Temporal changes in the risk of six-month post-covid symptoms: a national population-based cohort study.

It is unclear how the risk of post-covid symptoms evolved during the pandemic, especially before the spread of Severe Acute Respiratory Syndrome Coronavirus 2 variants and the availability of vaccines. We used modified Poisson regressions to compare the risk of six-month post-covid symptoms and their associated risk factors according to the period of first acute covid: during the French first (March-May 2020) or second (September-November 2020) wave. Non-response weights and multiple imputation were used to handle missing data. Among participants aged 15 or more in a national population-based cohort, the risk of post-covid symptoms was 14.6% (95% CI: 13.9%, 15.3%) in March-May 2020, versus 7.0% (95% CI: 6.3%, 7.7%) in September-November 2020 (adjusted RR: 1.36, 95% CI: 1.20, 1.55). For both periods, the risk was higher in the presence of baseline physical condition(s), and it increased with the number of acute symptoms. During the first wave, the risk was also higher for women, in the presence of baseline mental condition(s), and it varied with educational level. In France in 2020, the risk of six-month post-covid symptoms was higher during the first than the second wave. This difference was observed before the spread of variants and the availability of vaccines.

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.

Parental mental health and reporting of their child's behaviour: measurement invariance of the French version of the parental strengths and difficulties questionnaire.

Symptomatic effects of mental disorders in parents could bias their reporting on their child's mental health. This study aimed to investigate the measurement invariance of the French version of the parental Strengths and Difficulties Questionnaire (SDQ) across parental mental health in a sample (N = 20,765) of parents of children aged 3 to 17 years in France. Confirmatory factor analysis (CFA) and Exploratory Structural Equation Modelling (ESEM) were used to evaluate the fit of three known alternative SDQ factor structures (five, three, or second-order factor structures). Invariance was tested across parental mental health (present anxiety and depressive symptoms, psychiatric history) and across socio-demographic characteristics (child's age, child's gender, parent's gender, parent's educational level). CFA models showed a poor fit, while all ESEM models achieved acceptable or good fit, with the five-factor model presenting the best fit. Invariance was observed for all characteristics tested, indicating that the SDQ can be used to study the links between parental mental health and their child's mental health without bias. However, ESEM showed that the hyperactivity/inattention and conduct problems dimensions were not well differentiated in the French version of the SDQ.

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.

Enrichment of infant formula with long-chain polyunsaturated fatty acids and risk of infection and allergy in the nationwide ELFE birth cohort.

BACKGROUND: The new European regulations require the enrichment of formulas with docosahexaenoic acid (DHA) because of the positive effects of long-chain polyunsaturated fatty acids (LCPUFAs) on neurodevelopment and visual acuity. In this observational study, we aimed to evaluate whether the consumption of LCPUFA-enriched formula was associated with the risk of infection and allergy in early childhood. METHODS: Analyses involved data from 8389 formula-fed infants from the ELFE birth cohort. Formula enrichment was identified from the list of ingredients of the formula consumed at 2 months. Infections (gastrointestinal, lower respiratory tract [LRTI], upper respiratory tract) and allergies (wheezing, itchy rash, asthma medication, food allergy) from age 2 months to 5.5 years were reported by parents during follow-up surveys. Multivariable logistic regression models were used to assess associations between the consumption of LCPUFA-enriched formula and the risk of infection and allergy. RESULTS: Among formula-fed infants at 2 months, 36% consumed formula enriched with DHA and arachidonic acid (ARA), and 11% consumed formula additionally enriched with eicosapentaenoic acid (EPA). Enriched formula consumption was not associated with infection or allergy, except for an association between consumption of DHA/ARA/EPA-enriched formula and lower use of asthma medications. Furthermore, as compared with non-DHA/ARA/EPA-enriched formula, consumption of formula with high EPA content (≥3.2 mg/100 kcal) was related to lower risk of LRTI and lower use of asthma medications. CONCLUSION: This study suggests that consumption of DHA/ARA/EPA-enriched formula (especially those with high EPA content) is associated with a lower risk of LRTI and lower use of asthma medications.

Enrichment of Formula in Probiotics or Prebiotics and Risk of Infection and Allergic Diseases up to Age 5.5 Years in the Nationwide Etude Longitudinale Française depuis l'Enfance (ELFE) Cohort.

