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PubMed2026

Association between packed red blood cell transfusion and clinical deterioration in neonatal necrotizing enterocolitis: a systematic review and meta-analysis.

BACKGROUND: No systematic review has evaluated the existing evidence regarding the association between packed red blood cell (pRBC) transfusion and clinical worsening of necrotizing enterocolitis (NEC) in neonates. This systematic review and meta-analysis was conducted to address this knowledge gap. MATERIALS AND METHODS: We searched the Cochrane Library, EBSCO, Embase, Web of Science, Google Scholar, and PubMed for studies on pRBC transfusion and NEC published before May 10, 2025. Relevant articles were selected through title, abstract, and full-text screening. English-language case-control studies or cohort studies, or randomized controlled trials involving newborns with NEC that compared pRBC transfusion with no transfusion and reported changes in NEC clinical status were included. Review articles, systematic reviews, case reports, editorials, animal studies, duplicate publications, and studies with incomplete data were excluded. RESULTS: Five studies involving 971 neonates with NEC were included. The pooled analysis demonstrated a potential association between pRBC transfusion and clinical deterioration of NEC in neonates (odds ratio: 6.05, 95% confidence interval: 3.02-12.14). CONCLUSIONS: pRBC transfusion was associated with an exacerbation of NEC in neonates. However, these findings should be interpreted cautiously because of the small number of eligible studies included in this meta-analysis, and future large-scale, well-designed studies are needed to confirm the observed association.

Humans↗

PubMed2026

Hysteroscopic platelet-rich plasma and medically assisted reproduction outcomes: a systematic review and SWOT analysis.

BACKGROUND: Platelet-rich plasma (PRP) has been proposed as an adjuvant treatment in reproductive medicine. While most evidence refers to blind intrauterine instillation, subendometrial administration under hysteroscopic guidance allows targeted delivery under direct visualisation. This systematic review aimed to synthesise the available evidence on hysteroscopic PRP administration and its impact on clinical medically assisted reproduction (MAR) outcomes. METHODS: A systematic search was conducted from inception to December 2025 across major databases. Studies were included if they evaluated hysteroscopic PRP administration in women undergoing MAR, comparing reproductive outcomes between treated and control groups. RESULTS: Out of 142 records, 3 studies met the inclusion criteria. Study populations were heterogeneous and included women with refractory thin endometrium and/or a history of implantation failure. Hysteroscopic PRP administration protocols varied in timing, technique, and dosage. In a prospective case-control study, hysteroscopic intraendometrial PRP injection at a depth of 2-3 mm in the four uterine walls, using an ovum aspiration needle, on days 11-13 of the cycle prior to euploid frozen embryo transfer (ET), was associated with higher implantation (IR), clinical pregnancy (CPR), and live birth rates (LBR) compared with standard therapy. Conversely, no significant differences in CPR, miscarriage rate, or LBR were observed in an observational study evaluating a single intraendometrial PRP injection (35-40 mL, 2-3 mm depth), administered via endoscopic needle on days 6-8 of the menstrual cycle preceding frozen ET, alone or after electrical impulse therapy. A randomised controlled trial in women undergoing intrauterine insemination reported a significant improvement in CPR following hysteroscopic subendometrial PRP instillation in the four uterine walls (1.0 mL each). CONCLUSIONS: Current literature on hysteroscopic PRP administration in reproductive medicine is limited, and robust conclusions cannot yet be drawn. Well-designed randomised controlled trials with standardised protocols are needed to clarify its clinical role.

Humans↗

PubMed2026

Diabetic macular edema and GLP-1 receptor agonist use: a systematic review and meta-analysis.

