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PubMed2026

Family-Wise Error Rate Control in Clinical Trials With Overlapping Populations.

We consider clinical trials with multiple, overlapping patient populations that test multiple treatment policies specifically tailored to these populations. Such designs may lead to multiplicity issues, as false statements will affect several populations. For type I error control, often the family-wise error rate (FWER) is controlled, which is the probability to reject at least one true null hypothesis. If the joint distribution of the test statistics is known, the FWER level can be exhausted by determining critical values or adjusted-levels. The adjustment is typically done under the common ANOVA assumptions. However, the performed tests are then only valid under the rather strong assumption of homogeneous null effects, that is, when the null hypothesis applies to all subpopulations and their intersections. We show that under cancelling null effects, when heterogeneous effects cancel out in some or all subpopulations, this procedure does not provide FWER control. We also suggest different alternatives and compare them in terms of FWER control and their power.

Humans↗

PubMed2026

The effectiveness of protective behavioral strategies for reducing alcohol use and alcohol-related harms among adults: A systematic review and meta-analysis of randomized controlled trials.

OBJECTIVES: Excessive alcohol consumption is a major public health concern. Protective behavioral strategies (PBS) are widely incorporated into alcohol interventions, but their effectiveness and role as mechanisms of behavior change remain unclear. This systematic review and meta-analysis evaluated the effects of PBS-based interventions on alcohol consumption, alcohol-related harms, and PBS use. METHODS: PubMed, Embase, Scopus, CINAHL, and ProQuest were searched from inception to December 2025 for randomized controlled trials (RCTs) of adults (≥18 years) delivering PBS as an active intervention component. Random-effects meta-analyses using Hedges' g examined alcohol quantity, drinking frequency, alcohol-related problems, and PBS use. RESULTS: Fifteen RCTs were included, predominantly involving young adults attending U.S. universities. PBS interventions increased protective strategy use (g=0.23, p=0.005 after outlier removal), but alcohol effects were modest: no change in quantity (g=-0.05, p=0.162), small reduction in frequency (g=-0.09, p=0.014), and marginal reduction in problems (g=-0.07, p=0.052; significant in sensitivity analysis). Subgroup findings suggested greater effects at longer follow-up and when PBS was incorporated into multi-component interventions. Evidence supporting PBS as a mechanism of change was limited and inconsistent. CONCLUSIONS: PBS-based interventions produce modest, context-dependent effects on alcohol outcomes. Most evidence comes from young U.S. university students, underscoring the need for studies in more diverse adult populations and further mechanistic research.

Humans↗

PubMed2026

A reanalysis of the Hitachi cohort study evaluating the effectiveness of low-dose CT screening for lung cancer.

The effectiveness of low-dose thoracic computed tomography (CT) screening for lung cancer for non-smokers or light smokers has been unclear. The results of the Hitachi cohort study performed by the conventional multivariable analysis suggested the reduction of lung cancer mortality by thoracic CT screening, but also revealed the lower all-cause mortality in the CT group, which indicated the existence of self-selection bias. Because the background of the subjects in the CT screening group and that in the X-ray screening group were very different, it is critical to adjust appropriately the confounding factors. In this brief report, we describe a re-evaluation of the results of the Hitachi Cohort Study performed by using more flexible methods, propensity score matching and inverse probability weighting.

epidemiology/public health↗

PubMed2026

Effectiveness of grief interventions in underrepresented regions: a systematic review and exploratory meta-analysis.

Background: Most evidence on grief and bereavement interventions originates from Western, Educated, Industrialized, Rich, and Democratic (WEIRD) populations, raising concerns about the generalizability and cultural relevance of existing findings in diverse global contexts. Individuals confronted with the death of a close person, particularly in cases of sudden or potentially traumatic loss, may be at increased risk of adverse psychological and physical health outcomes, highlighting the importance of effective interventions. This study aimed to synthesize evidence on the effectiveness of grief interventions in underrepresented regions.Method: A systematic search of Web of Science, APA PsycInfo, and Scopus, supplemented by manual reference checks, identified randomized controlled trials (RCTs) targeting bereaved individuals in underrepresented regions. Meta-analyses were conducted to estimate overall and subgroup effects based on control type, loss type, and intervention characteristics.Results: Fourteen RCTs comprising 1122 participants were included. Grief interventions demonstrated a significant moderate-to-large effect compared to control conditions (SMD = -0.74, 95% CI [-1.01, -0.47]). Substantial heterogeneity was observed (I² = 77%). No significant subgroup differences were identified.Conclusion: Grief interventions show promising effectiveness across diverse cultural and geographical contexts. However, the limited and heterogeneous evidence base highlights the need for more high-quality RCTs and for the development of culturally sensitive and contextually grounded approaches to mental health care in underrepresented regions.

