Comparison of sample characteristics in two pregnancy cohorts: community-based versus population-based recruitment methods

Prevalence of Diabetic Retinopathy in Indigenous and Non-Indigenous Australians: A Systematic Review and Meta-analysis

TOPIC

This systematic review and meta-analysis summarizes evidence relating to the prevalence of diabetic retinopathy (DR) among Indigenous and non-Indigenous Australians.

CLINICAL RELEVANCE

Indigenous Australians suffer disproportionately from diabetes-related complications. Exploring ethnic variation in disease is important for equitable distribution of resources and may lead to identification of ethnic-specific modifiable risk factors. Existing DR prevalence studies comparing Indigenous and non-Indigenous Australians have shown conflicting results.

METHODS

This study was conducted following Joanna Briggs Institute guidance on systematic reviews of prevalence studies (PROSPERO ID: CRD42022259048). We performed searches of Medline (Ovid), EMBASE, and Web of Science until October 2021, using a strategy designed by an information specialist. We included studies reporting DR prevalence among diabetic patients in Indigenous and non-Indigenous Australian populations. Two independent reviewers performed quality assessments using a 9-item appraisal tool. Meta-analysis and meta-regression were performed using double arcsine transformation and a random-effects model comparing Indigenous and non-Indigenous subgroups.

RESULTS

Fifteen studies with 8219 participants met criteria for inclusion. The Indigenous subgroup scored lower on the appraisal tool than the non-Indigenous subgroup (mean score 50% vs. 72%, P = 0.04). In the unadjusted meta-analysis, DR prevalence in the Indigenous subgroup (30.2%; 95% confidence interval [CI], 24.9-35.7) did not differ significantly (P = 0.17) from the non-Indigenous subgroup (23.7%; 95% CI, 16.8-31.4). After adjusting for age and quality, DR prevalence was higher in the Indigenous subgroup (P < 0.01), with prevalence ratio point estimates ranging from 1.72 to 2.58, depending on the meta-regression model. For the secondary outcomes, prevalence estimates were higher in the Indigenous subgroup for diabetic macular edema (DME) (8.7% vs. 2.7%, P = 0.02) and vision-threatening DR (VTDR) (8.6% vs. 3.0%, P = 0.03) but not for proliferative DR (2.5% vs. 0.8%, P = 0.07).

CONCLUSIONS

Indigenous studies scored lower for methodological quality, raising the possibility that systematic differences in research practices may be leading to underestimation of disease burden. After adjusting for age and quality, we found a higher DR prevalence in the Indigenous subgroup. This contrasts with a previous review that reported the opposite finding of lower DR prevalence using unadjusted pooled estimates. Future epidemiological work exploring DR burden in Indigenous communities should aim to address methodological weaknesses identified by this review.

The Alberta Pregnancy Outcomes and Nutrition (APrON) longitudinal study: cohort profile and key findings from the first three years

PURPOSE

The objectives of the ongoing Canadian longitudinal cohort called the Alberta Pregnancy Outcomes and Nutrition (APrON) study are to: (1) determine the relationship between maternal nutrient intake and status before, during, after pregnancy, and (a) maternal mental health, (b) pregnancy and birth outcomes, and (c) infant/child neurodevelopment and behavior; (2) identify maternal mental health and nutrient predictors of child behaviour; and (3) establish a DNA biobank to explore genomic predictors of children's neurodevelopment and behavior. The purpose of this paper is to describe the participants, measures, and key findings on maternal and paternal mental health, maternal nutrition, and child outcomes to when children are 3 years of age.

PARTICIPANTS

Participants included mothers and their children (n=2189) and mothers' partners (usually fathers; n=1325) from whom data were collected during the period from pregnancy to when children were 3 years of age, in Alberta, Canada. More than 88% of families have been retained to take part in completed data collection at 8 years of age.

FINDINGS TO DATE

Data comprise: questionnaires completed by pregnant women/mothers and their partners on mothers', fathers' and children's health; dietary interviews; clinical assessments; linkage to hospital obstetrical records; and biological samples such as DNA. Key findings on mental health, nutrition and child outcomes are presented. APrON women who consumed more selenium and omega-3 were less likely to develop symptoms of perinatal depression. Higher prenatal consumption of choline rich foods such as eggs and milk were recommended as was vitamin D supplementation for both mothers and children to meet guidelines. Couples in which both mothers and fathers were affected by perinatal depression reported lower incomes and higher maternal prenatal depressive symptoms and lower support from fathers postnatally and their children presented with the most behavioural problems. Maternal experiences of early adversity predicted increased likelihood of perinatal depression and anxiety and children's behavioural problems.

FUTURE PLANS

The APrON cohort offers a unique opportunity to advance understanding of the developmental origins of health and disease. There is a planned follow-up to collect data at 12 years of age.

