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Efficacy, tolerability, and threshold effect of atropine eye drops for myopia control: A systematic review and dose-response meta-analysis.

Atropine is an emerging therapy for myopia, yet the optimal concentration for prescription remains uncertain. We searched PubMed, Embase, Web of Science, Cochrane Library, World Health Organization International Clinical Trials, and ClinicalTrials.gov registry platforms. We included the randomized clinical trials (RCTs) that compared any dose of atropine against a placebo in myopic children. Among 3566 studies assessed, we identified 33 eligible RCTs involving 6301 children aged 4-18 years, with 10 different concentrations and a mean follow-up time of 19.5&#x202f;&#xb1;&#x202f;12.3 months. A nonlinear relationship was observed between atropine dosage and treatment efficacy (P&#x202f;<&#x202f;0.001). Compared to placebo groups, the mean differences in reducing annual spherical equivalent refraction progression for atropine concentrations of 0.01%, 0.02%, 0.03%, 0.04%, and 0.05% were 0.21 diopters (D) (95% CI, 0.13-0.28), 0.35 D (95% CI, 0.23-0.46), 0.42 D (95% CI, 0.28-0.56), 0.45 D (95% CI, 0.30-0.60), and 0.46 D (95% CI, 0.32-0.61) respectively For higher concentrations, the estimates were 0.49 D (95% CI, 0.34-0.63) for 0.1% and 0.99 D (95% CI, 0.66-1.31) for 1%, although these were based on fewer and smaller trials. Higher doses of atropine were associated with decreased amplitude of accommodation (P&#x202f;=&#x202f;0.02), increased pupil diameters (P&#x202f;=&#x202f;0.01) and a higher frequency of photophobia (P&#x202f;=&#x202f;0.02). Our findings suggest that the increase in treatment efficacy with higher concentrations may plateau beyond a certain range, and that the current practice of increasing atropine concentrations for children who show inadequate responses to lower doses should be confined to a specific concentration range. This analysis is limited by the number, design heterogeneity, and sample sizes of available trials for higher concentrations, and by the frequent lack of pre-intervention refractive history in included studies. Therefore, estimates-particularly for doses exceeding 0.1%-should be interpreted with caution.

Humans

Non-linear predictive modeling and comprehensive meta-analysis of rectal temperature in Santa In&#xea;s sheep: a systematic review of thermal challenges and biometerological trends.

A systematic and bibliometric review, combined with a meta-analysis, was used to adjust an equation for estimating the physiological responses of Santa In&#xea;s sheep subjected to different thermal challenges. The systematic review compiled data on physiological responses and the thermal environment, which were then used in the meta-analysis to adjust regression models. The bibliometric analysis mapped the relationships among studies, highlighting their usefulness in interpreting research findings and biases. Addressing prior methodological critiques, the core of this study involves replacing the linear approach with a non-linear segmented regression model to accurately define the Thermal Neutral Zone (TNZ). The Segmented Regression Model was crucial, establishing the upper limit of the Thermal Neutral Zone (TNZ) at an air temperature (tair) of 34.64&#xa0;&#xb0;C, where trectal begins to increase abruptly. The model, while identifying a biologically significant breakpoint, exhibited a moderate Multiple R-squared of 0.3529, highlighting the high heterogeneity and methodological variability in the current Santa In&#xea;s literature. This non-linear approach offers a biologically superior tool for identifying the onset of thermal distress.

Animals

Pathways of onward HIV disclosure in relationships among young people living with vertically acquired HIV receiving antiretroviral therapy: A qualitative analysis from the BREATHER Plus trial, South Africa.

For young people living with HIV (YPLHIV) navigating their status since birth, managing onward disclosure of a potentially stigmatising condition in relationships is challenging, and may or may not lead to social support, with implications for wellbeing. In a clinical trial setting in KwaZulu-Natal, South Africa, we investigate how young people living with vertically acquired HIV navigate onward disclosure. Data were from the qualitative component of the BREATHER Plus randomised controlled trial evaluating the efficacy, safety and acceptability of short-cycle dolutegravir/tenofovir-based triple antiretroviral therapy (ART) in young people aged 12-19 years. We analyse data on 35 participants receiving ART engaged in clinical trials at the research site: 29 in longitudinal in-depth interviews (IDIs) and 12 across three focus group discussions (FGDs), including 6 in IDIs and FGDs. The Disclosure Processes Model was applied in the thematic analysis. Pre-disclosure was characterised by social assessments of potential confidants. During disclosure, reciprocal vulnerability and partial information-sharing were employed. Post-disclosure processes entailed linear and non-linear feedback trajectories, impacting future disclosures. The findings show that the study cohort of young people receiving ART navigated many bidirectional disclosure pathways to maintain social connections in relationships, and counselling guidelines need to be responsive to this.

