Birth and postnatal outcomes among infants of immigrant parents of different admission categories and parents born in Canada: a population-based retrospective study

BACKGROUND

Most studies of disparities in birth and postnatal outcomes by parental birthplace combine all immigrants into a single group. We sought to evaluate heterogeneity among immigrants in Canada by comparing birth and postnatal outcomes across different immigration categories.

METHODS

We conducted a population-based retrospective study using Statistics Canada data on live births and stillbirths (1993-2017) and infant deaths (1993-2018), linked to parental immigration data (1960-2017). We classified birthing parents as born in Canada, economic-class immigrants, family-class immigrants, or refugees, and evaluated differences in preterm births, small-for-gestational-age (SGA) and large-for-gestational-age (LGA) births, stillbirths, and infant deaths among singleton births by group.

RESULTS

Among 7 980 650 births, 1 715 050 (21.5%) were to immigrants, including 632 760 (36.9%) in the economic class, 853 540 (49.8%) in the family class, and 228 740 (13.4%) refugees. Compared with infants of Canadian-born birthing parents, infants of each of the 3 immigrant groups had higher risk of preterm birth, SGA birth, and stillbirth, but lower risk of LGA birth and neonatal death. Compared with infants of economic-class immigrants, infants of refugees had higher risk of early preterm birth (0.9% v. 0.8%, adjusted risk ratio [RR] 1.08, 95% confidence interval [CI] 1.01-1.15) and LGA birth (9.2% v. 7.5%, adjusted RR 1.12, 95% CI 1.10-1.15), but lower risk of SGA birth (10.2% v. 11.0%, adjusted RR 0.92, 95% CI 0.90-0.94), while infants of family-class immigrants had higher risk of SGA birth (12.2% v. 11.0%, adjusted RR 1.01, 95% CI 1.00-1.02). Risk of stillbirth, neonatal death, and overall infant death did not differ significantly among immigrant groups.

INTERPRETATION

Heterogeneity exists in outcomes of infants born to immigrants to Canada across immigration categories. These results highlight the importance of disaggregating immigrant populations in studies of health disparities.

Severe Maternal Morbidity and Mental Health Hospitalizations or Emergency Department Visits

Importance

Severe maternal morbidity (SMM) can have long-term health consequences for the affected mother. The association between SMM and future maternal mental health conditions has not been well studied.

Objective

To assess the association between SMM in the first recorded birth and the risk of hospitalization or emergency department (ED) visits for a mental health condition over a 13-year period.

Design, Setting, and Participants

This population-based retrospective cohort study used data from postpartum individuals aged 18 to 55 years with a first hospital delivery between 2008 and 2021 in 11 provinces and territories in Canada, except Québec. Data were analyzed from January to June 2023.

Exposure

SMM, defined as a composite of conditions, such as septic shock, severe preeclampsia or eclampsia, severe hemorrhage with intervention, or other complications, occurring after 20 weeks' gestation and up to 42 days after a first delivery.

Main Outcomes and Measures

The main outcome was a hospitalization or ED visit for a mental health condition, including mood and anxiety disorders, substance use, schizophrenia, and other psychotic disorder, or suicidality or self-harm event, arising at least 43 days after the first birth hospitalization. Cox regression models generated hazard ratios with 95% CIs, adjusted for baseline maternal comorbidities, maternal age at delivery, income quintile, type of residence, hospital type, and delivery year.

Results

Of 2 026 594 individuals with a first hospital delivery, 1 579 392 individuals (mean [SD] age, 30.0 [5.4] years) had complete ED and hospital records and were included in analyses; among these, 35 825 individuals (2.3%) had SMM. Compared with individuals without SMM, those with SMM were older (mean [SD] age, 29.9 [5.4] years vs 30.7 [6.0] years), were more likely to deliver in a teaching tertiary care hospital (40.8% vs 51.1%), and to have preexisting conditions (eg, ≥2 conditions: 1.2% vs 5.3%), gestational diabetes (8.2% vs 11.7%), stillbirth (0.5% vs 1.6%), preterm birth (7.7% vs 25.0%), or cesarean delivery (31.0% vs 54.3%). After a median (IQR) duration of 2.6 (1.3-6.4) years, 1287 (96.1 per 10 000) individuals with SMM had a mental health hospitalization or ED visit, compared with 41 779 (73.2 per 10 000) individuals without SMM (adjusted hazard ratio, 1.26 [95% CI, 1.19-1.34]).

Conclusions and Relevance

In this cohort study of postpartum individuals with and without SMM in pregnancy and delivery, there was an increased risk of mental health hospitalizations or ED visits up to 13 years after a delivery complicated by SMM. Enhanced surveillance and provision of postpartum mental health resources may be especially important after SMM.

Type of infertility and prevalence of congenital malformations

BACKGROUND

Children conceived with assisted reproductive technologies (ART) or after a long waiting time have a higher prevalence of congenital malformations, but few studies have examined the contribution of type of infertility.

OBJECTIVES

To quantify the association between causes of infertility and prevalence of malformations.

METHODS

We compared the prevalence at birth of all and severe malformations diagnosed up to age 2 between 6656 children born in 1996-2017 to parents who had previously been assessed for infertility a an academic fertility clinic ("exposed") and 10,382 children born in the same period to parents with no recent medical history of infertility ("reference"). We estimated prevalence ratios (PR) and prevalence differences (PD), by infertility status, type of treatment (non-ART, ART), and infertility diagnosis, in all children and among singletons.

RESULTS

Compared with children of parents with no infertility, children of parents with infertility had a higher prevalence of malformations (both definitions), particularly following ART conceptions. After accounting for treatment, ovulatory disorders were associated with a higher prevalence of both all (PR 1.49, 95% confidence interval (CI) 1.15, 1.93; PD 3.8, 95% CI 1.0, 6.6) and severe (PR 1.53, 95% CI 1.02, 2.29; PD 1.8, 95% CI -0.2, 3.7) malformations (the estimates refer to exposed children conceived without treatment). Unexplained and male factor infertility were associated with all and severe malformations, respectively. Estimates among singletons were similar. A diagnosis of ovulatory disorders was associated with all malformations also in analyses restricted to exposed children, regardless of treatment (we did not examine severe malformations, due to limited power).

CONCLUSIONS

In this study, ovulatory disorders were consistently associated with a higher prevalence of congenital malformations (including severe malformations) among live births, regardless of mode of conception.

Understanding and preferences regarding risk communication during pregnancy: a survey to facilitate provider communication with patients

BACKGROUND

Clear communication of medical risk helps to ensure proper patient understanding of healthcare options and supports informed decision-making. Communication involving visual and written risk typically conveys risk more effectively than conversations alone between a patient and a clinician. However, perception of risk is context-dependent, and the efficacy of and preferences for commonly-used risk communication formats are not well-understood during pregnancy, which is a time of complex decision-making. We sought to address this knowledge gap.

OBJECTIVE

This study aimed to assess pregnant and recently pregnant people's understanding and preferences for different risk communication formats.

STUDY DESIGN

We conducted an open online REDCap survey of pregnant and recently pregnant people over a 1-month period in 2022. Study participants were aged 16 to 49 years, pregnant or recently pregnant, and able to provide informed consent in English. Data collected included demographics, measurements of accuracy of understanding including both gist accuracy (general understanding) and verbatim accuracy (numeric quantification), and preferences for risk communication formats including icon arrays, pie charts, bar graphs, and text. Descriptive analyses of the proportion of correctly answered questions were calculated.

RESULTS

A total of 247 participants completed ≥1 item on accuracy and risk communication preferences, and 230 provided complete responses. Gist (general) understanding was accurate between 74% and 89% of the time for most graphical formats. Verbatim understanding (exact numeric quantification) was approximately 90% accurate for most formats. Respondents preferred that figures be used over circles to display risk in icon arrays, both for themselves and for infants, although figures generated more worry. However, participants substantially preferred pie charts over bar graphs (59%-70% vs 19%-25%). Respondents preferred risk to be expressed with a lower denominator of 200 rather than a higher denominator of 1000 (79% vs 13%, although the lower denominator generated more worry), and in terms of chance of survival rather than chance of death (50% vs 33%).