BACKGROUND: Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are widely used for type II diabetes and obesity because of their cardiometabolic benefits. However, concerns regarding potential ocular adverse effects, particularly diabetic macular edema (DME), have prompted the need to clarify their retinal safety. METHODS: A systematic review and meta-analysis study was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis of Observational Studies in Epidemiology statements (PROSPERO registration: CRD420251176164). MEDLINE (Ovid), EMBASE (Ovid), CENTRAL (Ovid), Web of Science, and PubMed were searched from inception to October 24, 2025. Randomized trials and observational cohort or case-control studies, including individuals with diabetes without baseline DME and exposed to GLP-1RAs were eligible. Two reviewers independently screened studies, extracted data, and assessed risk of bias using ROBINS-I. Certainty of evidence was evaluated using Grading of Recommendations, Assessment, Development, and Evaluation. Random-effects models were used to pool incidence proportions and hazard ratios (HRs). RESULTS: Thirteen retrospective cohort studies (2021-2025) using large real-world databases were included. Across 6 studies, the pooled proportion of incident DME among GLP-1RA users was 0.14 (95% CI: 0.07-0.23; I² = 99.8%). Compared with mixed antihyperglycemic therapies, GLP-1RA use was not associated with increased DME risk (pooled HR: 0.81, 95% CI: 0.52-1.26). GLP-1RAs were associated with a higher relative risk of DME compared with sodium-glucose cotransporter-2 inhibitors (HR: 1.50, 95% CI: 1.17-1.94) but not compared with dipeptidyl peptidase-4 inhibitors (HR: 0.90, 95% CI: 0.69-1.19). Evidence certainty was very low. CONCLUSION: Current low-certainty observational evidence does not support an overall increased risk of DME with GLP-1RA use. Prospective studies are needed to clarify comparative retinal safety.

Humans↗

PubMed2026

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 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↗

PubMed2026

Prenatal exposure to particulate matter (PM) and autism spectrum disorder (ASD) among children: a systematic review and meta-analysis.

The global surge in Autism Spectrum Disorder (ASD) cases, coupled with evidence linking prenatal Particulate Matter (PM) exposure to developmental disruption, demands a comprehensive review to design targeted health interventions. This systematic review and meta-analysis aim to evaluate the strength and consistency of evidence linking prenatal PM exposure to ASD across studies, quantifying this relation to identify actionable environmental risk thresholds. This study employed PRISMA protocols to systematically extract and evaluate evidence from PubMed, Web of Science, Scopus, and ScienceDirect (2010-2024), and screened 4,013 articles to identify qualified case-control and cohort studies (n=29). Data synthesis employed random-effects modeling, accompanied by comprehensive assessment through I2 statistics, Q-tests, funnel plots, Duval and Tweedie's trim-and-fill analysis, and Egger's regression, to ensure validity. A meta-analysis of 16 case-control studies revealed a 34 % increased risk of ASD associated with prenatal PM exposure (pooled OR=1.34; 95 % CI: 1.13-1.54), despite substantial between-study heterogeneity (I2=94.02 %, p<0.001). Publication bias was not significant (Egger's test p value=0.114). Critical trimester-specific analysis uncovered that third-trimester exposure significantly increased ASD risk (OR=1.17; 95 % CI: 1.01-1.34), while first-trimester (OR=1.02; 95 % CI: 0.92-1.11; I2=49.18 %, p<0.10) and second-trimester exposures (OR=1.13; 95 % CI: 0.88-1.38; I2=92.59 %, p<0.001) showed non-significant associations. This review identified prenatal and early life exposure to PM as a risk factor for ASD, indicating a trimester-specific vulnerability. It highlighted the necessity of focused air quality interventions and targeted guidance to reduce prenatal PM exposure to alleviate ASD risk during the critical-window.

Child↗

PubMed2026

Analysis of end-stage renal disease mediated by cuproptosis-related genes.