Sleep and the gut microbiota in preschool-aged children

Sleep plays a significant role in the mental and physical development of children. Emerging evidence in animals and human adults indicates a relationship between sleep and the gut microbiota; however, it is unclear whether the sleep of preschoolers during a key developmental period, associates with features of their gut microbiota. The objective of this study was to assess the relationship between sleep and gut microbiota in preschool-aged children (4.37 ± 0.48 years, n = 143). Sleep measures included total night-time sleep (TST), sleep efficiency (SE), and wake-time after sleep onset (WASO) assessed using actigraphy. Beta-diversity differences between children with low and high TST (p = .048) suggest gut microbiota community differences. Particularly, relative abundance of Bifidobacterium was higher in the high TST group and Bacteroides, was higher in children who had greater SE and less WASO (LDA score >2). In contrast, some Lachnospiraceae members including Blautia and Coprococcus 1 were associated with shorter night-time sleep duration and less efficiency, respectively. We also found a group of fecal metabolites, including specific neuroactive compounds and immunomodulating metabolites were associated with greater sleep efficiency and less time awake at night. Notably, tryptophan and its metabolizing products were higher in children who had higher SE or lower WASO (LDA score >2); concentration of propionate was higher in children with less WASO (p = .036). Overall, our results reveal a novel association between sleep and gut microbiota in preschool-aged children. Longer night-time sleep and greater sleep efficiency were associated with specific commensal bacteria that may regulate sleep through modulating neurotransmitter metabolism and the immune system.

Involving and engaging pregnant women in maternity-related research: reflections on an innovative approach

BACKGROUND

Meaningful public involvement in maternity research remains challenging, partly due to the transient nature of pregnancy. This paper reflects on the development, implementation and simple evaluation of an innovative and inclusive approach to engaging and involving pregnant and early postnatal women in research.

METHODS

Between January and February 2018, a Research Fellow in Maternity Care, a Professor of Evidence Based Maternity Care, and a Patient and Public Involvement Lead convened for a number of meetings to discuss how public involvement and engagement might be improved for pregnancy-related research. A stakeholder group was created, including a local community matron, a community engagement officer at a local children's centre, public contributors, and senior members of the Maternal and Child Health theme of the West Midlands Collaboration for Leadership in Applied Health Research and Care (CLAHRC WM). The team worked together to develop a format for Yoga for Bump sessions: a free 90-min session, offered weekly, which included research involvement/engagement, pregnancy yoga, and a 'question and answer' session with a midwife.

RESULTS

A total of 67 women from two local communities in Birmingham attended Yoga for Bump sessions, which ran between May and December of 2018. Evaluation of the sessions suggested benefits to both women and researchers: it created mutually beneficial relationships between contributors and researchers, provided opportunities for women to engage and get involved in research that was directly relevant to them, and provided a convenient and efficient way for researchers to involve and engage pregnant women from diverse backgrounds in their research. Unintended benefits included self-reported improvements in women's health and wellbeing.

CONCLUSIONS

Yoga for Bump demonstrates an innovative approach to engaging and involving pregnant and early postnatal women; combining a free exercise class with healthcare advice and opportunities to engage with and be involved in research, and demonstrating mutual benefits for those involved. This model has the potential to be replicated elsewhere to support inclusive public involvement in pregnancy-related research. Further work is needed to design and evaluate similar approaches to involvement/engagement and explore potential funding avenues to enhance sustainability.

Data harmonization and data pooling from cohort studies: a practical approach for data management

Data pooling from pre-existing datasets can be useful to increase study sample size and statistical power in order to answer a research question. However, individual datasets may contain variables that measure the same construct differently, posing challenges for data pooling. Variable harmonization, an approach that can generate comparable datasets from heterogeneous sources, can address this issue in some circumstances. As an illustrative example, this paper describes the data harmonization strategies that helped generate comparable datasets across two Canadian pregnancy cohort studies: All Our Families; and the Alberta Pregnancy Outcomes and Nutrition. Variables were harmonized considering multiple features across the datasets: the construct measured; question asked/response options; the measurement scale used; the frequency of measurement; timing of measurement, and the data structure. Completely matching, partially matching, and completely un-matching variables across the datasets were determined based on these features. Variables that were an exact match were pooled as is. Partially matching variables were harmonized or processed under a common format across the datasets considering the frequency of measurement, the timing of measurement, the measurement scale used, and response options. Variables that were completely unmatching could not be harmonized into a single variable. The variable harmonization strategies that were used to generate comparable cohort datasets for data pooling are applicable to other data sources. Future studies may employ or evaluate these strategies, which permit researchers to answer novel research questions in a statistically efficient, timely, and cost-efficient manner that could not be achieved using a single data source.

Paternal adverse childhood experiences: Associations with infant DNA methylation

Adverse childhood experiences (ACEs), or cumulative childhood stress exposures, such as abuse, neglect, and household dysfunction, predict later health problems in both the exposed individuals and their offspring. One potential explanation suggests exposure to early adversity predicts epigenetic modification, especially DNA methylation (DNAm), linked to later health. Stress experienced preconception by mothers may associate with DNAm in the next generation. We hypothesized that fathers' exposure to ACEs also associates with their offspring DNAm, which, to our knowledge, has not been previously explored. An epigenome-wide association study (EWAS) of blood DNAm (n = 45) from 3-month-old infants was regressed onto fathers' retrospective ACEs at multiple Cytosine-phosphate-Guanosine (CpG) sites to discover associations. This accounted for infants' sex, age, ethnicity, cell type proportion, and genetic variability. Higher ACE scores associated with methylation values at eight CpGs. Post-hoc analysis found no contribution of paternal education, income, marital status, and parental postpartum depression, but did with paternal smoking and BMI along with infant sleep latency. These same CpGs also contributed to the association between paternal ACEs and offspring attention problems at 3 years. Collectively, these findings suggested there were biological associations with paternal early life adversity and offspring DNAm in infancy, potentially affecting offspring later childhood outcomes.