Humans

Optimising Exercise Prescription: A Meta-Analysis Examining the Dose Response of Exercise Duration on Cardiorespiratory Fitness Following HIIT and MICT.

BACKGROUND: High-intensity interval training (HIIT) is often promoted as a time-efficient alternative to moderate-intensity continuous training (MICT) for improving cardiorespiratory fitness, yet the duration of HIIT sessions varies considerably across studies. OBJECTIVE: We aimed to characterise the dose-response relationship between exercise session duration and the improvement in cardiorespiratory fitness for HIIT and MICT. METHODS: A dose-response meta-analysis of randomised controlled trials comparing exercise duration in HIIT and MICT, following Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and registered in PROSPERO (CRD42022335590). Effect sizes were calculated using a random-effects meta-analysis. The primary outcome was maximal oxygen uptake (VO2max). Secondary outcomes included blood pressure, lipid profiles, glucose metabolism markers and body composition measures. A one-stage random-effects dose-response meta-analysis was performed to examine the relationship between exercise duration and adaptations. We searched PubMed and Google Scholar; eligibility criteria for selecting studies were randomised controlled trials in humans, published in English and exercise interventions lasting at least 4&#xa0;weeks. RESULTS: We identified 69 randomised controlled trials (2387 participants). High-intensity interval training elicited greater improvements in VO2max than MICT (d = 0.38, 95% confidence interval 0.27-0.49, p < 0.001). High-intensity interval training demonstrated a non-linear dose-response relationship between exercise session duration and VO2max, with 80% of maximal effect (changes in VO2max = 3.45&#xa0;mL/kg/min) achieved with only ~11&#xa0;min/session (95% confidence interval 9.5-40.2). Moderate-intensity interval training showed a linear dose-response relationship between exercise session duration and VO2max, requiring ~52&#xa0;min/session to achieve 80% of the&#xa0;maximal observed&#xa0;effect (95% confidence interval 30.4-55.8). The dose-response relationship was consistent across populations. High-intensity interval training and MICT had comparable effects in improving cardiometabolic risk factors. CONCLUSIONS: High-intensity interval training demonstrated a non-linear dose response, with 80% of maximal effect on VO2max in ~11&#xa0;min/session, whilst MICT required four to five times longer to reach similar responses. The different types of training had comparable effects on cardiometabolic risk factors.

Journal Article

Exploring the dose-response relationship between prenatal exercise and postpartum depression: A systematic review and meta-analysis of randomized controlled trials.

IMPORTANCE: Postpartum depression (PPD) is a hidden and widespread global public health crisis affecting millions of mothers and infants annually. Prenatal exercise is a potentially accessible nonpharmacological strategy for PPD prevention, but its optimal dose remains uncertain. OBJECTIVE: To explore the dose-response relationship between prenatal exercise and the incidence of PPD through meta-analysis of randomized controlled trials (RCTs). DATA SOURCES: Systematic searches were conducted in PubMed, Embase, Web of Science, and Cochrane Library using MeSH terms and keywords related to "pregnant women," "prenatal exercise," and "postpartum depression," up to June 23, 2025. STUDY SELECTION: RCTs included examined prenatal exercise interventions in pregnant women without a history of depression, with PPD incidence reported using validated depression scales (such as EPDS, CES-D). Non-RCT studies, duplicate publications, and studies with insufficient data were excluded. DATA EXTRACTION AND SYNTHESIS: Two researchers independently extracted data according to the PRISMA guidelines. A random-effects model was used to pool odds ratios (OR) and their 95% confidence intervals (CI). Linear and nonlinear dose-response models were employed to analyze and evaluate the relationship between exercise dose (measured in METs-min/week) and the incidence of PPD. MAIN OUTCOME(S) AND MEASURE(S): The primary outcome is the incidence of PPD, analyzing its relationship with prenatal exercise dose. RESULTS: Eight RCTs involving 2231 pregnant women were included. The pooled analysis showed that prenatal exercise was associated with a potential reduction in PPD incidence, although the overall effect did not reach statistical significance (OR=0.58, 95% CI [0.33, 1.02]). In dose-stratified analysis, exercise doses &#x2265;500 METs-min/week were associated with significantly lower PPD incidence (OR=0.44, 95% CI [0.24, 0.78]). Subgroup analyses suggested trends toward greater benefits among women aged &#x2265;30 years and those initiating exercise between 14 and 28 weeks of gestation; however, subgroup differences did not reach statistical significance. The linear dose-response trend did not reach statistical significance (p = 0.0533), and neither the overall spline association (p = 0.1704) nor the test for nonlinearity (p = 0.6361) was statistically significant. CONCLUSIONS AND RELEVANCE: Prenatal exercise may be associated with a lower risk of PPD, but the overall pooled effect did not reach statistical significance. Findings concerning &#x2265;500 METs-min/week and the apparent flattening of the dose-response curve should be considered exploratory and require confirmation in larger trials.

