Cord serum cytokines at birth and children's trajectories of mood dysregulation symptoms from 3 to 8 years: The EDEN birth cohort

There is growing evidence that in utero imbalance immune activity plays a role in the development of neurodevelopmental and psychiatric disorders in children. Mood dysregulation (MD) is a debilitating transnosographic syndrome whose underlying pathophysiological mechanisms could be revealed by studying its biomarkers using the Research Domain Criteria (RDoC) model. Our aim was to study the association between the network of cord serum cytokines, and mood dysregulation trajectories in offsprings between 3 and 8 years of age. We used the data of a study nested in the French birth cohort EDEN that took place from 2003 to 2014 and followed mother-child dyads from the second trimester of pregnancy until the children were 8 years of age. The 2002 mother-child dyads were recruited from the general population through their pregnancy follow-up in two French university hospitals. 871 of them were included in the nested cohort and cord serum cytokine levels were measured at birth. Children's mood dysregulation symptoms were assessed with the Strengths and Difficulties Questionnaire Dysregulation Profile at the ages 3, 5 and 8 years in order to model their mood dysregulation trajectories. Out of the 871 participating dyads, 53% of the children were male. 2.1% of the children presented a high mood dysregulation trajectory whereas the others were considered as physiological variations. We found a significant negative association between TNF-α cord serum levels and a high mood dysregulation trajectory when considering confounding factors such as maternal depression during pregnancy (adjusted Odds Ratio (aOR) = 0.35, 95% Confidence Interval (CI) [0.18-0.67]). Immune imbalance at birth could play a role in the onset of mood dysregulation symptoms. Our findings throw new light on putative immune mechanisms implicated in the development of mood dysregulation and should lead to future animal and epidemiological studies.

Associations between symptoms of attention-deficit hyperactivity disorder, socioeconomic status and asthma in children

Socioeconomic status (SES) influences the risk of both physical diseases, such as asthma, and neurodevelopmental conditions, including attention-deficit/hyperactivity disorder (ADHD). Using Causal Mediation Analysis on French birth-cohort data, we found a causal pathway from SES to ADHD symptoms, in part mediated by asthma. An increase in family income at age 3 by one unit resulted in lower ADHD symptoms at age 5, by -0.37 [95% CI: -0.50, -0.24] SDQ-score-points, with additional -0.04 [95% CI: -0.08, -0.01] points reduction indirectly via asthma at age 3, both with statistical significance. Importantly, family income at age 3 exerted both direct and indirect (via asthma) negative effects on later ADHD symptoms with much higher magnitudes for the direct effect. Our findings underscore the importance of apprehending ADHD symptoms in the broader context of socioeconomic disparities, along with their comorbidities with asthma, potentially influencing public health interventions and clinical practice in managing ADHD.

Factors associated with the use of cannabis for self-medication by adults: data from the French TEMPO cohort study

BACKGROUND

Medical cannabis, legalized in many countries, remains illegal in France. Despite an experiment in the medical use of cannabis that began in March 2021 in France, little is known about the factors associated with the use of cannabis for self-medication among adults.

METHODS

Data came from the French TEMPO cohort and were collected between December 2020 and May 2021. Overall, 345 participants aged 27-47 were included. Cannabis for self-medication was defined using the following questions: 'Why do you use cannabis?' and 'In what form do you use cannabis?'. The penalized regression method "Elastic net" was used to determine factors associated with the use of cannabis for self-medication, with the hypothesis that it is mainly used for pain in individuals who have already used cannabis.

RESULTS

More than half of the participants reported having ever used cannabis (58%). Only 10% used it for self-declared medical reasons (n = 36). All self-medication cannabis users, except one, were also using cannabis for recreational purposes. The main factors associated with cannabis use for self-medication vs. other reasons included cannabis use trajectories, the presence of musculoskeletal disorders, tobacco smoking, and parental divorce.

CONCLUSIONS

Engaging in cannabis use during adolescence or early adulthood may increase the likelihood of resorting to self-medication in adulthood. Due to the propensity of individuals with cannabis use during adolescence to resort to uncontrolled products for self-medication, this population should be more systematically targeted and screened for symptoms and comorbidities that may be associated with cannabis use.

Risk factors of suicide in prisons: a comprehensive retrospective cohort study in France, 2017-2020

PURPOSE

Suicide is a leading cause of death in prison and the suicide rates are several times higher in the prison population than in the general population in most countries. Of the studies that have investigated risk factors for suicide in prison, few have controlled for possible confounding factors. The aim of this study is to identify risk factors of suicide among people in French prisons, over a four-year period.

METHODS

All incarcerations that occurred in France during 2017-2020 were eligible. Sociodemographic, criminal and prison characteristics were collected for each incarceration from data of the National Prison Service. Survival univariate and multivariate analyses were performed with a Cox regression model.

RESULTS

358,522 incarcerations were included, of which 449 ended in suicide during the follow-up. The median length of prison stay was 5.1 months. The median age at prison entry was 30 years and 95.8% of incarcerations involved men. The overall suicide rate was 173 [157-189] per 100,000 person-years. Factors associated with suicide in the multivariate model (p < 0.05) were the early stage of incarceration and in particular the first week (HR = 7.6 [5.4-10.8]), violent offences and in particular homicide (HR = 3.0 [2.1-4.2]), French (HR = 1.7 [1.2-2.4]) and other European nationalities (HR = 2.1 [1.4-3.3]), age above 40 (HR = 2.0 [1.5-2.6]), pre-trial incarceration (HR = 1.8 [1.4-2.3]), being separated (HR = 1.6 [1.1-2.3] and having a high school diploma (HR = 1.4 [1.0-1.8]).

CONCLUSIONS

Factors associated with suicide in prison are complex and involve individuals' criminal history as well as conditions of incarceration. These characteristics may be relevant to focus suicide prevention efforts.

Depression and loneliness among Sub-Saharan immigrants living in the greater Paris area: results from the MAKASI empowerment stepped wedge cluster randomised controlled trial

PURPOSE

The MAKASI intervention aimed to empower Sub-Saharan African immigrants living in precarious situations in the Paris metropolitan area. Because there are factors specifically related to immigration that may increase the risk for common mental disorders, the present study aimed to examine participants' levels of depression and loneliness and analyze the effect of the intervention on depression and loneliness.

METHODS

The MAKASI study was designed as a stepped wedge cluster randomized trial. Study participants were recruited through an outreach program led by a nongovernmental organization and randomly assigned to two clusters, with an intervention delay of 3 months between them. Participants were assessed for 6 months after inclusion and the effect of the intervention on depression and loneliness was assessed using generalized linear mixed models. The study was conducted from 2018 to 2021 and took in consideration whether being interviewed during one of the Covid-19 confinement had an effect on the results.

RESULTS

Between 2018 and 2021 a total of 821 subjects participated in the Makasi study. High levels of depression and loneliness were found in the study population. We found no effect of the intervention on depression [95% CI 0.77 to 2.40]. Similarly, no effect of the intervention was found on loneliness [95% CI 0.87 to 2.54].

CONCLUSIONS

The intervention tested did not appear to improve the level of depression and loneliness among participants. However, the high prevalence of mental and emotional problems in the study population suggests a public health crisis among immigrants in the greater Paris area.

CLINICAL TRIAL REGISTRATION NUMBER

 Trial registration Clinicaltrials.gov, NCT04468724 (July 13, 2020).

High screen time and internalizing and externalizing behaviours among children aged 3 to 14 years during the COVID-19 pandemic in France

Children's screen time increased as a result of the COVID-19 pandemic. In the summer of 2021, we explored the association between high screen time over a period of one year since May 2020 and behavioural problems among children and adolescents. The data were derived from the French EpiCov cohort study, collected in spring 2020, autumn 2020, and spring 2021. Participants (N = 1089) responded to online or telephone interviews about one of their children aged 3 to 14 years. Screen time was categorized as high if the daily mean screen time exceeded recommendations at each collection time. The Strengths and Difficulties Questionnaire (SDQ) was completed by parents to identify internalizing (emotional or peer problems) and externalizing (conduct problems or hyperactivity/inattention) behaviours in their children. Among the 1,089 children, 561 (51.5%) were girls, the average age was 8.6 years (SD 3.7). Internalizing behaviours: High screen time was not associated with internalizing behaviours (OR [95% CI] 1.20 [0.90-1.59]) or emotional symptoms (1.00 [0.71-1.41]) while it was associated with peer problems (1.42 [1.04-1.95]). Externalizing behaviours: High screen time was associated with externalizing problems (1.63 [1.01-2.63]) and conduct problems (1.91 [1.15-3.22]) only among older children aged 11 to 14 years. No association with hyperactivity/inattention was found. In a French cohort, exploration of persistent high screen time in the first year of the pandemic and behaviour difficulties in Summer 2021 resulted in mixed findings according to behaviour's type and children's age. These mixed findings warrant further investigation into screen type and leisure/school screen use to enhance future pandemic responses appropriate for children.

Our perception may not be reality: A longitudinal study of the relationship between perceived and actual change in smoking behavior

INTRODUCTION

Results of the impact of lockdowns and stay-at-home orders during the COVID-19 pandemic on changes in cigarette smoking are mixed. Previous studies examining smoking changes during the early stages of the pandemic in 2020 have mainly focused on smoker's perception of changes in cigarette consumption. Such measure has not been widely used in other contexts, and therefore we aim to compare the discrepancy between smokers' perceived changes in cigarette smoking and the actual change in the number of cigarettes smoked, using repeated measurements.