OBJECTIVE: The complex pathophysiological mechanism of end-stage renal disease (ESRD) has not been fully understood. Cuproptosis is a newly discovered type of programmed cell death. Therefore, this study attempts to clarify the relationship between cuproptosis-related genes (CRGs) and the phenotype of ESRD. MATERIALS AND METHODS: The National Center for Biological Information Gene Expression Omnibus database was applied to obtain the GSE37171 dataset comprising whole-genome microarray analysis of peripheral blood samples. A 3 : 1 case-control design was employed with 75 ESRD patients and 20 healthy controls who were frequency-matched for age, sex, and ethnicity. Based on differentially expressed genes (DEGs) and genes related to cuproptosis, CRGs were identified. Thereafter, we explored two different subpopulations based on the cuproptosis gene and analyzed their expression and immune infiltration. Genes specific to the CRG cluster were identified through the weighted gene co-expression network analysis algorithm, and the best prediction model was determined and verified by four machine learning methods. RESULTS: The study identified 14 differentially expressed CRGs, among which ATP7B, SLC31A1, LIAS, LIPT1, DLD, MTF1, CDKN2A, DBT, and DLST had relatively high expression levels in the ESRD samples. Compared with the control group, expression levels of FDX1, DLAT, PDHA1, PDHB, and GLS were significantly lower in the ESRD group, and CRGs played a key role in the regulation of immune infiltration in ESRD. Two cuproptosis-related molecular clusters were identified in the ESRD samples. Cluster2 was more correlated with the immune infiltration of ESRD. By analyzing the intersection points between CRG cluster and key genes of ESRD, a total of 888 specific DEGs were identified. Functional differences related to specific DEGs were further explored using gene set variation analysis. Five significant genes (SMC5, USP47, USP53, AGA, and DMXL1) were identified by the support vector machine model as key predictors for ESRD disease risk, achieving an area under the curve (AUC) of 1.00 in internal validation. However, external validation in independent cohorts is required prior to clinical application. Individual gene analysis showed an AUC > 0.81 in discriminating ESRD patients from healthy controls, and the expression of all 5 genes in ESRD patients was significantly lower than in the control group. CONCLUSION: This study clarified the relationship between CRGs and the phenotype of ESRD, analyzed their specific roles in the immune microenvironment, and obtained a predictive model, providing new insights for the study of its potential therapeutic targets.

Humans↗

PubMed2026

Assay-dependent variability in peptide biomarker quantification: experimental evidence from renalase in chronic kidney disease.

BACKGROUND: Renalase is a promising biomarker for kidney disease, but published levels vary widely between studies. We hypothesised that variability in commercial enzyme-linked immunosorbent assays (ELISAs) kits and matrix effects (serum vs plasma) drive these inconsistencies. METHODS: Paired serum and plasma samples from 56 participants (28 chronic kidney disease (CKD) stages 2-5, 28 healthy controls) were tested using three commercial renalase ELISAs (BTLAB, Cloud-Clone, EIAab). We assessed intra-assay precision, inter-assay agreement (Spearman's rank correlation and Bland-Altman analysis on log10-transformed values), matrix effects, and associations with estimated glomerular filtration rate (eGFR). Diagnostic performance was evaluated by Receiver operating characteristic (ROC) analysis. RESULTS: Inter-assay renalase concentrations differed markedly (up to orders of magnitude), with weak inter-assay correlations (r ≤ 0.25). Bland-Altman analyses revealed large, systematic biases between kits. Only the BTLAB assay showed consistent serum/plasma agreement, a significant correlation with eGFR (ρ ≈ 0.32-0.42, p < 0.05), and moderate discriminatory performance for CKD in serum (AUC = 0.70) and plasma (AUC = 0.68). Cloud-Clone and EIAab produced divergent results and strong matrix-dependent biases. CONCLUSIONS: Observed variability among commercial ELISA platforms may compromise comparability between studies. Harmonisation, standardised reference materials, and cross-validation are necessary before renalase assays can be used reliably in clinical practice.

Humans↗

PubMed2026

The Effect of Breastfeeding on Cervical Dysplasias.