CONCLUSION

In a survey of pregnant and recently pregnant people, most respondents preferred pie charts over other graph formats, and lower rather than higher denominators in text. Presentations of survival rather than death estimates were also preferred. Approximately 75% to 90% of respondents accurately understood risk presented with visual and written communication. For the remaining participants, for whom accurate understanding was challenging, new strategies need to be developed.

The Impact of Burn Size on Community Participation: A Life Impact Burn Recovery Evaluation (LIBRE) Study

OBJECTIVE

To assess the association of burn size and community participation as measured by the LIBRE Profile.

SUMMARY OF BACKGROUND DATA

Burn size is an established clinical predictor of survival after burn injury. It is often a factor in guiding decisions surrounding early medical interventions; however, literature is inconclusive on its relationship to quality of life outcomes.

METHODS

This is a secondary data analysis of a cross-sectional survey of adult burn survivors. Self-reported data were collected between October 2014 and December 2015 from 601 burn survivors aged ≥18 years with ≥5% total body surface area (TBSA) or burns to critical areas. Sociodemographic characteristics were compared between participants with small burns (≤40% TBSA burned) and large burns (>40% TBSA burned). Ordinary least squares regression models examined associations between burn size and LIBRE Profile scale scores with adjustments for sex, current work status, burns to critical areas, and time since burn injury.

RESULTS

The analytic sample comprised 562 participants with data available for burn size. 42% of respondents had large burns (>40% TBSA burned) and 58% reported smaller burns (TBSA ≤40%). In adjusted regression models, patients with large burns tended to score lower on the Social Activities and Work & Employment scales ( P < 0.05) and higher on the Family & Friends scale ( P < 0.05). Participants with burns >40% TBSA scored lower for several individual items in the Social Activities scale and one item in the Work & Employment scale ( P < 0.05).

CONCLUSIONS

Increasing burn size was found to be negatively associated with selected items of Work & Employment and Social Activities, but positively associated with aspects of Family & Friend Relationships. Future longitudinal studies are necessary to assess and understand the long-term social impact of burn injuries on adult populations.

The influence of regulation of medically assisted reproduction on the risk of hospitalization in the first 2 years of life

STUDY QUESTION

Do publicly funded fertility treatment and single embryo transfer (SET) result in lower hospitalization rates of children of parents with infertility?

SUMMARY ANSWER

Following the 2010 Quebec law introducing free fertility treatment and SET, neonatal intensive care unit (NICU) admissions decreased among all children born to parents with infertility, but not among singletons, whose risk remained slightly higher than that of children of parents without infertility, even accounting for treatment and maternal age.

WHAT IS KNOWN ALREADY

Previous studies reported lower NICU admission rates among children conceived with ART after the 2010 law; however, children conceived without ART by parents with infertility were not considered.

STUDY DESIGN, SIZE, DURATION

Cohort study of children born in 1997-2017 to patients evaluated for infertility ('exposed') at an academic fertility center in Montreal (Canada) in 1996-2015. A random sample of births to Montreal residents served as comparison. Outcomes were identified from Quebec administrative databases.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We compared children's healthcare utilization before and after the 2010 law in 6273 exposed and 12 583 randomly sampled births (6846 and 12 775 children, respectively). We repeated the analysis among children conceived in the 63 months before and after the law ('restricted period'), and examined whether differences in twinning, fertility treatment, and maternal age explained the higher risk of NICU admission among children of parents with infertility.

MAIN RESULTS AND THE ROLE OF CHANCE

In the exposed cohort, the proportion of twin births and of several adverse outcomes declined after the law. NICU admission and duration of NICU stay decreased overall, but not in singletons. Both measures remained higher in exposed children. Except for NICU admission, hospitalization rates were similar in exposed and random sample children. After accounting for fertility treatment and maternal age, exposed singletons were 17% more likely to be admitted to the NICU than children of parents with no medical history of infertility.

LIMITATIONS, REASONS FOR CAUTION

Sample size was relatively small; infertile patients were from a single center and the random sample from one city. Despite some limitations, administrative databases are likely to accurately reflect healthcare utilization.

WIDER IMPLICATIONS OF THE FINDINGS

Universal access to treatment and, particularly, SET results in an overall reduction of adverse outcomes among children conceived with treatment; however, children of parents with infertility are at a slightly higher risk, regardless of treatment.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the Canadian Institutes for Health Research (CIHR, grant no. 123362). No competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Development and internal validation of a model predicting severe maternal morbidity using pre-conception and early pregnancy variables: a population-based study in Ontario, Canada

BACKGROUND

Improvement in the prediction and prevention of severe maternal morbidity (SMM) - a range of life-threatening conditions during pregnancy, at delivery or within 42 days postpartum - is a public health priority. Reduction of SMM at a population level would be facilitated by early identification and prediction. We sought to develop and internally validate a model to predict maternal end-organ injury or death using variables routinely collected during pre-pregnancy and the early pregnancy period.

METHODS

We performed a population-based cohort study using linked administrative health data in Ontario, Canada, from April 1, 2006 to March 31, 2014. We included women aged 18-60 years with a livebirth or stillbirth, of which one birth was randomly selected per woman. We constructed a clinical prediction model for the primary composite outcome of any maternal end-organ injury or death, arising between 20 weeks' gestation and 42 days after the birth hospital discharge date. Our model included variables collected from 12 months before estimated conception until 19 weeks' gestation. We developed a separate model for parous women to allow for the inclusion of factors from previous pregnancy(ies).

RESULTS

Of 634,290 women, 1969 experienced the primary composite outcome (3.1 per 1000). Predictive factors in the main model included maternal world region of origin, chronic medical conditions, parity, and obstetrical/perinatal issues - with moderate model discrimination (C-statistic 0.68, 95% CI 0.66-0.69). Among 333,435 parous women, the C-statistic was 0.71 (0.69-0.73) in the model using variables from the current (index) pregnancy as well as pre-pregnancy predictors and variables from any previous pregnancy.

CONCLUSIONS

A combination of factors ascertained early in pregnancy through a basic medical history help to identify women at risk for severe morbidity, who may benefit from targeted preventive and surveillance strategies including appropriate specialty-based antenatal care pathways. Further refinement and external validation of this model are warranted and can support evidence-based improvements in clinical practice.

Housing conditions and adverse birth outcomes among Indigenous people in Canada

Objectives

Poor housing conditions and household crowding have been identified as important health concerns for Indigenous populations in many countries but have not been explored in relation to adverse birth outcomes in these populations. We investigated housing conditions and adverse birth outcomes in a nationally representative sample of Indigenous people in Canada.

Methods

Data were from a cohort of births between May 2004 and May 2006 created by linking birth and infant death registration data with the 2006 Canadian census. Log-binomial regression was used to examine associations between housing variables (persons per room and needed household repairs) and three adverse birth outcomes: preterm birth (PTB), small-for-gestational-age (SGA) birth, and infant mortality. Separate regression models were run for First Nations, Métis and Inuit mothers, with adjustment for parity and parental socio-economic variables.

Results

Need for major household repairs was associated with a slightly increased risk of PTB among First Nations and Métis mothers (adjusted RRs 1.12 and 1.13, respectively; 95% CI 0.94–1.34 and 0.89–1.44, respectively) and a moderately increased risk of infant death in all three groups (aRR = 1.69, 95% CI 1.00–2.85). Household crowding was also associated with a slightly elevated risk of PTB in all three groups (aRR = 1.10, 95% CI 0.95–1.29) and with an increased risk of infant mortality among First Nations (aRR = 1.57, 95% CI 0.97–2.53).

Conclusion

This study highlights the need to improve understanding of links between housing conditions and perinatal health outcomes in Indigenous populations, including examining cause-specific infant mortality in relation to housing characteristics.

Supplementary Information

The online version contains supplementary material available at 10.17269/s41997-021-00527-2.

Postpartum Analgesia in New Mothers (PAIN) Study: A Survey of Canadian Obstetricians' Post-Delivery Opioid-Prescribing Practices

OBJECTIVE

We aimed to describe opioid prescribing practices after obstetric delivery and to evaluate how these practices compare with national opioid prescribing guidelines.