BACKGROUND: An increasing number of infant and follow-on formulas are enriched with probiotics and/or prebiotics; however, evidence for health effects of such enrichment in early childhood remains inconclusive. OBJECTIVES: The present study aimed to assess whether the consumption of formula enriched with probiotics or prebiotics was associated with the risk of infection and allergic diseases in early childhood. METHODS: Analyses involved data for 8389 formula-fed children from the Etude Longitudinale Française depuis l'Enfance (ELFE) cohort. Enrichment of the formula with probiotics or prebiotics that was consumed from the age of 2-10 mo was identified by the formula ingredient list. Lower respiratory tract infection (LRTI), upper respiratory tract infection (URTI), gastrointestinal infection, wheezing, asthma, food allergy, and itchy rash were prospectively reported by parents up to the age of 5.5 y. Adjusted logistic regression models were used to assess associations between the consumption of enriched formula and risk of infection and allergic diseases. RESULTS: Aged 2 mo, more than half of formula-fed infants consumed the probiotic-enriched formula and only 1 in 10 consumed the prebiotic-enriched formula. Consumption of the Bifidobacterium lactis-enriched formula at 2 mo was associated with a lower risk of LRTI [OR (95% CI) = 0.84 (0.73-0.96)]. Consumption of the Bifidobacterium breve-enriched formula up to 6 mo was associated with a higher risk of LRTI [OR (95% CI) = 1.75 (1.29-2.38)] and asthma [OR (95% CI) = 1.95 (1.28-2.97)], whereas its consumption from 6 to 10 mo was associated with a lower risk of LRTI [OR (95% CI) = 0.64 (0.48-0.86)] and asthma [OR (95% CI) = 0.59 (0.40-0.88)]. Moreover, the consumption of Streptococcus thermophilus from 6 to 10 mo was associated with a higher risk of asthma [OR (95% CI) = 1.84 (1.29-2.63)]. No significant association was found for gastrointestinal infection, food allergy, and itchy rash. Overall, the consumption of prebiotic-enriched formula was not significantly associated with infection and allergy risk. CONCLUSIONS: Associations between the consumption of probiotic-enriched formula and risk of respiratory symptoms differ according to the strain considered and consumption period. Further well-designed studies are needed to confirm these results.

Enrichment of Formula in Probiotics or Prebiotics and Risk of Infection and Allergic Diseases up to Age 5.5 Years in the Nationwide Etude Longitudinale Française depuis l'Enfance (ELFE) Cohort.

BACKGROUND: An increasing number of infant and follow-on formulas are enriched with probiotics and/or prebiotics; however, evidence for health effects of such enrichment in early childhood remains inconclusive. OBJECTIVES: The present study aimed to assess whether the consumption of formula enriched with probiotics or prebiotics was associated with the risk of infection and allergic diseases in early childhood. METHODS: Analyses involved data for 8389 formula-fed children from the Etude Longitudinale Française depuis l'Enfance (ELFE) cohort. Enrichment of the formula with probiotics or prebiotics that was consumed from the age of 2-10 mo was identified by the formula ingredient list. Lower respiratory tract infection (LRTI), upper respiratory tract infection (URTI), gastrointestinal infection, wheezing, asthma, food allergy, and itchy rash were prospectively reported by parents up to the age of 5.5 y. Adjusted logistic regression models were used to assess associations between the consumption of enriched formula and risk of infection and allergic diseases. RESULTS: Aged 2 mo, more than half of formula-fed infants consumed the probiotic-enriched formula and only 1 in 10 consumed the prebiotic-enriched formula. Consumption of the Bifidobacterium lactis-enriched formula at 2 mo was associated with a lower risk of LRTI [OR (95% CI) = 0.84 (0.73-0.96)]. Consumption of the Bifidobacterium breve-enriched formula up to 6 mo was associated with a higher risk of LRTI [OR (95% CI) = 1.75 (1.29-2.38)] and asthma [OR (95% CI) = 1.95 (1.28-2.97)], whereas its consumption from 6 to 10 mo was associated with a lower risk of LRTI [OR (95% CI) = 0.64 (0.48-0.86)] and asthma [OR (95% CI) = 0.59 (0.40-0.88)]. Moreover, the consumption of Streptococcus thermophilus from 6 to 10 mo was associated with a higher risk of asthma [OR (95% CI) = 1.84 (1.29-2.63)]. No significant association was found for gastrointestinal infection, food allergy, and itchy rash. Overall, the consumption of prebiotic-enriched formula was not significantly associated with infection and allergy risk. CONCLUSIONS: Associations between the consumption of probiotic-enriched formula and risk of respiratory symptoms differ according to the strain considered and consumption period. Further well-designed studies are needed to confirm these results.