OBJECTIVE: This study aimed to investigate the relationship between breastfeeding and precancerous cervical lesions. MATERIALS AND METHODS: A case control study was conducted at a tertiary training and research hospital between September 1 and November 1, 2023. A total of 168 patients who attended the gynecology outpatient clinic and reported their breastfeeding experiences were included. Patients with abnormal cervical cytology formed the study group (n = 37), while patients with normal cytology formed the control group (n = 131). Breastfeeding duration and patterns were compared between groups. RESULTS: The control group had normal smear results. In the study group, 15 patients had high-grade squamous intraepithelial lesions, and 22 patients had low-grade squamous intraepithelial lesions. Human papillomavirus (HPV) was positive in 54.1% of the study group versus 9.2% of the control group. The mean breastfeeding duration was shorter in the study group (9.18 ± 3.43 months) than the control group (23.6 ± 3.35 months; p < 0.05). Most control group patients breastfed for 13-36 months (35.1%), while most study group patients breastfed for <6 months (48.6%; p < 0.05). Shorter breastfeeding (<6 months) and HPV positivity were the strongest predictors of abnormal cytology. Breastfeeding <6 months increased the risk 9.883-fold compared with >36 months, while HPV positivity increased the risk 27.612-fold. CONCLUSION: Breastfeeding and longer breastfeeding duration appear to be associated with a lower risk of cervical intraepithelial neoplasia. Given its multiple health benefits, including prevention of gynecological cancers, promoting breastfeeding through public health policies is strongly recommended. Early recognition and prevention of precancerous lesions remain essential to reducing the risk of cervical cancer.

Humans↗

PubMed2026

Reduced FOXP3 expression and its association with genetic ancestry in neuromyelitis Optica spectrum disorder: a Colombian cohort.

BACKGROUND: Autoimmune disorders are characterized by impaired immune tolerance, largely mediated by CD4⁺ regulatory T cells (Tregs), whose function depends on the transcription factor FOXP3. OBJECTIVES: To compare FOXP3 expression levels between patients with neuromyelitis optica spectrum disorder (NMOSD) and healthy controls from Bogotá, Colombia, and to explore their association with genetic ancestry. METHODS: FOXP3 expression was quantified from peripheral blood mononuclear cells using RNA-based analysis. Genomic ancestry proportions were estimated using ancestry-informative markers. RESULTS: FOXP3 mRNA expression was significantly reduced in NMOSD patients compared with controls (∼2.4-fold decrease in median expression; p = 0.027). Lower FOXP3 mRNA expression was associated with optic neuritis (p = 0.0059), but not with historical or current AQP4-IgG seropositivity. In a sensitivity analysis restricted to patients with documented historical AQP4-IgG seropositivity, the direction of reduced FOXP3 mRNA expression was preserved but did not reach statistical significance. In pre-specified exploratory ancestry-related analyses, African (p = 0.035) and Amerindian ancestry (p = 0.012) were associated with FOXP3 mRNA expression levels. CONCLUSIONS: Reduced FOXP3 mRNA expression in Peripheral Blood Mononuclear Cells (PBMCs) suggests an altered immune regulatory profile in NMOSD, potentially involving mechanisms beyond antibody-mediated immunity. The association between genetic ancestry and FOXP3 mRNA expression suggests that population-specific genetic background may influence immune regulatory pathways. These findings should be interpreted as exploratory and require validation in larger, clinically homogeneous cohorts.

Adolescent↗

PubMed2026

Multiparametric flow cytometry immune profiling of pulmonary and extra-pulmonary tuberculosis reveals distinct blood-based biomarker signatures.