METHODS

A closed survey was developed, evaluated for validity and reliability, and distributed by email to obstetrician members of the Society of Obstetricians and Gynaecologists of Canada (SOGC) in December 2018. Descriptive statistics were used to summarize respondent demographics, pharmaceutical pain management strategies, and opioid prescribing practices. Logistic regression was used to measure associations between respondent characteristics and high-risk opioid prescribing practices (e.g., prescribing >50 mg morphine equivalent dose per day, prescribing >5 days, not screening for substance/opioid use disorder before prescribing).

RESULTS

Our survey had high content validity (content validity index 0.89; 95% CI 0.78-1.00) and adequate reliability (Kappa 0.70; 95% CI 0.63-0.84 and intraclass correlation coefficient 0.70; 95% CI 0.67-0.81). Of the 1019 SOGC members reached, 243 initiated the survey (response rate, 24%). Among respondents, 235 (92%) completed the survey. Among opioid prescribers, 47% reported at least 1 high-risk opioid prescribing practice, the most frequent being a lack of substance/opioid use disorder screening. In the adjusted logistic regression model, being in practice more than 20 years (adjusted odds ratio [aOR] 0.53; 95% CI 0.29-0.93) and practising in a non-central area of Canada (aOR 0.49; 95% CI 0.28-0.84) reduced the odds of high-risk prescribing.

CONCLUSION

Further research on barriers to screening are needed to support and enhance safer opioid prescribing practices among Canadian obstetricians.

Sexual activity and romantic relationships after burn injury: A Life Impact Burn Recovery Evaluation (LIBRE) study

BACKGROUND

Engaging in healthy sexual activity and romantic relationships are important but often neglected areas of post-burn rehabilitation. The degree to which persons with burn injuries engage in sexual activity and romantic relationships is not well understood. This study examined demographic and clinical characteristics predicting engagement in sexual activity and romantic relationships in a sample of adult burn survivors compared to a general United States sample.

METHODS

Data for the adult burn survivor sample were from 601 adult burn survivors who participated in field-testing for the calibration of the Life Impact Burn Recovery Evaluation (LIBRE) Profile, a burn-specific instrument assessing social participation on six scales including sexual activity and romantic relationships. Comparison data were obtained from a general population sample of 2000 adults through sample matching. Demographic predictors of sexual activity and romantic relationship status were examined in each sample using modified Poisson regression analyses. Clinical predictors of engaging in sexual activity and romantic relationships were also examined in the LIBRE sample.

RESULTS

Participants were slightly more likely to report being sexually active in the adult burn survivor sample than in the general sample (65% vs. 57%, p < 0.01). There was not a significant difference in romantic relationship status between the two samples (64% vs. 62%, p = 0.31). In multivariable regression analyses, men in both samples were more likely to report being in a sexual relationship (RR in LIBRE sample = 1.23, 95% CI 1.08-1.39; RR in general sample = 1.10, 95% CI 1.02-1.18). Participants in both samples who were not working were less likely to report being sexually active or in a romantic relationship (RRs ranging from 0.73 to 0.83, p < 0.05 for all estimates). In the adult burn survivor sample, respondents with hand burns were more likely to report being sexually active and in a romantic relationship (RR = 1.16, 95% CI 1.01-1.33). Time since burn injury, burn size, and burns to other critical areas were not significantly associated with either outcome in adjusted analyses.

CONCLUSIONS

The likelihood of engaging in sexual activity and romantic relationships is similar among adult burn survivors and the comparison group representing a general United States sample of adults. Further research addressing sexual activity and romantic relationships after burn injuries will help to foster better patient-clinician dialogue, pinpoint barriers, design interventions, and allocate appropriate resources.

Translation and Cross-cultural Validation of the English Young Adult Burn Outcome Questionnaire (YABOQ) in Spanish

The Young Adult Burn Outcome Questionnaire (YABOQ) is a validated, English-language patient-reported outcome assessment of young adults' recovery from burn injury across 15 scale domains. We evaluated the cross-cultural validity of a newly developed Spanish version of the YABOQ. Secondary data from English- and Spanish-speaking burn survivors (17 to 30 years of age) were obtained from the Multicenter Benchmarking Study. We conducted classic psychometric analyses and evaluated the measurement equivalence of the English and Spanish YABOQs in logistic and ordinal logistic regression differential item functioning analyses. All multi-item scales in the Spanish YABOQ demonstrated adequate reliability except the Pain and Itch scales. One item in the Perceived Appearance scale showed differential item functioning across English- and Spanish-speaking burn survivors, but the observed differential item functioning had no clinically significant impact on scale-level Perceived Appearance scores. Our findings support the cross-cultural validity of the YABOQ Physical Function, Perceived Appearance, Sexual Function, Emotion, Family Function, Family Concern, Satisfaction with Symptom Relief, Satisfaction with Role, Work Reintegration and Religion scales among English- and Spanish-speaking young adult burn survivors. This work supports the use of these English and Spanish YABOQ scales to assess the effect of therapeutic interventions on young adults' burn outcomes in pooled analyses and to assess disparities in young adults' burn outcomes across language groups.

Social Interactions and Social Activities After Burn Injury: A Life Impact Burn Recovery Evaluation (LIBRE) Study

Social interactions and activities are key components of social recovery following burn injuries. The objective of this study is to determine the predictors of these areas of social recovery. This study provides a secondary analysis of a cross-sectional survey of adult burn survivors. The Life Impact Burn Recovery Evaluation-192 was administered to 601 burn survivors for the field-testing of the Life Impact Burn Recovery Evaluation Profile. Survivors aged 18 years and older with injuries ≥5% total BSA or burns to critical areas (hands, feet, face, or genitals) were eligible to participate. Multivariate linear regression analyses were used to determine predictors of the Social Activities and Social Interactions scale scores. A total of 599 people completed the Social Interactions and Social Activities scales. Of these, 77% identified as White Non-Hispanic, 55% were female, 55% were unmarried, and 80% had burns to critical areas. Participants had a mean age of 45 years, a mean time since burn injury of 15 years, and a mean burn size of 41% total BSA. Younger age (P < .01) and being married/living with a significant other (P ≤ .01) were associated with higher Social Activities and Social Interactions scale scores. Individual item responses reveal that survivors had lower scores on items related to participating in outdoor activities (30.4%) or feeling uncomfortable with their appearance (32.4% report dressing to avoid stares). Social interactions and activities are long-term challenges for burn survivors. It is important for clinicians to identify patients who may struggle with social recovery in order to focus on future community-based interventions.

The Effect of Facial Burns on Long-Term Outcomes in Young Adults: A 5-Year Study

Long-term functional outcomes in young adults with facial burns remain poorly studied. This 5-year (2003-2008) prospective multicenter study includes burn survivors (age 19-30 years) who completed the Young Adult Burn Outcome Questionnaire (YABOQ) from 0 to 36 months after baseline survey administration. A composite canonical score was developed from 15 YABOQ domains using discriminant analysis, maximizing the difference at the baseline between burn-injured patients with face involved and not involved. A generalized linear model with the generalized estimation equation technique was used to track the changing pattern of the composite score over time. Individual domain scores with high correlation to the canonical score were used to evaluate recovery patterns in facial burns. A total of 153 burned (31% with face burns) and 112 nonburned subjects completed 620 questionnaires. Canonical analysis showed that early postburn, facial burns were associated with a difference in outcome, but this overall difference diminished over time. Regression analysis showed that for survivors with facial injury, Emotion and Sexual Function scores were persistently lower (worse), while Religion scores were persistently higher. Satisfaction with Role was initially better than the nonface burned group, but over time got worse, while Perceived Appearance was initially worse in the face burned group but this difference diminished over time. Social Function Limited by Appearance was initially similar between the groups, but over time the group with face burns scored lower. The overall difference in recovery between survivors with and without facial burns diminished over time while the individual domains had various patterns of recovery.