METHODS

We included 134 smokers from the French TEMPO cohort with repeated measurements of their perceived changes in smoking habits during the first phase of the COVID-19 pandemic and the number of cigarettes smoked repeatedly from March to May 2020. We used generalized estimation equations (GEE) to examine the association between changes in the number of cigarettes smoked and the odds of mismatched answers.

RESULTS

The results suggest that at each study wave, 27-45% of participants provided mismatching answers between their perceived change in smoking habits and the actual change in the number of cigarettes smoked daily, measured repeatedly. Results from GEE analysis demonstrated that a mismatching assessment of smoking behavior was elevated among those who had an increase (OR = 2.52 [1.37;4.65]) or a decrease (OR = 5.73 [3.27;10.03]) in number of cigarettes smoked.

DISCUSSION

Our findings highlight the possibility of obtaining different results depending on how changes in tobacco smoking are measured. This highlights the risk of underestimating the actual changes in cigarette smoking during the COVID-19 pandemic, but also more generally when validating public health interventions or smoking cessation programs. Therefore, objective measures such as the actual consumption of psychoactive substances should be utilized, preferably on a longitudinal basis, to mitigate recall bias.

A qualitative evaluation of the use of Problem Management Plus (PM+) among Arabic-speaking migrants with psychological distress in France - The APEX study

ABSTRACTBackground: Feasibility studies with non-French speaking migrants in France are needed to inform appropriate adaptation of psychosocial intervention procedures.Objective: To test the WHO Problem Management Plus (PM+) intervention protocol for Arabic-speaking migrants in the Paris metropolitan region.Methods: Between 2019 and 2021 we recruited participants from three accommodation centres receiving asylum seekers or migrants experiencing social and economic difficulties. Participants experiencing psychological distress underwent five PM + sessions with trained helpers. Feasibility was evaluated through 15 interviews with 8 participants, 4 helpers, and 3 study supervisors. Interview topics covered PM + implementation in general and for each component. We also sought to understand problems with delivery and gathered suggestions for improvement. Data were analysed thematically using a deductive approach.Results: We found implementation of PM + to be feasible, with predominantly positive reactions from participants, helpers and study staff. All intervention components were considered beneficial, with breathing exercises considered easy to implement and often sustained. Selection of problems and strategies to address them were described as challenging to execute. Psychosocial support from and rapport with helpers and the use of the native language were considered key strengths of the programme. However, we observed the need for complementary or higher intensity psychological support in some cases. Findings also highlighted the importance of addressing distress among non-specialist helpers delivering PM + . Finally, local guidance to social resources were suggested to be added in the protocol.Conclusion: PM + was well-liked and feasible, with cultural adjustments and increased access to community resources for migrants needed.

High proportion of post-migration HIV acquisition in migrant men who have sex with men receiving HIV care in the Paris region, and associations with social disadvantage and sexual behaviours: results of the ANRS-MIE GANYMEDE study, France, 2021 to 2022

BackgroundSome migrant men who have sex with men (MSM) acquire HIV in France.AimsWe investigated, in migrant MSM receiving HIV care in France, the (i) rate of post-migration-HIV acquisition in France, (ii) delay between arrival and HIV acquisition and (iii) factors affecting HIV acquisition within 1 year after migration.MethodsThis cross-sectional study focused on ≥ 18-year-old MSM born outside France, receiving HIV care in the Paris region. Information on migration history, socioeconomic condition, sexual activity, and health was collected in May 2021-June 2022 through self-administered questionnaires and medical records. Post-migration-HIV-acquisition rate and delay between arrival in France and HIV acquisition were estimated from biographical data and CD4+ T-cell counts. Predictors of HIV acquisition within 1 year after migration were determined using logistic regression.ResultsOverall post-migration HIV-acquisition rate was 61.7% (715/1,159; 95%CI: 61.2-62.2), ranging from 40.5% (95%CI: 39.6-41.6) to 85.4% (95%CI: 83.9-86.0) in participants from Latin America and North Africa. Among post-migration-HIV acquisitions, those within 1 year after migration represented 13.1% overall (95%CI: 11.6-14.6), being highest in participants from sub-Saharan Africa (25%; 95%CI: 21.5-28.3). Participants ≥ 15-years old at migration, with post-migration-acquired HIV, had a 7.5-year median interval from arrival in France to HIV acquisition (interquartile range (IQR): 3.50-14.75). Older age at arrival, region of origin (sub-Saharan Africa and Asia), degree of social disadvantage and numbers of sexual partners were independently associated with acquiring HIV within 1 year in France.ConclusionOur findings may guide HIV prevention policies for most vulnerable migrants to Europe.

Proportion of At-Risk Alcohol Consumers According to the New French Guidelines: Cross-Sectional Weighted Analyses From the CONSTANCES Cohort

Objective: To estimate the proportion of the participants of the French national population-based CONSTANCES cohort exceeding the new low-risk drinking guidelines according to sociodemographic and clinical factors. Methods: From 34,470 participants with follow-up data in 2019, among volunteers aged 18-69 years and invited to enroll in the CONSTANCES cohort in 2016 and 2017, weighted prevalence and odds ratios with 95% confidence intervals (CI) exceeding the guidelines using logistic regressions were presented stratified for age, gender, education, occupational grade, employment, income, marital status, pregnancy, work stress, depression, alcohol dependence, binge drinking, cannabis use, smoking status, e-cigarette use, cardiovascular diseases, and cancer. Results: The guidelines were exceeded more by men at 60.2% (95%CI: 59.3%-61.0%) than by women at 36.6% (95%CI: 35.9%-37.4%). Exceeding the guidelines increased with age, socioeconomic status, smoking, vaping, using cannabis, binge drinking, and alcohol dependence. Being depressed was associated with exceeding the guidelines in women. Even though pregnant women were less likely to exceed the guidelines, 7.6% (95%CI: 5.4%-10.6%) were at-risk drinkers. Conclusion: These findings highlight the need to implement effective prevention measures for at-risk alcohol use among the French population.

Suicide following a conviction, solitary confinement, or transfer in people incarcerated: A comprehensive retrospective cohort study in France, 2017-2020

INTRODUCTION

Suicide rates are higher in prison than in the general population in most countries. The proximity of some suicides to prison events has only received little attention in comparative studies. The aim of this study was to assess the relationship between suicide and four prison events: conviction, disciplinary solitary confinement, nondisciplinary solitary confinement and inter-prison transfer, in a national retrospective cohort study of people in prison.

METHODS

All incarcerations in France that occurred during 2017-2020 were eligible. Data were collected from an administrative database of the National Prison Service. Survival bivariate and multivariate analyses were performed with a Cox regression model.

RESULTS

Of 358,522 incarcerations were included, among which 469,348 events and 449 suicides occurred. In multivariate analysis, suicide risk was higher the first day of disciplinary solitary confinement (HR = 42.1 [21.5-82.7] and HR = 119.0 [71.5-197.9], before and after a government decree on the disciplinary system, respectively. It was higher within 2 weeks after a transfer (HR = 3.5 [2.3-5.2])) or entry in nondisciplinary solitary confinement (HR = 6.7 [3.4-13.3]) and lower within 2 weeks after a conviction (HR = 0.6 [0.4-1.0]).

CONCLUSION

Solitary confinement and transfer were found to be precipitating factors of suicide in people who are incarcerated. These results offer interesting perspectives on prevention.

Intergenerational transmission of tobacco smoking: The role of the child's behavioral difficulties. Data from the Danish National Birth cohort (DNBC)

AIMS

This study explores the role of offspring behavioral difficulties in the intergeneration transmission of tobacco smoking.

METHODS

This longitudinal cohort study is based on children born in Denmark in 1996-2003 participating in the Danish National Birth Cohort (DNBC), followed-up until 18years of age. We included mother-child pairs with complete data regarding the exposure (4 trajectories of maternal daily smoking quantity during pregnancy: low, intermediate/stable, intermediate/decreasing and high), outcome (offspring daily smoking status at 18 years) and mediator (offspring symptoms of hyperactivity-inattention at 11 years), that is 24,588 mother-child pairs.

RESULTS

In our study population, during pregnancy respectively 86.2%, 6.80%, 4.08% and 2.97% mothers belonged to the low, intermediate/stable, intermediate/decreasing and high smoking trajectory groups. After controlling for covariates using propensity scores, the direct effect of maternal smoking in pregnancy on offspring smoking in adolescence was statistically significant, especially when the mother belonged to the intermediate/stable smoking trajectory group (ORIPW = 2.09, 95% CI: 1.70 - 2.61) or to the high smoking trajectory group (ORIPW = 2.08, 95% CI: 1.52 - 3.11) compared to the low smoking trajectory group. None of the indirect effects of maternal smoking in pregnancy were statistically significant, and neither were the proportions mediated.

CONCLUSION

Maternal pregnancy smoking seems to have an influence on offspring smoking in early adulthood, which does not appear to be mediated by offspring behavioral difficulties. Women should be strongly encouraged to quit smoking in pregnancy to reduce both short and long-term health risks among their offspring.