This study investigated immune cell distributions, cell-specific immune markers, and selected biomarker targets in pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB) using multiparametric flow cytometry (MFC). Whole blood was collected from 45 individuals, including healthy controls (HC), EPTB, and PTB patients (n = 15/group). Peripheral blood leukocytes were analysed by MFC to characterize CD4+ and CD8+ T cells, natural killer (NK), invariant NKT (iNKT) and NKT cells, classical (CM), intermediate (IM) and non-classical monocytes (NCM), and activated monocytes (AM). Expression of GBP1, CALCOCO2, IFIT3, SNX10, ARG1, PD-1, and PD-L1 was assessed across these immune subsets. Increased frequencies of NK, NKT, and monocytes were observed in PTB and EPTB compared with HC, while CD4+, CD8+, iNKT, and AM were reduced. Monocyte-to-lymphocyte ratios were incrementally elevated in EPTB and PTB compared with HC. Despite variability of expression within groups, median biomarker fold-change expression changes were found between HC, EPTB and PTB groups; (i) (>2.0FC) for ARG1 in CD4, CD8, CM and AM, for CALCOCO2 in AM, GBP1 in CD8 and NCM, PD-1 in CD4, CD8, NK, IM and AM, PD-L1 in CD4, CD8, iNKT and NKT, NK, IM and AM and SNX10 in CD4, CD8, NCM, IM and AM (ii) (<2.0FC) in TB vs HC for CALCOCO2 in iNKT and NKT, IFIT3 in NCM, PD-1 in NK and NCM, PD-L1 in NCM, IM and AM and SNX10 in AM. Statistical significance was achieved for ARG1 (P = 0.017) in CD4 cells. Our findings highlight distinct immune cell and biomarker signatures in PTB and EPTB.

Humans↗

PubMed2026

Glycaemic burden disrupts innate immunity in TB by modulating CD206 expression and macrophage antimicrobial responses.

Tuberculosis (TB) and diabetes mellitus (DM) represent a growing dual global health burden, with chronic hyperglycaemia recognized as a major modifier of host immunity against Mycobacterium tuberculosis (Mtb). Macrophages, central to pathogen recognition, phagocytosis, antigen presentation, and intracellular killing, may be particularly vulnerable to diabetic metabolic dysregulation. This study evaluated phenotypic and functional macrophage alterations in individuals with pulmonary TB, type 2 DM, TB-DM comorbidity, and healthy controls. Surface receptor expression was analysed by multicolour flow cytometry, while phagocytosis and intracellular bacterial clearance were assessed using FITC-labelled Mtb assays and colony-forming unit enumeration. Hyperglycaemia was associated with reduced CD11b, MARCO, and TLR2 expression alongside upregulation of the mannose receptor CD206, which correlated positively with HbA1c levels, indicating a shift toward a permissive M2-like phenotype. Phagocytic uptake of Mtb was significantly impaired and inversely correlated with HbA1c. Antigen-presenting capacity was selectively compromised, with reduced CD80 and CD86 expression in DM and TB-DM groups, while HLA-DR remained unchanged. Intracellular Mtb killing was markedly diminished in diabetic macrophages. These findings demonstrate that chronic hyperglycaemia profoundly disrupts macrophage innate immunity, contributing to increased TB susceptibility and poor infection control in diabetic populations.

Humans↗

PubMed2026

Variants in the interferon regulatory factor 5 gene confer genetic risk for systemic lupus erythematosus in a Han Chinese population.