Humans↗

PubMed2026

Unanticipated Effects of Parental Social Media Use: Guidance for Clinicians.

"Sharenting," the practice of parents posting photographs, videos, and information about their children on social media, has an ever-growing presence in modern society. However, researchers and the public are now recognizing the potential consequences of sharing, including creation of permanent digital footprints, strained familial relationships, and threats to children's safety. Despite this emerging evidence, no U.S. clinical or legal guidelines exist for parents on safe sharing. Visits with behavioral health providers and family physicians can serve as key points for intervention. This column aims to provide clinicians with a better understanding of sharenting and its potential effects on patients and families, guidance on discussing safe online sharing, and a tool for parents and other caregivers to use when deciding whether to post.

Humans↗

PubMed2026

Dissociating behavioral, neural and experiential effects of prefrontal HD-tDCS during conflict resolution.

Inconsistent evidence regarding the cognitive effects of transcranial direct current stimulation (tDCS) highlights the need for more comprehensive approaches to assess its impact. This study aimed to investigate the effects of high-definition tDCS (HD-tDCS) on conflict resolution by combining behavioral, neural, and subjective experience measures. Sixty participants were randomly assigned to anodal, cathodal, or sham HD-tDCS groups and completed a 30-min flanker task. EEG was recorded during the first and last blocks (without stimulation), while stimulation was applied during the intermediate blocks of the task. Using a multidimensional methodological approach including Drift-Diffusion Modeling (DDM), EEG spectral analysis, Lempel-Ziv complexity, and Temporal Experience Tracing (TET), we assessed the cognitive, neural, and phenomenological effects of stimulation. Behavioral results indicated no significant improvements in reaction times or accuracy across the stimulation groups. Similarly, DDM parameters showed no effect of HD-tDCS on latent cognitive processes. However, EEG data revealed a significant reduction in neural complexity in the anodal group during resting-state, suggesting a stabilization or reorganization of neural dynamics. Subjective experience analysis identified two distinct clusters of task-related feelings, though time spent in these experiential states did not differ between groups. Interestingly, sensation of stimulation was significantly higher for anodal stimulation than sham when analyzed as a single dimension. Despite null behavioral effects, this study provides important insights into the neural and subjective responses to HD-tDCS and highlights the value of integrating complementary multidimensional approaches to better characterize brain stimulation effects. These findings contribute to the ongoing debate about the efficacy of tDCS in cognitive enhancement.

Humans↗

PubMed2026

Sodium supplementation strategies in preterm infants: effects on growth, electrolyte balance, and exploratory evidence on neurodevelopment - a systematic review and meta-analysis.

This study evaluated the effects of sodium supplementation on growth, electrolyte balance, and neurodevelopmental outcomes in preterm infants. A systematic review and meta-analysis of published studies were conducted using data from PubMed, Embase, Scopus, and Google Scholar, including randomized controlled trials and observational studies involving infants born before 37 weeks of gestation. Twelve studies comprising more than 2,800 participants were analysed using random-effects models. Sodium supplementation was associated with improved weight gain and a significant reduction in the risk of hyponatremia (RR = 0.28, 95% CI: 0.08-0.96). Pooled incidence estimates indicated hypernatremia (32%) and intraventricular hemorrhage (29%) among supplemented cohorts; however, substantial heterogeneity was observed, and comparative risk estimates were limited. Only one study reported long-term neurodevelopmental follow-up, suggesting potential benefit; however, the available evidence remains limited and hypothesis-generating.These findings suggest that sodium supplementation may support growth and is associated with a lower risk of hyponatremia in preterm infants; however, hypernatremia and other morbidity estimates reported here are largely descriptive frequencies within supplemented cohorts rather than comparative treatment effects, and careful, individualized therapy with close monitoring is needed to minimize potential risks.

Growth outcomes↗

PubMed2026

Effects of exercise snacking on neuromuscular performance in insufficiently active adults: A systematic review and meta-analysis.