The association between the use of video games, social media and online dating sites, and the symptoms of anxiety and/or depression in adults aged 25 and over

People tend to spend more time in front of their screens, which can have repercussions on their social life, physical and mental health. This topic has mainly been studied in adolescents. Therefore, our study tested associations between the use of video games, social media and online dating leading to sexual relations (ODLSR), and symptoms of anxiety and/or depression among adults aged 25 and over. Data from the 2018 TEMPO cohort study were analyzed (n = 853, 65.0% women, aged 25-44, with an average of 37.4 ± 3.7 years). The exposure variables were as follows: (a) the frequency of video game use, (b) time spent on social media and (c) ODLSR. Data were analyzed using multivariate logistic regression models, adjusted for participants' sociodemographic characteristics as well as history of mental health problems. Among the participants, 8.6% presented symptoms of anxiety and/or depression. An association between ODLSR and symptoms of anxiety and/or depression was found, especially among women. The results of this study will facilitate the improvement of support and care for adults, especially those with symptoms of anxiety and/or depression using dating applications. Future studies should investigate the determinants of using online meeting websites and their relationship with the occurrence of psychological difficulties in longitudinal studies to establish causality.

Do Determinants of Smoking Cessation and Relapse Differ between Men and Women? Data from a French National Study

Introduction: There is limited understanding of different predictors of smoking cessation success (SCS) among women and men, despite well-documented differences in smoking behavior.Methods: Using data from DePICT (Description des Perceptions, Images, et Comportements liés au Tabagisme), a national survey of French adults which recruited 2377 regular and former smokers we investigated whether major determinants of SCS differed by sex. Factors associated with unsuccessful vs. No successful quit attempt; vs. SCS were studied using multivariate multinomial logistic regression analyses stratified by sex.Results: Women and men share some determinants of SCS including no cannabis use, living in a nonsmoker household and importance giving to being a nonsmoker. However, no e-cigarette use, low-to-moderate alcohol consumption, early smoking initiation, and higher education were associated with SCS only among women. No use of nicotine replacement, having family members who smoke, family opinion on smoking and current employment, were associated with SCS only among men. Neutral or negative friends' opinion on smoking or living with a smoker were associated with unsuccessful smoking attempts among men.Conclusions: Our results show differences between determinants of SCS according to sex, which highlights the importance of developing tailored interventions that account for sex/gender differences in smoking cessation.

Social determinants in prenatal antidepressant use and continuation: Systematic review and meta-analysis

INTRODUCTION

Depression is one of the most common co-morbidities during pregnancy; with severe symptoms, antidepressants are sometimes recommended. Social determinants are often linked with antidepressant use in the general population, and it is not known if this is the case for pregnant populations. Our objective was to determine if social determinants are associated with prenatal antidepressant intake via a systematic review and meta-analysis.

METHODS

A systematic search of five databases was conducted to identify publications from inception to October 2022 that reported associations with prenatal antidepressant intake (use/continuation) and one or more social determinants: education, race, immigration status, relationship, income, or employment. Eligible studies were included in random effects meta-analyses.

RESULTS

A total of 23 articles describing 22 studies were included. Education was significantly and positively associated with prenatal antidepressant continuation and heterogeneity was moderate. (Odds ratio = 0.83; 95% CI, 0.78 to 0.89; p < 0.00001; I2  = 53%). Meta-analyses of antidepressant use and education, race, and relationship status, and antidepressant continuation and income were not significant with high levels of heterogeneity.

DISCUSSION

While most social determinants in this review were not linked with prenatal antidepressant intake, lower maternal education level does seem to be associated with lower rates of prenatal antidepressant continuation.

CONCLUSIONS

Education appears to be linked with prenatal antidepressant intake. The low number of included studies precludes conclusive evidence for other social determinants.

Social patterning of childhood overweight in the French national ELFE cohort

An inverse social gradient in early childhood overweight has been consistently described in high-income countries; however, less is known about the role of migration status. We studied the social patterning of overweight in preschool children according to the mother's socio-economic and migration background. For 9250 children of the French ELFE birth cohort with body mass index collected at age 3.5 years, we used nested logistic regression to investigate the association of overweight status in children with maternal educational level, occupation, household income and migration status. Overall, 8.3% (95%CI [7.7-9.0]) of children were classified as overweight. The odds of overweight was increased for children from immigrant mothers (OR 2.22 [95% CI 1.75-2.78]) and descendants of immigrant mothers (OR 1.35 [1.04-2.78]) versus non-immigrant mothers. The highest odds of overweight was also observed in children whose mothers had low education, were unemployed or students, or were from households in the lowest income quintile. Our findings confirm that socio-economic disadvantage and migration status are risk factors for childhood overweight. However, the social patterning of overweight did not apply uniformly to all variables. These new and comprehensive insights should inform future public health interventions aimed at tackling social inequalities in childhood overweight.

Association between relative age at school and persistence of ADHD in prospective studies: an individual participant data meta-analysis

BACKGROUND

The youngest children in a school class are more likely than the oldest to be diagnosed with ADHD, but this relative age effect is less frequent in older than in younger school-grade children. However, no study has explored the association between relative age and the persistence of ADHD diagnosis at older ages. We aimed to quantify the association between relative age and persistence of ADHD at older ages.

METHODS

For this meta-analysis, we searched MEDLINE, Embase, CINAHL, PsycINFO, and PubPsych up to April 1, 2022, with terms related to "cohort" and "ADHD" with no date, publication type, or language restrictions. We gathered individual participant data from prospective cohorts that included at least ten children identified with ADHD before age 10 years. ADHD was defined by either a clinical diagnosis or symptoms exceeding clinical cutoffs. Relative age was recorded as the month of birth in relation to the school-entry cutoff date. Study authors were invited to share raw data or to apply a script to analyse data locally and generate anonymised results. Our outcome was ADHD status at a diagnostic reassessment, conducted at least 4 years after the initial assessment and after age 10 years. No information on sex, gender, or ethnicity was collected. We did a two-stage random-effects individual participant data meta-analysis to assess the association of relative age with persistence of ADHD at follow-up. This study was registered with PROSPERO, CRD42020212650.

FINDINGS

Of 33 119 studies generated by our search, we identified 130 eligible unique studies and were able to gather individual participant data from 57 prospective studies following up 6504 children with ADHD. After exclusion of 16 studies in regions with a flexible school entry system that did not allow confident linkage of birthdate to relative age, the primary analysis included 41 studies in 15 countries following up 4708 children for a period of 4 to 33 years. We found that younger relative age was not statistically significantly associated with ADHD persistence at follow-up (odds ratio 1·02, 95% CI 0·99-1·06; p=0·19). We observed statistically significant heterogeneity in our model (Q=75·82, p=0·0011, I2=45%). Participant-level sensitivity analyses showed similar results in cohorts with a robust relative age effect at baseline and when restricting to cohorts involving children with a clinical diagnosis of ADHD or with a follow-up duration of more than 10 years.

INTERPRETATION

The diagnosis of ADHD in younger children in a class is no more likely to be disconfirmed over time than that of older children in the class. One interpretation is that the relative age effect decreases the likelihood of children of older relative age receiving a diagnosis of ADHD, and another is that assigning a diagnostic label of ADHD leads to unexplored carryover effects of the initial diagnosis that persist over time. Future studies should be conducted to explore these interpretations further.

FUNDING

None.

Urbanicity and psychotic disorders: Facts and hypotheses

In the present qualitative literature review, we summarise data on psychotic disorders and urbanicity, focusing particularly on recent findings. Longitudinal studies of the impact of urbanicity on the risk for psychotic disorders have consistently shown a significant association, with a relative risk between 2 and 2.5. However, most of the original studies were conducted in Western Europe, and no incidence studies were conducted in low- and middle-income countries. European studies suggest that neighbourhood-level social fragmentation and social capital may partly explain this association. Exposure to air pollution (positive association) and green space (negative association) may also be part of the explanation, but to date, available data do not make it possible to conclude if they act independently from urbanicity, or as part of the effect of urbanicity on psychotic disorders. Finally, several studies have consistently shown significant associations between the polygenic risk score for schizophrenia and urbanicity, with several possible explanations (pleiotropic effects, results of prodromic symptoms, or selection/intergenerational hypothesis). Thus, more studies are needed to understand the factors that explain the association between urbanicity and the risk of psychotic disorders. Further studies should account for the interdependence and/or interactions of different psychosocial and physical exposures (as well as gene-environment interactions), and explore this association in low- and middle-income countries.

Uncertainty in the association between socio-demographic characteristics and mental health

Questionnaires are among the most basic and widespread tools to assess the mental health of a population in epidemiological and public health studies. Their most obvious advantage (firsthand self-report) is also the source of their main problems: the raw data requires interpretation, and are a snapshot of the specific sample's status at a given time. Efforts to deal with both issues created a bi-dimensional space defined by two orthogonal axes, in which most of the quantitative mental health research can be located. Methods aimed to assure that mental health diagnoses are solidly grounded on existing raw data are part of the individual validity axis. Tools allowing the generalization of the results across the entire population compose the collective validity axis. This paper raises a different question. Since one goal of mental health assessments is to obtain results that can be generalized to some extent, an important question is how robust is a questionnaire result when applied to a different population or to the same population at a different time. In this case, there is deep uncertainty, without any a priori probabilistic information. The main claim of this paper is that this task requires the development of a new robustness to deep uncertainty axis, defining a three-dimensional research space. We demonstrate the analysis of deep uncertainty using the concept of robustness in info-gap decision theory. Based on data from questionnaires collected before and during the Covid-19 pandemic, we first locate a mental health assessment in the space defined by the individual validity axis and the collective validity axis. Then we develop a model of info-gap robustness to uncertainty in mental health assessment, showing how the robustness to deep uncertainty axis interacts with the other two axes, highlighting the contributions and the limitations of this approach. The ability to measure robustness to deep uncertainty in the mental health realm is important particularly in troubled and changing times. In this paper, we provide the basic methodological building blocks of the suggested approach using the outbreak of Covid-19 as a recent example.