The role of maternal nutrition during pregnancy in the intergenerational transmission of childhood adversity

Adverse childhood experiences (ACEs) of a woman can lead to dysregulated hypothalamus-pituitary-adrenal (HPA) axis during pregnancy, which can in turn adversely affect her offspring HPA axis function. Choline and docosahexaenoic acid (DHA) are dietary factors with the potential to favorably modify the stress response system. The current study aimed to investigate whether maternal choline intake and DHA status moderate the effects of maternal ACEs exposure on maternal and infant HPA axes function. Participants were a sub-sample of the prospective longitudinal Alberta Pregnancy Outcomes and Nutrition (APrON) study consisting of 340 mothers and 238 infants. We collected data on maternal ACEs, maternal choline intake (24-hour dietary recall) and serum phospholipid DHA concentrations (at each trimester). Women self-collected saliva samples on two consecutive days (at waking, +30 min, 1100 h, and 2100 h) in each trimester to calculate the cortisol awakening response (CAR) and total daytime cortisol. Infants' salivary cortisol was measured before and after (20, and 40 min) exposure to a blood draw stressor 3 months postpartum. During pregnancy, choline intake moderated (reduced) the association between maternal ACEs and CAR (β = -0.003; 95% CI -0.006, -0.003), but not total daytime cortisol. DHA status did not moderate the association between ACEs and CAR or total daytime cortisol. Choline intake also moderated (reduced) the association between maternal CAR and infant cortisol during a stress task (β = -0.0001; 95% CI -0.0002, -0.00003). Maternal DHA status revealed no modifying effects on these associations. Our findings suggest that maternal choline intake, but not DHA status, can buffer the associations between ACEs and maternal HPA axis, as well as maternal and infant HPA axes function.

Characteristics of Environmental influences on Child Health Outcomes (ECHO) Cohorts Recruited During Pregnancy

PURPOSE

The objective of this study was to characterize the study designs, recruitment strategies, and other study characteristics among cohorts that initiated during pregnancy as part of the Environmental influences on Child Health Outcomes (ECHO) program.

METHODS

ECHO research programs (cohorts) were reviewed. Only those who had or were currently recruiting during pregnancy were surveyed in 2018 about research recruitment strategies (participant incentives, study burden, community collaboration, and cultural adaptations). Data are presented with cohort characteristics (location, inclusion and exclusion criteria, sociodemographics, medical information, behavioral factors, and biospecimens).

RESULTS

Forty-seven of the 84 ECHO pediatric cohorts recruited during pregnancy. Findings demonstrate various recruitment strategies, domains of data collection, and biospecimen collection are all characteristics of successful cohorts.

CLINICAL IMPLICATIONS

These data that include over 50,000 children from families across the country, many in underserved areas, will be used for research with the potential to lead to profound policy changes. Prenatal conditions such as maternal age, obesity, depression, and drug use can be examined using study data, including biological markers, from pregnancy through childbirth and into childhood and will inform national policies on the role of early life exposures and underlying mechanisms of disease progression.

Assessment of anxiety during pregnancy: are existing multiple anxiety scales suitable and comparable in measuring anxiety during pregnancy?

BACKGROUND

This study examined the performance of multiple anxiety scales in measuring anxiety during pregnancy, an important issue due to the possible effect of pregnancy-related symptoms on the measurement of anxiety.

METHODS

Secondary data on anxiety, measured by the State-Trait Anxiety Inventory-State (STAI-S) 20-item and six-item scales, the Edinburgh Postnatal Depression Scale-Anxiety Subscale (EPDS-3A) and the Symptoms Checklist-90-Anxiety Subscale (SCL-90), were obtained from two pregnancy cohort studies. Both cohorts completed the EPDS-3A, while 3341 women completed the STAI-S and 2187 women completed the SCL-90, with 231 women participating in both cohorts. Data were analyzed using confirmatory factor analysis and Spearman correlation.

RESULTS

The STAI-6 had adequate model fit, while the STAI-20 and the SCL-90 had inadequate model fit. Model fitness for the EPDS-3A could not be assessed due to its low number of items. The correlation between the STAI-20 and STAI-6 was excellent (r = 0.93). The correlation of EPDS-3A with other anxiety scales was low to moderate (r (STAI-20) = 0.57, r (STAI-6) = 0.53 and r (SCL-90) = 0.44). The correlation of SCL-90 with both STAI-20 and STAI-6 was low (r < 0.50).

CONCLUSION

Findings indicate that these scales do not measure anxiety as a single dimension and that these scales are incomparable and may conceptualize anxiety differently.