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

Gout and allopurinol adherence in newly diagnosed patients and the risk of fractures: a nationwide cohort study.

INTRODUCTION / OBJECTIVES: The association between gout and fractures remains controversial due to the competing effects of uric acid's antioxidant properties and gout-induced chronic inflammation. Our study aimed to evaluate the risk of fractures in newly diagnosed gout patients and to analyze the impact of Allopurinol medication adherence on this risk. METHODS: This nationwide cohort study utilized the National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS) database (2002-2019). We identified 4,107 patients newly diagnosed with gout who remained on continuous allopurinol therapy during the 24-month medication assessment period and matched them 1:3 with 12,321 non-gout controls using propensity score matching. Allopurinol adherence was assessed via the Medication Possession Ratio (MPR) over a 24-month period and categorized into three groups: MPR&#x2009;<&#x2009;0.3, 0.3&#x2009;&#x2264;&#x2009;MPR&#x2009;<&#x2009;0.8, and MPR&#x2009;&#x2265;&#x2009;0.8. Multivariable Cox proportional hazards regression was used to calculate adjusted hazard ratios (aHR) and 95% confidence intervals (CI) for fractures (vertebral, hip, and distal radius). RESULTS: Gout patients demonstrated a significantly higher risk of overall fractures compared to the non-gout group (aHR 5.52; 95% CI 4.19-7.26). A significant inverse linear relationship was observed between allopurinol adherence and fracture risk (P for trend&#x2009;<&#x2009;.001). The risk was highest in the low-adherence group (MPR&#x2009;<&#x2009;0.3; aHR 5.91; 95% CI 4.40-7.93) and relatively lower in the high-adherence group (MPR&#x2009;&#x2265;&#x2009;0.8; aHR 4.77; 95% CI 2.94-7.72). Consistent trends were observed for vertebral (aHR 5.68) and hip (aHR 4.22) fractures. These associations remained consistent across all subgroups, including age, sex, and comorbidities. CONCLUSION: Newly diagnosed gout is associated with a substantially increased risk of fractures. Higher adherence to Allopurinol therapy is correlated with a significant reduction in this risk, suggesting that consistent urate-lowering therapy may mitigate gout-related bone fragility. Key Points &#x2022; Newly diagnosed gout patients have a significantly higher risk of major osteoporotic fractures compared to the non-gout population. &#x2022; A significant inverse linear relationship exists between Allopurinol adherence and fracture risk, with the highest adherence group (MPR &#x2265; 0.8) showing a relatively lower risk. &#x2022; Consistent urate-lowering therapy (ULT) may mitigate bone fragility in gout patients by reducing systemic inflammatory burden caused by urate crystal deposition.

Humans

Comparing trajectories of cognitive functioning in treatment-resistant and non-resistant depression: a multicentre linear mixed-effects analysis.

