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A systematic review and meta-analysis to estimate the global prevalence of leptospirosis in sheep.

Leptospirosis in sheep is a zoonotic concern considering sheep may act as potential reservoirs for Leptospira spp. infection to humans. This study aimed to estimate the pooled prevalence of leptospirosis in sheep worldwide. A comprehensive literature search was conducted across databases following PRISMA guidelines. Meta-analyses were performed using a random effect model in R software (version 4.3.1) to calculate pooled prevalence with 95% confidence intervals (CI). Subgroup analyses were performed based on prevalence types, diagnostic methods and continental regions to explore sources of heterogeneity. A total of 138 studies comprising 54,174 samples and 10,299 positive detections were included in this study. The global pooled prevalence of leptospirosis in sheep was 15.69% (95% CI: 12.69-19.25) with overall heterogeneity (I2) 98%. The prediction interval ranged from 1.09% to 75.91%, indicating wide inter-study variability. The seroprevalence was 16.16% (95% CI: 12.91-20.04) and infection prevalence was 12.98% (95% CI: 8.07-20.22), showing no significant difference (P&#xa0;=&#xa0;0.40). In addition, the prevalence of leptospirosis in sheep differed significantly across diagnostic methods and continents (P&#xa0;<&#xa0;0.01), indicating substantial variation influenced by both methodological and geographical factors. The funnel plot revealed marked asymmetry, suggesting potential publication bias which was confirmed by Egger's regression test (P&#xa0;<&#xa0;0.01). In conclusion, leptospirosis is widely prevalent in sheep globally, with marked geographical and methodological heterogeneity. These findings highlight the epidemiological importance of sheep in leptospirosis transmission and underscore the need for improved surveillance, standardized diagnostic approaches, and targeted control strategies within a One Health framework.

Animals

Suicidality risk of cancer caregivers: a systematic review and meta-analysis of observational studies.

BACKGROUND: The increase in the number of global cancer cases is expected to lead to a greater caregiving burden. However, few studies have investigated the risk of suicidality among cancer caregivers. OBJECTIVE: The aim of this systematic review was to explore the risk of suicidality among cancer caregivers. METHODS: For this systematic review, a comprehensive search of the PubMed, Embase, Cochrane, Web of Science databases, PsycINFO and Scopus databases was conducted from inception to 16 July 2025. A meta-analysis was performed to determine the odds ratios (ORs) for case-control and cross-sectional studies and the adjusted hazard ratios (aHRs) for cohort studies. RESULTS: Seven studies were included (four cohort studies, one case-control study and two cross-sectional studies), and 638,188 study subjects and 4,203,957 nonexposed subjects. The meta-analyses revealed that the ORs was 1.91 (95% confidence interval [CI]: 1.46-2.49) in the case-control study, cross-sectional studies, and one cohort study which reported ORs, and the aHRs was 1.32 (95% CI: 1.16-1.50) in the three cohort studies. Caregivers of patients with highly aggressive cancers had a greater risk of suicidality (aHR = 1.66; 95% CI: 1.48-1.86). Within the first 7&#x2009;years following a patient's cancer diagnosis, the risk of suicidality among caregivers remained elevated (aHR = 1.42; 95% CI: 1.04-1.94). CONCLUSION: The results indicate the need for both clinical and societal awareness to reduce the risk of suicidality among cancer caregivers, especially those with highly aggressive cancers. TRIAL REGISTRATION: Registered prospectively in PROSPERO (https://www.crd.york.ac.uk/prospero/) with the registration number (PROSPERO CRD420251011926) and date of registration(15/03/2025).

Humans

HYPNOSA: Study protocol for a prospective observational cohort of patients with obstructive sleep apnea.

BACKGROUND: Obstructive Sleep Apnea (OSA) is a common chronic disease that affects more than 20% of the adult population. One of the most frequent and characteristic symptoms of OSA is excessive daytime sleepiness (EDS). This symptom is typically treated in patients with OSA with the application of continuous positive airway pressure (CPAP), the gold-standard treatment for this disease. In some patients who are adequately treated with CPAP, residual excessive daytime sleepiness (REDS) persists. The prevalence, associations, and outcomes associated with REDS remain poorly understood. METHODS: Multicenter, prospective, observational cohort study including 1000 patients. Participants will undergo a sleep study for the diagnosis of obstructive sleep apnea (OSA), 24-h ambulatory blood pressure monitoring, clinical assessment, quality-of-life questionnaires, Epworth Sleepiness Scale, and collection of biochemical variables and biological samples. Patients with OSA will receive standard care, and those prescribed continuous positive airway pressure (CPAP) will be monitored for treatment adherence. OSA patients will be assessed at baseline and at 6, 12, and 24 months. DISSCUSION: We aim to establish a prospective observational cohort of patients with obstructive sleep apnea (OSA) treated with CPAP, with and without REDS. The HYPNOSA project will create the largest available registry of patients with OSA and REDS using real-world data, providing accurate prevalence estimates and long-term outcomes. Biological samples will be analyzed to assess the role of specific biomarkers. TRIAL REGISTRATION: Registered at ClinicalTrials.gov. Identifer: NCT06514482.