The Relationship of Level of Education to Social Reintegration after Burn Injury: A LIBRE Study

Social and emotional recovery from burn injury is a complex process impacted by both clinical and social factors. Because level of education (LOE) has been correlated to overall health, health outcomes, and life expectancy, we questioned whether LOE might be associated with successful social recovery after burn injury. The Life Impact Burn Recovery Evaluation (LIBRE) data set served as a novel tool to explore this question. The LIBRE project is a collaborative effort designed to provide a clinical yardstick for social reintegration among burn survivors. After institutional review board approval, 601 burn survivor respondents, aged 18 or over with >5% TBSA burn were surveyed and a six-scale, 126-item LIBRE Profile was derived from their responses. LOE was collapsed into four categories ranging from less than high school equivalency certificate to graduate degree. Impact of burn injury on subsequent LOE was examined by splitting the sample into those burned at age 30 years or less and those burned at greater than 30 years of age. Regression models were run to estimate associations between education and scale scores with adjustment for age at injury, sex, marital status, work status, TBSA, and time since burn. Regression models were run on the entire cohort and then stratified by age at burn injury (≤30 vs >30). Among all subjects, we found an association between LOE and social recovery as measured by LIBRE scale scores. This association was contributed entirely from the cohort burned at age 30 or less: for those burned at greater than age 30, there was no association between LOE and social recovery. Of particular interest, the distribution of LOE among those burned at ≤ 30 was very similar to LOE distribution in both millennials and in the U.S. population at large. LOE appears to be associated with social recovery for those burned at younger ages but not for those burned at over age 30. More importantly, burn injury during schooling may have no impact on a survivor's educational trajectory since distribution of LOE in our ≤30 cohort mirrors that of the general population. LOE and age at burn injury may provide a quick screen for survivors at risk of difficult social reintegration, allowing providers to target those at risk with additional peer support and counseling.

Association between maternal urinary speciated arsenic concentrations and gestational diabetes in a cohort of Canadian women

BACKGROUND

Epidemiological and toxicological evidence suggests that maternal total arsenic (As) levels are associated with an elevated risk of gestational diabetes (GDM). Uncertainty remains regarding the metabolic toxicity of specific arsenic species, comprised of both organic and inorganic sources of arsenic exposure.

OBJECTIVES

We assessed associations between speciated As and GDM using data from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study.

METHODS

Concentrations of speciated As [(inorganic (trivalent, pentavalent)), methylated arsenic species metabolites (monomethylarsonic acid (MMA), dimethylarsinic acid (DMA)), and organic (arsenobetaine)] were measured in first trimester maternal urine samples. GDM cases were identified in accordance with Canadian guidelines. Multivariable regression models were used to estimate associations between speciated As and GDM, evaluate potential interaction between speciated As exposures, and assess fetal sex-specific findings.

RESULTS

Among 1243 women who had a live, singleton birth and no previous history of diabetes, 4% met the diagnostic criteria for GDM. Our analyses focused on DMA and arsenobetaine as these were the subtypes with detectable concentrations in at least 40% of samples. Compared to women in the lowest tertile of DMA (<1.49 μg As/L), women with concentrations exceeding 3.52 μg As/L (3rd tertile) experienced an increased risk of GDM (aOR = 3.86; 95% CI: 1.18, 12.57) (p-value for trend across tertiles = 0.04). When restricted to women carrying male infants, the magnitude of this association increased (aOR 3rd tertile = 4.71; 95% CI: 1.05, 21.10).

CONCLUSIONS

These results suggest a positive relation between DMA and GDM; potential differences in risk by fetal sex requires further investigation.

The Associations of Gender With Social Participation of Burn Survivors: A Life Impact Burn Recovery Evaluation Profile Study

Burn injury can be debilitating and affect survivors' quality of life in a profound fashion. Burn injury may also lead to serious psychosocial challenges that have not been adequately studied and addressed. Specifically, there has been limited research into the associations of burn injury on community reintegration based on gender. This work analyzed data from 601 burn survivors who completed field testing of a new measure of social participation for burn survivors, the Life Impact Burn Recovery Evaluation (LIBRE) Profile. Differences in item responses between men and women were examined. Scores on the six LIBRE Profile scales were then compared between men and women using analysis of variance and adjusted linear multivariate regression modeling. Overall, men scored significantly better than women on four of the six LIBRE Profile scales: Sexual Relationships, Social Interactions, Work & Employment, and Romantic Relationships. Differences were not substantially reduced after adjustment for demographic characteristics and burn size. Men scored better than women in most of the areas measured by the LIBRE Profile. These gender differences are potentially important for managing burn patients during the post-injury recovery period.

Adverse birth outcomes and infant mortality according to registered First Nations status and First Nations community residence across Canada

OBJECTIVE

Studies of perinatal health outcomes in Canadian First Nations populations have largely focused on limited geographical areas and have been unable to examine outcomes by registered status and community residence. In this study, we compare rates of adverse birth outcomes among First Nations individuals living within vs. outside of First Nations communities and those with vs. without registered status.

METHODS

Data included 13,506 singleton pregnancies from the 2006 Canadian Birth-Census Cohort. Outcomes examined included preterm birth (PTB), small- and large-for-gestational-age birth (SGA, LGA), stillbirth, overall infant mortality, and neonatal and postneonatal mortality. Risk ratios (RRs) were estimated with adjustment for maternal age, education, parity, and paternal education.

RESULTS

Mothers living in First Nations communities and those with status had elevated adjusted risks of LGA (RR for First Nations community residence = 1.22, 95% CI = 1.09-1.35; RR for status = 1.50, 95% CI = 1.16-1.93). Rates of SGA were significantly lower among mothers with status (adjusted RR = 0.62, 95% CI = 0.44-0.86). Rates of PTB did not vary substantially by residence or by status. Adjusted differences in fatal outcomes could not be estimated, owing to small cell sizes. However, mothers living in First Nations communities had higher crude rates of infant mortality (10.9 vs. 7.7 per 1000), particularly for neonatal mortality (6.1 vs. 2.9).

CONCLUSION

Future investigations should explore risk factors, including food security and access to health care services, that may explain disparities in SGA and LGA by status and residence within First Nations populations.

The Development and Validity of the Adult Burn Outcome Questionnaire Short Form

Patient Reported Outcome Measures (PROMs) are useful for understanding the health needs and outcomes of the general public. We aim to develop a burn-specific metric-Adult Burn Outcome Questionnaire (ABOQ)-that is brief and can be administered electronically to all burn survivors over the age of 18. The 14-item ABOQ was developed from the already validated Young Adult Burn Outcome Questionnaire (YABOQ) long form. The ABOQ questionnaire, along with Patient-Reported Outcomes Measurement System-10 (PROMIS-10), was administered to 120 outpatient burn survivors at three hospitals. Clinical validity of the ABOQ was measured by testing associations between ABOQ items and burn size, the PROMIS-10 generic items and composite scales using correlational analysis including multivariate canonical analysis. Nine out of 14 ABOQ items were significantly correlated with burn size (correlations ranging from -0.25 to -0.46, P < .01). The canonical correlation between ABOQ and burn size was 0.68 (P = .0002). The overall canonical correlation between two instruments was also significant (P < .0001). At the item level, at least 25% of the variation in each of the five ABOQ items could be explained by PROMIS-10 items and composite scores, while six other items could only be accounted for by less than 15% of the variation. ABOQ short form assessment can be used to efficiently measure burn outcomes across a range of relevant clinical domains with credible validity. A large proportion of the variation in ABOQ scores was not accounted for by PROMIS-10, suggesting that ABOQ provided additional health-related information specifically for the burn population beyond the generic instrument.

The Predictive Value of Head Circumference Growth during the First Year of Life on Early Child Traits

Atypical head circumference (HC) growth has been associated with neurodevelopmental disorders. However, whether it is associated with specific aspects of development in early childhood in the general population is unknown. The objective of this study was to assess the predictive value of HC growth as an early biomarker of behavioral traits. We examined longitudinal associations between HC growth from 0 to 12 months and temperament, cognitive, and motor development at 24 months. A subsample of healthy children (N = 756) was drawn from the 3D (Design, Develop, Discover) cohort study. Early HC growth was modeled with latent growth curve analysis. Greater postnatal HC growth predicted lower temperamental effortful control and lower surgency/extraversion in boys. HC growth did not predict cognitive or fine motor scores, but did predict greater gross motor skills in boys. No significant effect of HC growth was found in girls. This study is the first to demonstrate an association between postnatal HC growth and specific aspects of child development in a healthy population. Results suggest HC growth overshadows brain mechanisms involved in behavioral traits in early infancy. Whether links are maintained throughout development and the mechanisms involved correspond to traits found in atypical populations remains to be studied.