BACKGROUND: Interferon regulatory factor 5 (IRF5), integral to interferon signaling pathways, has been identified as a susceptibility locus for systemic lupus erythematosus (SLE). Nevertheless, the relationship between IRF5 variants and SLE risk within the Han Chinese demographic remains inadequately characterized. MATERIALS AND METHODS: Genotyping of two functional single nucleotide variants (SNVs) in IRF5 was conducted in 167 individuals with SLE and 246 healthy controls utilizing sequence-specific primer polymerase chain reaction (PCR-SSP). Chi-square and Fisher's exact tests were employed to assess associations. RESULTS: The rs10954213 variant demonstrated a significant association with SLE susceptibility under the recessive model (GG vs. AG+AA, OR = 2.20, 95% CI: 1.30-3.75, p = 0.003, adjusted p [pc] = 0.030) and homozygous model (GG vs. AA, OR = 2.43, 95% CI: 1.36-4.42, p = 0.003, pc = 0.032). Similarly, the rs2004640 variant was associated with an increased risk of SLE across allelic (T vs. G, OR = 1.66, 95% CI: 1.22-2.26, p = 0.001, pc = 0.011), dominant (TG+TT vs. GG, OR = 1.77, 95% CI: 1.19-2.63, p = 0.005, pc = 0.047), and homozygous models (TT vs. GG, OR = 3.72, 95% CI: 1.58-8.78, p = 0.002, pc = 0.016). Haplotype analysis identified protective haplotype HT1 (A/G, OR = 0.54, 95% CI: 0.41-0.73, p < 0.001) and risk haplotype HT4 (G/T, OR = 2.51, 95% CI: 1.42-4.42, p = 0.001). CONCLUSIONS: These findings indicate that IRF5 gene variants substantially modulate susceptibility to SLE in the Han Chinese population. They hold potential as biomarkers for evaluating SLE risk and offer valuable perspectives into disease pathogenesis.

Adult↗

PubMed2026

Association of ERBB4 and SHBG gene polymorphisms with polycystic ovarian syndrome in South Indian women: a case-control genetic analysis.

INTRODUCTION: Polycystic ovary syndrome (PCOS) is a multifactorial endocrinological disorder with a substantial genetic component. However, the role of genes involved in follicular development and androgen regulation remains incompletely understood, particularly in South Indian populations. This study aimed to evaluate how variations in the ERBB4 and SHBG genes affect PCOS risk. METHODOLOGY: A hospital-based case-control study was conducted among 400 South Indian women, comprising 200 women with PCOS and 200 age-matched healthy controls. Genomic DNA was extracted to study SNPs at ERBB4 (rs2178575 and rs1351592) and SHBG (rs1799941 and rs727428) using ARMS-PCR genotyping. The study compared genotype and allele frequencies between cases and controls while assessing their associations with allelic, homozygous, heterozygous, dominant, recessive, and over-dominant genetic models. Genotyping accuracy was confirmed by re-genotyping and Sanger sequencing of a subset of samples. RESULTS: The ERBB4 rs2178575 polymorphism demonstrated a significant association with PCOS, as the AA genotype and A allele combination increased risk across all three genetic models, including homozygous, recessive, and allelic models. The ERBB4 rs1351592 variant was associated with 3-fold higher risk of PCOS in heterozygous and GC carriers. The SHBG rs1799941 polymorphism showed a significant link to PCOS through its effects on heterozygous and allelic states, whereas rs727428 displayed no significant connection due to its monomorphic distribution. CONCLUSION: These findings suggest that polymorphisms in ERBB4 and SHBG may contribute to PCOS susceptibility in South Indian women in a locus- and model-specific manner, revealing the intricate genetic structure that defines this medical condition.

Humans↗

PubMed2026

Sodium Glucose Co-Transporter 2 Inhibitors and Ventricular Arrhythmias in Patients with Type 2 Diabetes: A Systematic Review of Observational Studies.