Changes in alcohol consumption according to the duration of unemployment: prospective findings from the French CONSTANCES cohort

OBJECTIVES

To prospectively examine the association between the duration of unemployment among job seekers and changes in alcohol use in a year.

DESIGN

A prospective study.

SETTING

French population-based CONSTANCES cohort.

PARTICIPANTS

We selected 84 943 participants from the CONSTANCES cohort included between 2012 and 2019 who, at baseline and 1-year follow-up, were either employed or job-seeking.

OUTCOME MEASURES

Multinomial logistic regression models computed the odds of reporting continuous no alcohol use, at-risk alcohol use, increased or decreased alcohol use compared with being continuously at low risk and according to employment status. The duration of unemployment was self-reported at baseline; thus, the employment status at 1-year follow-up was categorised as follows: (1) employed, (2) return to employment since less than a year, (3) unemployed for less than 1 year, (4) unemployed for 1 to 3 years and (5) unemployed for 3 years or more. Analyses were adjusted for age, gender, education, household monthly income, marital status, self-rated health, smoking status and depressive state.

RESULTS

Compared with being continuously at low risk (ie, ≤10 drinks per week), the unemployment categories were associated in a dose-dependent manner with an increased likelihood of reporting continuous no alcohol use (OR: 1.74-2.50), being continuously at-risk (OR: 1.21-1.83), experiencing an increase in alcohol use (OR: 1.21-1.51) and a decrease in alcohol use (OR: 1.17-1.84).

CONCLUSION

Although our results suggested an association between the duration of unemployment and a decrease in alcohol use, they also revealed associations between at-risk and increased alcohol use. Thus, screening for alcohol use among unemployed job seekers must be reinforced, especially among those with long-term unemployment.

Addressing mental health problems among persons without stable housing in the context of the COVID-19 pandemic: study protocol for a randomised trial. RESPOND - France

BACKGROUND

The COVID-19 pandemic has had an impact on population-wide mental health and well-being. Although people experiencing socioeconomic disadvantage may be especially vulnerable, they experience barriers in accessing mental health care. To overcome these barriers, the World Health Organization (WHO) designed two scalable psychosocial interventions, namely the web-based Doing What Matters in Times of Stress (DWM) and the face-to-face Problem Management Plus (PM+), to help people manage stressful situations. Our study aims to test the effectiveness of a stepped-care program using DWM and PM + among individuals experiencing unstable housing in France - a majority of whom are migrant or have sought asylum.

METHODS

This is a randomised controlled trial to evaluate the effectiveness and cost effectiveness of a stepped-care program using DWM and PM + among persons with psychological distress and experiencing unstable housing, in comparison to enhanced care as usual (eCAU). Participants (N = 210) will be randomised to two parallel groups: eCAU or eCAU plus the stepped-care program. The main study outcomes are symptoms of depression and anxiety measured using the Patient Health Questionnaire Anxiety and Depression Scale (PHQ-ADS).

DISCUSSION

This randomised controlled trial will contribute to a better understanding of effective community-based scalable strategies that can help address the mental health needs of persons experiencing socioeconomic disadvantage, whose needs are high yet who frequently have limited access to mental health care services.

TRIAL REGISTRATION

this randomised trial has been registered at ClinicalTrials.gov under the number NCT05033210.

Effectiveness of a scalable, remotely delivered stepped-care intervention to reduce symptoms of psychological distress among Polish migrant workers in the Netherlands: study protocol for the RESPOND randomised controlled trial

BACKGROUND

The COVID-19 pandemic has negatively affected the mental health of international migrant workers (IMWs). IMWs experience multiple barriers to accessing mental health care. Two scalable interventions developed by the World Health Organization (WHO) were adapted to address some of these barriers: Doing What Matters in times of stress (DWM), a guided self-help web application, and Problem Management Plus (PM +), a brief facilitator-led program to enhance coping skills. This study examines whether DWM and PM + remotely delivered as a stepped-care programme (DWM/PM +) is effective and cost-effective in reducing psychological distress, among Polish migrant workers with psychological distress living in the Netherlands.

METHODS

The stepped-care DWM/PM + intervention will be tested in a two-arm, parallel-group, randomized controlled trial (RCT) among adult Polish migrant workers with self-reported psychological distress (Kessler Psychological Distress Scale; K10 > 15.9). Participants (n = 212) will be randomized into either the intervention group that receives DWM/PM + with psychological first aid (PFA) and care-as-usual (enhanced care-as-usual or eCAU), or into the control group that receives PFA and eCAU-only (1:1 allocation ratio). Baseline, 1-week post-DWM (week 7), 1-week post-PM + (week 13), and follow-up (week 21) self-reported assessments will be conducted. The primary outcome is psychological distress, assessed with the Patient Health Questionnaire Anxiety and Depression Scale (PHQ-ADS). Secondary outcomes are self-reported symptoms of depression, anxiety, posttraumatic stress disorder (PTSD), resilience, quality of life, and cost-effectiveness. In a process evaluation, stakeholders' views on barriers and facilitators to the implementation of DWM/PM + will be evaluated.

DISCUSSION

To our knowledge, this is one of the first RCTs that combines two scalable, psychosocial WHO interventions into a stepped-care programme for migrant populations. If proven to be effective, this may bridge the mental health treatment gap IMWs experience.

TRIAL REGISTRATION

Dutch trial register NL9630, 20/07/2021, https://www.onderzoekmetmensen.nl/en/trial/27052.

Health professional's perception of a smoking cessation intervention among disadvantaged patients participating in a pragmatic randomized trial

INTRODUCTION

Individuals who have a low socio-economic position (SEP) are more likely to smoke and face greater barriers to quitting tobacco. However, the effectiveness of tailored interventions has been limited probably due to specific challenges relative to this population. We conducted a mixed-method study to better understand health professionals' perceptions and barriers when implementing a preference-based smoking cessation (SC) intervention among disadvantaged smokers.

METHODS

A self-administered online questionnaire was sent to health professionals (doctors' and other health professionals specialized in SC) participating in "STOP" a pragmatic multicentre randomized controlled trial. Perceptions regarding patient eligibility, the doctor-patient relationship, general study organization, and satisfaction were measured.

RESULTS

Twenty-eight STOP study investigators responded. Health professionals prioritize smoking cessation for disadvantaged patients, but face challenges in approaching and following them. A research intervention providing cessation tools based on preference was deemed useful but generally undermined by time constraints. Health professionals' preconceptions regarding patients in low SEP having other "pressing problems" which might be exacerbated by quitting smoking were also identified. Further, participation in a research intervention was perceived as not satisfactory due to workload and lack of time.

CONCLUSION

Our results highlight general barriers inherent to implementing pragmatic trials. They also present specific challenges in smoking cessation trials among disadvantaged population, essential to advance equity in tobacco control.

Children with a history of both maternal immune activation and prematurity are not at increased risk of ADHD symptoms

Maternal autoimmune diseases (AID) are risk factors for Attention Deficit Hyperactivity Disorder (ADHD). Animal studies suggest that maternal immune activation (MIA) is a disease primer for ADHD, with second environmental factor precipitating the onset of the disease. Prematurity is also a major risk factor for ADHD. In this study, we sought to explore the interaction between parental AID and prematurity on ADHD risk in a community sample. Children of AID parents born prematurely appeared at increased odds of ADHD but these two risk factors do not appear to be additive (OR 1.39 [95 CI 0.75; 2.46]). Longitudinal studies with larger numbers of participants are needed.

The effect on women's health of extending parental leave: a quasi-experimental registry-based cohort study

BACKGROUND

Parental leave policies have been hypothesized to benefit mothers' mental health. We assessed the impact of a 6-week extension of parental leave in Denmark on maternal mental health.

METHODS

We linked individual-level data from Danish national registries on maternal sociodemographic characteristics and psychiatric diagnoses. A regression discontinuity design was applied to study the increase in parental leave duration after 26 March 1984. We included women who had given birth between 1 January 1981 and 31 December 1987. Our outcome was a first psychiatric diagnosis following the child's birth, ascertained as the first day of inpatient hospital admission for any psychiatric disorder. We presented cumulative incidences for the 30-year follow-up period and reported absolute risk differences between women eligible for the reform vs not, in 5-year intervals.

RESULTS

In all, 291 152 women were followed up until 2017, death, emigration or date of first psychiatric diagnosis. The median follow-up time was 29.99 years, corresponding to 10 277 547 person-years at risk. The cumulative incidence of psychiatric diagnoses at 30 years of follow-up was 59.5 (95% CI: 57.4 to 61.6) per 1000 women in the ineligible group and 57.5 (95% CI: 55.6 to 59.4) in the eligible group. Eligible women took on average 32.85 additional days of parental leave (95% CI: 29.20 to 36.49) and had a lower probability of having a psychiatric diagnosis within 5 years [risk difference (RD): 2.4 fewer diagnoses per 1000 women, 95% CI: 1.5 to 3.2] and up to 20 years after the birth (RD: 2.3, 95% CI: 0.4 to 4.2). In subgroup analyses, the risk reduction was concentrated among low-educated, low-income and single women.

CONCLUSIONS

Longer parental leave may confer mental health benefits to women, in particular to those from disadvantaged backgrounds.

Prevalence of smoking during pregnancy and associated social inequalities in developed countries over the 1995-2020 period: A systematic review

BACKGROUND

Smoking during pregnancy (SDP) is an important source of preventable morbidity and mortality for both mother and child.