Maternal and cord blood manganese (Mn) levels and birth weight: The MIREC birth cohort study

Epidemiological studies have hypothesized that both insufficient and excess blood manganese (Mn) levels during pregnancy are associated with reduced fetal growth. This literature is characterized by inconsistent results and a limited focus on women with exposures representative of the general North American population. We examined the relationship between maternal and cord blood Mn levels and fetal growth among women enrolled in the Maternal-Infant Research on Environmental Chemicals Study (MIREC). Mothers with singleton, term infants and complete maternal first and third trimester blood Mn data were eligible for inclusion in the present study (n = 1519). Mean birth weight and odds ratios of small for gestational age (SGA) births according to maternal and cord blood Mn levels (low (<10), referent (10-<90), high (≥90) percentiles) were estimated. We also evaluated the association between the ratio of cord and maternal blood Mn and birth weight. Women with low (<0.82 μg/dL) maternal blood third trimester Mn levels had infants that weighed an average of 64.7 g (95% CI: -142.3,12.8) less than infants born to women in the referent exposure group. This association was strengthened and became statistically significant when adjusted for toxic metals (lead, mercury, arsenic, and cadmium) [-83.3 g (95% CI: -162.4, -4.1)]. No statistically significant associations were observed in models of maternal first trimester or cord blood Mn. A one unit increase in the cord/maternal blood Mn ratio was associated with a 29.4 g (95% CI: -50.2, -8.7), when adjusted for maternal and neonatal characteristics. Our findings motivate additional research regarding the relation between Mn exposure and fetal growth. Further inquiry is necessary to determine whether an exposure threshold exists, how growth related effects of maternal and fetal Mn may differ, and how concurrent exposure to other toxic metals may impact the association between Mn and growth.

Adverse birth outcomes in relation to maternal marital and cohabitation status in Canada

PURPOSE

An increasing percentage of children are born to couples who cohabit but are not legally married. Using data from a nationally representative Canadian sample, we estimated associations of maternal marital and cohabitation status with stillbirth, infant mortality, preterm birth (PTB), and small- and large-for-gestational-age (SGA and LGA) birth.

METHODS

The 2006 Canadian Birth-Census Cohort was created by linking birth registration data with the 2006 long-form census. We used log-binomial regression to estimate risk ratios (RRs) for adverse birth outcomes associated with being single or living with a common-law partner. Analyses were adjusted for maternal age and education.

RESULTS

Data were analyzed for 130,931 singleton births. Adjusted RRs (95% confidence intervals) for single mothers compared with married mothers were 1.92 (1.51-2.42) for stillbirth, 2.08 (1.55-2.81) for infant mortality, 1.36 (1.27-1.46) for PTB, 1.31 (1.22-1.39) for SGA birth, and 0.95 (0.90-1.01) for LGA birth. Adjusted RRs for cohabiting mothers compared with married mothers were 0.93 (0.74-1.16) for stillbirth, 1.05 (0.81-1.35) for infant mortality, 1.09 (1.03-1.15) for PTB, 1.05 (0.99-1.10) for SGA birth, and 0.96 (0.92-1.00) for LGA birth.

CONCLUSIONS

In a nationally representative Canadian birth cohort, cohabiting and legally married women experienced similar birth outcomes, but most outcomes for single women were substantially worse.

Associations between maternal triclosan concentrations in early pregnancy and gestational diabetes mellitus, impaired glucose tolerance, gestational weight gain and fetal markers of metabolic function

BACKGROUND

Triclosan is a phenolic biocide used in a multitude of consumer products and in health care settings. It is widely detected in the American and Canadian populations and has been shown in animal models to act as an endocrine disrupting agent. However, there has been little examination to date of the effects of triclosan exposure in pregnancy on perinatal metabolic outcomes in human populations.

METHODS

Using data from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, a Canadian pregnancy cohort, we measured associations of first-trimester urinary triclosan concentrations with total gestational weight gain, gestational diabetes mellitus and impaired glucose tolerance in pregnancy, and fetal markers of metabolic function. Leptin and adiponectin were measured in plasma from umbilical cord blood samples in term neonates and categorized into low (< 10th percentile), intermediate (10th-90th percentile) and high (> 90th percentile) levels. Triclosan concentrations were grouped into quartiles and associations with study outcomes were examined using logistic regression models with adjustment for maternal age, race/ethnicity, pre-pregnancy BMI, education and urinary specific gravity. Restricted cubic spline analysis was performed to help assess linearity and shape of any dose-response relationships. All analyses for leptin and adiponectin levels were performed on the entire cohort as well as stratified by fetal sex.

RESULTS

Triclosan measures were available for 1795 MIREC participants with a live born singleton birth. Regression analyses showed a non-significant inverse association between triclosan concentrations and leptin levels above the 90th percentile that was restricted to female fetuses (OR for highest quartile of triclosan compared to lowest quartile = 0.4 (95% CI 0.2-1.1), p-value for trend across quartiles = 0.02). Triclosan concentrations in the second quartile were associated with elevated odds of adiponectin below the 10th percentile in male fetuses (OR for Q2 compared to Q1 = 2.5, 95% CI 1.1-5.9, p-value for trend across quartiles = 0.93). No significant linear associations between triclosan concentrations and leptin or adiponectin levels in overall or sex-specific analyses were observed from restricted cubic spline analyses. No significant associations were observed in adjusted analyses between triclosan concentrations and gestational diabetes mellitus, impaired glucose tolerance or gestational weight gain.

CONCLUSIONS

This study does not support an association between triclosan concentrations in pregnancy and fetal metabolic markers, glucose disorders of pregnancy, or excessive gestational weight gain.

Impact of Work-Related Burn Injury on Social Reintegration Outcomes: A Life Impact Burn Recovery Evaluation (LIBRE) Study

OBJECTIVE

To examine differences in long-term social reintegration outcomes for burn survivors with and without work-related injuries.

DESIGN

Cross-sectional survey.

SETTING

Community-dwelling burn survivors.

PARTICIPANTS

Burn survivors (N=601) aged ≥18 years with injuries to ≥5% total body surface area or burns to critical areas (hands, feet, face, or genitals).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The Life Impact Burn Recovery Evaluation Profile was used to examine the following previously validated 6 scale scores of social participation: Family and Friends, Social Interactions, Social Activities, Work and Employment, Romantic Relationships, and Sexual Relationships.

RESULTS

Older participants, those who were married, and men were more likely to be burned at work (P<.01). Burn survivors who were injured at work scored significantly lower on the Work and Employment scale score after adjusting for demographic and clinical characteristics (P=.01). All other domain scale scores demonstrated no significant differences between groups. Individuals with work-related injuries scored significantly worse on 6 of the 19 items within the Work and Employment scale (P<.05). These individuals were more likely to report that they were afraid to go to work and felt limited in their ability to perform at work.

CONCLUSIONS

Burn survivors with work-related injuries report worse work reintegration outcomes than those without work-related injuries. Identification of those at higher risk for work reintegration challenges after burn injury may enable survivors, providers, employers, and insurers to better use appropriate resources to promote and target optimal employment outcomes.

Birth outcomes among First Nations, Inuit and Métis populations

BACKGROUND

First Nations, Inuit, and Métis are at higher risk of adverse birth outcomes than are non-Indigenous people. However, relatively little perinatal information is available at the national level for Indigenous people overall or for specific identity groups.

DATA AND METHODS

This analysis describes and compares rates of preterm birth, small-for-gestational-age birth, large-for-gestational-age birth, stillbirth, and infant mortality (neonatal, postneonatal, and cause-specific) in a nationally representative sample of First Nations, Inuit, Métis, and non-Indigenous births. The study cohort consisted of 17,547 births to Indigenous mothers and 112,112 births to non-Indigenous mothers from 2004 through 2006. The cohort was created by linking the Canadian Live Birth, Infant Death and Stillbirth Database to the long form of the 2006 Census, which contains a self-reported Indigenous identifier.