Recruitment and retention of pregnant women in prospective birth cohort studies: A scoping review and content analysis of the literature

Longitudinal cohort studies present unique methodological challenges, especially when they focus on vulnerable populations, such as pregnant women. The purpose of this review is to synthesize the existing knowledge on recruitment and retention (RR) of pregnant women in birth cohort studies and to make recommendations for researchers to improve research engagement of this population. A scoping review and content analysis were conducted to identify facilitators and barriers to the RR of pregnant women in cohort studies. The search retrieved 574 articles, with 38 meeting eligibility criteria and focused on RR among English-speaking, adult women, who are pregnant or in early postpartum period, enrolled in birth cohort studies. Selected studies were birth cohort (including longitudinal) (n = 20), feasibility (n = 14), and other (n = 4) non-interventional study designs. The majority were from low-risk populations. Abstracted data were coded according to emergent theme clusters. The majority of abstracted data (79%) focused on recruitment practices, with only 21% addressing retention strategies. Overall, facilitators were reported more often (75%) than barriers (25%). Building trusting relationships and employing diverse recruitment methods emerged as major recruitment facilitators; major barriers included heterogeneous participant reasons for refusal and cultural factors. Key retention facilitators included flexibility with scheduling, frequent communication, and culturally sensitive practices, whereas participant factors such as loss of interest, pregnancy loss, relocation, multiple caregiver shifts, and substance use/psychiatric problems were cited as major barriers. Better understanding of facilitators and barriers of RR can help enhance the internal and external validity of future birth/pre-birth cohorts. Strategies presented in this review can help inform investigators and funding agencies of best practices for RR of pregnant women in longitudinal studies.

Neighbourhood socioeconomic status modifies the association between anxiety and depression during pregnancy and preterm birth: a Community-based Canadian cohort study

OBJECTIVE

This study examined the association of anxiety alone, depression alone and the presence of both anxiety and depression with preterm birth (PTB) and further examined whether neighbourhood socioeconomic status (SES) modified this association.

DESIGN

Cohort study using individual-level data from two community-based prospective pregnancy cohort studies (All Our Families; AOF) and Alberta Pregnancy Outcomes and Nutrition (APrON) and neighbourhood SES data from the 2011 Canadian census.

SETTING

Calgary, Alberta, Canada.

PARTICIPANTS

Overall, 5538 pregnant women who were <27 weeks of gestation and >15 years old were enrolled in the cohort studies between 2008 and 2012. 3341 women participated in the AOF study and 2187 women participated in the APrON study, with 231 women participated in both studies. Women who participated in both studies were only counted once.

PRIMARY AND SECONDARY OUTCOME MEASURES

PTB was defined as delivery prior to 37 weeks of gestation. Depression was defined as an Edinburgh Postnatal Depression Scale (EPDS) score of ≥13, anxiety was defined as an EPDS-anxiety subscale score of ≥6, and the presence of both anxiety and depression was defined as meeting both anxiety and depression definitions.

RESULTS

Overall, 7.3% of women delivered preterm infants. The presence of both anxiety and depression, but neither of these conditions alone, was significantly associated with PTB (OR 1.6, 95% CI 1.1 to 2.3) and had significant interaction with neighbourhood deprivation (p=0.004). The predicted probability of PTB for women with both anxiety and depression was 10.0%, which increased to 15.7% if they lived in the most deprived neighbourhoods and decreased to 1.4% if they lived in the least deprived neighbourhoods.

CONCLUSIONS

Effects of anxiety and depression on risk of PTB differ depending on where women live. This understanding may guide the identification of women at increased risk for PTB and allocation of resources for early identification and management of anxiety and depression.

Breastfeeding rates in immigrant and non-immigrant women: A systematic review and meta-analysis

Breastfeeding benefits mothers and infants. Although immigration in many regions has increased in the last three decades, it is unknown whether immigrant women have better breastfeeding outcomes than non-immigrants. The aim of this study was to conduct a systematic review and meta-analysis to determine whether breastfeeding rates differ between immigrant and non-immigrant women. We searched Medline, Embase, PsycINFO, CINAHL and Google Scholar, 1950 to 2016. We included peer-reviewed cross-sectional and cohort studies of women aged ≥16 years that assessed and compared breastfeeding rates in immigrant and non-immigrant women. Two independent reviewers extracted data using predefined standard procedures. The analysis included 29 studies representing 1,539,659 women from 14 countries. Immigrant women were more likely than non-immigrants to initiate any (exclusive or partial) breastfeeding (pooled adjusted prevalence ratio 1.13, 95% confidence interval [CI] 1.07-1.19; 11 studies). Exclusive breastfeeding initiation was higher but borderline significant (adjusted prevalence ratio 1.20, 95% CI 1.00-1.45; 5 studies, p = 0.056). Immigrant women were more likely than non-immigrants to continue any breastfeeding between 12- and 24-week postpartum (pooled adjusted risk ratio 2.04, 95% CI 1.79-2.32; 3 studies) and > 24 weeks (adjusted risk ratio 1.33, 95% CI 1.02-1.73; 6 studies) but not exclusive breastfeeding. Immigrant women are more likely than non-immigrants to initiate and maintain any breastfeeding, but exclusive breastfeeding remains a challenge for both immigrants and non-immigrants. Social and cultural factors need to be considered to understand the extent to which immigrant status is an independent predictor of positive breastfeeding practices.

Does neighborhood socioeconomic status predict the risk of preterm birth? A community-based Canadian cohort study

OBJECTIVE

This study developed and internally validated a predictive model for preterm birth (PTB) to examine the ability of neighbourhood socioeconomic status (SES) to predict PTB.