BACKGROUND: Impaired cognitive functioning is a severe symptom in major depressive disorder (MDD). Recent evidence suggests it may be a central characteristic in its treatment resistant form (TRD), potentially constituting a clinical marker for treatment resistance and a target amenable to intervention. To date, cognitive functioning in TRD remains poorly understood and longitudinal investigations are scarce. METHODS: This observational prospective cohort study, including 320 patients diagnosed with MDD from the multicentre PROMPT study, examined differences in cognitive functioning between 118 TRD and 202 non-TRD patients over a period of twelve weeks in a real-world setting, using linear mixed modelling. Patients that failed to respond to at least two prior antidepressants trials at baseline were classified as TRD. RESULTS: TRD patients showed significantly poorer baseline performances than non-TRD patients in attention/processing speed (&#x3b2;&#xa0;=&#xa0;-0.45; 95%CI[-0.70, -0.19]; FDR-p&#xa0;=&#xa0;0.003) and verbal memory (&#x3b2;&#xa0;=&#xa0;-0.45; 95%CI[-0.72, -0.18]; FDR-p&#xa0;=&#xa0;0.003). Significant time &#xd7; group interactions were observed in motor speed and verbal fluency tasks. Post-hoc-analyses revealed stagnation in TRD patients and significant improvement in non-TRD patients. Across all other tasks improvement was observed in both groups, and random effects showed large heterogeneity between patients, indicating notable individual differences in cognitive performances. CONCLUSIONS: The results suggest distinct recovery patters between non-TRD and TRD patients, and diminished functioning in TRD patients at the domain level. However, intact and diminished performances likely occur in both groups, warranting further investigation of cognitive heterogeneity. These short-term findings highlight the need for more comprehensive longitudinal research on cognition in TRD.

Humans

Relationships among mechanisms in psychosocial treatments for chronic pain: mechanism to mechanism lagged effects and relationships with outcomes.

Results suggest that psychosocial treatments for chronic pain work via several mechanisms, and that they often do so to similar degrees and in similar ways. Extant research, however, has focused on individual and/or independent effects of mechanisms on outcomes. Whether successful outcomes are also partly because of sequential and meaningful relationships among and between mechanisms-mechanism-to-mechanism effects-has not been examined. Secondary analyses were conducted of an RCT that compared cognitive therapy, mindfulness-based stress reduction, and behavior therapy to treatment as usual in a sample (N = 521) of people with chronic low back pain. Results of hierarchical linear modeling revealed that (1) Treatment Condition &#xd7; Mechanism interactions predicting changes in other mechanisms were nonsignificant; (2) lagged prior session mechanism changes predicted next session changes in another mechanism; (3) lagged relationships between pain catastrophizing and pain self-efficacy were reciprocal, whereas links between lagged pain catastrophizing and mindfulness changes and lagged pain catastrophizing changes and behavioral activation changes were unidirectional; and (4) individual differences in the strengths of mechanism-to-mechanism relationships predicted pre- to post-treatment changes in outcomes. Results reveal heretofore hidden therapeutic processes that cognitive therapy, mindfulness-based stress reduction, and behavior therapy may share. Namely, that mechanism-to-mechanism lagged effects do indeed emerge beyond mechanism-to-outcome effects. Findings show not only that mechanisms may change in definable sequences relative to each other but that individual differences in the strengths of mechanism-to-mechanism relationships may themselves be predictive of outcomes.

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

Validated UPLC-MS/MS quantification and intracellular PK-PD Modeling of periplocin-related cardiac glycosides in H/R-injured H9c2 cells.

Reliable intracellular quantification is essential for characterizing the target-site disposition and exposure-response relationships of bioactive natural products. In this study, an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the simultaneous determination of periplocin and four related cardiac glycoside metabolites in H9c2 cell lysates. Acceptable linearity, precision, recovery, and stability were achieved for intracellular quantification. Cells were treated with each compound at 50&#xa0;&#x3bc;M, and intracellular concentrations and cell viability were monitored over 48&#xa0;h. In hypoxia/reoxygenation (H/R) -injured cells, the time to maximum intracellular concentration was shortened for all five compounds, indicating altered cellular disposition under injury conditions. Cell viability was improved by all compounds during the observation period. Pharmacokinetic-pharmacodynamic (PK-PD) integration was performed using a sigmoid Emax model, and acceptable model fits were obtained, with Akaike information criterion (AIC) values ranging from 79.22 to 130.46. Low apparent EC50 values were estimated under this single-dose design, whereas the estimated Ke0 values suggested delayed equilibration with the effect compartment. These findings indicate that sustained cytoprotective responses can be produced by periplocin and related metabolic markers in injured cardiomyocytes. This intracellular bioanalytical strategy provides a quantitative approach for linking cellular exposure to pharmacodynamic response and may support further evaluation of periplocin-related cardiac glycosides.

Tandem Mass Spectrometry

Modelling the effects of biological intervention in a dynamical gene network.