RESULTS

With the exception of small-for-gestational-age birth, adverse birth outcomes occurred more frequently among First Nations, Inuit, and Métis women than among non-Indigenous women. Inuit had the highest preterm birth rate (11.4 per 100 births; 95% CI: 9.7 to 13.1) among the three Indigenous groups. The large-for-gestational-age rate was highest for First Nations births (20.9 per 100 births; 95% CI: 19.9 to 21.8). Infant mortality rates were more than twice as high for each Indigenous group compared with the non-Indigenous population, and rates of sudden infant death syndrome were more than seven times higher among First Nations and Inuit.

DISCUSSION

The results confirm disparities in birth outcomes between Indigenous and non-Indigenous populations, and demonstrate differences among First Nations, Métis and Inuit.

Long-Term Social Reintegration Outcomes for Burn Survivors With and Without Peer Support Attendance: A Life Impact Burn Recovery Evaluation (LIBRE) Study

OBJECTIVE

To examine differences in long-term social reintegration outcomes for burn survivors with and without peer support attendance.

DESIGN

Cross-sectional survey.

SETTING

Community-dwelling burn survivors.

PARTICIPANTS

Burn survivors (N=601) aged ≥18 years with injuries to ≥5% total body surface area (TBSA) or burns to critical areas (hands, feet, face, or genitals).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The Life Impact Burn Recovery Evaluation Profile was used to examine the following previously validated 6 scale scores of social participation: Family and Friends, Social Interactions, Social Activities, Work and Employment, Romantic Relationships, and Sexual Relationships.

RESULTS

Burn support group attendance was reported by 330 (55%) of 596 respondents who responded to this item. Attendees had larger burn size (43.4%±23.6% vs 36.8%±23.4% TBSA burned, P<.01) and were more likely to be >10 years from injury (50% vs 42.5%, P<.01). Survivors who attended at least 1 support group scored significantly higher on 3 of the scales: Social Interactions (P=.01), Social Activities (P=.04), and Work and Employment (P=.05). In adjusted analyses, peer support attendance was associated with increased scores on the Social Interactions scale, increasing scores by 17% of an SD (95% confidence interval, 1%-33%; P=.04).

CONCLUSIONS

Burn survivors who reported peer support attendance had better social interaction scores than those who did not. This is the first reported association between peer support group attendance and improvements in community reintegration in burn survivors. This cross-sectional study prompts further exploration into the potential benefits of peer support groups on burn recovery with future intervention studies.

Previous pregnancy outcomes and subsequent pregnancy anxiety in a Quebec prospective cohort

INTRODUCTION

Pregnancy anxiety is an important psychosocial risk factor that may be more strongly associated with adverse birth outcomes than other measures of stress. Better understanding of the upstream predictors and causes of pregnancy anxiety could help to identify high-risk women for adverse maternal and infant outcomes. The objective of the present study was to measure the associations between five past pregnancy outcomes (live preterm birth (PTB), live term birth, miscarriage at <20 weeks, stillbirth at ≥20 weeks, and elective abortion) and pregnancy anxiety at three trimesters in a subsequent pregnancy.

METHODS

Analyses were conducted using data from the 3D Cohort Study, a Canadian birth cohort. Data on maternal demographic characteristics and pregnancy history for each known previous pregnancy were collected via interviewer-administered questionnaires at study entry. Pregnancy anxiety for the index study pregnancy was measured prospectively by self-administered questionnaire following three prenatal study visits.

RESULTS

Of 2366 participants in the 3D Study, 1505 had at least one previous pregnancy. In linear regression analyses with adjustment for confounding variables, prior live term birth was associated with lower pregnancy anxiety in all three trimesters, whereas prior miscarriage was significantly associated with higher pregnancy anxiety in the first trimester. Prior stillbirth was associated with greater pregnancy anxiety in the third trimester. Prior elective abortion was significantly associated with higher pregnancy anxiety scores in the first and second trimesters, with an association of similar magnitude observed in the third trimester.

DISCUSSION

Our findings suggest that the outcomes of previous pregnancies should be incorporated, along with demographic and psychosocial characteristics, into conceptual models framing pregnancy anxiety.

Maternal Concentrations of Perfluoroalkyl Substances and Fetal Markers of Metabolic Function and Birth Weight

Perfluoroalkyl substances (PFAS) are ubiquitous, persistent chemicals that have been widely used in the production of common household and consumer goods for their nonflammable, lipophobic, and hydrophobic properties. Inverse associations between maternal or umbilical cord blood concentrations of perfluorooctanoic acid and perfluorooctanesulfonate and birth weight have been identified. This literature has primarily examined each PFAS individually without consideration of the potential influence of correlated exposures. Further, the association between PFAS exposures and indicators of metabolic function (i.e., leptin and adiponectin) has received limited attention. We examined associations between first-trimester maternal plasma PFAS concentrations and birth weight and cord blood concentrations of leptin and adiponectin using data on 1,705 mother-infant pairs from the Maternal Infant Research on Environmental Chemicals (MIREC) Study, a trans-Canada birth cohort study that recruited women between 2008 and 2011. Bayesian hierarchical models were used to quantify associations and calculate credible intervals. Maternal perfluorooctanoic acid concentrations were inversely associated with birth weight z score, though the null value was included in all credible intervals (log₁₀ β = −0.10, 95% credible interval: −0.34, 0.13). All associations between maternal PFAS concentrations and cord blood adipocytokine concentrations were of small magnitude and centered around the null value. Follow-up in a cohort of children is required to determine how the observed associations manifest in childhood.

Missing paternal data and adverse birth outcomes in Canada

BACKGROUND

Research on predictors of birth outcomes tends to focus on maternal characteristics. Less is known about the role of paternal factors. Missing paternal data on administrative records may be a marker for risk of adverse birth outcomes.

DATA AND METHODS

Analyses were performed on a cohort of births that occurred from May 16, 2004 through May 15, 2006, which was created by linking birth and death registration data with the 2006 Canadian census. Log-binomial and binomial regression were used to estimate relative risks and risk differences for preterm birth, small-for-gestational-age birth, stillbirth and infant mortality associated with the absence of paternal information. Analyses controlled for maternal age, education, household income, parity, marital status, ethnicity and birthplace.

RESULTS

The analyses pertained to 135,285 singleton births. Paternal data were missing from the birth registration for 7,461 births (4.6%) and from the census data for 17,713 births (11.4%). The adjusted relative risks associated with missing paternal data on the birth registration were 1.12 (95% CI: 0.99, 1.26) for preterm birth; 1.15 (1.05, 1.26) for small-for-gestational-age birth; 1.86 (1.27, 2.73) for stillbirth; and 1.53 (1.00, 2.34) for infant mortality. Estimates were robust to varying definitions of missing paternal information, based on the birth registration, census data, or both.

INTERPRETATION

This study suggests that missing paternal data is a marker for increased risk of adverse birth outcomes, over and above maternal characteristics.

3D Cohort Study: The Integrated Research Network in Perinatology of Quebec and Eastern Ontario

BACKGROUND

The 3D Cohort Study (Design, Develop, Discover) was established to help bridge knowledge gaps about the links between various adverse exposures during pregnancy with birth outcomes and later health outcomes in children.

METHODS

Pregnant women and their partners were recruited during the first trimester from nine sites in Quebec and followed along with their children through to 2 years of age. Questionnaires were administered during pregnancy and post-delivery to collect information on demographics, mental health and life style, medical history, psychosocial measures, diet, infant growth, and neurodevelopment. Information on the delivery and newborn outcomes were abstracted from medical charts. Biological specimens were collected from mothers during each trimester, fathers (once during the pregnancy), and infants (at delivery and 2 years of age) for storage in a biological specimen bank.

RESULTS

Of the 9864 women screened, 6348 met the eligibility criteria and 2366 women participated in the study (37% of eligible women). Among women in the 3D cohort, 1721 of their partners (1704 biological fathers) agreed to participate (73%). Two thousand two hundred and nineteen participants had a live singleton birth (94%). Prenatal blood and urine samples as well as vaginal secretions were collected for ≥98% of participants, cord blood for 81% of livebirths, and placental tissue for 89% of livebirths.