Adult

Approaches to observational study designs and analytical options to evaluate the safety of multi-dose vaccines: a systematic review.

INTRODUCTION: Observational studies require careful considerations when evaluating the safety of multidose vaccines. We reviewed design and analytical approaches in observational studies evaluating the safety of multidose vaccines in the post-licensure phase. METHODS: EMBASE, MEDLINE, Web of Science, and Scopus (2018-2022) were searched for hypothesis-testing studies evaluating the safety of multidose vaccines. Key features from frequently used designs were extracted. RESULTS: Among 123 eligible studies, cohort (46%) and self-controlled case series (SCCS)/self-controlled risk interval (SCRI) (40%) followed by case-control (12%) were the most common designs, and 15% of studies used multiple designs. Among cohort studies evaluating multiple doses, vaccination date (36%) and cohort entry with time-updated exposure status (32%) were frequent approaches used to define time zero. Twenty-eight percent of cohort studies did not report time zero; all but one evaluated COVID-19 vaccine effect on post-delivery and fertility-related outcomes. For SCCS/SCRI, 64% of studies accounted for event-dependent exposures, mainly by including pre-exposure periods (53%) and modified SCCS model (48%), while 20% employed multiple correction strategies. Among studies using multiple designs, 68% reached consistent conclusions. CONCLUSIONS: SCCS/SCRI and cohort designs dominate multidose vaccine safety studies. Clear reporting on time zero in pregnancy and fertility-related cohort studies, and on addressing event-dependent exposures in SCCS/SCRI studies is needed, along with guidance on interpreting results from multiple designs.

Humans

IgA Vasculitis with necrotizing arteritis: a multicenter retrospective study from the French Vasculitis Study Group and systematic review of the literature.

IgA vasculitis (IgAV) primarily affects small vessels, but rare cases with necrotizing arteritis (NA) raise questions about overlap with polyarteritis nodosa (PAN). To characterize IgAV with necrotizing arteritis (IgAV-NA) and compare its phenotype with classical IgAV and PAN. We performed a multicenter retrospective study combined with a systematic literature review (1990-2025). Patients fulfilled EULAR/PRINTO/PRES IgAV criteria, had pathological or imaging evidence of NA in small or medium arteries, and were ANCA-negative. Thirty patients were included (7 from databases, 23 from the literature). NA was confirmed by biopsy (n&#x2009;=&#x2009;16) or vascular imaging (n&#x2009;=&#x2009;14). Clinical features, treatments, remission, and mortality were compared with 257 adult IgAV and 196 PAN patients. Median age was 54.5 years. IgAV-NA was characterized by severe manifestations, including gastrointestinal bleeding, perforation, surgical abdomen, neuropathy, pancreatitis, and livedo. Compared with classical IgAV, IgAV-NA showed significantly higher rates of multi-organ involvement and mortality. Compared with PAN, IgAV-NA shared vascular complications but had less fever and neuropathy. Despite arterial involvement, patients did not fulfil PAN criteria. IgAV-NA represents a rare, severe IgAV phenotype with life-threatening complications rather than an IgAV-PAN overlap. Severe or atypical IgAV presentations should prompt vascular imaging and intensified immunosuppression.

Humans

The relationship between composite dietary antioxidant index and odds of depression: A systematic review and dose-response meta-analysis of observational studies.