OBJECTIVE: To examine the effects of exercise snacking (ES) on neuromuscular performance in insufficiently active adults. METHODS: Six databases were searched from inception to July 17, 2026. Randomized controlled trials and non-randomized studies of interventions involving insufficiently active adults undertaking ES interventions were included. Outcomes were functional performance, muscular strength, and muscular power. A three-level random-effects meta-analysis was performed. Risk of bias was assessed with RoB 2 or ROBINS-I, and certainty of evidence was evaluated using GRADE. RESULTS: Nine studies (13 reports) involving 313 participants were included. In the primary three-level model, ES showed a small positive overall effect on neuromuscular performance (g = 0.37, 95% CI 0.16-0.58, p = 0.001), which remained supported under trial-clustered robust inference with small-sample adjustment. Domain-specific estimates for muscular power/velocity, functional performance, and muscular strength were positive but imprecise and were not statistically supported after small-sample robust adjustment. Robust moderator tests provided no evidence of between-subgroup differences, and the certainty of evidence was low for all outcomes. CONCLUSION: Current low-certainty evidence suggests that ES may produce a small improvement in overall neuromuscular performance. However, domain-specific effects remain uncertain because of the limited number of independent trials, and the overall prediction interval crossed zero, indicating uncertainty across future populations and settings. Larger, preregistered randomized controlled trials are needed to confirm these preliminary findings.

Adult↗

PubMed2026

Effectiveness of kinesiologic tape in the management of postoperative trismus, discomfort, and edema in mandibular fractures: a randomized controlled trial.

OBJECTIVE: This study compared kinesiologic taping (KT) with conventional elastic adhesive bandaging in managing postoperative morbidity following open reduction and internal fixation. STUDY DESIGN: In this prospective, randomized controlled trial conducted at KLE Dr Prabhakar Kore Hospital, 26 patients with unilateral mandibular fractures were allocated into two groups: Group 1 received an elastic adhesive bandage (n = 13) and Group 2 used KT (n = 13). Pain (Visual Analog Scale), facial swelling (standardized linear measurements), and maximum interincisal distance were recorded at baseline and on postoperative Days 2 and 5. Data were analyzed using repeated measures ANOVA and independent t tests (p < .05). RESULTS: The KT group showed significantly lower pain scores and reduced facial edema at Days 2 and 5 compared with controls (P < .05). Trismus improved in both groups without significant intergroup differences. No adverse effects were observed. CONCLUSIONS: KT is a safe and effective adjunct for reducing early postoperative pain and edema after mandibular fracture fixation.

Humans↗

PubMed2026

Assessing the effects of non-invasive transcranial electrical stimulation (tACS and tDCS) on electrophysiological sleep parameters - a systematic review.

Transcranial electrical stimulation (tES), including transcranial direct current stimulation (tDCS) and transcranial alternating current stimulation (tACS), is considered a safe method to modulate cortical activity and endogenous brain oscillations. Given the therapeutic potential of tES across various clinical conditions and the central role of sleep in restoration and memory consolidation, numerous studies have investigated its effects on sleep and sleep-related parameters, yielding inconsistent results. This systematic review provides an up-to-date synthesis of 51 studies assessing the impact of tES on objectively measured electrophysiological sleep outcomes in both healthy individuals and clinical populations. The reviewed studies demonstrate heterogeneous effects, reflecting substantial variability in study designs. Nonetheless, consistent trends emerge, including reduced NREM1 and increases in total sleep time, NREM2, and NREM3 following tES. Moreover, slow-oscillatory tES increased slow-wave power during sleep. Here we show that tES, particularly slow-oscillatory tES, may positively influence sleep architecture and continuity by modulating endogenous brain oscillations. However, due to heterogeneous stimulation protocols, inconsistent findings, the limited number of significant effects and substantial risk of bias the current evidence remains inconclusive. Well-designed, large-scale trials targeting specific sleep outcomes are needed to clarify the therapeutic potential of tES.

Humans↗

PubMed2026

Dispositional optimism and open-label placebo responses in hair cortisol concentrations and psychological distress-A randomized controlled trial.

Open-label placebo (OLP) treatments show beneficial effects on various health-related outcomes, but studies investigating OLP effects on physiological measures remain scarce. This randomized controlled trial examined the effect of a 4-week OLP intervention on psychological distress and hair cortisol concentrations (HCC) in 202 healthy university students preparing for mandatory oral exams and whether dispositional optimism moderates the OLP effects. Participants were randomly assigned to an OLP or control group. Psychological distress was repeatedly assessed via negative affect, test anxiety, and subjective stress. HCC was measured before and within the intervention. Treatment expectations were additionally examined in interaction with optimism. Results show that OLPs significantly reduced psychological distress and HCC compared to the controls. Optimism moderated the OLP effect on HCC, with less optimistic individuals demonstrating the strongest reduction, independent of expectation. Optimism did not moderate OLP effects in psychological distress. However, the OLP effect on psychological distress depended on the three-way interaction of group, optimism, and expectation. The results suggest that OLPs alleviate the psychophysiological impact of a real-life stressor and indicate that optimism and expectation differently shape psychological and physiological OLP responses. These findings are discussed within the framework of the interactionist perspective.