BACKGROUND: Sodium glucose co-transporter 2 inhibitors (SGLT2i) may exert antiarrhythmic effects, but their association with ventricular arrhythmias remains unclear. OBJECTIVE: We conducted a systematic review to evaluate the association between SGLT2i use and the risk of ventricular arrhythmias, cardiac arrest, and sudden cardiac death compared with other antidiabetic medications or no SGLT2i use among patients with type 2 diabetes mellitus. METHODS: MEDLINE, EMBASE, and CENTRAL were searched for observational studies published between March 2013 and March 2026. Quality was assessed using the Risk of Bias In Non-Randomized Studies of Interventions (ROBINS-I) tool, alongside evaluation of pharmacoepidemiology-specific biases. RESULTS: A total of 17 studies (16 cohort and one nested case-control) were included. Based on ROBINS-I, seven studies had moderate, eight serious, and two critical risks of bias. Eleven studies had at least one pharmacoepidemiology-specific bias. For ventricular arrhythmias, estimates ranged from a protective effect (hazard ratio [HR] 0.20, 95% confidence interval [CI] 0.04-0.97) to a potential increased risk (odds ratio 1.87, 95% CI 0.89-3.95) with SGLT2i use. For cardiac arrest, estimates consistently reported a lower risk with estimates that ranged from HR 0.63 (95% CI 0.59-0.68) to HR 0.85 (95% CI 0.82-0.88). The only study on sudden cardiac death reported a potential risk reduction (HR 0.62, 95% CI 0.38-1.01). CONCLUSIONS: While the association between SGLT2i and ventricular arrhythmias remains inconsistent, the use of SGLT2i likely reduces cardiac arrest and may reduce sudden cardiac death, suggesting a possible protective effect on ventricular arrhythmias among patients with type 2 diabetes.

Journal Article↗

PubMed2026

Polygenic risk scores in major depressive disorder: A systematic review across diagnostic, treatment, course/severity, and subtype domains.

BACKGROUND: Major depressive disorder (MDD) is heterogeneous across diagnostic, treatment-related, course/severity, and subtype domains. Polygenic risk score (PRS) studies have examined these domains, but differences in PRS sources, samples, methods, and endpoint definitions have fragmented the evidence. We synthesised findings and examined potential contributors to heterogeneity. METHODS: PubMed/MEDLINE, Embase, PsycINFO, and Web of Science were searched for studies published from January 2016 through 25 November 2025. Result records were synthesised using SWiM, and certainty was assessed with an adapted GRADE framework. RESULTS: Sixty studies contributed 493 retained records; 450 were descriptively classified as positive, null, or reverse, although records were not independent. Positive findings accounted for 44/56 diagnostic, 61/273 treatment-related, 64/100 course/severity, and 14/21 subtype records. For MDD/depression-derived PRSs and case-control MDD status, all 10 contributing studies showed higher liability in cases (exploratory exact sign test p = 0.002; FDR q = 0.004). The same PRS group showed positive findings for overall depressive symptom severity (14/18), although the study-level test was imprecise (5/5 studies; p = 0.063). Pharmacological response/remission findings for these PRSs were mostly null or directionally mixed (10 positive, 18 null, and 9 reverse). Treatment-resistant depression (TRD) findings differed by operational definition. Atypical and psychotic subtype signals arose mainly from single-study PRS and endpoint contrasts. CONCLUSIONS: PRS evidence was clearest for MDD diagnostic status and showed a tentative pattern for overall symptom burden. Treatment and subtype findings were less consistent or less replicated. Larger, ancestrally diverse studies with standardised endpoints and transparent PRS methods are needed.

Humans↗

PubMed2026

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↗

PubMed2026

Mining Stored-Specimen Studies for Information about Cancer Natural History.

The advent of new multicancer early detection tests and publication of early diagnostic results have generated expectations of clinical benefit from multicancer screening. The clinical benefit of a cancer screening test depends critically on disease natural history, which is typically learned from prospective screening studies. Retrospective studies of stored blood specimens are important in learning about a test's preclinical diagnostic performance but have rarely been used to infer natural history. The extent to which these studies might be harnessed to also learn natural history is discussed in the context of an article in this issue that infers the combined natural history of a range of cancers targeted by a multicancer early detection test using a case-control subsample of specimens from a large cohort study. The critical question concerns the identifiability of key transition rates in multistate models of natural history alongside state-specific sensitivities. The article suggests that these parameters are estimable within a Bayesian framework that leverages prior information about test sensitivity from diagnostic studies. We offer a heuristic discussion of identifiability in this setting and encourage formal study to determine the extent to which models with varying degrees of complexity may be learned from stored-specimen studies. See related article by Dai et al., p. 1535.