CONCLUSIONS

The 3D Cohort Study combines a rich bank of multiple biological specimens with extensive clinical, life style, and psychosocial data. This data set is a valuable resource for studying the developmental etiology of birth and early childhood neurodevelopmental outcomes.

Exposure to organophosphorus and organochlorine pesticides, perfluoroalkyl substances, and polychlorinated biphenyls in pregnancy and the association with impaired glucose tolerance and gestational diabetes mellitus: The MIREC Study

BACKGROUND

Studies report increases in rates of gestational diabetes mellitus (GDM) over recent decades. Environmental chemicals may increase the risk of diabetes through impacts on glucose metabolism, mitochondrial dysfunction, and endocrine-disrupting mechanisms including effects on pancreatic β-cell function and adiponectin release.

OBJECTIVES

To determine the associations between pesticides, perfluoroalkyl substances (PFASs) and polychlorinated biphenyls (PCBs) measured in early pregnancy and impaired glucose tolerance (IGT) and GDM in a Canadian birth cohort.

METHODS

Women enrolled in the Maternal-Infant Research on Environmental Chemicals (MIREC) Study were included if they had a singleton delivery and did not have pre-existing diabetes. Exposure variables included three organophosphorus (OP) pesticide metabolites detected in first-trimester urine samples, as well as three organochlorine (OC) pesticides, three PFASs, and four PCBs in first-trimester blood samples. Gestational IGT and GDM were assessed by chart review in accordance with published guidelines. Adjusted logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CI) for the association between quartiles of environmental chemicals and both gestational IGT and GDM.

RESULTS

Of the 2001 women recruited into the MIREC cohort, 1274 met the inclusion criteria and had outcome and biomonitoring data available. Significantly lower odds of GDM were observed in the third and fourth quartiles of dimethylphosphate (DMP) and in the fourth quartile of dimethylthiophosphate (DMTP) in adjusted analyses (DMP Q3: OR=0.2, 95% CI=0.1-0.7; DMP Q4: OR=0.3, 95% CI=0.1-0.8; DMTP: OR=0.3, 95% CI=0.1-0.9). Significantly elevated odds of gestational IGT was observed in the second quartile of perfluorohexane sulfonate (PFHxS) (OR=3.5, 95% CI=1.4-8.9). No evidence of associations with GDM or IGT during pregnancy was observed for PCBs or OC pesticides.

CONCLUSIONS

We did not find consistent evidence for any positive associations between the chemicals we examined and GDM or IGT during pregnancy. We observed statistical evidence of inverse relationships between urine concentrations of DMP and DMTP with GDM. We cannot rule out the influence of residual confounding due to unmeasured protective factors, such as nutritional benefits from fruit and vegetable consumption, also associated with pesticide exposure, on the observed inverse associations between maternal OP pesticide metabolites and GDM. These findings require further investigation.

Air Pollution Exposure During Pregnancy and Fetal Markers of Metabolic function: The MIREC Study

Previous evidence suggests that exposure to outdoor air pollution during pregnancy could alter fetal metabolic function, which could increase the risk of obesity in childhood. However, to our knowledge, no epidemiologic study has investigated the association between prenatal exposure to air pollution and indicators of fetal metabolic function. We investigated the association between maternal exposure to nitrogen dioxide and fine particulate matter (aerodynamic diameter ≤2.5 µm) and umbilical cord blood leptin and adiponectin levels with mixed-effects linear regression models among 1,257 mother-infant pairs from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, conducted in Canada (2008-2011). We observed that an interquartile-range increase in average exposure to fine particulate matter (3.2 µg/m(3)) during pregnancy was associated with an 11% (95% confidence interval: 4, 17) increase in adiponectin levels. We also observed 13% (95% confidence interval: 6, 20) higher adiponectin levels per interquartile-range increase in average exposure to nitrogen dioxide (13.6 parts per billion) during pregnancy. Significant associations were seen between air pollution markers and cord blood leptin levels in models that adjusted for birth weight z score but not in models that did not adjust for birth weight z score. The roles of prenatal exposure to air pollution and fetal metabolic function in the potential development of childhood obesity should be further explored.

Rankings of iron, vitamin D, and calcium intakes in relation to maternal characteristics of pregnant Canadian women

Iron, vitamin D, and calcium intakes in the prenatal period are important determinants of maternal and fetal health. The objective of this study was to examine iron, vitamin D, and calcium intakes from diet and supplements in relation to maternal characteristics. Data were collected in a subsample of 1186 pregnant women from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, a cohort study including pregnant women recruited from 10 Canadian sites between 2008 and 2011. A food frequency questionnaire was administered to obtain rankings of iron, calcium, and vitamin D intake (16-21 weeks of pregnancy). Intakes from supplements were obtained from a separate questionnaire (6-13 weeks of pregnancy). Women were divided into 2 groups according to the median total intake of each nutrient. Supplement intake was an important contributor to total iron intake (median 74%, interquartile range (IQR) 0%-81%) and total vitamin D intake (median 60%, IQR 0%-73%), while the opposite was observed for calcium (median 18%, IQR 0%-27%). Being born outside of Canada was significantly associated with lower total intakes of iron, vitamin D, and calcium (p ≤ 0.01 for all). Consistent positive indicators of supplement use (iron, vitamin D, and calcium) were maternal age over 30 years and holding a university degree. In conclusion, among Canadian women, the probability of having lower iron, vitamin D, and calcium intakes is higher among those born outside Canada; supplement intake is a major contributor to total iron and vitamin D intakes; and higher education level and age over 30 years are associated with supplement intake.

Maternal and Neonatal Levels of Perfluoroalkyl Substances in Relation to Gestational Weight Gain

Perfluoroalkyl substances (PFASs) are ubiquitous, persistent pollutants widely used in the production of common household and consumer goods. There is a limited body of literature suggesting that these chemicals may alter metabolic pathways and growth trajectories. The relationship between prenatal exposures to these chemicals and gestational weight gain (GWG) has received limited attention. One objective was to analyze the associations among maternal plasma levels of three common perfluoroalkyl substances (perfluorooctanoate (PFOA), perfluorooctanesulfonate (PFOS), perfluorohexanesulfanoate (PFHxS)) and GWG. Additionally, we explored whether GWG was associated with cord blood PFAS levels. This study utilized data collected in the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, a trans-Canada cohort study of 2001 pregnant women. Our analysis quantified associations between (1) maternal PFAS concentrations and GWG and (2) GWG and cord blood PFAS concentrations. Maternal PFOS concentrations were positively associated with GWG (β = 0.39 95% CI: 0.02, 0.75). Interquartile increases in GWG were significantly associated with elevated cord blood PFOA (OR = 1.33; 95% CI: 1.13 to 1.56) and PFOS (OR = 1.20; 95% CI: 1.03 to 1.40) concentrations. No statistically significant associations were observed between GWG and either measure of PFHxS. These findings warrant elucidation of the potential underlying mechanisms.

Exposure to phthalates, bisphenol A and metals in pregnancy and the association with impaired glucose tolerance and gestational diabetes mellitus: The MIREC study

BACKGROUND

Studies from several countries report increases in rates of gestational diabetes mellitus (GDM) over recent decades. Exposure to environmental chemicals could contribute to this trend.

OBJECTIVES

To determine the associations between plasticisers and metals measured in early pregnancy with impaired glucose tolerance (IGT) and GDM in a Canadian pregnancy cohort.

METHODS

Women enrolled in the Maternal-Infant Research on Environmental Chemicals (MIREC) Study were included if they had a singleton delivery and did not have pre-existing diabetes. Eleven phthalate metabolites and total bisphenol A (BPA) were measured in first-trimester urine samples, and four metals (lead, cadmium, mercury and arsenic) were measured in first-trimester blood samples. IGT and GDM were assessed in accordance with standard guidelines by chart review. Chemical concentrations were grouped by quartiles, and associations with outcomes were examined using logistic regression with adjustment for maternal age, race, pre-pregnancy BMI, and education. Restricted cubic spline analysis was performed to help assess linearity and nature of any dose-response relationships.

