Louise Séguin

Stress Pathways to Spontaneous Preterm Birth: The Role of Stressors, Psychological Distress, and Stress Hormones

The authors investigated a large number of stressors and measures of psychological distress in a multicenter, prospective cohort study of spontaneous preterm birth among 5,337 Montreal (Canada)-area women who delivered from October 1999 to April 2004. In addition, a nested case-control analysis (207 cases, 444 controls) was used to explore potential biologic pathways by analyzing maternal plasma corticotrophin-releasing hormone (CRH), placental histopathology, and (in a subset) maternal hair cortisol. Among the large number of stress and distress measures studied, only pregnancy-related anxiety was consistently and independently associated with spontaneous preterm birth (for values above the median, adjusted odds ratio = 1.8 (95% confidence interval: 1.3, 2.4)), with a dose-response relation across quartiles. The maternal plasma CRH concentration was significantly higher in cases than in controls in crude analyses but not after adjustment (for concentrations above the median, adjusted odds ratio = 1.1 (95% confidence interval: 0.8, 1.6)). In the subgroup (n = 117) of participants with a sufficient maternal hair sample, hair cortisol was positively associated with gestational age. Neither maternal plasma CRH, hair cortisol, nor placental histopathologic features of infection/inflammation, infarction, or maternal vasculopathy were significantly associated with pregnancy-related anxiety or any other stress or distress measure. The biologic pathways underlying stress-induced preterm birth remain poorly understood.

Sustained active transportation is associated with a favorable body mass index trajectory across the early school years: findings from the Quebec Longitudinal Study of Child Development birth cohort

OBJECTIVE To determine the extent to which active transportation (AT) to and from school is associated with changes in body mass index (BMI) from kindergarten (6-year-olds) through grade 2 (8-year-olds). METHODS The sample included 1170 children (50.4% of baseline participants) who were part of the Quebec Longitudinal Study of Child Development (QLSCD), a birth cohort established in 1998 in Quebec, Canada. Data were collected by trained interviewers using structured interviews and measuring height and weight in the home with the person most knowledgeable about the childs health. Relative weight was operationalized as age- and sex-adjusted BMI Z-scores. RESULTS Growth curve analyses showed that using AT to and from school both when in kindergarten and in grade 1 was predictive of a lower BMI Z-score (coeff=-0.18, SE=0.09, p=0.05) in grade 1. Using AT to and from school in kindergarten, grade 1, and grade 2 was predictive of a lower BMI Z-score (coeff=-0.30, SE=0.098, p=0.003) in grade 2. No other covariates were predictive of relative weight across time, although having an overweight or obese mother was associated with a BMI Z-score of 0.39 (SE=0.07, p<0.001) across all time points. CONCLUSION Sustained AT is associated with more healthful trajectories of BMI across the early school years.

Inherited thrombophilia and preeclampsia within a multicenter cohort: the Montreal Preeclampsia Study.

OBJECTIVE We sought to evaluate the association between inherited thrombophilia and preeclampsia. STUDY DESIGN From a multicenter cohort of 5337 pregnant women, we prospectively identified 113 women who developed preeclampsia and selected 443 control subjects who did not have preeclampsia or nonproteinuric gestational hypertension. Blood samples were tested for DNA polymorphisms affecting thrombophilia (factor V Leiden mutation, prothrombin G20210A mutation, methylenetetrahydrofolate reductase C677T polymorphism), homocysteine, and folate levels, and placentae underwent pathological evaluation. RESULTS Thrombophilia was present in 14% of patients and 21% of control subjects (adjusted logistic regression odds ratio, 0.6; 95% confidence interval, 0.3-1.3). Placental underperfusion was present in 63% of patients vs 46% of control subjects (P < .001) and was more frequent in women with folate levels in the lowest quartile (P = .04), but was not associated with thrombophilia. CONCLUSION We did not find evidence to support an association between inherited thrombophilia and increased risk of preeclampsia. Placental underperfusion is associated with preeclampsia, but this does not appear to be consequent to thrombophilia.

Self-rated health and postnatal depressive symptoms among immigrant mothers in Québec.