BACKGROUND: Recently, the association between the composite dietary antioxidant index (CDAI) score and depression has received special attention from researchers. However, this possible association has not been comprehensively examined. Thus, the present study aims to comprehensively assess the relationship between CDAI score and depression odds. METHODS: A thorough literature search was performed using Scopus, PubMed, and Web of Science up to November 2025. Observational studies assessing the relationship between CDAI score and depression odds were included. The odds ratios (ORs) and their 95% confidence intervals (CIs) reported in each study were extracted, and a pooled effect size was calculated using a random-effects model with inverse-variance weighting. RESULTS: Four observational studies were included in the current systematic review and meta-analysis. The pooled effect size indicated that a higher CDAI score was associated with lower odds of depression (OR:0.62; 95%CI: 0.51-0.76, I2&#xa0;=&#xa0;48.5%; P-value&#xa0;=&#xa0;0.121). In an exploratory linear dose-response analysis based on two eligible studies, no significant association was observed between a one-unit increase in CDAI score and the odds of depression (OR&#xa0;=&#xa0;0.96; 95% CI: 0.91-1.02; I2&#xa0;=&#xa0;92.2%; P-value<0.001). Given the limited number of studies and substantial heterogeneity, these findings should be interpreted cautiously. CONCLUSIONS: Our findings suggest that higher CDAI scores, reflecting greater adherence to antioxidant-rich dietary patterns, are associated with lower odds of depression.

Humans

A prospective crossover study comparing ICCS-recommended and Palmer-adjusted filling rates in children with spina bifida.

OBJECTIVE: This study aimed to investigate whether the maximal cystometric capacity (MCC) in children with spina bifida (SB) is indeed lower, as predicted by the Palmer formula, and to evaluate the impact of different bladder filling rates on urodynamic parameters. MATERIALS AND METHODS: This prospective, randomized, two-sequence crossover-controlled study included 70 children aged 3-18 years with spina bifida under regular follow-up. In Group 1, the first two bladder fillings were performed at the ICCS-recommended rate, and the third at 75% of that rate (Palmer formula). In Group 2, the sequence was reversed. Urodynamic parameters, including maximal cystometric capacity (MCC), bladder compliance, detrusor activity, filling pressures, and detrusor leak point pressure (DLPP), were analyzed across fillings. RESULTS: Cystometric bladder capacity was lower during fillings performed at the Palmer-adjusted rate compared with those at the ICCS-recommended rate. The proportion of reduced compliance significantly decreased in Group 1 (p = 0.046) but remained unchanged in Group 2. A significant positive correlation was observed between expected bladder capacity (EBC) and measured MCC in both groups (&#x3c1; &#x2248; 0.5-0.6). The highest correlation and agreement were found in Group 1 during the third filling at the Palmer rate (ICC = 0.606). No significant intra- or intergroup differences were observed in detrusor pressure, end-filling pressure, DLPP, or overactive bladder prevalence. CONCLUSION: Bladder filling rate was associated with differences in both cystometric capacity and bladder compliance in children with spina bifida. Fillings performed according to the Palmer formula (approximately 75% of the ICCS-recommended rate) were associated with capacities that more closely approximated age-expected values and with modest differences in bladder compliance. Conversely, faster filling rates did not produce similar benefits. These findings suggest that slower filling strategies may improve measurement consistency and agreement with expected bladder capacity estimates. However, the magnitude and direct clinical impact of these differences should be interpreted cautiously, particularly in light of the potential influence of sequence-related effects.

Humans

Marginal fit and five-year outcomes of posterior monolithic zirconia restorations: A randomized paired and observational clinical study.

OBJECTIVES: The aim of this study was to evaluate the marginal fit and five-year clinical performance of posterior 5 mol% yttria-partially stabilized zirconia restorations. A randomized paired comparison with lithium disilicate crowns was performed for marginal fit. METHODS: A total of 65 posterior restorations were placed in 38 patients, including 32 zirconia crowns, 17 lithium disilicate crowns, and 16 zirconia partial coverage restorations. In the randomized paired comparison, 17 patients received one lithium disilicate crown and one zirconia crown. Additional zirconia crowns (n=15) and zirconia partial coverage restorations (n=16) were included in a prospective observational cohort. The primary outcome was marginal fit within the randomized cohort. Marginal and internal fit were assessed using the replica technique. Marginal and internal gap values were compared using the Wilcoxon signed-rank test; clinical outcomes were analyzed descriptively, and Kaplan-Meier estimates were calculated for survival and complication-free survival. Clinical performance was assessed using CDA criteria, periodontal parameters, complication recording, and patient-reported outcomes. Clinical examinations were performed at baseline and at 12, 24, 36, 48, and 60 months. RESULTS: Mean marginal gap values at the crown margin were 46 &#xb1;33 &#xb5;m for lithium disilicate crowns and 50 &#xb1;32 &#xb5;m for zirconia crowns (p>0.05). No restoration required replacement, resulting in 100% restoration survival after a median follow-up of 60 months (range: 57-64 months). Most complications were biological or functional, including endodontic, periodontal, occlusal, and proximal-contact-related events. One zirconia partial coverage restoration exhibited a small ceramic fracture managed by polishing. The Kaplan-Meier probability of complication-free survival was 76.4% for zirconia crowns, 66.7% for lithium disilicate crowns, and 87.5% for zirconia partial coverage restorations. CONCLUSIONS: In the randomized paired comparison, 5 mol% yttria-partially stabilized zirconia crowns showed marginal gap values similar to lithium disilicate crowns. All restorations remained in situ during the observation period. Lower complication-free survival was mainly related to biological and functional events and should be interpreted separately from restoration survival. CLINICAL SIGNIFICANCE: Clinical evidence for posterior 5 mol% yttria-partially stabilized zirconia restorations remains limited. This study provides mid-term clinical data on crowns and partial coverage restorations. In the randomized full-crown comparison, marginal fit was similar to that of lithium disilicate crowns, supporting the clinical consideration of monolithic zirconia restorations for posterior teeth.

