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Impact of the French top-down management of the COVID-19 pandemic on residential care homes
No full textChapitre 6International audienc
Widening exposome exploration with a novel multiplexed HRMS analytical approach : a case study on pesticide internal exposure
No full textInternational audienceIntroduction : Human exposure to food and environmental chemical contaminants including pesticides is generally assessed by indirect (e.g. questionnaires) and/or targeted methods focusing on a limited number of selected compounds. These methods often require a large amount of sample for analyses as complete and sensitive as possible. Thus, human health risks associated with multi-exposure to complex mixtures currently remain underexplored. Based on the exposomics concept and previous studies (1,2), we propose an innovative global chemical profiling approach integrating three complementary HRMS platforms (LC-HILIC-HRMS, LC-C18-HRMS and GC-HRMS), for capturing an extended range of contaminants and related metabolites from a unique urine sample.Methods : Fractionation of reduced-volume urine samples (0.5 mL) was preformed using Strata-X® SPE cartridges. HRMS experiments were conducted on GC-Orbitrap q-Exactive (GC-MS), Sciex X-500-R Q-ToF (C18-LC-MS) and LTQ-Orbitrap XL (HILIC-LC-MS) instruments. Data processing was carried out on both commercial and open source softwares (Trace Finder, W4M, Scannotation, …). A set of 187 standard compounds (parent compounds + metabolites) covering both a large range of molecular weights (72 g/mol1000) from a single sample, provides valuable data for assessing associations with health endpoints for epidemiological studies. Novelty : innovative multiplexed HRMS methodology for wide exposomics from a unique sample. References1 E. L. Jamin et al. Anal. Bioanal. Chem., 2014, 406, 1149-1161.2 N. Bonvallot et al. Sci. Tot. Environ., 2021, 786, 147499.3 T. Moufawad et al. In preparatio
Moderating effects of self-defined sexual orientation on the relation between social factors and depressive symptoms or suicidal ideation among French young adults
No full textInternational audiencePurpose - Disparities in mental health across sexual orientation groups and among young adults have long been discussed. The aim of this cross-sectional study was to investigate the moderating effects of sexual orientation on the associations between social factors and depressive symptoms as well as suicidal ideation in young adults. Methods - The study included 6,337 participants aged 18-25y in 2022 from the French EpiCov cohort. The outcome variables were depressive symptoms and suicidal ideation. Poisson regressions with robust error variance were performed to investigate the associations between social factors and outcomes according to sexual orientation (lesbian, gay, bisexual, other, or not defining themselves according to their sexuality: sexual minority (SM); heterosexual or not wishing to answer: Not belonging to SM (NSM)). Results - The prevalence of depressive symptoms and suicidal ideation was higher in the SM than in the NSM group. Regarding depressive symptoms, significant moderating effects of sexual orientation were observed for female vs male sex (NSM: adjusted Prevalence Ratio (aPR) 1.58[1.28-1.95], SM: aPR 1.03[0.78-1.36]) and age category 22-25y vs 18-21y (NSM: aPR 1.32[1.05-1.67], SM: aPR 0.78[0.59-1.03]). Regarding suicidal ideation, significant moderating effect was observed for not being vs being in a relationship (NSM: aPR 1.55[1.14-2.12], SM: aPR 0.82[0.59-1.13]). Conclusion - In this study conducted in 2022, well-known social risk factors of mental problems do not explain the higher prevalence of depressive symptoms and suicidal ideation among young SM group. Further studies are needed to understand the specific challenges faced by these young people
Enhancing Hydrological Modeling with Bias-Corrected Satellite Weather Data in Data-Scarce Catchments: A Comparative Analysis of SWAT and GR4J Models