ABSTRACT Data from the Québec Longitudinal Study of Child Development were used to examine factors associated with postnatal depression and the links between self-rated health (SRH) and depressive symptoms in mothers 5 months after giving birth, according to immigration status. Postnatal depressive symptoms were measured using the 12-item Center for Epidemiologic Studies Depression Scale (CES-D). Immigrant mothers were classified according to their ethnocultural (majority or minority) group and compared with Canadian-born mothers. Logistic regression was used to evaluate the association between SRH and depressive symptoms. The prevalence of high depressive symptoms was larger among immigrants from minority groups (24.7%) than among immigrants from majority groups (8.3%) and Canadian-born mothers (11.2%). SRH was associated with depressive symptoms among Canadian-born mothers, but not among minority immigrant mothers. Canadian-born mothers integrated mental health into their assessment of overall health status, however, depressive symptoms among minority immigrant mothers were common, and their determinants warrant further research.

Impact of the 2008 Economic and Financial Crisis on Child Health : A Systematic Review

The aim of this study was to provide an overview of studies in which the impact of the 2008 economic crisis on child health was reported. Structured searches of PubMed, and ISI Web of Knowledge, were conducted. Quantitative and qualitative studies reporting health outcomes on children, published since 2007 and related to the 2008 economic crisis were included. Two reviewers independently assessed studies for inclusion. Data were synthesised as a narrative review. Five hundred and six titles and abstracts were reviewed, from which 22 studies were included. The risk of bias for quantitative studies was mixed while qualitative studies showed low risk of bias. An excess of 28,000–50,000 infant deaths in 2009 was estimated in sub-Saharan African countries, and increased infant mortality in Greece was reported. Increased price of foods was related to worsening nutrition habits in disadvantaged families worldwide. An increase in violence against children was reported in the U.S., and inequalities in health-related quality of life appeared in some countries. Most studies suggest that the economic crisis has harmed children’s health, and disproportionately affected the most vulnerable groups. There is an urgent need for further studies to monitor the child health effects of the global recession and to inform appropriate public policy responses.

Vasculopathic and thrombophilic risk factors for spontaneous preterm birth

BACKGROUND Mothers who give birth to preterm infants are at increased risk of mortality from coronary heart disease and stroke, but the biological pathways underlying these associations have not been explored. METHODS We carried out a case-control study nested in a large (n = 5337) prospective, multicentre cohort. All cohort women had an interview, examination and venipuncture at 24-26 weeks. Frozen plasma samples in spontaneous preterm births (n = 207) and 444 term controls were analysed for plasma homocysteine, folate, cholesterol (total, low-density lipoprotein and high-density lipoprotein) and thrombin-antithrombin (TAT) complexes. DNA was extracted and analysed for seven gene polymorphisms involved in thrombophilia or folate or homocysteine metabolism. Fresh placentas were fixed, stained and blindly assessed for histologic evidence of infarction and decidual vasculopathy. RESULTS High (above the median) plasma homocysteine and HDL cholesterol were significantly and independently associated with the risk of spontaneous preterm birth [adjusted odds ratios (OR)s = 1.9 (95% 1.1-3.3) and 0.5 (0.3-0.9), respectively]. A higher proportion of women with high homocysteine concentrations had decidual vasculopathy [(13.0 vs 6.8%; OR = 1.9 (1.1-3.5)], although the positive association between decidual vasculopathy and preterm birth did not achieve statistical significance [OR = 1.5 (0.9-2.7)]. No significant associations were observed with the DNA polymorphisms or with plasma TAT or folate levels. CONCLUSIONS Similar vasculopathic risk factors may underlie preterm birth and adult coronary heart disease and stroke.

Understanding the dimensions of socioeconomic status that influence toddlers’ health: unique impact of lack of money for basic needs in Quebec’s birth cohort

Study objectives: To examine the unique impact of financial difficulties as measured by a lack of money for basic needs on the occurrence of health problems between the ages of 17 and 29 months, controlling for mother’s level of education and neonatal health problems. Design and participants: Analyses were performed on the 29 month data of the Quebec longitudinal study of child development. This longitudinal study followed up a birth cohort annually. Interviews were conducted in the home with the mother in 98.8% of cases. This information was supplemented with data from birth records. At 29 months, the response rate was 94.2% of the initial sample (n = 1946). The main outcome measures were mothers’ report of acute health problems, asthma episodes, and hospitalisation as well as growth delay and a composite index of health problems (acute problems, asthma attack, growth delay). Main results: Children raised in a family experiencing a serious lack of money for basic needs during the preceding year were more likely to be reported by their mothers as presenting acute health problems, a growth delay, two or more health problems, and to have been hospitalised for the first time within the past few months as compared with babies living in a family not experiencing a lack of money for basic needs regardless of the mother’s level of education and of neonatal health problems. Conclusion: Financial difficulties as measured by a lack of money for basic needs have a significant and unique impact on toddlers’ health.