Humans

A retrospective population-based cohort study to assess outcomes, time to complications and cost of follow-up care following pediatric pyeloplasty in Ontario, Canada (2002-2016).

PURPOSE: Pediatric dismembered pyeloplasty (PP) is the gold standard surgery for uretero-pelvic junction obstruction (UPJO) in children. However, there is no consensus regarding the duration and methods of providing follow-up care after PP. This study aims to assess the rate of redo-interventions following PP and to define the ideal follow-up care following PP. MATERIALS AND METHODS: This is a retrospective population-based cohort study including all PP patients in Ontario between April 2002 and March 2016 using routinely collected data, with a minimum 5-year follow-up. Baseline variables included demographics, surgical approach, laterality and surgeon experience. The primary outcome was time to secondary surgical intervention, including redo PP. Secondary outcomes included costs of follow-up care and rates of early ER visits. Regression analyses were preformed to predict need for secondary intervention 2-years post PP, including independent variables: age, sex, surgical approach and early complication. RESULTS: The study included 1049 patients with a median age of 2 (IQR 0-7) years. Of the 13.6% of patients who had at least one secondary intervention following PP (including 3.8% who underwent a redo PP), 90.2% occurred within 3-years of PP. The median cost/patient of follow up care was $1472 CAD (IQR $292-$31,133). Regression analysis did not reveal any predictors of delayed secondary intervention. CONCLUSIONS: This study demonstrates that over 86% of PP are completed successfully, with a 3.8% rate of redo-PP. The majority of secondary interventions for post-PP complications occur within 3 years post-PP. Variability in duration and cost of follow-up care post- PP should be addressed to minimize costs, and a minimum 3-years follow-up after PP is recommended.

Humans

Associations between prescribed amphetamines and spontaneous cervical artery dissection: a matched case-control study.

AIMS: To assess whether prescribed amphetamines are associated with spontaneous cervical artery dissection (sCeAD), an important cause of stroke in young adults. METHODS: We conducted a retrospective matched case-control study within a large academic health system in Chicago, Illinois. Adults aged 18-85&#xa0;years with incident sCeAD were matched 1:4 to controls without dissection on age, sex, and race/ethnicity. The primary exposure was documented amphetamine prescription. Conditional logistic regression was used to estimate adjusted odds ratios (ORs) controlling for relevant vascular and clinical covariates. Sensitivity analyses included strict matched-strata and inverse probability-weighted models. RESULTS: Among 11,463 individuals, including 2,293 cases and 9,170 controls, amphetamine exposure was associated with higher odds of sCeAD (adjusted OR 1.70, 95% CI 1.18-2.46). Results were unchanged in strictly matched strata (OR 1.70, 95% CI 1.18-2.46) and remained directionally consistent after inverse probability weighting (OR 1.40, 95% CI 1.09-1.79). High-dose amphetamine exposure (&#x2265;30&#xa0;mg/day) had the strongest association (OR 1.96, 95% CI 1.18-3.26), whereas low-dose exposure was not statistically significant. CONCLUSION: Prescribed amphetamines were associated with modestly increased odds of sCeAD. While these findings are observational and hypothesis-generating, they may support a possible association in susceptible patients.

Humans

Association between hepatic steatosis index and female infertility: a cross-sectional study using NHANES 2013-2018.