OBJECTIVES

The aim of this study was to describe changes in the prevalence of SDP over the last 25 years in developed countries (Human Development Index >0.8 in 2020) and associated social inequalities.

DATA SOURCES

A systematic review was conducted based on a search in PubMed, Embase and PsycInfo databases and government sources.

STUDY SELECTION AND DATA EXTRACTION

Published studies between January 1995 and March 2020, for which the primary outcome was to assess the national prevalence of SDP and the secondary outcome was to describe related socio-economic data were included in the analysis. The selected articles had to be written in English, Spanish, French or Italian.

SYNTHESIS

The articles were selected after successive reading of the titles, abstracts and full-length text. An independent double reading with intervention of a third reader in case of disagreement allowed including 35 articles from 14 countries in the analysis.

RESULTS

The prevalence of SDP differed across the countries studied despite comparable levels of development. After 2015, the prevalence of SDP ranged between 4.2% in Sweden and 16.6% in France. It was associated with socio-economic factors. The prevalence of SDP slowly decreased over time, but this overall trend masked inequalities within populations. In Canada, France and the United States, the prevalence decreased more rapidly in women of higher socio-economic status, and inequalities in maternal smoking were more marked in these countries. In the other countries, inequalities tended to decrease but remained significant.

CONCLUSIONS

During pregnancy, that is a period described as a window of opportunity, smoking and social vulnerability factors need to be detected to implement targeted prevention strategies aiming at reducing related social inequalities.

Epigenome-Wide Associations of Placental DNA Methylation and Behavioral and Emotional Difficulties in Children at 3 Years of Age

The placenta is a key organ for fetal and brain development. Its epigenome can be regarded as a biochemical record of the prenatal environment and a potential mechanism of its association with the future health of the fetus. We investigated associations between placental DNA methylation levels and child behavioral and emotional difficulties, assessed at 3 years of age using the Strengths and Difficulties Questionnaire (SDQ) in 441 mother-child dyads from the EDEN cohort. Hypothesis-driven and exploratory analyses (on differentially methylated probes (EWAS) and regions (DMR)) were adjusted for confounders, technical factors, and cell composition estimates, corrected for multiple comparisons, and stratified by child sex. Hypothesis-driven analyses showed an association of cg26703534 (AHRR) with emotional symptoms, and exploratory analyses identified two probes, cg09126090 (intergenic region) and cg10305789 (PPP1R16B), as negatively associated with peer relationship problems, as well as 33 DMRs, mostly positively associated with at least one of the SDQ subscales. Among girls, most associations were seen with emotional difficulties, whereas in boys, DMRs were as much associated with emotional than behavioral difficulties. This study provides the first evidence of associations between placental DNA methylation and child behavioral and emotional difficulties. Our results suggest sex-specific associations and might provide new insights into the mechanisms of neurodevelopment.

Coping with COVID: risk and resilience factors for mental health in a German representative panel study

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic might affect mental health. Data from population-representative panel surveys with multiple waves including pre-COVID data investigating risk and protective factors are still rare.

METHODS

In a stratified random sample of the German household population (n = 6684), we conducted survey-weighted multiple linear regressions to determine the association of various psychological risk and protective factors assessed between 2015 and 2020 with changes in psychological distress [(PD; measured via Patient Health Questionnaire for Depression and Anxiety (PHQ-4)] from pre-pandemic (average of 2016 and 2019) to peri-pandemic (both 2020 and 2021) time points. Control analyses on PD change between two pre-pandemic time points (2016 and 2019) were conducted. Regularized regressions were computed to inform on which factors were statistically most influential in the multicollinear setting.

RESULTS

PHQ-4 scores in 2020 (M = 2.45) and 2021 (M = 2.21) were elevated compared to 2019 (M = 1.79). Several risk factors (catastrophizing, neuroticism, and asking for instrumental support) and protective factors (perceived stress recovery, positive reappraisal, and optimism) were identified for the peri-pandemic outcomes. Control analyses revealed that in pre-pandemic times, neuroticism and optimism were predominantly related to PD changes. Regularized regression mostly confirmed the results and highlighted perceived stress recovery as most consistent influential protective factor across peri-pandemic outcomes.

CONCLUSIONS

We identified several psychological risk and protective factors related to PD outcomes during the COVID-19 pandemic. A comparison of pre-pandemic data stresses the relevance of longitudinal assessments to potentially reconcile contradictory findings. Implications and suggestions for targeted prevention and intervention programs during highly stressful times such as pandemics are discussed.

Effectiveness of a mental health stepped-care programme for healthcare workers with psychological distress in crisis settings: a multicentre randomised controlled trial

BACKGROUND

Evidence-based mental health interventions to support healthcare workers (HCWs) in crisis settings are scarce.

OBJECTIVE

To evaluate the capacity of a mental health intervention in reducing anxiety and depression symptoms in HCWs, relative to enhanced care as usual (eCAU), amidst the COVID-19 pandemic.

METHODS

We conducted an analyst-blind, parallel, multicentre, randomised controlled trial. We recruited HCWs with psychological distress from Madrid and Catalonia (Spain). The intervention arm received a stepped-care programme consisting of two WHO-developed interventions adapted for HCWs: Doing What Matters in Times of Stress (DWM) and Problem Management Plus (PM+). Each intervention lasted 5 weeks and was delivered remotely by non-specialist mental health providers. HCWs reporting psychological distress after DWM completion were invited to continue to PM+. The primary endpoint was self-reported anxiety/depression symptoms (Patient Health Questionnaire-Anxiety and Depression Scale) at week 21.

FINDINGS

Between 3 November 2021 and 31 March 2022, 115 participants were randomised to stepped care and 117 to eCAU (86% women, mean age 37.5). The intervention showed a greater decrease in anxiety/depression symptoms compared with eCAU at the primary endpoint (baseline-adjusted difference 4.4, 95% CI 2.1 to 6.7; standardised effect size 0.8, 95% CI 0.4 to 1.2). No serious adverse events occurred.

CONCLUSIONS

Brief stepped-care psychological interventions reduce anxiety and depression during a period of stress among HCWs.

CLINICAL IMPLICATIONS

Our results can inform policies and actions to protect the mental health of HCWs during major health crises and are potentially rapidly replicable in other settings where workers are affected by global emergencies.

TRIAL REGISTRATION NUMBER

NCT04980326.

Are we equally at risk of changing smoking behavior during a public health crisis? Impact of educational level on smoking from the TEMPO cohort

BACKGROUND

The COVID-19 pandemic as a public health crisis has led to a significant increase in mental health difficulties. Smoking is strongly associated with mental health conditions, which is why the pandemic might have influenced the otherwise decline in smoking rates. Persons belonging to socioeconomically disadvantaged groups may be particularly affected, both because the pandemic has exacerbated existing social inequalities and because this group was more likely to smoke before the pandemic. We examined smoking prevalence in a French cohort study, focusing on differences between educational attainment. In addition, we examined the association between interpersonal changes in tobacco consumption and educational level from 2018 to 2021.

METHODS

Using four assessments of smoking status available from 2009 to 2021, we estimated smoking prevalence over time, stratified by highest educational level in the TEMPO cohort and the difference was tested using chi² test. We studied the association between interpersonal change in smoking status between 2018 and 2021 and educational attainment among 148 smokers, using multinomial logistic regression.

RESULTS

Smoking prevalence was higher among those with low education. The difference between the two groups increased from 2020 to 2021 (4.8-9.4%, p < 0.001). Smokers with high educational level were more likely to decrease their tobacco consumption from 2018 to 2021 compared to low educated smokers (aOR = 2.72 [1.26;5.89]).

CONCLUSION

Current findings showed a widening of the social inequality gap in relation to smoking rates, underscoring the increased vulnerability of persons with low educational level to smoking and the likely inadequate focus on social inequalities in relation to tobacco control policies during the pandemic.

Views and experiences of migrants and stakeholders involved in social and health care for migrants in Italy during the COVID-19 pandemic: a qualitative study

BACKGROUND

The COVID-19 pandemic has had major and potentially long-lasting effects on mental health and wellbeing across populations worldwide. However, these impacts were not felt equally, leading to an exacerbation of health inequalities, especially affecting vulnerable populations such as migrants, refugees and asylum seekers. Aiming to inform the adaptation and implementation of psychological intervention programmes, the present study investigated priority mental health needs in this population group.

METHODS

Participants were adult asylum seekers, refugees and migrants (ARMs) and stakeholders with experience in the field of migration living in Verona, Italy, and fluent in Italian and English. A two-stage process was carried out to examine their needs using qualitative methods including free listing interviews and focus group discussions, according to Module One of the DIME (Design, Implementation, Monitoring, and Evaluation) manual. Data were analyzed using an inductive thematic analyses approach.

RESULTS

A total of 19 participants (12 stakeholders, 7 ARMs) completed the free listing interviews and 20 participants (12 stakeholders and 8 ARMs) attended focus group discussions. Salient problems and functions that emerged during free listing interviews were discussed during the focus group discussions. During the COVID-19 pandemic, ARMs struggled with many everyday living difficulties in their resettlement country due to social and economic issues, revealing a strong influence of contextual factors in determining mental health. Both ARMs and stakeholders highlighted a mismatch between needs, expectations and interventions as factors that may hamper proper implementation of health and social programmes.

CONCLUSIONS

The present findings could help in the adaptation and implementation of psychological interventions targeting the needs of asylum seekers, refugees and migrants aiming to find a match between needs, expectations, and the corresponding interventions.