No full textInternational audienceHydrological models are widely used to assess climate change effect on water resources at the catchment scale. However, data scarcity is one of the main challenges faced by hydrological modelers especially in developing countries. Remotely sensed and large-scale climatic datasets offer a viable alternative for hydrological modeling. Hence, this study evaluates CFSR-NCEP reanalysis data for discharge simulation using SWAT semi-distributed and GR4J conceptual lumped hydrological models. First, the CFSR-NCEP monthly reanalysis precipitation and temperature were compared to the observed data. Then, the performance of SWAT and GR4J models to simulate monthly discharge using both daily CFSR-NCEP reanalysis data with and without bias correction was compared across different climate conditions. Results indicated that the GR4J model performed well, with an average NSE of 0.89 across calibration and validation periods, indicating its ability to handle low-quality input data. A poor performance of the SWAT model was observed using CFSR-NCEP data without bias correction (NSE < 0.60). Primarily due to biases in meteorological data, and to low quality of spatial data. Bias correction improved both models' performance, with NSEs exceeding 0.78 for SWAT model and 0.91 for GR4J model. Moreover, the stability of models' performances under the three calibration periods shows that SWAT and GR4J models are respectively influenced and not much influenced by the climate of the calibration period. Consequently, GR4J remains valid for climate projection. Our research shows that despite their widespread use, complex physics-based hydrological models such as SWAT are often less performing in data-limited catchments. However, conceptual models prove more performing, providing valuable information for researchers and decision-makers to devise robust quantitative water resource management strategies under these challenging conditions
L'impact du diagnostic de cancer sur la consommation de soins des personnes atteintes d'une sclérose en plaques : une étude multi-pays
No full textInternational audienceBackground and objective(s)Neurological care and disease modifying therapies (DMT) play a vital role in managing multiple sclerosis (MS). Yet, as the MS population is aging, how they are impacted by comorbidity diagnoses, such as cancer, remains uncertain. The objective of this study was to describe the impact of cancer on healthcare use among cancer survivors with MS.Material and MethodsWe performed a multi-country study investigating the impact of cancer on MS-related healthcare use using population-based health administrative data from France and the province of British Columbia (BC) in Canada. Data was available from 01/01/1991 to 31/03/2020 in BC and from 01/01/2009 to 31/12/2021 in France. Cases were defined as persons with MS (PwMS), aged 18 and older, diagnosed with an incident cancer, alive two years after cancer diagnosis. The study period was defined as the three-year period prior to cancer as well as the two-year period after. Each case was matched on period, sex, year of birth, residence, duration of MS and DMT-use to two cancer-free PwMS, defined as controls. The outcomes of interest were (i) neurologist visits rates (ii) MS-hospitalization rates; (iii) MS-specific DMT use proportions. Mixed effect models were used to assess the impact of cancer diagnosis on MS health care use among cases compared to controls and time was modelled using a piecewise linear spline with a knot at the time of cancer diagnosis. The knot allowed to fit two slopes, before and after cancer, which were compared using a slope ratio (SR). The type of mixed effect model used differed according to the outcome: (i) neurologist visits were modelled using a poisson distribution (incidence rate ratio, IRR) (ii) MS-hospitalizations using a zero-inflated poisson distribution (IRR) and (iii) DMT-use using a logistic distribution (odds ratio, OR).ResultsA total of 6,902 pwMS were included as cases (France=4,555; BC=2,347) and matched 2:1 to 13,804 controls (France=9,110; BC=4,694) with a majority of women (France=71.6%; BC=75.9%). Mean cancer age was 58.6±12.5 years in France and 55.9±11.6 years in BC. DMT-use in the 24 to 12 months prior to index date differed greatly between regions, with 38.8% of individuals having received at least one MS-specific DMT in France vs. 9.6% in BC. Over the study period, there was a slightly higher proportion of cases that visited the neurologist compared to controls (France= 78.7% vs 75.6%; BC=72.0% vs 68.7%) with an overall decrease for both groups over time. In BC, both before and after cancer, cases had a slightly higher neurologist visit rate than controls (before: IRR 1.08 [1.01-1.16]; after: 1.08 [1.00-1.16]). However, the IRRs did not differ before and after cancer diagnosis (1.00 [0.91-1.11]). Regarding MS-hospitalizations, both before and after cancer, no difference in MS-hospitalisationrates for cases vs controls was observed (IRR, before: 1.24 [0.65-2.35]; after: 1.49 [0.80-2.76]). IRRs did not differ before and after cancer diagnosis (SR 1.20 [0.74-1,58]). Finally regarding DMT-use, both before and after cancer, no difference was observed between cases and controls (OR; before: 1.30 [0.79-2.16]; after: 0.70 [0.42-1.18]). However, there was weak evidence that the after cancer estimate was lower than the one before cancer (SR 0.54 [0.28-1.03], p=0.06). Results from France were comparable.ConclusionThere was no evidence of a strong impact of cancer on MS-related care amongst cancer survivors with MS, compared to matched pwMS with no cancer
