patient perspective there was no gradient of importance across outcomes in 22 of 22 (100%) CEs, while the gradient was small in 22 of 22 (100%) from a clinician perspective. The gradient of effect was moderate to large in 9 of 18 (50%) reporting studies, while assessment of events was available in 15 of 22 studies (68%), finding that three of 15 (20%) had a gradient of effect of more than 5% points between included outcomes. In 10 of 22 (45%) trial reports, the results were not clearly presented as based on a CE. CONCLUSIONS: To avoid misinterpretation, clinicians and regulatory authorities should be careful when interpreting the results of trials, of which the main outcomes are CEs.

Outcomes of robotic versus laparoscopic-assisted surgery in patients with rectal cancer: a systematic review and meta-analysis.

PURPOSE: Robotic-assisted rectal surgery (RARS) and Laparoscopic-assisted rectal surgery are the two techniques that are increasingly used for rectal cancer, and both have their advantages and disadvantages. This meta-analysis will analyze the outcomes of both techniques to determine their relative performance and suitability. METHODS: An extensive search was carried out on PubMed, Cochrane, Scopus, Embase, and Google Scholar, followed by a meta-analysis of all randomized controlled trials (RCTs) to assess both approaches for rectal cancer. RESULTS: This meta-analysis is comprised of fifteen RCTs. The conversion to open surgery (RR = 0.53, 95% CI: 0.38-0.74, P = 0.0002) was significantly lower in the RARS group. The outcomes like anastomotic leak, postoperative ileus, postoperative urinary retention (POUR), surgical site infection (SSI), and intra-abdominal abscess showed no significant difference between the two groups. The reoperation rate (RR = 0.56, 95% CI: 0.34-0.95, P = 0.03) was lower in the robotic group. High heterogeneity was obtained when pooling data on operative time, length of hospital stay, and blood loss. Oncological outcomes, including local recurrence, the number of harvested lymph nodes (LN) and distal resection margin showed no significant distinction among both groups, while the positive circumferential resection margin (CRM) (RR = 0.67, 95% CI: 0.49-0.91, P = 0.01) was lower in the RARS group. RARS demonstrated a significantly higher rate of total mesorectal excision (TME) (RR = 1.07, 95% CI: 1.01-1.14, P = 0.03). CONCLUSION: RARS is safe and feasible for rectal cancer patients and may be superior or equivalent to Laparoscopic-assisted rectal surgery, but high-standard, large-scale trials are required to determine the best approach.

Nested Randomized Controlled Trials in Large Databases: An Opportunity for Inflammatory Bowel Disease?

Although randomized controlled trials (RCTs) are the gold standard for investigating the efficacy and safety of interventions, they present major operational challenges due to their complexity, time-consuming nature, and high costs. To address some of these difficulties, RCTs nested in cohorts (RCTsNC) have been developed to enable patient enrolment and randomization from existing databases. RCTsNC is an emerging trial design, which has been successfully utilized across several medical disciplines but not inflammatory bowel disease (IBD). This narrative review outlines the principles of RCTsNC and discusses the numerous advantages it affords for IBD, including harnessing longer-term longitudinal data for safety and efficacy assessment, and enhanced recruitment and follow up processes. Leveraging pre-existing cohorts and their organizational structures improves patient acceptance and is more economical compared to traditional randomized trials. Observational data for IBD, derived from research (cohort and case-control studies) and non-research sources (electronic health records and registries), provides access to comprehensive records for a large number of IBD patients. It permits researchers to address knowledge gaps in IBD where traditional RCTs have had a limited role, such as specific sub-populations typically excluded from pivotal trials, or assessing the effect of environmental exposures on disease course. This review also details caveats of this study design that include the risk of selection bias and constraints related to comparisons with placebo. In conclusion, RCTsNC offers a promising opportunity IBD research given the challenges of the current IBD RCT landscape.