Humans↗

PubMed2026

Effectiveness and implementation of task-sharing cognitive-behavioral interventions for perinatal mental health: A systematic review and meta-analysis.

OBJECTIVE: To evaluate the effectiveness of cognitive-behavioral interventions (CBIs) delivered by nonspecialist providers (NSPs) on perinatal depressive (PND) and anxiety symptoms, and to narratively synthesize their implementation processes and reported implementation outcomes, including acceptability, feasibility, fidelity, cost, and sustainability. METHODS: We systematically searched eight databases from inception to April 8, 2025. Eligible studies were randomised controlled trials (RCTs) assessing CBIs delivered by NSPs for PND and/or anxiety. Two reviewers independently screened, extracted, and assessed trials. Meta-analyses employed random-effects models, with subgroup, sensitivity, meta-regression, and publication bias analyses conducted in Stata 18.0. Implementation processes and outcomes were reported as frequencies or percentages across trials. RESULTS: A total of 47 trials (11, 357 participants) were included in the systematic review, of which 37 trials (8,709 participants) were included for meta-analyses. CBIs were conducted in 12 countries. Nurses and midwives delivered 45% of CBIs. CBIs were associated with reduced PND post-intervention compared with control conditions (standardized mean difference [SMD] -0.49, 95% CI -0.63 to -0.35; I² = 86.8%). Limited evidence from four trials suggested a small sustained effect at 12 months (SMD -0.14, 95% CI -0.27 to -0.02; I² = 26.4%). Reductions in anxiety symptoms were observed immediately post-intervention (SMD, -0.45, 95% CI -0.65 to -0.25; I²=81%), but evidence for longer-term effects was limited. Subgroup analyses confirmed consistent effects across diverse settings, populations, and intervention characteristics. Reporting of implementation processes (e.g., training, supervision, fidelity) was limited, with only 23.4% of trials assessing fidelity and 10.6% evaluating costs. CONCLUSIONS: NSP-delivered CBIs showed beneficial effects on PND and anxiety, with generally encouraging evidence for acceptability and feasibility. However, evidence for sustained effects beyond the immediate post-intervention period remains limited. Future studies should strengthen long-term follow-up and improve reporting of implementation processes and outcomes, particularly in rural and adolescent perinatal populations, to inform scalable and equitable task-sharing models.

Humans↗

PubMed2026

Effect of Perioperative Sucralfate Administration on Pain Control After Tonsillectomy: A Systemic Review and Meta-Analysis.

OBJECTIVES: This study evaluated the efficacy of perioperative intraoral sucralfate in reducing postoperative pain following tonsillectomy through a systematic review and meta-analysis. METHODS: A comprehensive search of PubMed, SCOPUS, Embase, Web of Science, and Cochrane up to September 2025 identified 13 studies comparing perioperative intraoral sucralfate with placebo or no treatment. Outcomes included throat pain, otalgia, swallowing pain, analgesic consumption, and perioperative morbidities. RESULTS: Sucralfate increased the proportion of patients reporting no or mild throat pain and otalgia, improved mucosal healing at 5 to 7 days, and reduced throat pain, swallowing pain, otalgia, analgesic use, and time to resume >50% of a regular diet. No significant differences were observed in postoperative bleeding or nausea/vomiting. CONCLUSION: Perioperative intraoral sucralfate may be an effective adjuvant therapy that improves postoperative pain control, enhances wound healing, reduces analgesic requirements, and facilitates earlier dietary resumption after tonsillectomy.

Humans↗

PubMed2026

The effects of fitspiration TikTok content on body image and mood among young adult women in the U.S.