DESIGN

Cohort study using individual-level data from two community-based prospective pregnancy cohort studies (All Our Families (AOF) and Alberta Pregnancy Outcomes and Nutrition (APrON)) and neighbourhood SES data from the 2011 Canadian census.

SETTING

Calgary, Alberta, Canada.

PARTICIPANTS

Pregnant women who were <24 weeks of gestation and >15 years old were enrolled in the cohort studies between 2008 and 2012. Overall, 5297 women participated in at least one of these cohorts: 3341 women participated in the AOF study, 2187 women participated in the APrON study and 231 women participated in both studies. Women who participated in both studies were only counted once.

PRIMARY AND SECONDARY OUTCOME MEASURES

PTB (delivery prior to 37 weeks of gestation).

RESULTS

The rates of PTB in the least and most deprived neighbourhoods were 7.54% and 10.64%, respectively. Neighbourhood variation in PTB was 0.20, with an intra-class correlation of 5.72%. Neighbourhood SES, combined with individual-level predictors, predicted PTB with an area under the receiver-operating characteristic curve (AUC) of 0.75. The sensitivity was 91.80% at a low-risk threshold, with a high false-positive rate (71.50%), and the sensitivity was 5.70% at a highest risk threshold, with a low false-positive rate (0.90%). An agreement between the predicted and observed PTB demonstrated modest model calibration. Individual-level predictors alone predicted PTB with an AUC of 0.60.

CONCLUSION

Although neighbourhood SES combined with individual-level predictors improved the overall prediction of PTB compared with individual-level predictors alone, the detection rate was insufficient for application in clinical or public health practice. A prediction model with better predictive ability is required to effectively find women at high risk of preterm delivery.

Sharing longitudinal, non-biological birth cohort data: a cross-sectional analysis of parent consent preferences

BACKGROUND

Mandates abound to share publicly-funded research data for reuse, while data platforms continue to emerge to facilitate such reuse. Birth cohorts (BC) involve longitudinal designs, significant sample sizes and rich and deep datasets. Data sharing benefits include more analyses, greater research complexity, increased opportunities for collaboration, amplification of public contributions, and reduced respondent burdens. Sharing BC data involves significant challenges including consent, privacy, access policies, communication, and vulnerability of the child. Research on these issues is available for biological data, but these findings may not extend to BC data. We lack consensus on how best to approach these challenges in consent, privacy, communication and autonomy when sharing BC data. We require more stakeholder engagement to understand perspectives and generate consensus.

METHODS

Parents participating in longitudinal birth cohorts completed a web-based survey investigating consent preferences for sharing their, and their child's, non-biological research data. Results from a previous qualitative inquiry informed survey development, and cognitive interviewing methods (n = 9) were used to improve the question quality and comprehension. Recruitment was via personalized email, with email and phone reminders during the 14-day window for survey completion.

RESULTS

Three hundred and forty-six of 569 parents completed the survey in September 2014 (60.8%). Participants preferred consent processes for data sharing in future independent research that were less-active (i.e. no consent or opt-out). Parents' consent preferences are associated with their communication preferences. Twenty percent (20.2%) of parents generally agreed that their child should provide consent to continue participating in research at age 12, while 25.6% felt decision-making on sharing non-biological research data should begin at age 18.

CONCLUSIONS

These finding reflect the parenting population's preference for less project-specific permission when research data is non-biological and de-identified and when governance practices are highly detailed and rigourous. Parents recognize that children should become involved in consent for secondary data use, but there is variability regarding when and how involvement occurs. These findings emphasize governance processes and participant notification rather than project-specific consent for secondary use of de-identified, non-biological data. Ultimately, parents prefer general consent processes for sharing de-identified, non-biological research data with ultimate involvement of the child.

Social buffering of the maternal and infant HPA axes: Mediation and moderation in the intergenerational transmission of adverse childhood experiences

Supportive social relationships can reduce both psychological and physiological responses to stressful experiences. Recently, studies have also assessed the potential for social relationships to buffer the intergenerational transmission of stress. The majority of these studies, however, have focussed on social learning as a mechanism responsible for the intergenerational transmission of stress. Evidence of biological mechanisms is lacking. The objective of the current study was, therefore, to determine whether the association between maternal adverse childhood experiences (ACEs) and infant hypothalamic-pituitary-adrenal (HPA) axis function is mediated by maternal HPA axis function during pregnancy and moderated by social support. Data were from 243 mother-infant dyads enrolled in a prospective longitudinal cohort (the Alberta Pregnancy Outcomes and Nutrition Study). Maternal history of ACEs was retrospectively assessed while maternal perceived social support and salivary cortisol were assessed prospectively at 6-22 weeks gestation (Time 1) and 27-37 weeks gestation (Time 2), and infant cortisol reactivity to a laboratory stressor and maternal perceived social support were assessed at 5-10 months postnatal (Time 3). Results revealed that maternal HPA axis function during pregnancy mediated the effects of maternal ACEs on infant HPA axis reactivity, suggesting that the maternal HPA axis is a mechanism by which maternal early life stress is transmitted to offspring. Furthermore, social support in the prenatal and postnatal periods moderated the cascade from maternal ACEs to infant HPA axis reactivity. Specifically, prenatal social support moderated the association between ACEs and maternal HPA axis function during pregnancy, and postnatal social support moderated the association between maternal HPA axis function and infant cortisol reactivity. These findings highlight the social sensitivity of the HPA axis and suggest the utility of social relationships as an intervention target to reduce the effects of maternal early life stress on infant outcomes.