Female infertility is a major reproductive health concern. Hepatic steatosis index (HSI), a non-invasive marker of liver-related metabolic burden, has not been well studied in relation to infertility across its distribution. We analyzed women aged 20-49 years from three NHANES cycles (2013-2018). HSI was examined as both a continuous variable and in quartiles, and restricted cubic spline models were used to assess potential nonlinearity. Sensitivity analyses using alternative infertility definitions and exploratory interaction analyses were also performed. Among 3,007 women, 416 (13.8%) were classified as having infertility. In the fully adjusted model, women in the highest HSI quartile had higher odds of infertility than those in the lowest quartile (OR 1.66, 95% CI 1.08-2.57; P = 0.031), with a significant trend across quartiles (P for trend = 0.010). Restricted cubic spline analysis showed a nonlinear association between HSI and infertility (P for overall association = 0.005), which was more evident at higher HSI levels. Higher HSI was associated with greater odds of infertility among reproductive-aged women.

Humans

K-wire versus screw fixation in Scarf-Akin osteotomy for hallux valgus: A retrospective cohort study.

BACKGROUND: Retention of metal implants after Scarf-Akin osteotomy (SAO) may cause irritation and psychological discomfort, often necessitating a hardware removal procedure. This study aimed to introduce K-wire fixation, allowing for outpatient removal, and to compare it with screw fixation. METHODS: This retrospective study included 64 patients with hallux valgus, comprising 32 in the K-wire fixation group and 32 in the screw fixation group. Clinical outcomes were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) score, visual analogue scale (VAS), and patient satisfaction. Radiographic parameters included hallux valgus angle(HVA), intermetatarsal angle(IMA), and distal metatarsal articular angle(DMAA). RESULTS: Both groups showed significant clinical and radiographic improvement (P&#x202f;<&#x202f;0.01). No significant between-group differences were observed in the other clinical or radiographic outcomes (P&#x202f;>&#x202f;0.05). Treatment costs were significantly lower in the K-wire group (P&#x202f;<&#x202f;0.001). CONCLUSIONS: K-wire fixation provides clinical and radiographic outcomes comparable to screw fixation, while avoiding the need for an additional procedure to remove the implant. LEVEL OF EVIDENCE: Level III.

Humans

Extreme Temperature and Incident Diabetes Risk Among Middle-Aged and Older Adults in China: A National Longitudinal Cohort Study.

BACKGROUND AND AIMS: The metabolic consequences of extreme temperature exposure in nondiabetic populations remain poorly understood. This study aimed to examine associations between heatwave and coldwave exposure and incident diabetes mellitus (DM) and impaired glucose tolerance (IGT) in middle-aged and older Chinese adults. METHODS: A total of 1803 China Health and Retirement Longitudinal Study participants aged &#x2265;45 years with normoglycemia at baseline were followed from Wave 1 (2011) to Wave 3 (2015). Eighteen extreme-temperature indicators were derived from city-level fifth-generation European Centre for Medium-Range Weather Forecasts atmospheric reanalysis data. Outcomes were classified according to American Diabetes Association criteria. Generalized linear mixed-effects models (GLMMs) were pooled across five imputed datasets, with Bonferroni correction for multiple comparisons (&#x3b1; = 0.0028) and sensitivity analysis adjusting for individual follow-up duration. RESULTS: All nine heatwave indicators showed odds ratios (ORs) < 1.0 for DM and IGT. HT9 (&#x2265;97.5th percentile, &#x2265;4 consecutive days) was the sole Bonferroni-significant result: OR = 0.845 (95% confidence interval [CI]: 0.802-0.890). Coldwave indicators showed no consistent associations. Age significantly modified the HT9 effect (P-interaction = 0.004): adults aged 65-84 showed a stronger inverse association (OR = 0.616) than those aged < 65 (OR = 0.921). CONCLUSION: Prolonged heatwave exposure was consistently associated with reduced diabetes risk, with pronounced age heterogeneity. Replication in larger prospective studies is warranted.

Humans

Association between fruit and vegetable intake and risk of depression: A systematic review and meta-analysis of prospective cohort studies.