Humans↗

PubMed2026

Prevalence of unruptured intracranial aneurysms according to comorbidities, risk factors, country, and time period: a systematic review and meta-analysis.

BACKGROUND: The incidence of aneurysmal subarachnoid haemorrhage declined between 1980 and 2010, which coincided with a decline in smoking and prevalence of hypertension. We aimed to investigate whether the decrease in subarachnoid haemorrhage incidence is paralleled by declines in unruptured intracranial aneurysm (UIA) prevalence. METHODS: For this systematic review and meta-analysis, we searched Embase, PubMed, and Web of Science for articles published in any language from Jan 1, 2011 to Dec 31, 2025, and reassessed 68 articles published before March 1, 2011 from a 2011 systematic review and meta-analysis. Articles were eligible for inclusion if they used a cross-sectional or case-control design and provided the crude number of participants and those with UIA. We only included studies reporting numbers of UIA separately from ruptured aneurysms and with ten or more patients. Summary data were independently extracted by JD with AZ or CB and conflicts were resolved by GJER. The primary outcome was proportion of participants with UIA. Relative to a hypothetical reference population (mean age 50 years, 50% women, and no comorbidities), age and/or sex-adjusted prevalence ratios (PRs) for regions, comorbidities, and risk ratios (RRs) for female sex, smoking, and hypertension were estimated using generalised linear mixed models. A time trend analysis was done by binomial meta regression using the mid-year of data acquisition. We assessed the certainty of evidence using GRADE. The study was registered with PROSPERO, number CRD420261296728. FINDINGS: Our search screened 4708 studies. 67 reassessed and 95 newly identified articles, reporting on 316 131 participants and 11 822 people with UIAs, were included in our meta-analysis. In the reference population, the estimated prevalence of UIAs was 3·9% (95% CI 3·0-5·1). The prevalence of UIAs in individuals with atherosclerosis was 5·5% (4·7-6·4; 2229 of 40970 participants) and the adjusted PR was 1·3 (95% CI 0·8-2·0) compared with the reference population. For positive family history of aneurysmal subarachnoid haemorrhage (aSAH) or UIA, the UIA prevalence was 7·9% (5·6-11·1; 412 of 4252 participants) and the adjusted PR was 2·4 (0·5-11·2). For connective-tissue disorder, the UIA prevalence was 10·3% (6·5-16·0; 94 of 879 participants) and the adjusted PR was 3·9 (2·0-7·6). For autosomal dominant polycystic kidney disease (ADPKD), the UIA prevalence was 12·8% (9·2-17·6; 293 of 1990 participants) and the adjusted PR was 4·4 (1·5-12·6). RRs were for current smoking 1·4 (1·2-1·6; 798 of 27911 participants), for having hypertension 1·6 (1·5-1·7, 4043 of 83053 participants), and for female sex 1·9 (1·8-2·0; 3415 of 65020 women and 2122 of 76130 men). In studies on healthy individuals with MR angiography or CT angiography as imaging modality, the prevalence in 2016-2022 was 6·6% (6·3-6·8; 2904 of 41191 participants). The adjusted PR was 1·8 (1·1-2·8) for 2016-2022 versus 2002-2015. Prevalence of UIAs of 5 mm or larger was 0·7% (0·6-0·8) in 2002-2015 and 1·4% (1·0-1·9) in 2016-2022. The UIA prevalence did not differ between countries. τ2 showed significant heterogeneity between studies. The certainty of the evidence ranged from very low to moderate. INTERPRETATION: Prevalence of UIA is increasing, particularly over the past two decades. This increase is only in part explained by improved detection of small UIAs and an ageing population, and other factors-such as environmental-are likely involved. Alongside patients with ADPKD and a positive family history of aSAH, patients with connective-tissue disorders had a higher prevalence of UIA than the reference population. Our findings warrant further investigation into the potential benefit of personalised screening and management strategies in groups at high risk for having UIAs. FUNDING: None.

Humans↗