Cellular response to environmental and internal signals can be modeled by dynamical gene regulatory networks (GRN). In the literature, three main classes of gene network models can be distinguished: (1) non-quantitative (or data-based) models which do not describe the probability distribution of gene expressions; (2) quantitative models which fully describe the probability distribution of all genes co-expression; and (3) mechanistic models which allow for a causal interpretation of gene interactions. We propose two rigorous frameworks to model gene alteration in a dynamical GRN, depending on whether the network model is quantitative or mechanistic. We explain how these models can be used for design of experiment, or, if additional alteration data are available, for validation purposes or to improve the parameter estimation of the original model. We apply these methods to the Gaussian graphical model, which is quantitative but non-mechanistic, and to mechanistic models of Bayesian networks and penalized linear regression.

Gene Regulatory Networks

Optimal dose and exercise modality to improve HbA1c in older adults with type 2 diabetes mellitus: a systematic review with pairwise, network, and dose-response meta-analyses.

We aimed to compare exercise modalities and evaluate dose-response relationships with glycemic control including continuous aerobic exercise (CAE), resistance training (RT), combined exercise (CE), mind-body exercise (MBE), and high-intensity interval training (HIIT) in older adults with type 2 diabetes mellitus (T2DM). Three databases were searched for randomized controlled trials of exercise interventions in older adults with T2DM reporting glycated hemoglobin (HbA1c). Pairwise, Bayesian network, and dose-response meta-analyses were conducted. Compared with control, HIIT demonstrated the largest estimated reduction (MD&#xa0;=&#xa0;-0.95%; 95% CrI&#xa0;-1.45, -0.49), followed by CE (MD&#xa0;=&#xa0;-0.59%; 95% CrI&#xa0;-0.93, -0.25), CAE (MD&#xa0;=&#xa0;-0.46%; 95% CrI&#xa0;-0.69, -0.24), MBE (MD&#xa0;=&#xa0;-0.42%; 95% CrI&#xa0;-0.76, -0.10), and RT (MD&#xa0;=&#xa0;-0.29%; 95% CrI&#xa0;-0.51, -0.08). Dose-response network meta-analyses suggested a non-linear association between overall exercise dose and HbA1c reduction, with maximal estimated benefits at approximately 704 METs-min/week with the 95% CrI excluding zero between 241 and 920 METs-min/week. HIIT demonstrated the steepest estimated dose-response relationship, but with wider credible intervals. Other exercise modalities showed more gradual dose-response patterns across their estimated effective ranges. Our findings suggest that exercise prescription for older adults with T2DM should be individualized according to exercise modality, dose, and health status.

Humans

Nonviral transposon&#x2011;engineered stem cells characterization: dose&#x2011;dependency between vector copy number and transgene expression.

Genetically engineered stem cells hold substantial promises for advancing regenerative medicine, yet ensuring their genomic safety remains a critical challenge. A key safety concern is vector copy number (VCN), which defines the number of integrated transgene copies per genome. Although ddPCR is used to assess VCN in virally transduced cells, its application in transposon&#x2011;engineered systems is limited. In this study, we extended VCN determination to non&#x2011;viral, transposon&#x2011;engineered stem cells. In alignment with FDA recommendations, the primary objective was to establish a robust and quantitative framework for interim VCN determination at the time of lot release. Specifically, we demonstrate that reliable interim VCN estimates increase in a dose&#x2011;dependent manner with increasing plasmid input. In addition, strong linear correlations between VCN and both EGFP median fluorescence intensity (MFI) and gene&#x2011;of&#x2011;interest (GOI) protein expression validate the accuracy of this framework. Furthermore, comparison of two distinct GOIs revealed gene&#x2011;specific differences in expression efficiency. Together, these findings validate a standardized VCN determination workflow that quantitatively links plasmid dose, genomic integration, and functional transgene expression. This workflow provides a systematic characterization of engineered cells, offering comprehensive information to support downstream risk&#x2011;based analyses to ensure the genomic safety and stability of the final cell product.

Transgenes

Machine learning vs. traditional methods for predicting postoperative cardiac complications after non-cardiac surgery: a systematic review and Bayesian network meta-analysis.