TRIAL REGISTRATION

Registration number 2021-UNVRCLE-0106707, February 11 2021.

Housing conditions and changes in professional activity during lockdown and the risk of prevalent and incident depression: Findings from the CONSTANCES cohort

BACKGROUND

Material conditions of lockdown and changes in regular functioning may have played a role on depressive manifestations. We aimed to examine the association between housing conditions and changes in professional activity and depression during the first COVID-19 outbreak in France.

METHOD

Participants of the CONSTANCES cohort were followed online. A first questionnaire covered the lockdown period (assessing housing conditions and changes in professional activity), and a second the post-lockdown period (assessing depression using the Center of Epidemiologic Studies Depression-Scale (CES-D)). Incident depression was also estimated (with a previous CES-D measure). Logistic regression models were applied.

RESULTS

22,042 participants (median age 46 years, 53.2 % women) were included and 20,534 had a previous CES-D measure. Depression was associated with female gender, lower household income and past history of depression. A negative gradient between the number of rooms and the likelihood of depression was consistently observed (OR = 1.55 95 % [1.19-2.00] for one room, OR = 0.76 [0.65-0.88] for seven rooms), while a U-shape relationship was observed with the number of people living together (OR = 1.62 [1.42-1.84] for living alone, OR = 1.44 [1.07-1.92] for six persons). These associations were also observed with incident depression. Changes in professional activity were associated with depression (Started distance working (OR = 1.33 [1.17-1.50]). Starting distance working was also associated with incident depression (OR = 1.27 [1.08-1.48]).

LIMITATION

A cross-sectional design was used.

CONCLUSION

The consequences of lockdown on depression may vary depending on living conditions and changes in professional activity, including distance working. These results could help to better identify vulnerable people to promote mental health.

Comparison of Depression and Anxiety Following Self-reported COVID-19-Like Symptoms vs SARS-CoV-2 Seropositivity in France

Importance

The long-term consequences of COVID-19 on mental health are a critical issue given the number of people infected with SARS-CoV-2 worldwide since the beginning of the pandemic.

Objective

To investigate the associations between self-reported COVID-19-like symptoms or SARS-CoV-2 seropositivity and subsequent depression or anxiety.

Design, Setting, and Participants

This propensity score-matched cohort study began in May 2020, with follow-ups in November 2020 and July 2021. The study used data from a large, randomly selected, national population-based cohort from France, the EpiCoV (Epidémiologie et Conditions de Vie) study. Of 85 074 individuals 15 years or older who completed the questionnaires at the 3 collection times, 28 568 were excluded because they did not return a blood sample for serologic testing, 1994 because of missing data on outcomes or exposures, and 9252 to respect the temporal sequence (exposure must precede the outcome).

Exposures

Propensity scores based on various socioeconomic, lifestyle, and health variables were computed to match participants who experienced COVID-19-like symptoms between February and November 2020 or showed SARS-CoV-2 seropositivity in November 2020.

Main Outcomes and Measures

Logistic regression models were used to estimate associations between these occurrences and depression or anxiety assessed in July 2021 using the Patient Health Questionnaire 9-item and Generalized Anxiety Disorder 7-item scales, respectively.

Results

Among the 45 260 included participants (mean [SD] age, 51.1 [18.9] years; 52.4% women; 8.0% with depression and 5.3% with anxiety in July 2021), COVID-19-like symptoms were associated with subsequent depression (adjusted odds ratio, 1.70; 95% CI, 1.45-1.99) and anxiety (adjusted OR, 1.57; 95% CI, 1.29-1.92), whereas SARS-CoV-2 seropositivity was not. Furthermore, COVID-19-like symptoms, but not anosmia or dysgeusia alone, were associated with subsequent depression and anxiety in both the seropositive and seronegative subgroups.

Conclusions and Relevance

In this cohort study of more than 45 000 individuals drawn from the French general population, SARS-CoV-2 infection was not found as a risk factor of subsequent depression or anxiety. Moreover, self-reported COVID-19-like symptoms were associated with depression and anxiety assessed at least 8 months later in both seropositive and seronegative subgroups, suggesting that factors other than SARS-CoV-2 infection are implied in this association.

Pathways between Risk/Protective Factors and Maternal Postnatal Depressive Symptoms: The ELFE Cohort

OBJECTIVE

The risk factors for postnatal depressive symptoms (PNDS) are numerous, but little is known about the protective factors or the interactions between different exposures. The present study explored the pathways between maternal, infant and parenthood vulnerabilities or risk/protective factors and PNDS at 2 months postpartum (PP) in a large sample of women from the general population.

METHODS

We used data from the French ELFE cohort, a nationally representative cohort of children followed-up from birth. The available information about vulnerabilities or risk/protective factors for PNDS was collected during the maternity ward stay (mother or medical records) and at 2 months PP (mother by phone). PNDS were evaluated with the Edinburgh Postnatal Depression Scale (EPDS) at 2 months. A measurement model was built based on the psychosocial model for PNDS of Milgrom and colleagues using exploratory factor analysis. The Structural Equation Model was used to investigate the pathways between vulnerability, risk/protective factors and PNDS at 2 months PP.

RESULTS

In the study sample (n = 11,583), a lack of a partner's perceived antenatal emotional support, consultation with a mental health specialist before pregnancy, family financial difficulties, prenatal psychological distress and a difficult pregnancy experience were directly associated with the severity of maternal PNDS at 2 months PP, as well as lack of perceived postnatal support. Family financial difficulties and consultation with a mental health specialist before pregnancy were also indirectly associated with the intensity of PNDS through a lack of perceived antenatal emotional support, a difficult pregnancy experience, prenatal psychological distress and a lack of perceived postnatal support. Regarding infant and parenthood characteristics, infant self-regulation difficulties, maternal difficulty in understanding infant crying and infant hospitalisation were directly associated with PNDS severity at 2 months PP, while maternal difficulty in understanding an infant's cries was also indirectly associated with infant self-regulation difficulties.

CONCLUSIONS

Perinatal professional support should begin antenatally and target the couple's prenatal functioning, with particular attention to women presenting a history of psychiatric disorders, especially those of low socioeconomic status. After delivery, addressing infant and parenthood characteristics is also recommended.

COVID-19 and common mental health symptoms in the early phase of the pandemic: An umbrella review of the evidence

BACKGROUND

There remains uncertainty about the impact of the Coronavirus Disease 2019 (COVID-19) pandemic on mental health. This umbrella review provides a comprehensive overview of the association between the pandemic and common mental disorders. We qualitatively summarized evidence from reviews with meta-analyses of individual study-data in the general population, healthcare workers, and specific at-risk populations.

METHODS AND FINDINGS

A systematic search was carried out in 5 databases for peer-reviewed systematic reviews with meta-analyses of prevalence of depression, anxiety, and post-traumatic stress disorder (PTSD) symptoms during the pandemic published between December 31, 2019 until August 12, 2022. We identified 123 reviews of which 7 provided standardized mean differences (SMDs) either from longitudinal pre- to during pandemic study-data or from cross-sectional study-data compared to matched pre-pandemic data. Methodological quality rated with the Assessment of Multiple Systematic Reviews checklist scores (AMSTAR 2) instrument was generally low to moderate. Small but significant increases of depression, anxiety, and/or general mental health symptoms were reported in the general population, in people with preexisting physical health conditions, and in children (3 reviews; SMDs ranged from 0.11 to 0.28). Mental health and depression symptoms significantly increased during periods of social restrictions (1 review; SMDs of 0.41 and 0.83, respectively) but anxiety symptoms did not (SMD: 0.26). Increases of depression symptoms were generally larger and longer-lasting during the pandemic (3 reviews; SMDs depression ranged from 0.16 to 0.23) than those of anxiety (2 reviews: SMDs 0.12 and 0.18). Females showed a significantly larger increase in anxiety symptoms than males (1 review: SMD 0.15). In healthcare workers, people with preexisting mental disorders, any patient group, children and adolescents, and in students, no significant differences from pre- to during pandemic were found (2 reviews; SMD's ranging from -0.16 to 0.48). In 116 reviews pooled cross-sectional prevalence rates of depression, anxiety, and PTSD symptoms ranged from 9% to 48% across populations. Although heterogeneity between studies was high and largely unexplained, assessment tools and cut-offs used, age, sex or gender, and COVID-19 exposure factors were found to be moderators in some reviews. The major limitations are the inability to quantify and explain the high heterogeneity across reviews included and the shortage of within-person data from multiple longitudinal studies.

CONCLUSIONS

A small but consistent deterioration of mental health and particularly depression during early pandemic and during social restrictions has been found in the general population and in people with chronic somatic disorders. Also, associations between mental health and the pandemic were stronger in females and younger age groups than in others. Explanatory individual-level, COVID-19 exposure, and time-course factors were scarce and showed inconsistencies across reviews. For policy and research, repeated assessments of mental health in population panels including vulnerable individuals are recommended to respond to current and future health crises.