Modélisation du taux en excès avec un terme de fragilité partagée en présence d'hétérogénéité entre clusters et de tables de mortalité inappropriées: un cas d'usage en épidémiologie de la maladie rénale chronique
No full textInternational audienceBackground and objective(s)In chronic-disease epidemiology, researchers may focus on disease-related mortality rather than overall mortality. When cause of death information is unavailable, disease-related mortality can be estimated using the relative survival approach. This method assumes that the observed mortality can be decomposed into mortality due to the disease, the excess mortality, and mortality due to others causes, the expected mortality. In the overall survival framework, a shared frailty is often used as a multiplicative effect on the hazard to account for the between cluster heterogeneity. Recent developments in relative survival methodology have introduced a cluster-level frailty applied only to excess hazard. However, directly translating a frailty model for observed hazard into the relative survival framework would involve a joint shared frailty, meaning that heterogeneity would affect both the excess and the expected hazards. The presence of heterogeneity acting on expected hazard can be due to the use of inappropriate life tables as proxy of the expected mortality. The objective was to propose excess hazard models in the presence of clusters heterogeneity and inappropriate life tables.Material and MethodsTwo shared frailty models accounting for the between cluster heterogeneity acting on expected and excess hazards were developed; one without (M1) and one with (M2) a fixed-correction parameter used to rescale the background mortality. The parameters were estimated using the maximum likelihood method. A large simulation design considered various functions for the baseline excess hazard, various numbers of clusters and sample size, medium and high strengths of the between cluster heterogeneity. The proposed models were also compared with existing cluster-level frailty excess hazard models [1] (M3 & M4). Bias, root mean square errors, empirical coverage rate and Akaike Information Criterion (AIC) were used as performance criterion. Finally, the models were also applied on dialyzed patients from the French Epidemiologic and Information Network in Nephrology (REIN).ResultsOverall, the simulated results were satisfactory and highlighted specific configurations where the proposed models performed best. A large number of clusters and of individuals per cluster is preferable, in order to obtain unbiased estimates of the parameters. Models also performed best when the cluster heterogeneity is lower. The simulations have also shown that using a fixed correction of the background mortality is also not recommended below 5,000 individuals. Moreover, when the simulation design assumed a frailty acting on both hazards, M1 and M2 led to poor performance. The AIC was able to discriminate between the compared models. In the application study, we explored the variations in excess hazard by French départements. M2 was favored by the AIC (M1: 50,752/ M2: 50,739/ M3: 50,753/ M4: 50,745), leading to a smaller standard deviation estimate of the between départements heterogeneity 0.17 [0.14,0.21] and a larger correction parameter of the French life tables 1.83 [1.49,2.25].ConclusionTranslating an overall shared frailty hazard model into its complement in the excess hazard framework provides a new tool to address inappropriates life tables settings in chronic disease epidemiology
Beneath the smoke: Understanding the public health impacts of the Los Angeles urban wildfires
No full textCommentaryInternational audienc
Transformer les villes pour préserver la santé des générations présentes et futures
No full textDossier "'urbanisme au service de la santé"International audienceSelon le Groupe d’experts intergouvernemental sur l’évolution du climat (Giec), il est indispensabled’agir contre le changement climatique tout en protégeant la nature pour garantir un avenirviable. Les zones urbaines, où vivent 55 % de la population mondiale, sont particulièrementvulnérables aux risques climatiques (événements extrêmes, crise systémique) et environnementaux(pollution de l’air, canicule, bruit, etc.). Face à cette situation, il n’y a pas de fatalité : adapterles environnements urbains aux nouveaux enjeux climatiques, réduire le trafic routier, favoriser les mobilités actives – comme la marche à pied ou le vélo –, développer les espaces verts sont autant de stratégies accessibles et efficaces, favorables en matière de climat, de biodiversité et de santé publique.Au total, les collectivités disposent ainsi de leviers d’intervention majeurs pour agir, mais quinécessitent une volonté forte de collaboration multisectorielle afin de transformer littéralementles villes