INTRODUCTION: Accurate prediction of peri-operative cardiac complications is critical to optimise pre-operative decision-making. Traditional risk prediction scores, such as the Revised Cardiac Risk Index, show only modest discrimination. Machine learning can model complex, non-linear relationships but their predictive performance compared with traditional scores remains unclear. METHODS: We performed a systematic review and Bayesian network meta-analysis. The primary outcome was postoperative adverse cardiac events following non-cardiac surgery. Prediction models were assessed relative to the Revised Cardiac Risk Index. As many studies evaluated multiple versions of each model type, the highest performing ('best version') and lowest performing ('worst version') results were analysed. Models were ranked using the surface under the cumulative ranking curve (SUCRA). RESULTS: Thirteen studies evaluating 54 models and 927,113 patients were included. Machine learning approaches generally outperformed traditional risk scores. Automated machine learning ranked highest (SUCRA 96.6) showed the greatest improvement in the best version analysis (mean difference (MD) 0.28 (95%CrI 0.16-0.40)) and remained superior in the sensitivity analysis (MD 0.30 (95%CrI 0.14-0.45)). Gradient boosting models showed superior performance over the Revised Cardiac Risk Index across analysis (best version: MD 0.20 (95%CrI 0.14-0.26), worst version: MD 0.18 (95%CrI 0.12-0.25), SUCRA 82.4). The Gupta Perioperative Risk for Myocardial Infarction or Cardiac Arrest score outperformed the Revised Cardiac Risk Index in the best version analysis (MD 0.16 (95%CrI 0.01-0.32)). Between-study heterogeneity was low. None of the included studies externally validated their machine learning models and only six were judged to be at low risk of bias. DISCUSSION: Most machine learning models showed better discrimination than traditional risk scores, with automated machine learning and gradient boosting models ranking highest. However, study quality, calibration reporting and absence of external validation limit immediate clinical adoption. Prospective, multicentre evaluation is required before integration of these models into peri-operative practice.

Humans

The relationship between food intake and outdoor temperature in a longitudinal study: a public health perspective in the context of global warming.

BACKGROUND: Climate change affects human health and nutrition. Rising temperatures may significantly impact diets, but research on their influence on dietary habits in large populations remains limited. OBJECTIVES: We aimed to study the link between outdoor temperature and energy-adjusted food consumption across profiles in a longitudinal study. METHODS: This study included 100,851 participants from the NutriNet-Sant&#xe9; study (2009-2023) with 1,716,046 24-h dietary records linked to daily maximum outdoor temperature at the residence, from the nearest M&#xe9;t&#xe9;o-France station. Associations were analyzed using linear mixed models with interactions tested for sex and 6 socioeconomic profiles (employees, privileged, intermediate, young, disadvantaged, and retirees) derived from clustering. RESULTS: Across all subgroups, higher outdoor temperature was associated with higher consumption of fruits, vegetables, processed meats, sweet products, water, alcoholic beverages, and sugar-sweetened beverages, whereas consumption of red meat, pulses, and dairy products decreased. From 25&#xb0;C to 35&#xb0;C, the increase in alcohol consumption with temperature was more pronounced in males {150 g/d [95% confidence interval (CI): 147 g/d, 153 g/d] to 166 g/d [95% CI: 162 g/d, 171 g/d], +11%} than in females [101 g/d (95% CI: 98 g/d, 103 g/d) to 107 g/d (95% CI: 104 g/d, 109 g/d), +6%]. Across socioeconomic profiles, changes shared similar directions, but some trends were more marked, notably for alcoholic beverages among employees (95% CI: 114 g/d, 130 g/d; +14%) and sugar-sweetened beverages in young (95% CI: 56 g/d, 72 g/d; +29%). Consumption of fruits increased more modestly in the young (95% CI: 227 g/d, 248 g/d; +9%) than in employees (95% CI: 194 g/d, 227 g/d; +17%). These changes, although variable in magnitude, were not accompanied by substantial modifications in energy intake or overall diet quality scores. CONCLUSIONS: These results emphasize the importance of targeted prevention messages when temperatures exceed 25&#xb0;C, especially concerning alcoholic and sugar-sweetened beverages, and offer insight into potential long-term food consumption patterns (beyond seasonal changes) in the context of global warming.

Humans

The Interrelationship between Cadmium, Smoking, and Migraine in the ELSA-Brasil Study.