Parents' depression and anxiety associated with hyperactivity-inattention and emotional symptoms in children during school closure due to COVID-19 in France

Several risk factors of children's mental health issues have been identified during the pandemic of COronaVIrus Disease first appeared in 2019 (COVID-19). This study aims to fill the knowledge gap regarding the association between parents' and children's mental health issues during the COVID-19 school closure in France. We conducted a cross-sectional analysis of data collected in the SAPRIS-ELFE study during the COVID-19 pandemic in France. Using multinomial logistic regressions, we estimated associations between parents' and children's mental health issues. Symptoms of anxiety were assessed by the General Anxiety Disorder-7 (GAD-7) and depression by the Patient Health Questionnaire-9 (PHQ-9) for the parents. Hyperactivity/inattention and emotional symptoms in children were assessed by the Strengths and Difficulties Questionnaire (SDQ). The sample included 3496 children aged 8 to 9 years, of whom 50.0% were girls. During the school closure, 7.1% of responding parents had moderate to severe levels of anxiety and 6.7% had moderate to severe levels of depression. A total of 11.8% of the children had an abnormal hyperactivity/inattention score and 6.6% had an abnormal emotional symptoms score. In multivariate regression models, parental moderate to severe level of anxiety and moderate to severe level of depression were associated with abnormal hyperactivity-inattention score (adjusted Odds Ratio (aOR) 3.31; 95% Confidence Interval (CI) 2.33-4.70 and aOR 4.65; 95% CI 3.27-6.59, respectively) and abnormal emotional symptoms score in children (aOR 3.58; 95% CI 2.33-5.49 and aOR 3.78; 95 CI 2.47-5.78 respectively). Children whose parents have symptoms of anxiety and/or depression have an increased likelihood of symptoms of hyperactivity/inattention and emotional symptoms during school closures in France due to COVID-19. Our findings suggest that public health initiatives should target parents and children to limit the impact of such crises on their mental health issues.

Risk of SARS-CoV-2 infection, severe COVID-19 illness and COVID-19 mortality in people with pre-existing mental disorders: an umbrella review

INTRODUCTION

The COVID-19 pandemic has posed a serious health risk, especially in vulnerable populations. Even before the pandemic, people with mental disorders had worse physical health outcomes compared to the general population. This umbrella review investigated whether having a pre-pandemic mental disorder was associated with worse physical health outcomes due to the COVID-19 pandemic.

METHODS

Following a pre-registered protocol available on the Open Science Framework platform, we searched Ovid MEDLINE All, Embase (Ovid), PsycINFO (Ovid), CINAHL, and Web of Science up to the 6th of October 2021 for systematic reviews on the impact of COVID-19 on people with pre-existing mental disorders. The following outcomes were considered: risk of contracting the SARS-CoV-2 infection, risk of severe illness, COVID-19 related mortality risk, risk of long-term physical symptoms after COVID-19. For meta-analyses, we considered adjusted odds ratio (OR) as effect size measure. Screening, data extraction and quality assessment with the AMSTAR 2 tool have been done in parallel and duplicate.

RESULTS

We included five meta-analyses and four narrative reviews. The meta-analyses reported that people with any mental disorder had an increased risk of SARS-CoV-2 infection (OR: 1.71, 95% CI 1.09-2.69), severe illness course (OR from 1.32 to 1.77, 95%CI between 1.19-1.46 and 1.29-2.42, respectively) and COVID-19 related mortality (OR from 1.38 to 1.52, 95%CI between 1.15-1.65 and 1.20-1.93, respectively) as compared to the general population. People with anxiety disorders had an increased risk of SAR-CoV-2 infection, but not increased mortality. People with mood and schizophrenia spectrum disorders had an increased COVID-19 related mortality but without evidence of increased risk of severe COVID-19 illness. Narrative reviews were consistent with findings from the meta-analyses.

DISCUSSION AND CONCLUSIONS

As compared to the general population, there is strong evidence showing that people with pre-existing mental disorders suffered from worse physical health outcomes due to the COVID-19 pandemic and may therefore be considered a risk group similar to people with underlying physical conditions. Factors likely involved include living accommodations with barriers to social distancing, cardiovascular comorbidities, psychotropic medications and difficulties in accessing high-intensity medical care.

Evolution of smoking rates among immigrants in France in the context of comprehensive tobacco control measures, and a decrease in the overall prevalence

BACKGROUND

The evolution of smoking rates according to migrant status has not been examined in France, despite a recent reduction in overall smoking rates.

METHODS

DePICT is a two waves (2016: n = 4356; 2017: n = 4114) nationwide telephone survey, representative of the French adult population. We compared smoking-related behaviors before and after implementation of tobacco-control measures (2017), according to the geographical region of birth.

RESULTS

Compared to 2016, individuals originating from Africa or the Middle East had a slightly higher smoking prevalence in 2017 (34.7% vs 31.3%), despite a higher intention to quit or attempt in the preceding year (adjusted OR(ORa) = 2.72[1.90; 3.90]) compared to non-immigrants. They were also less likely to experience an unsuccessful quit attempt (ORa = 1.76[1.18; 2.62]).

CONCLUSION

Tobacco-control measures could have widened smoking inequalities related to migrant status. The evolution of smoking-related behaviors among immigrants should be examined when studying the long-term effects of such policies.

Psychosocial working conditions and sickness absence among younger employees in Denmark: a register-based cohort study using job exposure matrices

OBJECTIVE

Previous literature has established associations between psychosocial working conditions and sickness absence (SA), but only few studies have examined associations among younger employees. This study aimed to investigate associations between psychosocial working conditions and SA among employees, aged 15-30 years, who entered the labor market in Denmark between 2010 and 2018.

METHOD

We followed 301 185 younger employees in registers for on average 2.6 years. Using job exposure matrices, we assessed job insecurity, quantitative demands, decision authority, job strain, emotional demands, and work-related physical violence. Adjusted rate ratios of SA spells of any length were estimated for women and men separately with Poisson models.

RESULTS

Among women, employment in occupations with high quantitative demands, low decision authority, high job strain, high emotional demands, or high work-related physical violence was associated with higher rates of SA. Being employed in occupations with high versus low emotional demands showed the strongest association with SA, with a rate ratio of 1.44 [95% confidence interval (CI) 1.41-1.47]. Among men, being employed in occupations with low decision authority showed the strongest association with SA (1.34, 95% CI 1.31-1.37), whereas occupations with high quantitative demands, high job strain, and high emotional demands were associated with lower rates of SA.

CONCLUSION

We found that several psychosocial working conditions were associated with SA spells of any length. Associations with SA spells of any length resemble associations with long-term SA, suggesting that results from previous studies on long-term SA may be generalizable to all lengths of SA among younger employees.

Maternal tobacco smoking during pregnancy and children's emotional and behavioural trajectories : The EDEN mother-child birth cohort study

INTRODUCTION

The nature of the relationship between maternal tobacco smoking during pregnancy and the occurrence of children's behavioural problems is still a matter of controversy. We tested this association using data collected among a sample of pregnant women and their offspring followed from birth to early adolescence (age 12 years), accounting for multiple parent, child, and family characteristics.

METHODS

Data come from 1424 mother-child pairs participating in the EDEN mother-child cohort in France. Using repeated measures (3, 5.5, 8 and 11.5 years) of the mother-reported Strengths and Difficulties Questionnaire, we estimated trajectories of children's emotional and behavioural difficulties. Two aspects of maternal smoking were studied: the timing (non-smoker, smoking during the periconceptional period or throughout pregnancy) and the level of use (cigarettes/day) during the first trimester of pregnancy. Robust Poisson regression models controlled for confounding factors including maternal mental health and socioeconomic characteristics using propensity scores with the overlap weighting technique.

RESULTS

Contrary to bivariate analyses, in propensity score-controlled regression models, maternal smoking throughout pregnancy was no longer significantly associated with offspring emotional or behavioural difficulties. Maternal heavy smoking (≥10cigarettes/day) remained significantly associated with intermediate levels of conduct problems (RR 1.25 95%CI 1.19-1.31).

CONCLUSION

The association between maternal smoking in pregnancy and offspring emotional and behavioural difficulties appears to be largely explained by women's other characteristics. However, maternal heavy smoking appears to be related to offspring behavioural difficulties beyond the role of confounding characteristics.

IMPLICATIONS

The relationship between maternal smoking during pregnancy (in 2 modalities: timing and level of smoking) and behavioural difficulties in children is still a matter of debate. While the relationship between any maternal tobacco use and offspring behavioural difficulties appears to be largely explained by confounding factors, heavy maternal smoking in the first trimester of pregnancy seems to be associated with offspring behavioural difficulties beyond the socioeconomic and mental health characteristics transmitted across generations.

Suicidal ideation following self-reported COVID-19-like symptoms or serology-confirmed SARS-CoV-2 infection in France: A propensity score weighted analysis from a cohort study

BACKGROUND

A higher risk of suicidal ideation associated with self-report of Coronavirus Disease 2019 (COVID-19)-like symptoms or COVID-19 infection has been observed in cross-sectional studies, but evidence from longitudinal studies remains limited. The aims of this study were 2-fold: (1) to explore if self-reported COVID-19-like symptoms in 2020 were associated with suicidal ideation in 2021; (2) to explore if the association also existed when using a biological marker of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection in 2020.