Duration of Poverty and Child Health in the Quebec Longitudinal Study of Child Development: Longitudinal Analysis of a Birth Cohort

OBJECTIVES. The objective of this study was to examine the relationship between duration of poverty and the health of preschool children in the Quebec Longitudinal Study of Child Development birth cohort. METHODS. Data from the Quebec Longitudinal Study of Child Development for 1950 children who were followed annually up to age 3 years were analyzed. Poverty was defined as having an income below the low-income cutoff from Statistics Canada. Five health indicators were examined: asthma attacks, infections, growth delay, a cumulative health-problems index, and maternal perception of the childs health. The association between duration of poverty and child health was explored with logistic regression modeling controlling for child and mother characteristics, including the mothers level of education, social support, and physical violence. RESULTS. In this birth cohort, 13.7% (268) 3-year-old children from the Quebec Longitudinal Study of Child Development experienced intermittent poverty since birth (1–2 episodes), and another 14.4% (280) experienced chronic poverty (3–4 episodes). Children from families with chronic poverty had more frequent asthma attacks and had a higher cumulative health-problems index score, whereas children with intermittent poverty were more often perceived to be in less than very good health by their mothers. These associations remained statistically significant when controlling for child and mother characteristics. No association was observed between duration of poverty and infections or growth delay. CONCLUSIONS. Chronic poverty affects a large number of children and has negative consequences for preschool childrens health, although universal health care is available. The effects of chronic poverty may vary according to different health indicators and the age of the child.

Mid-trimester maternal plasma cytokines and CRP as predictors of spontaneous preterm birth.

Most previous studies of maternal cytokines and preterm birth have analyzed immunologic biomarkers after the onset of labor or membrane rupture; fewer have examined the systemic (blood) immune response prior to labor onset. We carried out a case-control study nested in a large (n=5337) prospective, multi-center cohort. Cohort women had an interview, examination, and venipuncture at 24-26 weeks. Frozen plasma samples in women with spontaneous preterm birth (n=207) and approximately 2 term controls per case (n=444) were analyzed using Luminex multianalyte profiling technology. Fresh placentas were fixed, stained, and blindly assessed for histologic evidence of infection/inflammation, decidual vasculopathy, and infarction, and vaginal swabs were analyzed for bacterial vaginosis and fetal fibronectin concentration. High maternal matrix metalloproteinase-9 (MMP-9) concentration, but none of the other cytokines or C-reactive protein (CRP), was significantly associated with spontaneous preterm birth [adjusted OR=1.7 (1.1-2.4)] and showed a dose-response relation across quartiles. No association was observed, however, between maternal MMP-9 and placental infection/inflammation, bacterial vaginosis, or vaginal fetal fibronectin concentration. Our results require confirmation in future studies but suggest that a systemic immune response implicating MMP-9 may have an etiologic role in spontaneous preterm birth.

Understanding the determinants of active transportation to school among children: Evidence of environmental injustice from the Quebec longitudinal study of child development

PURPOSE To examine the combined influence of poverty and dangerousness of the neighborhood on active transportation (AT) to school among a cohort of children followed throughout the early school years. METHODS Growth curve modeling was used to identify determinants of AT to school among 710 children participating in the Quebec Longitudinal Study of Child Development from 2003 through 2006. Parent-reported dangerousness and pedestrian-vehicle collision data were merged with travel mode and health data. RESULTS At age 6 years, insufficient household income, having an older sibling, and living in a neighborhood that is not excellent for raising children, or characterized with high decay were predictive of greater likelihood of using AT and remained unchanged as children progressed from kindergarten through grade 2. CONCLUSION A public health concern is children experiencing environmental injustice. Since AT is most likely to be adopted by those living in poverty and because it is also associated with unsafe environments, some children are experiencing environmental injustice in relation to AT. Interventions may be implemented to reduce environmental injustice through improvements in road safety.