Depression is a leading cause of global disability, and identifying modifiable lifestyle factors is a public health priority. We conducted a systematic review and dose-response meta-analysis of prospective cohort studies examining the association between fruit and vegetable intake and incident depression. PubMed, Web of Science, Scopus, Embase, and Google Scholar were searched through November 2025. Data on study characteristics, dietary assessment, outcomes, effect estimates, and covariates were independently extracted by two reviewers. Random-effects models were used to calculate pooled relative risks (RRs), and linear and non-linear dose-response relationships were assessed. Heterogeneity was evaluated using I2, and evidence certainty was rated with GRADE. Thirteen cohorts with 385,449 participants and 26,592 depression cases were included. Highest versus lowest combined fruit and vegetable intake was associated with a 37% lower risk of depression (RR: 0.63; 95% CI: 0.50, 0.80). Each 200&#xa0;g/day increase corresponded to a 16% risk reduction (RR: 0.84; 95% CI: 0.74-0.94). Separate analyses showed that fruit and vegetable intake reduced depression risk by 16% and 12%, respectively, with a non-linear dose-response for vegetables. These findings indicate that higher consumption of fruits and vegetables is associated with lower depression risk, supporting dietary strategies as a potential approach for mental health prevention. However, given the observational nature of the included studies, these results should be interpreted with caution, as residual confounding may partially account for the observed associations. Registration: This study was registered at PROSPERO (CRD420261279998).

Humans

Analyzing salinity tolerance in grass carp (Ctenopharyngodon idella): Insights from genome-wide association study and genomic selection.

Grass carp (Ctenopharyngodon idella) is one of the most widely cultured freshwater fish species globally. However, the expansion of its farming scale faces severe limitation owing to freshwater scarcity; therefore, the development of strains with greater salinity tolerance is key for expanding production using brackish water resources. To investigate the genetic basis of salinity tolerance in grass carp, a genome-wide association study (GWAS) was conducted using 200 individuals representing extreme phenotypes, namely salinity-tolerant and salinity-sensitive groups. In total, 17 single nucleotide polymorphisms (SNPs) related to salinity tolerance were detected, which were distributed across 11 chromosomes. Through gene annotation, 38 candidate genes were obtained from these loci. Enrichment analysis revealed these candidate genes are primarily implicated in key biological processes, including osmotic regulation, energy metabolism, and stress responses. Analyses of different SNP densities revealed that the 5&#xa0;K SNP density panel can balance prediction accuracy and computational efficiency. The BayesA model achieved the highest prediction accuracy under the GWAS_Evenly selection strategy, with substantial reductions in mean absolute error and mean square error. This study reveals the genetic mechanisms of salinity tolerance in grass carp, which might be optimized through genomic selection, and provides insights for selectively breeding new varieties with greater salinity tolerance.

Animals

International study of coronary microvascular angina (iCorMicA): A registry-based diagnostic study and nested randomized trial.

BACKGROUND: Angina is a debilitating condition caused by coronary artery disease and microvascular dysfunction. Following coronary angiography angina and no obstructive coronary arteries is a common outcome, and women are disproportionately affected. The objectives are first, to assess causes of angina in patients undergoing invasive management; and second, to assess effects of coronary function test-guided management on clinical outcomes. METHODS: This is an international, multicenter, prospective, registry-based study and nested, randomized, controlled, triple-blind, and endpoint trial. Participants, community care providers, and outcomes assessors are masked. Consented participants enter the registry. Participants without obstructive coronary artery disease (luminal stenosis <50%, or fractional flow reserve >0.80) are eligible for randomization. Index of microcirculatory resistance (IMR; abnormal &#x2265;25) and coronary flow reserve (CFR; abnormal <2.0; gray zone 2.0-2.5) are measured by bolus thermodilution, and results are disclosed (intervention) or not (control group) to the attending cardiologist. RESULTS: The primary outcome of the registry is the Seattle Angina Questionnaire summary score at baseline described by coronary artery disease status. Secondary outcomes include the prevalence of obstructive coronary artery disease, patient reported outcome measures and clinical outcomes. The primary outcome of the randomized trial is the within-individual change in Seattle Angina Questionnaire summary score at 12-months from baseline. Secondary outcomes include safety, diagnostic accuracy, patient reported outcome measures for quality of life, physical and psychological function, cardiovascular risk, clinical outcomes, health economics and mechanistic biomarkers. The first patient was screened on December 18, 2020 and the last patient was enrolled on June 30, 2026. Forty sites were included in the United Kingdom (n = 35), Republic of Ireland (n = 2), Holland (n = 2), and Poland (n = 1). In total, 1,483 participants were enrolled into the registry of whom 1,047 were randomized and 386 were not randomized (registry-only). CONCLUSION: This international, registry-based clinical trial will provide novel evidence on the natural history of angina and stratified therapy for angina with no obstructive coronary arteries. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/study/NCT04674449. UNIQUE IDENTIFIER: NCT04674449.

Humans