Engaging pregnant women in observational research: a qualitative exploratory study

Background

Recruitment of pregnant women to population health research can be challenging, especially if the research topic is sensitive. While many pregnant women may be inherently interested in research about pregnancy, there is the possibility that the nature and timing of the project may give rise to anxiety in some women, especially if the topic is sensitive or it brings about new awareness of potential pregnancy complications. Research staff undertaking recruitment need to be skilled at strategies to manage the environment, and have well developed communication and interpersonal skills to explain and promote the study and facilitate each woman’s informed decision-making regarding participation.

However, the skills needed by recruitment staff to successfully engage pregnant women with a research topic are not well understood. This study aimed to address this evidence gap by providing insight into the dynamics between a pregnant woman and recruitment staff at the time of the offer to participate in an observational study about alcohol use in pregnancy.

Methods

Naturalistic inquiry guided a qualitative exploratory descriptive approach. Experienced recruitment staff from the Asking Questions about Alcohol in Pregnancy (AQUA) study (Muggli et al., BMC Pregnancy Childbirth 14:302, 2014) participated in individual semi-structured interviews and were asked about their experiences and approaches to engaging pregnant women. Interviews were transcribed verbatim and analysed using inductive content analysis.

Results

Pregnant women brought with them an inherent interest or disinterest in alcohol research, or in research in general, which formed the basis for engagement. Women responded favourably to the invitation to participate being delivered without pressure, and as part of a two-way conversation. Engagement with a sensitive topic such as alcohol use in pregnancy was facilitated by a non-judgmental and non-targeted approach. Influences such as privacy, distractions, partner’s opinion, time factors and level of clinical support either facilitated or hindered a woman’s engagement with the research.

Conclusions

These results provide an in-depth explanation of barriers and enablers to recruitment of pregnant women in antenatal clinics to studies that may inform strategies and the training of recruitment staff.

Nursing Child Assessment Satellite Training Parent-Child Interaction Scales: Comparing American and Canadian Normative and High-Risk Samples

PURPOSE

Many nurses rely on the American Nursing Child Assessment Satellite Training (NCAST) Parent-Child Interaction (PCI) Teaching and Feeding Scales to identify and target interventions for families affected by severe/chronic stressors (e.g. postpartum depression (PPD), intimate partner violence (IPV), low-income). However, the NCAST Database that provides normative data for comparisons may not apply to Canadian families. The purpose of this study was to compare NCAST PCI scores in Canadian and American samples and to assess the reliability of the NCAST PCI Scales in Canadian samples.

METHODS

This secondary analysis employed independent samples t-tests (p < 0.005) to compare PCI between the American NCAST Database and Canadian high-risk (families with PPD, exposure to IPV or low-income) and community samples. Cronbach's alphas were calculated for the Canadian and American samples.

RESULTS

In both American and Canadian samples, belonging to a high-risk population reduced parents' abilities to engage in sensitive and responsive caregiving (i.e. healthy serve and return relationships) as measured by the PCI Scales. NCAST Database mothers were more effective at executing caregiving responsibilities during PCI compared to the Canadian community sample, while infants belonging to the Canadian community sample provided clearer cues to caregivers during PCI compared to those of the NCAST Database. Internal consistency coefficients for the Canadian samples were generally acceptable.

CONCLUSIONS

The NCAST Database can be reliably used for assessing PCI in normative and high-risk Canadian families.

PRACTICAL IMPLICATIONS

Canadian nurses can be assured that the PCI Scales adequately identify risks and can help target interventions to promote optimal parent-child relationships and ultimately child development.

The prevalence of antenatal and postnatal co-morbid anxiety and depression: a meta-analysis

To date, the precise prevalence of co-morbidity of anxiety and depression in the perinatal period is not well known. We aimed to estimate the prevalence of co-morbid anxiety and depression in the antenatal and postnatal periods. Systematic searches of multiple electronic databases were conducted for studies published between January 1950 and January 2016. We included 66 (24 published and 42 unpublished) studies incorporating 162 120 women from 30 countries. Prevalence of self-reported antenatal anxiety symptoms and mild to severe depressive symptoms was 9.5% [95% confidence interval (CI) 7.8-11.2, 17 studies, n = 25 592] and of co-morbid anxiety symptoms and moderate/severe depressive symptoms was 6.3% (95% CI 4.8-7.7, 17 studies, n = 27 270). Prevalence of a clinical diagnosis of any antenatal anxiety disorder and depression was 9.3% (95% CI 4.0-14.7, 10 studies, n = 3918) and of co-morbid generalized anxiety disorder and depression was 1.7% (95% CI 0.2-3.1, three studies, n = 3085). Postnatally between 1 and 24 weeks postpartum, the prevalence of co-morbid anxiety symptoms and mild to severe depressive symptoms was 8.2% (95% CI 6.5-9.9, 15 studies, n = 14 731), while co-morbid anxiety symptoms and moderate/severe depressive symptoms was 5.7% (95% CI 4.3-7.1, 13 studies, n = 20 849). The prevalence of a clinical diagnosis of co-morbid anxiety and depression was 4.2% (95% CI 1.9-6.6, eight studies, n = 3251). Prevalence rates did not differ with regard to year of publication, country income, selection bias and attrition bias. The results suggest that co-morbid perinatal anxiety and depression are prevalent and warrant clinical attention given the potential negative child developmental consequences if left untreated. Further research is warranted to develop evidence-based interventions for prevention, identification and treatment of this co-morbidity.