LC-PUFA enrichment in infant formula and neurodevelopment up to age 3.5 years in the French nationwide ELFE birth cohort.

PURPOSE: For decades, consistent associations between breastfeeding and children's neurodevelopment have been attributed to breastmilk content in long-chain polyunsaturated fatty acids (LC-PUFAs). However, the beneficial effect of LC-PUFA enrichment of infant formula on neurodevelopment remains controversial. This study examined the association of LC-PUFA enrichment of infant formulas with neurodevelopment up to age 3.5 years. METHODS: Analyses were based on 9372 children from the French nationwide ELFE birth cohort. Monthly from 2 to 10 months, parents declared their infant's feeding mode, including breastfeeding and the name of the infant formula, which allowed for identifying formulas enriched in arachidonic (ARA), eicosapentaenoic (EPA) and/or docosahexaenoic (DHA) acids. Neurodevelopment was assessed at age 1 and 3.5 years with the Child Development Inventory (CDI-1 and CDI-3.5); at 2 years with the MacArthur-Bates Communicative Development Inventories (MB-2); and at 3.5 years with the Picture Similarities subtest of the British Ability Scale (BAS-3.5). Associations were assessed by linear regression adjusted for any breastfeeding duration and main confounding factors, including socioeconomic characteristics. RESULTS: One-third of formula-fed infants consumed LC-PUFA-enriched formulas. Most of these formulas were enriched in both DHA and ARA, and about 10% of infants consumed formula further enriched in EPA. LC-PUFA enrichment of infant formula was not associated with neurodevelopmental scores at age 1 (CDI-1, - 0.16 [- 0.39, 0.07]), age 2 (MB-2, 0.78 [- 0.33, 1.89]), or age 3.5 (CDI-3.5, - 0.05 [- 0.27, 0.17]; BAS-3.5, - 0.93 [- 2.85, 0.98]). CONCLUSION: In the ELFE study, LC-PUFA enrichment of infant formula was not associated with neurodevelopmental scores up to 3.5 years.

Resilience of people with chronic medical conditions during the COVID-19 pandemic: a 1-year longitudinal prospective survey.

BACKGROUNDS: Individuals with chronic medical conditions are considered highly exposed to COVID-19 pandemic stress, but emerging evidence is demonstrating that resilience is common even among them. We aimed at identifying sustained resilient outcomes and their predictors in chronically ill people during the first year of the pandemic. METHODS: This international 4-wave 1-year longitudinal online survey included items on socio-demographic characteristics, economic and living situation, lifestyle and habits, pandemic-related issues, and history of mental disorders. Adherence to and approval of imposed restrictions, trust in governments and in scientific community during the pandemic were also investigated. The following tools were administered: the Patient Health Questionnaire, the Generalized Anxiety Disorder scale, the PTSD Checklist DSM-5, the Oslo Social Support Scale, the Padua Inventory, and the Portrait Values Questionnaire. RESULTS: One thousand fifty-two individuals reporting a chronic condition out of 8011 total participants from 13 countries were included in the study, and 965 had data available for the final model. The estimated probability of being "sustained-resilient" was 34%. Older male individuals, participants employed before and during the pandemic or with perceived social support were more likely to belong to the sustained-resilience group. Loneliness, a previous mental disorder, high hedonism, fear of COVID-19 contamination, concern for the health of loved ones, and non-approving pandemic restrictions were predictors of not-resilient outcomes in our sample. CONCLUSIONS: We found similarities and differences from established predictors of resilience and identified some new ones specific to pandemics. Further investigation is warranted and could inform the design of resilience-building interventions in people with chronic diseases.

Characteristics associated with feeding organic foods during complementary feeding: the nationwide Étude Longitudinale Française depuis l'Enfance (ELFE) birth cohort.