Fitspiration is an appearance-based form of media that promotes physical fitness and dieting. While not true of all fitspiration media, some forms promote these ideals through visuals of toned, athletic bodies that have become increasingly prevalent on the short-form video platform, TikTok. Although often framed as health-promoting, fitspiration exposure has been associated with upward appearance comparison (i.e., comparison with people perceived as more attractive) and negative effects on body image and mood. The present study investigated the effects of short-form video-based fitspiration on social comparison, appearance importance, appearance anxiety, body dissatisfaction, and negative affect. Using an experimental design, 150 undergraduate women (Mage = 19.28) in the United States were randomly assigned to view a five-minute TikTok compilation of either animal (n = 75) or fitspiration videos (n = 75). Participants completed baseline measures prior to viewing and state-level measures after completing their video set. Results indicated that, relative to control, viewing fitspiration content led to greater social comparison, appearance concerns, feelings of being fat, and sadness. Baseline appearance concerns and depressive symptoms significantly moderated group differences in responses, such that negative fitspiration effects on state-level appearance concerns were found among individuals high but not low in baseline appearance concerns and among individuals low but not high in baseline depressive symptoms. These findings contribute to the growing literature on fitspiration by demonstrating the immediate psychological effects of this content in short-form videos and highlighting the importance of considering individual differences in vulnerability.

Humans↗

PubMed2026

Cost-Effectiveness of Electronic Patient-Reported Outcome Measure Interventions in Cancer: Systematic Review and Parameter Extraction for Economic Modeling.

BACKGROUND: Complex digital interventions that integrate electronic patient-reported outcome measures (ePROM) into clinical practice in cancer have the potential to improve quality of life, increase survival, and reduce health resource use and costs. Such systems can help patients with cancer self-manage chemotherapy symptoms, reduce clinicians' workloads through automated decision support, and resolve problems earlier. However, more research on the cost-effectiveness of ePROM monitoring is needed. OBJECTIVE: This paper comprises two complementary components: (1) a systematic literature review summarizing and evaluating the quantitative and qualitative evidence related to the cost-effectiveness of ePROM monitoring and (2) a health economic model parameter extraction. We also conducted supplementary targeted searches and scoping to provide context to our findings. METHODS: We searched Ovid (including MEDLINE and Embase), Scopus, and the International Health Technology Assessment Database for original English-language papers published on or before March 2025 using search strings that combined terms related to ePROMs, health economics, and cancer/oncology. We included papers reporting health economic-related outcomes for ePROM interventions designed for adult cancer populations and excluded screening tools and conference abstracts. RESULTS: We included 34 publications from 27 unique studies and identified and analyzed 26 ePROM-integrated interventions within these. Most (23/26) of the included interventions explicitly described some form of alert handling and automated decision support based on remote ePROM monitoring. Of the 34 publications, 5 presented full cost-effectiveness analysis results, of which 3 were highly uncertain and lacked clear differences in costs and health outcomes between ePROMs and standard care; conversely, 2 presented strong evidence of cost-effectiveness due to quality-of-life improvements, reduced hospitalizations, and potentially more autonomy in health-related travel (eg, ePROM-monitored patients can drive or walk to the hospital instead of using taxis or ambulances). A further 5 publications reported partial health economic results (eg, cost-consequence and budget impact), of which 1 detected no difference in strategies; in contrast, 4 reported lower health resource use and costs of ePROMs, mainly due to hospitalization reductions. Overall, 12 of the 27 studies included a qualitative component but mostly focused on user experience and design-related themes; only 2 of these addressed economic-specific themes (eg, changes in workflow and resource use due to ePROM implementation and integration), indicating some potential for time saving due to ePROM monitoring. CONCLUSIONS: Some ePROM-integrated interventions demonstrated cost-effectiveness in cancer care, but the evidence base remains limited. Where evidence does exist, cost-effectiveness appears driven by reduced hospitalization and improved quality of life. Qualitative research within the included studies rarely addressed economic questions. We provide a detailed parameter extraction for use in future economic modeling and recommend research priorities, including quantitative mapping of ePROM symptom data onto health resource use patterns, and qualitative work exploring how ePROM implementation affects clinical workloads and patient-perspective costs.

Humans↗

PubMed2026

Effects of short-bout accumulated exercise on postprandial metabolism in adults: A systematic review and meta-analysis.