RESULTS

Of 2001 women recruited into the MIREC cohort, 1274 met the inclusion criteria and had outcome data and biomonitoring data measured for at least one of the chemicals we examined. Elevated odds of GDM were observed in the highest quartile of arsenic exposure (OR = 3.7, 95% CI = 1.4-9.6) in the adjusted analyses. A significant dose-response relationship was observed in a cubic spline model between arsenic and odds of GDM (p < 0.01). No statistically significant associations were observed between phthalates or BPA or other metals with IGT or GDM.

CONCLUSIONS

Our findings add to the growing body of evidence supporting the role of maternal arsenic exposure as a risk factor for gestational diabetes.

Maternal blood metal levels and fetal markers of metabolic function

Exposure to metals commonly found in the environment has been hypothesized to be associated with measures of fetal growth but the epidemiological literature is limited. The Maternal-Infant Research on Environmental Chemicals (MIREC) study recruited 2001 women during the first trimester of pregnancy from 10 Canadian sites. Our objective was to assess the association between prenatal exposure to metals (lead, arsenic, cadmium, and mercury) and fetal metabolic function. Average maternal metal concentrations in 1st and 3rd trimester blood samples were used to represent prenatal metals exposure. Leptin and adiponectin were measured in 1363 cord blood samples and served as markers of fetal metabolic function. Polytomous logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association between metals and both high (≥ 90%) and low (≤ 10%) fetal adiponectin and leptin levels. Leptin levels were significantly higher in female infants compared to males. A significant relationship between maternal blood cadmium and odds of high leptin was observed among males but not females in adjusted models. When adjusting for birth weight z-score, lead was associated with an increased odd of high leptin. No other significant associations were found at the top or bottom 10th percentile in either leptin or adiponectin models. This study supports the proposition that maternal levels of cadmium influence cord blood adipokine levels in a sex-dependent manner. Further investigation is required to confirm these findings and to determine how such findings at birth will translate into childhood anthropometric measures.

A birth cohort study to investigate the association between prenatal phthalate and bisphenol A exposures and fetal markers of metabolic dysfunction

BACKGROUND

Obesity and type-2 diabetes are on the rise and in utero exposure to environmental contaminants is a suspected contributing factor. Our objective was to examine associations between prenatal exposure to potential endocrine disrupting chemicals and markers of fetal metabolic dysfunction.

METHODS

The Maternal-Infant Research on Environmental Chemicals Study (MIREC) recruited 2001 women during the first trimester of pregnancy from 10 Canadian sites. First trimester maternal urine was measured for 11 phthalate metabolites and bisphenol A (BPA). Leptin and adioponectin measured in 1,363 available umbilical cord blood samples served as markers of metabolic function. Restricted cubic spline curves were used to assess the relationship between continuous measures of phthalate and BPA levels and cord blood adipokines. Polytomous logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association between phthalates and BPA and both high (≥90th percentile) and low (≤10th percentile) fetal adiponectin and leptin, adjusting for confounding factors. Analyses were conducted for all subjects, overall, and separately by fetal sex.

RESULTS

Leptin was significantly higher in female than male infants. We observed an inverse, non-linear relationship between BPA and adiponectin among males in the restricted cubic spline and linear regression analysis. Mono-(3-carboxypropyl) (MCPP) was associated with increased odds of high leptin among males in the polytomous logistic regression models (4th quartile OR = 3.5 95% CI: 1.1-11.6).

CONCLUSION

Our findings contribute to the growing body of evidence examining the influence of early life exposure on metabolic regulation and function. Associations between maternal exposure to chemicals and markers of metabolic function appear to be potentially sex specific. However, further investigation is required to determine whether in utero and childhood exposure to BPA and phthalates are associated with metabolic dysfunctions later in life.

Psychosocial stress in pregnancy and preterm birth: associations and mechanisms

AIMS

Psychosocial stress during pregnancy (PSP) is a risk factor of growing interest in the etiology of preterm birth (PTB). This literature review assesses the published evidence concerning the association between PSP and PTB, highlighting established and hypothesized physiological pathways mediating this association.

METHOD

The PubMed and Web of Science databases were searched using the keywords "psychosocial stress", "pregnancy", "pregnancy stress", "preterm", "preterm birth", "gestational age", "anxiety", and "social support". After applying the exclusion criteria, the search produced 107 articles.

RESULTS

The association of PSP with PTB varied according to the dimensions and timing of PSP. Stronger associations were generally found in early pregnancy, and most studies demonstrating positive results found moderate effect sizes, with risk ratios between 1.2 and 2.1. Subjective perception of stress and pregnancy-related anxiety appeared to be the stress measures most closely associated with PTB. Potential physiological pathways identified included behavioral, infectious, neuroinflammatory, and neuroendocrine mechanisms.

CONCLUSIONS

Future research should examine the biological pathways of these different psychosocial stress dimensions and at multiple time points across pregnancy. Culture-independent characterization of the vaginal microbiome and noninvasive monitoring of cholinergic activity represent two exciting frontiers in this research.

Evaluating racial/ethnic variations in outpatient epilepsy care

This study evaluated the quality of epilepsy care in an ambulatory population of a major medical center and determined if there were any racial/ethnic variations. The well-established 'Quality Indicators in Epilepsy Treatment (QUIET)' study dataset was used. Medical record, phone interview, and mail-out survey data of 311 patients with epilepsy were linked and analyzed. Evaluation of care from provider and patient perspectives was performed. Overall, the patients with epilepsy received 40.9% of QI recommended care. The black patients were more likely to receive 50% or more QI recommended care compared with non-Hispanic whites (odds ratio [OR]=2.16, 95% confidence interval [CI] 1.09-4.27). Black patients scored significantly worse than non-Hispanic whites for two patient-reported measures--perceived racial/ethnic disparities (OR=3.14, 95% CI 1.15-8.53) and difficulties getting follow-up appointments (OR=3.37, 95% CI 1.55-7.32). The results indicate the need to evaluate both provider- and patient-centered measures in quality-of-care studies in disparities research.

Emerging risk factors for postpartum depression: serotonin transporter genotype and omega-3 fatty acid status

OBJECTIVE

Depression is a leading cause of disability and hospitalization. Women are at the highest risk of depression during their childbearing years, and the birth of a child may precipitate a depressive episode in vulnerable women. Postpartum depression (PPD) is associated with diminished maternal somatic health as well as health and developmental problems in their offspring. This review focuses on 2 PPD risk factors of emerging interest: serotonin transporter (5-HTT) genotype and omega-3 polyunsaturated fatty acid (n-3 PUFA) status.

METHOD

The MEDLINE, PubMed, and Web of Science databases were searched using the key words postpartum depression, nutrition, omega-3 fatty acids, and serotonin transporter gene. Studies were also located by reviewing the reference lists of selected articles.

RESULTS

Seventy-five articles were identified as relevant to this review. Three carefully conducted studies reported associations between the 5-HTT genotype and PPD. As well, there is accumulating evidence that n-3 PUFA intake is associated with risk of PPD. Preliminary evidence suggests that there could be an interaction between these 2 emerging risk factors. However, further studies are required to confirm such an interaction and to elucidate the underlying mechanisms.

CONCLUSIONS

Evidence to date supports a research agenda clarifying the associations between n-3 PUFAs, the 5-HTT genotype, and PPD. This is of particular interest owing to the high prevalence of poor n-3 PUFA intake among women of childbearing age and the consequent potential for alternative preventive measures and treatments for PPD.

Validation of self-reported epilepsy for purposes of community surveillance

We evaluated the validity of questions designed to identify lifetime and active epilepsy, medication use, and seizure occurrence on population-based surveys. Subjects were interviewed by telephone, and responses were compared with information in their medical records. Prevalence, sensitivity, specificity, and positive predictive value (PPV) were calculated. The prevalence of ever having been diagnosed with epilepsy was 3.1% by self-report and 2.7% by medical record review. Sensitivity was 84.2%, specificity was 99.2%, and PPV was 73.5% for self-reported lifetime epilepsy, and values were similar for active epilepsy. By comparison, sensitivity was higher and specificity was lower for epilepsy medication use and seizure occurrence. The PPV for seizure occurrence was substantially higher for a recall period of 12 months than for 3 months. These results compare favorably with results for other chronic conditions, such as diabetes and arthritis, and indicate that questionnaires can be used to identify epilepsy at a population level.