Organic food consumption and its effects on health remain understudied in adults and in children. The aim of this study was to describe family characteristics associated with feeding infants organic foods during the complementary feeding period. The analysis included 9764 children from the French Étude Longitudinale Française depuis l'Enfance (ELFE) birth cohort. In addition to telephone interviews conducted at 2, 12 and 24 months, a monthly questionnaire about milk feeding and complementary foods (including organic foods) was completed by parents between 3 and 10 months. Associations between family characteristics and feeding with organic foods during complementary feeding were analysed by multivariable multinomial logistic regression. Overall, 51 % of infants never consumed organic food during the complementary feeding period (up to 10 months), 24 % sometimes, 15 % often and 9 % always or almost always. As compared with infants never fed organic foods, those 'often' or 'always' fed organic foods were born to older mothers, with higher education level or family income, and lower pre-pregnancy BMI. As compared with never-smoking women, women who had stopped smoking before pregnancy were more likely to feed their infant organic foods. Feeding with organic foods was also related to long breast-feeding duration and later introduction to complementary foods. To conclude, associations between feeding with organic foods and family socio-economic position as well as infant feeding practices need to be considered when studying the impact of organic foods on children's health and development.

Infant feeding practices and sleep at 1 year of age in the nationwide ELFE cohort.

Sleep problems reported by parents affect 20% to 30% of infants. Few studies focused on the longitudinal association between infant feeding practices and sleep, especially in France. Analyses were based on 8,696 infants from the French national birth cohort ELFE. Collection of feeding practices from birth to 10 months allowed for the identification of trajectories of use of baby cereals and thickened formula by group-based trajectory modelling and calculation of duration of any breastfeeding (BF) and age at complementary feeding introduction (CFI) excluding baby cereals. Total sleep duration (TSD), night waking (NW) and sleep onset difficulties (SOD) were reported at age 1. Associations between feeding and sleep were tested by multinomial logistic regressions. BF duration ≥6 months was associated with parent-reported frequent NW, SOD and TSD ≤ 12 h/24 h at age 1. For TSD and SOD, this association was no longer significant after accounting for parental sleep-related practices. Early use of baby cereals (≤5 months) was associated with poor sleep. Early CFI (<4 months) was associated with shorter TSD and SOD but not NW. Early use of thickened formula (only <6 months) was related to poor sleep at age 1 (NW and SOD), whereas late (around 6 months) use of thickened formula was associated with better sleep. BF duration ≥6 months was related to poor sleep at age 1 but not after adjustment on 1-year parental sleep-related practices except for NW. The use of baby cereals or early CFI was not related to better sleep at age 1.

Breastfeeding initiation or duration and longitudinal patterns of infections up to 2 years and skin rash and respiratory symptoms up to 8 years in the EDEN mother-child cohort.

This paper aimed to examine the effect of breastfeeding on longitudinal patterns of common infections up to 2 years and respiratory symptoms up to 8 years. To assess the incidence and reoccurrence of infections and allergic symptoms in the first years of life among 1,603 children from the EDEN mother-child cohort, distinct longitudinal patterns of infectious diseases as well as skin rash and respiratory symptoms were identified by group-based trajectory modelling. To characterize infections, we considered the parent-reported number of cold/nasopharyngitis and diarrhoea from birth to 12 months and otitis and bronchitis/bronchiolitis from birth to 2 years. To characterize allergy-related symptoms, we considered the parent-reported occurrence of wheezing and skin rash from 8 months to 8 years and asthma from 2 to 8 years. Then associations between breastfeeding and these longitudinal patterns were assessed through adjusted multinomial logistic regression. Compared with never-breastfed infants, ever-breastfed infants were at a lower risk of diarrhoea events in early infancy as well as infrequent events of bronchitis/bronchiolitis throughout infancy. Only predominant breastfeeding duration was related to frequent events of bronchitis/bronchiolitis and infrequent events of otitis. We found no significant protective effect of breastfeeding on longitudinal patterns of cold/nasopharyngitis, skin rash, or respiratory symptoms. For an infant population with a short breastfeeding duration, on average, our study confirmed a protective effect of breastfeeding on diarrhoea events in early infancy, infrequent bronchitis/bronchiolitis and, to a lesser extent, infrequent otitis events up to 2 years but not on other infections, skin rash, or respiratory symptoms4.

Infant feeding practices and sleep development in pre-schoolers from the EDEN mother-child cohort.