OBJECTIVE: To systematically evaluate the acute effects of short-bout accumulated exercise (SBAE) interrupting prolonged sedentary behaviour on postprandial glucose, insulin, and triglycerides in adults. METHODS: Systematic searches in PubMed, Web of Science, Embase, Cochrane Library, CINAHL, SPORTDiscus, and CNKI (inception to 10 December 2025) identified randomised crossover trials comparing SBAE (≤10 min/bout, inter-bout interval ≥30 min or adequate recovery) with continuous sedentary behaviour. Outcomes included postprandial glucose, insulin, and triglyceride AUCs. Standardised mean differences (SMD) were pooled using random-effects models. RESULTS: Thirty-one publications reporting data from 29 independent cohorts involving 573 unique participants (mean age 47.8 ± 20.3 years; 47.5% female; mean BMI 29.0 ± 5.1 kg/m²) were included. Compared with continuous sedentary behaviour, SBAE significantly reduced glucose AUC (SMD = -0.53, 95% CI: -0.71 to -0.34, P < 0.001) and insulin AUC (SMD = -0.58, 95% CI: -0.85 to -0.31, P < 0.001), but not triglyceride AUC (SMD = -0.17, 95% CI: -0.48 to 0.15, P = 0.306).Exploratory subgroup analyses showed statistically significant reductions in glucose and insulin for walking and for inter-bout intervals < 60 min, but not for standing alone or intervals ≥ 60 min. A statistically significant insulin-lowering effect was observed in obese individuals. CONCLUSION: SBAE acutely improves postprandial glucose and insulin control. Exploratory subgroup analyses showed statistically significant effects for walking and for inter-bout intervals < 60 min, but these comparisons are observational and no formal interaction test was conducted. These findings provide preliminary evidence for acute SBAE in sedentary populations, though long-term health effects and real-world generalisability require further investigation.

Adult↗

PubMed2026

The effects of cold temperature on the development, microbiome, and transcriptome of the sea anemone Nematostella vectensis.

Thermal conditions impact essentially all aspects of the physiology for ectotherms. While the effects of high temperatures have been widely studied, cold temperature effects on aquatic invertebrates and their microbial communities have been poorly characterized. To determine the diverse effects of exposure to cold temperatures, we assessed acute and long-term impacts of ecologically relevant low temperatures on the development, microbiome, and gene expression of the sea anemone Nematostella vectensis. Two hours post fertilization, embryos were exposed to temperatures from 4°C to 35°C and development rate to the juvenile stage was quantified. We found temperature impacts the development rate of embryos, where lower temperatures extended development time and resulted in mortality below 10°C. For both microbiome and host transcriptomic responses, anemones were held at 20°C, 10°C, and 0°C and compared at 24 hours and 7 days. Extended exposures to colder temperatures caused restructuring of the host-associated microbiome, with the loss of common taxonomic groups from the class Bacteroidia and Bacilli. Lastly, cold stress induced significant changes in gene expression, which were more pronounced at the 10°C than 0°C but showed little change over time in each temperature. Interestingly, expression of genes associated with innate immunity were among the most differentially expressed genes including heat shock proteins and innate immune genes providing a potential host-imposed mechanism to explain the shift in the microbiome. Overall, cold temperatures have broad effects on many facets of this sea anemone and its microbial community and indicate the importance of cold temperature events when characterizing how ectotherms acclimate to thermal variation.

Animals↗

PubMed2026

Effect of Bariatric Surgery on Improvement of Retinal Microvasculature in Patients With Obesity: A Systematic Review and Meta-Analysis.

Obesity is associated with adverse retinal microvascular changes, including narrower central retinal arteriolar equivalent (CRAE), wider central retinal venular equivalent (CRVE) and lower arteriovenous ratio (AVR). Although bariatric surgery improves cardiometabolic risk, its effect on retinal microvascular calibre remains uncertain. We systematically searched the Cochrane Library, PubMed, ScienceDirect and Scopus up to June 2026. Prospective cohort studies reporting CRAE, CRVE or AVR before and after bariatric surgery in patients with obesity were included. Risk of bias was assessed using the Newcastle-Ottawa Scale. Pooled mean differences (MD) with 95% confidence intervals (CI) were calculated using a random-effects model. Eight prospective cohort studies including 283 patients were included. Seven studies contributed to the CRAE and CRVE analyses, and seven contributed to the AVR analysis. Bariatric surgery was associated with a significant increase in CRAE (MD = +4.02 μm, CI [0.26-7.78], p = 0.04). Sensitivity analysis excluding one study showed a stronger and more consistent effect (MD = +5.41 μm, CI [4.59-6.22], p < 0.01). CRVE significantly decreased after surgery (MD = -6.75 μm, CI [-7.42 to -6.07], p < 0.01), while AVR significantly increased (MD = +0.03, CI [0.02-0.05], p < 0.01). Sensitivity analyses suggested that the direction of effect was generally robust, although between-study heterogeneity was present. Bariatric surgery may be associated with favourable retinal microvascular changes in patients with obesity, reflected by increased CRAE and AVR and decreased CRVE.

Humans↗