This study explored the relationship between serum cadmium (Cd), smoking exposure, and migraine in the ELSA-Brasil cohort (2008-2010). The analysis included 2,750 participants whose serum Cd levels were measured using inductively coupled plasma mass spectrometry. Smoking exposure was assessed using self-report data of active smoking and second-hand smoke. Migraine, including definite and probable migraine, was diagnosed according to the International Classification of Headache Disorders, 3rd edition (ICHD-3). Logistic regression was used to estimate the odds of migraine across serum Cd quintiles, using the third quintile as the reference category, while linear regression examined the relationship between smoking exposure and Cd levels. Polynomial contrasts tested linear trends. Participants had a mean (SD) age of 53.2 (9.0) years and 53.1% were women. Migraine prevalence was 29.1% (including probable migraine). Individuals with migraine had slightly higher median serum Cd levels than controls [0.050&#xa0;&#xb5;g/L (IQR 0.035-0.077) vs. 0.048&#xa0;&#xb5;g/L (0.035-0.066); p&#x2009;=&#x2009;0.021], although smoking exposure scores did not differ between groups. Smoking exposure showed a strong positive association with serum Cd concentrations (p-trend&#x2009;<&#x2009;0.001). Participants in the highest Cd quintile had greater odds of migraine [aOR 1.51 (95% CI 1.09-2.08), p&#x2009;=&#x2009;0.011] after adjustment for smoking exposure and sociodemographic and clinical confounders. Sex-stratified analysis yielded even stronger associations among males [aOR 1.84 (95% CI 1.07-3.16), p&#x2009;=&#x2009;0.027]. However, in the sensitivity analysis including definite migraine cases only, this association was no longer significant [aOR: 1.14 (0.71, 1.83), p&#x2009;=&#x2009;0.579]. Main findings suggest that Cd exposure from smoking may contribute to migraine occurrence, particularly in males. However, other sources of Cd that could influence migraine should not be disregarded, and future investigation in this field is warranted.

Cadmium

Source- and Solubility-specific Choline, Gut Microbiota, and Dyslipidemia Risk: Trimethylamine N-oxide-associated and Non-trimethylamine N-oxide-Associated Patterns in a Prospective Cohort Study.

BACKGROUND: Dietary choline, a major precursor of the gut microbial metabolite trimethylamine N-oxide (TMAO), is implicated in dyslipidemia risk; however, source- and form-specific associations and interactions with gut microbiota remain unclear. OBJECTIVES: The aim of this study was to examine longitudinal associations of source- and form-specific dietary choline with plasma TMAO and dyslipidemia and to identify gut microbiota interactions. METHODS: Using data from the China Health and Nutrition Survey (2018-2023), dietary intake was assessed via 3 consecutive 24-h recalls in this prospective cohort study. Two-level generalized linear mixed-effects models were applied in 4828 adults (mean age: 55.9 &#xb1; 12.6 y, 56.6% females) to assess choline-dyslipidemia associations. Choline-TMAO and TMAO-dyslipidemia analyses were conducted in 1091 participants free of dyslipidemia at baseline. Among 7169 adults with gut microbiome data, Least Absolute Selection and Shrinkage Operator and logistic regression identified lipid-associated gut genera; TMAO relationships were examined in a subset of 693 participants. RESULTS: Higher intakes of total [Q4 compared with Q1: odds ratio (OR) = 1.261; 95% confidence interval (CI): 1.007, 1.580], red meat-derived (OR: 1.753; 95% CI: 1.196, 2.568), and lipid-soluble choline (OR: 1.304; 95% CI: 1.047, 1.624) were associated with higher risk of elevated low-density lipoprotein cholesterol (LDL cholesterol), whereas vegetable-derived choline was inversely associated. Egg-derived and lipid-soluble choline were positively associated with plasma TMAO, which was prospectively associated with 5-y incident dyslipidemia (Q4 compared with Q1-OR: 1.620; 95% CI: 1.047, 2.509), elevated LDL cholesterol (Q3 compared with Q1-OR: 2.478; 95% CI: 1.187, 5.174), and hypertriglyceridemia (Q4 compared with Q1-OR: 1.829; 95% CI: 1.028, 3.225). Three TMAO-associated genera were identified: Lachnospiraceae and Phascolarctobacterium as pro-risk taxa and Turicibacter as protective. The adverse LDLcholesterol association of egg-derived choline was observed exclusively in Phascolarctobacterium-enriched individuals. CONCLUSIONS: Dietary choline source and solubility differentially associated with dyslipidemia risk through TMAO-associated and non-TMAO-associated patterns, with gut microbiota as key modulators.

Humans