Sleep problems affect 20%-30% of toddlers and preschoolers. Few longitudinal studies focused on the impact of infant feeding practices on sleep. We aimed to study the associations between feeding practices up to 8 months and trajectories of sleep quantity or quality from 2 to 5-6 years. Analyses included 1,028 children from the EDEN mother-child cohort. Data were collected by self-administered questionnaires. Associations between feeding practices (breastfeeding, complementary feeding, use of thickened infant formula, night feeding) and sleep trajectories (sleep-onset difficulties, night waking, nighttime in bed) were analysed by multiple logistic regressions. Predominant breastfeeding for more than 4 months was associated with lower risk for belonging to the persistent sleep-onset difficulties trajectory. Night feeding at 4 months or at 2 years old was associated with higher risk for belonging to the persistent sleep-onset difficulties trajectory, and night feeding at 8 months was associated with higher risk for night waking and higher risk for short nighttime in bed. Early introduction (< 4 months) to complementary foods (excluding baby cereals) was related to lower risk for short nighttime in bed. Use of baby cereals or thickened infant formula was related neither to sleep quality nor to sleep quantity. In conclusion, infant feeding practices are associated with sleep trajectories in preschoolers, with notably a potential protective role of breastfeeding. Further researches are needed to clarify the mechanisms of these relationships.

Use of partially hydrolysed formula in infancy and incidence of eczema, respiratory symptoms or food allergies in toddlers from the ELFE cohort.

BACKGROUND AND OBJECTIVES: Partially hydrolyzed formulas (pHF) are recommended in non-breastfed infants with familial history of allergy to prevent allergy development. However, recent meta-analysis does not provide strong support for their protective effect. The present work assesses the links between 2-month infant formula use and the incidence of eczema, respiratory symptoms, or food allergies (FA) up to 2 years of age. METHODS: The nationwide ELFE birth cohort is a population-based study from mainland France. Infant feeding (breast milk only, partially hydrolyzed formula with [pHF-HA] or without a hypoallergenic label [pHF-non-HA], and non-hydrolyzed formula [Nhf]) was reported at 2 months. Eczema, FA, and respiratory symptoms such as wheezing and asthma were reported at 2 months, 1 year, and 2 years. Infants with prior FA at 2 months were excluded from analyses. RESULTS: Among 11 720 infants, those who received only breast milk at 2 months were at lower risk of eczema at 1 year than those who received nHF (OR[95% CI] = 0.78[0.65-0.94] in non-at-risk infants; 0.86[0.75-0.98] in at-risk infants). The use of pHF-HA, compared with nHF, at 2 months was related to higher risk of wheezing at 1 year in at-risk infants (1.68[1.24-2.28]) and higher risk of FA at 2 years both in non-at-risk infants (3.78[1.52-9.41]) and in at-risk infants (2.31[1.36-3.94]). CONCLUSIONS: In this nationwide study, pHF-HA use was not associated with a lower risk of any of the studied outcomes. Quite the reverse, it was associated with a higher risk of wheezing and FA. This should be confirmed in further studies.

Maternity or parental leave and breastfeeding duration: Results from the ELFE cohort.

Previous studies have shown a high level of noncompliance with recommendations on breastfeeding duration, especially in France. The objective was to describe the association between breastfeeding initiation and duration and the statutory duration of postnatal maternity leave, the gap between the end of legal maternity leave and the mother's return to work, and maternal working time during the first year post-partum. Analyses were based on 8,009 infants from the French nationwide ELFE cohort. We assessed the association with breastfeeding initiation by using logistic regression and, among breastfeeding women, with categories of breastfeeding duration by using multinomial logistic regression. Among primiparous women, both postponing return to work for at least 3 weeks after statutory postnatal maternity leave (as compared with returning to work at the end of the statutory period) and working less than full-time at 1 year post-partum (as compared with full-time) were related to higher prevalence of breastfeeding initiation. Among women giving birth to their first or second child, postponing the return to work until at least 15 weeks was related to a higher prevalence of long breastfeeding duration (at least 6 months) as compared with intermediate duration (3 to <6 months). Working part-time was also positively related to breastfeeding duration. Among women giving birth to their third child or more, working characteristics were less strongly related to breastfeeding duration. These results support extending maternity leave or working time arrangements to encourage initiation and longer duration of breastfeeding.

Use of infant formula in the ELFE study: The association with social and health-related factors.