Biological embedding of perinatal social relationships in infant stress reactivity

Whereas significant advances have been made in understanding how exposure to early adversity "gets under the skin" of children to result in long term changes in developmental outcomes, the processes by which positive social relationships become biologically embedded remain poorly understood. The aim of this study was to understand the pathways by which maternal and infant social environments become biologically embedded in infant cortisol reactivity. Two hundred seventy-two pregnant women and their infants were prospectively assessed during pregnancy and at 6 months postpartum. In serial mediation analyses, higher perceived social support from partners during pregnancy was associated with lower infant cortisol reactivity or larger decreases in cortisol in response to a stressor at 6 months of age via lower self-reported prenatal maternal depression and higher mother-infant interaction quality. The findings add to our understanding of how perinatal social relationships become biologically embedded in child development.

ADHD, comorbid disorders and psychosocial functioning: How representative is a child cohort study? Findings from a national patient registry

BACKGROUND

Cohort studies often report findings on children with Attention Deficit Hyperactivity Disorder (ADHD) but may be biased by self-selection. The representativeness of cohort studies needs to be investigated to determine whether their findings can be generalised to the general child population. The aim of the present study was to examine the representativeness of child ADHD in the Norwegian Mother and Child Cohort Study (MoBa).

METHODS

The study population was children born between January 1, 2000 and December 31, 2008 registered with hyperkinetic disorders (hereafter ADHD) in the Norwegian Patient Registry during the years 2008-2013, and two groups of children with ADHD were identified in: 1. MoBa and 2. The general child population. We used the multiaxial International Classification of Diseases (ICD-10) and compared the proportions of comorbid disorders (axes I-III), abnormal psychosocial situations (axis V) and child global functioning (axis VI) between these two groups. We also compared the relative differences in the multiaxial classifications for boys and girls and for children with/without axis I comorbidity, respectively in these two groups of children with ADHD.

RESULTS

A total of 11 119 children were registered with ADHD, with significantly fewer in MoBa (1.45%) than the general child population (2.11%), p < 0.0001. The proportions of comorbid axis I, II, and III disorders were low, with no significant group differences. Compared with the general child population with ADHD, children with ADHD in MoBa were registered with fewer abnormal psychosocial situations (axis V: t = 7.63, p < .0001; d = -.18) and better child global functioning (axis VI: t = 7.93, p < 0.0001; d = .17). When analysing relative differences in the two groups, essentially the same patterns were found for boys and girls and for children with/without axis I comorbidity.

CONCLUSIONS

Self-selection was found to affect the proportions of ADHD, psychosocial adversity and child global functioning in the cohort. However, the differences from the general population were small. This indicates that studies on ADHD and multiaxial classifications in MoBa, as well as other cohort studies with similar self-selection biases, may have reasonable generalisability to the general child population.

Successful Strategies for Practice-Based Recruitment of Racial and Ethnic Minority Pregnant Women in a Randomized Controlled Trial: the IDEAS for a Healthy Baby Study

BACKGROUND

Racial/ethnic minority patients are often underrepresented in clinical trials. Efforts to address barriers to participation may improve representation, thus enhancing our understanding of how research findings apply to more diverse populations.

METHODS

The IDEAS (Information, Description, Education, Assistance, and Support) for a Healthy Baby study was a randomized controlled trial (RCT) of an intervention to reduce barriers to using publicly reported quality data for low-income, racial/ethnic minority women. We used strategies grounded in a health equity framework to address barriers to recruitment and retention in three domains: preparation, process, and patient-centeredness. "Preparation" included teaching study staff about health inequities, role-playing skills to develop rapport and trust, and partnering with clinic staff. "Processes" included use of electronic registration systems to pre-screen potential candidates and determine when eligible participants were in clinic and an electronic database to track patients through the study. Use of a flexible protocol, stipends, and consideration of literacy levels promoted "patient-centeredness."

RESULTS

We anticipated needing to recruit 800 women over 18 months to achieve a completion goal of 650. Using the recruitment and retention strategies outlined above, we recruited 746 women in 15 months, achieving higher recruitment (87.1 %) and retention rates (97.3 %) than we had anticipated.

DISCUSSION

These successful recruitment and retention strategies used for a large RCT promoted inclusivity and accessibility. Researchers seeking to recruit racial and ethnic minority pregnant women in similar settings may find the preparation, process, and patient-centered strategies used in this study applicable for their own studies.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01784575 , 1R21HS021864-01.

Urinary bisphenol A is associated with dysregulation of HPA-axis function in pregnant women: Findings from the APrON cohort study

BACKGROUND

Bisphenol A (BPA) is associated with dysregulation of hypothalamic-pituitary-adrenal (HPA) axis activity in rodents, but evidence in humans is lacking.