METHODS AND FINDINGS

A total of 52,050 participants from the French EpiCov cohort were included (median follow-up time = 13.7 months). In terms of demographics, 53.84% were women, 60.92% were over 45 years old, 82.01% were born in mainland France from parents born in mainland France, and 59.38% completed high school. COVID-19-like symptoms were defined as participant report of a sudden loss of taste/smell or fever alongside cough, shortness of breath, or chest oppression, between February and November 2020. Symptoms were self-reported at baseline in May 2020 and at the first follow-up in Autumn 2020. Serology-confirmed SARS-CoV-2 infection in 2020 was derived from Spike protein ELISA test screening in dried-blood-spot samples. Samples were collected from October 2020 to March 2021, with 94.4% collected in 2020. Suicidal ideation since December 2020 was self-reported at the second follow-up in Summer 2021. Associations of self-reported COVID-19-like symptoms and serology-confirmed SARS-CoV-2 infection in 2020 with suicidal ideation in 2021 were ascertained using modified Poisson regression models, weighted by inverse probability weights computed from propensity scores. Among the 52,050 participants, 1.68% [1.54% to 1.82%] reported suicidal ideation in 2021, 9.57% [9.24% to 9.90%] had a serology-confirmed SARS-CoV-2 infection in 2020, and 13.23% [12.86% to 13.61%] reported COVID-19-like symptoms in 2020. Self-reported COVID-19-like symptoms in 2020 were associated with higher risks of later suicidal ideation in 2021 (Relative Riskipw [95% CI] = 1.43 [1.20 to 1.69]), while serology-confirmed SARS-CoV-2 infection in 2020 was not (RRipw = 0.89 [0.70 to 1.13]). Limitations of this study include the use of a single question to assess suicidal ideation, the use of self-reported history of mental health disorders, and limited generalizability due to attrition bias.

CONCLUSIONS

Self-reported COVID-19-like symptoms in 2020, but not serology-confirmed SARS-CoV-2 infection in 2020, were associated with a higher risk of subsequent suicidal ideation in 2021. The exact role of SARS-CoV-2 infection with respect to suicide risk has yet to be clarified. Including mental health resources in COVID-19-related settings could encourage symptomatic individuals to care for their mental health and limit suicidal ideation to emerge or worsen.

Paternity leave uptake and parental post-partum depression: findings from the ELFE cohort study

BACKGROUND

Several countries are expanding their paternity leave policies, which can have positive effects on parental mental health. We examined whether 2 weeks of paid paternity leave are associated with post-partum depression in mothers and fathers at 2 months after the birth of their child.

METHODS

We used data from the Etude Longitudinale Française depuis l'Enfance (ELFE) cohort study. Participating mothers gave birth in 2011 in a representative sample of 320 maternity hospitals in mainland France. Inclusion criteria were single or twin livebirths born after at least 33 weeks' gestation; mother's age at least 18 years; no plans to leave metropolitan France within 3 years. Mothers were interviewed face-to-face shortly after the child's birth. Fathers and mothers were both interviewed by telephone 2 months after the child's birth, reporting whether the father had the right to paternity leave and if yes, if he had taken or intended to take it. We used the Edinburgh Postnatal Depression Scale to assess post-partum depression among fathers and mothers at 2 months. Logistic regression models, using survey-weighted data and adjusted for confounders using inverse probability weights, yielded odds ratios (ORs).

FINDINGS

We included 10 975 fathers and 13 075 mothers with reported information on paternity leave and post-partum depression at 2 months in the statistical analyses. Fathers had a median age of 32·6 years (IQR 36·9-22·6) and mothers had a median age of 30·5 years (34·0-27·1) at the time of the ELFE child's birth. The prevalence of depression in fathers according to paternity leave status was 4·5% among those who used paternity leave, 4·8% among those who intended to use paternity leave, and 5·7% among those who did not use paternity leave. For mothers, the prevalence of post-partum depression was 16·1% among those whose partner used paternity leave, 15·1% among those whose partner intended to use paternity leave, and 15·3% among those whose partner did not use paternity leave. Fathers who took paternity leave had reduced odds of post-partum depression (OR 0·74 [95% CI 0·70-0·78]) as did fathers who intended to take paternity leave (0·76 [0·70-0·82]) compared with fathers who did not take paternity leave. However, we did not find such beneficial effects for mothers whose partners took (1·13 [1·05-1·20]) or intended to take paternity leave (1·02 [0·96-1·08]).

INTERPRETATION

Taking and intending to take 2-weeks' paid paternity leave was associated with a reduced likelihood of reporting post-partum depression in fathers. However, offering 2-weeks' paternity leave might place mothers at a greater risk of post-partum depression, suggesting that optimal length and timing of the leave, among other factors, need further investigation.

FUNDING

The French National Research Agency.

Prospective associations of lifestyle patterns in early childhood with socio-emotional and behavioural development and BMI: An outcome-wide analysis of the EDEN mother-child cohort

BACKGROUND

Children's energy balance-related behaviours (EBRB), comprising diet, screen time, physical activity, and sleep, combine into "lifestyle patterns", which may exert a synergistic effect on health. To date, studies investigating this synergy have primarily focused on obesity risk, without addressing other facets of health.

OBJECTIVES

To examine the prospective associations of preschoolers' lifestyle patterns with socio-emotional, behavioural, and body mass index (BMI) outcomes at 8 years.

METHODS

Participants were 876 children from the EDEN mother-child cohort. Three lifestyle patterns (unhealthy, healthy, and mixed) were previously identified at age 5, separately in boys and girls. At age 8, height and weight measures generated BMI z-scores while social-emotional and behavioural development was assessed by parents using the Strengths and Difficulties Questionnaire (SDQ). Drawing from the outcome-wide approach, sex- and outcome-specific adjusted linear regressions were fitted.

RESULTS

Boys' adherence to a healthy lifestyle pattern (combining a nutrient-dense diet and limited screen time) at 5 years was positively associated with prosocial behaviours (β = 0.14; 95% confidence interval [CI] 0.01, 0.26) and inversely related to hyperactivity-inattention symptoms (β = -0.12; 95% CI -0.23, -0.01) at 8 years. Girls' mixed lifestyle pattern (sugar or artificially sweetened beverages, high screen, physical activity and low sleep times) was associated with prosocial behaviours (β = 0.12; 95% CI 0.01, 0.23). There was no evidence of associations between lifestyle patterns and BMI z-scores.

CONCLUSIONS

Findings suggest synergistic benefits of engaging in a combination of optimal EBRBs, especially in boys, and support intervention efforts at preschool age to enhance some dimensions of their later socio-emotional and behavioural development.

Longitudinal impact of the COVID19 pandemic on mental health in a general population sample in France: Evidence from the COMET Study

BACKGROUND

To study the longitudinal impact of co-occurring mental health problems, and to identify vulnerable groups in need of mental health support during the COVID-19 pandemic.

METHODS

Analyses were based on data from 681 French participants in the international COVID-19 Mental Health Study, collected at four times (05/2020-04/2021). Symptoms of depression, anxiety and post-traumatic stress disorder (PTSD) were assessed using the Patient Health Questionnaire 9, the Generalized Anxiety Disorder-7 and the PTSD Check List for DSM-5. We performed k-means for longitudinal data to build trajectories of adults' depression, anxiety and PTSD symptoms and identify subgroups psychologically vulnerable. We then assessed whether mental health trajectories were predicted by lockdown regulations.

RESULTS

A high and a low cluster of mental health scores were identified. In both groups, mental health scores varied significantly across time. Levels of all mental health scores were lowest when COVID-19-related restrictions were lifted and highest when restrictions were in place, except for PTSD. No scores returned to the previous level or the initial level of mental health (p < 0.05). Participants with high levels of symptoms were characterized by younger age (OR: 0.98, 95 % CI: 0.97-0.99), prior history of mental disorders (OR: 3.46, 95 % CI: 2.07-5.82), experience of domestic violence (OR: 10.54, 95 % CI: 1.54-20.68) and medical issues (OR: 2.16, 95 % CI: 1.14-4.03).

LIMITATIONS

Pre-pandemic data were not available and the sample was recruited mainly by snowball sampling.

CONCLUSION

This study revealed subtle differences in the evolution of symptom trajectories during the first year of the Covid-19 pandemic, and highlighted several characteristics associated with the two clusters.

Remote mental health care interventions during the COVID-19 pandemic: An umbrella review

Mitigating the COVID-19 related disruptions in mental health care services is crucial in a time of increased mental health disorders. Numerous reviews have been conducted on the process of implementing technology-based mental health care during the pandemic. The research question of this umbrella review was to examine what the impact of COVID-19 was on access and delivery of mental health services and how mental health services have changed during the pandemic. A systematic search for systematic reviews and meta-analyses was conducted up to August 12, 2022, and 38 systematic reviews were identified. Main disruptions during COVID-19 were reduced access to outpatient mental health care and reduced admissions and earlier discharge from inpatient care. In response, synchronous telemental health tools such as videoconferencing were used to provide remote care similar to pre-COVID care, and to a lesser extent asynchronous virtual mental health tools such as apps. Implementation of synchronous tools were facilitated by time-efficiency and flexibility during the pandemic but there was a lack of accessibility for specific vulnerable populations. Main barriers among practitioners and patients to use digital mental health tools were poor technological literacy, particularly when preexisting inequalities existed, and beliefs about reduced therapeutic alliance particularly in case of severe mental disorders. Absence of organizational support for technological implementation of digital mental health interventions due to inadequate IT infrastructure, lack of funding, as well as lack of privacy and safety, challenged implementation during COVID-19. Reviews were of low to moderate quality, covered heterogeneously designed primary studies and lacked findings of implementation in low- and middle-income countries. These gaps in the evidence were particularly prevalent in studies conducted early in the pandemic. This umbrella review shows that during the COVID-19 pandemic, practitioners and mental health care institutions mainly used synchronous telemental health tools, and to a lesser degree asynchronous tools to enable continued access to mental health care for patients. Numerous barriers to these tools were identified, and call for further improvements. In addition, more high quality research into comparative effectiveness and working mechanisms may improve scalability of mental health care in general and in future infectious disease outbreaks.