Updated Multiple Sclerosis Incidence in France, 2011–2021
No full textInternational audienceBackground and objectives:Multiple sclerosis (MS) is a chronic neurological disorder with significant implications for public health as being the first cause of non-traumatic neurological disability in young adults.Although the global prevalence of MS has been increasing, recent temporal trends in incidence remain unclear. We aimed to evaluate current MS incidence trends in France over 11 years using the Système National des Données de Santé (SNDS), a nationwide administrative database covering 99% of the French population. Methods:We utilized a published algorithm that incorporates multiple data sources, including benefits from long-term diseases, specific disease-modifying treatment prescriptions, and hospital discharge, to identify incident MS cases from January 1, 2011 to December 31, 2021. Sex and age-standardized incidence and prevalence were estimated using a "specific" and a "sensitive" definition providing bounds on the evolution of recent incidence. We used multivariable Poisson regression models to estimate temporal trends in incidence rates, calculating incidence rate ratios (IRR) along with corresponding 95% confidence intervals. In a sensitivity analysis, the time lag between past visits to neurologists and the database recording of MS was analyzed to ensure diagnosis extraction date was reliable. Results:A total of 67,311 suspected MS cases were identified between 2011 and 2021, with 50,320 cases classified as incident MS using the specific definition. The sensitive definition identified 56,918 incident cases. The median age at diagnosis was 40.6 years for the specific definition and 41.5 years for the sensitive definition. The study found stable incidence of MS over the 11-year period (adjusted IRR: 0.998 (95% CI, 0.996-1.001) for the specific cohort). The female-to-male ratio of incident MS cases remained stable, while sex and age-standardized prevalence of MS continued to rise. The median time lag between probable diagnosis and database recording was estimated to less than 18 months, with variations depending on age and method of patient identification. Conclusion:This study provides a comprehensive analysis of MS epidemiology in France, demonstrating RECORD 1.3: If linkage between databases was conducted for the study,</div
Wearing face masks to protect oneself and/or others: Counter-intuitive results from a simple epidemic model accounting for selfish and altruistic human behaviour
No full textWe study a simple SIS epidemic model accounting for human behaviour. Individuals can decide at each instant of time whether or not they wear a face mask. Mask wearing decreases susceptibility to and/or transmission of the disease. We consider a situation in which individuals are unaware of their health status (infected or not), but can perceive disease prevalence at the population level. This assumption fits situations in which asymptomatic people can be numerous and tests are not widely available. Individual decision dynamics depend both on disease prevalence, as a proxy for the risk of being infected or infecting others, and/or the fraction of the population complying to mask-wearing, which people can observe in their everyday life. Specifically, human behaviour is assumed to be driven by imitation dynamics. When the disease does not naturally die out, the model has three types of endemic equilibria: no-compliance, partial-compliance, and full-compliance. Only one of these equilibria can be stable at a time. We assume that the effectiveness of mask-wearing is positively correlated to its cost at the individual level. Increasing mask effectiveness and therefore its individual cost can make the system switch from full-compliance to partial-compliance. This way, increasing mask effectiveness may increase disease prevalence at equilibrium. In other words, disease prevalence is minimized for intermediate mask effectiveness and cost. This is because, when mask-wearing is too effective and therefore costly, part of the population free-rides on the effort of others and drops mask, resulting in increased prevalence. Altogether, our results show that the interplay between epidemiology and human behaviour may lead to counter-intuitive but nevertheless intelligible outcomes, which should be anticipated when designing public health policies.</div