OBJECTIVE

To determine whether BPA exposure during pregnancy is associated with dysregulation of the HPA-axis, we examined the association between urinary BPA concentrations and diurnal salivary cortisol in pregnant women. Secondary analyses investigated whether the association between BPA and cortisol was dependent on fetal sex.

METHODS

Diurnal salivary cortisol and urinary BPA were collected during pregnancy from 174 women in a longitudinal cohort study, the Alberta Pregnancy Outcomes and Nutrition (APrON) study. Associations between BPA and daytime cortisol and the cortisol awakening response (CAR) were estimated using mixed models after adjusting for covariates.

RESULTS

Higher concentrations of total BPA uncorrected for urinary creatinine were associated with dysregulation of the daytime cortisol pattern, including reduced cortisol at waking, β=-.055, 95% CI (-.100, -.010) and a flatter daytime pattern, β=.014, 95% CI (.006, .022) and β=-.0007 95% CI (-.001, -.0002) for the linear and quadratic slopes, respectively. Effect sizes in creatinine corrected BPA models were slightly smaller. None of the interactions between fetal sex and BPA were significant (all 95% CI's include zero).

CONCLUSIONS

These findings provide the first human evidence suggesting that BPA exposure is associated with dysregulation of HPA-axis function during pregnancy.

Maternal Whole Blood Gene Expression at 18 and 28 Weeks of Gestation Associated with Spontaneous Preterm Birth in Asymptomatic Women

The heterogeneity of spontaneous preterm birth (SPTB) requires an interdisciplinary approach to determine potential predictive risk factors of early delivery. The aim of this study was to investigate maternal whole blood gene expression profiles associated with spontaneous preterm birth (SPTB, <37 weeks) in asymptomatic pregnant women. The study population was a matched subgroup of women (51 SPTBs, 114 term delivery controls) who participated in the All Our Babies community based cohort in Calgary (n = 1878). Maternal blood at 17–23 (sampling time point 1, T₁) and 27–33 weeks of gestation (T₂) were collected. Total RNA was extracted and microarray was performed on 326 samples (165 women). Univariate analyses determined significant clinical factors and differential gene expression associated with SPTB. Thirteen genes were validated using qRT-PCR. Three multivariate logistic models were constructed to identify gene expression at T₁ (Model A), T₂ (Model B), and gene expression fold change from T₁ to T₂ (Model C) associated with SPTB. All models were adjusted for clinical factors. Model C can predict SPTB with 65% sensitivity and 88% specificity in asymptomatic women after adjusting for history of abortion and anaemia (occurring before T₂). Clinical data enhanced the sensitivity of the Models to predict SPTB. In conclusion, clinical factors and whole blood gene expression are associated with SPTB in asymptomatic women. An effective screening tool for SPTB during pregnancy would enable targeted preventive approaches and personalised antenatal care.

Perinatal nutrition in maternal mental health and child development: Birth of a pregnancy cohort

BACKGROUND

Mental disorders are one of the leading contributors to the global burden of disease. The Alberta Pregnancy Outcomes and Nutrition (APrON) study was initiated in 2008 to better understand perinatal environmental impacts on maternal mental health and child development.

AIMS

This pregnancy cohort was established to investigate the relationship between the maternal environment (e.g. nutritional status), maternal mental health status, birth outcomes, and child development. The purpose of this paper is to describe the creation of this longitudinal cohort, the data collection tools and procedures, and the background characteristics of the participants.

SUBJECTS

Participants were pregnant women age 16 or older, their infants and the biological fathers.

OUTCOME MEASURES

For the women, data were collected during each trimester of pregnancy and at 3, 6, 12, 24, and 36months after the birth of their infant. Maternal measures included diet, stress, current mental and physical health, health history, and lifestyle. In addition, maternal biological samples (DNA, blood, urine, and spot breast milk samples) were banked. Paternal data included current mental and physical health, health history, lifestyle, and banked DNA samples. For infants, DNA and blood were collected as well as information on health, development and feeding behavior.

RESULTS

At the end of recruitment in 2012, the APrON cohort included 2140 women, 2172 infants, and 1417 biological fathers. Descriptive statistics of the cohort, and comparison of women who stayed in the study and those who dropped out are discussed.

CONCLUSION

Findings from the longitudinal cohort may have important implications for health policy and clinical practice.

Recruitment and retention of pregnant women into clinical research trials: an overview of challenges, facilitators, and best practices

Pregnant women are a vulnerable group who are needed in clinical research studies to advance prevention and treatment options for this population. Yet, pregnant women remain underrepresented in clinical research. Through the lens of the socioecological model, we highlight reported barriers and facilitators to recruitment and retention of pregnant women in studies that sought their participation. We trace historical, policy-based reasons for the exclusion of pregnant women in clinical studies to present-day rationale for inclusion of this group. The findings highlight why it has been difficult to recruit and retain this population over time. A body of literature suggests that integrative sampling and recruitment methods that leverage the influence and reach of prenatal providers will overcome recruitment challenges. We argue that these strategies, in combination with building strong engagement with existing community-based organizations, will enable teams to more effectively promote and retain pregnant women in future longitudinal cohort studies.