Breastfeeding is recommended until 6 months of age, but a wide range of infant formula is available for nonbreastfed or partially breastfed infants. Our aim was to describe infant formula selection and to examine social- and health-related factors associated with this selection. Analyses were based on 13,291 infants from the French national birth cohort Etude Longitudinale Française depuis l'Enfance. Infant diet was assessed at Month 2 by phone interview and monthly from Months 3 to 10 via internet/paper questionnaires. Infant formulas were categorized in 6 groups: extensively or partially hydrolysed, regular with or without prebiotics/probiotics, and thickened with or without prebiotics/probiotics. Associations between type of infant formula used at 2 months and family or infant characteristics were assessed by multinomial logistic regressions. At Month 2, 58.1% of formula-fed infants were fed with formula enriched in prebiotics/probiotics, 31.5% with thickened formula, and 1.4% with extensively hydrolysed formula. The proportion of formula-fed infants increased regularly, but the type of infant formula used was fairly stable between 2 and 10 months. At Month 2, extensively hydrolysed formulas were more likely to be used in infants with diarrhoea or regurgitation problems. Partially hydrolysed formulas were more often used in families with high income, with a history of allergy, or with infants with regurgitation issues. Thickened formulas were used more with boys, preterm infants, infants with regurgitation issues, or in cases of early maternal return to work. The main factors related to the selection of infant formula were family and infant health-related ones.

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.

Substance Use Among Residents of Homeless Shelters During the COVID-19 Pandemic: Findings From France.

Objectives: To record the prevalence and risk factors of substance use amongst homeless persons during the COVID-19 pandemic. Methods: The ECHO study consisted in two independent cross-sectional waves of data collection in the regions of Paris, Lyon, and Strasbourg during the Spring of 2020 (n = 530) and 2021 (n = 319). Factors associated with substance use were explored using generalised logistic regression models. Results: The most prevalent substance used was tobacco (38%-43%), followed by alcohol (26%-34%). The use of both substances positively associated with each other, although risk factors varied depending on the substance. The only factors consistently associated with alcohol and tobacco use were being male, exposure to theft/assault and participants' region of origin. Whilst the rate of tobacco use was relatively stable between Spring 2020 and 2021, alcohol use was more common in 2021. Conclusion: These findings highlight a high prevalence of substance use amongst homeless persons. People experiencing homelessness face specific challenges in the context of the pandemic, alongside greater vulnerability to illness and low healthcare access, therefore the need to improve prevention and support services for substance abuse within this population is vital.

Labor market participation and depression during the COVID-19 pandemic among young adults (18 to 30 years): A nationally representative study in France.

Objective: To examine the relationship between young adults' labor force participation and depression in the context of the COVID-19 pandemic. Design setting participants: Data come from the nationally-representative EPICOV cohort study set up in France, and were collected in 2020 and 2021 (3 waves of online or telephone interviews: 02/05/2020-12/06/2020; 26/10/2020-14/12/2020; 24/06/2021-09/08/2021) among 2,217 participants aged 18-30 years. Participants with prior mental health disorder (n = 50) were excluded from the statistical analyses. Results: Using Generalized Estimating Equation (GEE) models controlled for participants' socio-demographic and health characteristics and weighted to be nationally-representative, we found that compared to young adults who were employed, those who were studying or unemployed were significantly more likely to experience depression assessed using the PHQ-9 (multivariable ORs, respectively: OR: 1.29, 95% CI 1.05-1.60 and OR: 1.50, 1.13-1.99). Stratifying the analyses by age, we observed that unemployment was more strongly associated with depression among participants 25-30 years than among those who were 18-24 years (multivariable ORs, respectively, 1.78, 95% CI 1.17-2.71 and 1.41, 95% CI 0.96-2.09). Being out of the labor force was, to the contrary, more significantly associated with depression among participants 18-24 years (multivariable OR: 1.71, 95% CI 1.04-2.82, vs. 1.00, 95% CI 0.53-1.87 among participants 25-30 years). Stratifying the analyses by sex, we found no significant differences in the relationships between labor market characteristics and depression (compared to participants who were employed, multivariable ORs associated with being a student: men: 1.33, 95% CI 1.01-1.76; women: 1.19, 95% CI 0.85-1.67, multivariable ORs associated with being unemployed: men: 1.60, 95% CI 1.04-2.45; women: 1.47, 95% CI 1.01-2.15). Conclusions and relevance: Our study shows that in addition to students, young adults who are unemployed also experience elevated levels of depression in the context of the COVID-19 pandemic. These two groups should be the focus of specific attention in terms of prevention and mental health treatment. Supporting employment could also be a propitious way of reducing the burden of the COVID-19 pandemic on the mental health of young adults.