Telehealth in a Pelvic Floor Physical Therapy Clinic: A Retrospective Cohort Study

IMPORTANCE

Telehealth offers advantages to patients with pelvic floor disorders because they face unique barriers to care; however, attendance of telehealth appointments is unknown.

OBJECTIVE

The objective of this study was to examine the attendance of telehealth appointments in urogynecology patients receiving pelvic floor physical therapy as compared with in-person visits before and during the COVID-19 pandemic.

STUDY DESIGN

We retrospectively collected electronic medical record data from patients engaging in pelvic floor physical therapy from 2019, and pre- and post-COVID-19 in 2020. Information included appointment type, attendance, age, primary diagnoses, insurance status, and zip code. Cohort differences were examined using the χ2 test and analyses of variance.

RESULTS

Our sample included 359 individuals scheduled for in-person visits in 2019, 57 for telehealth visits in 2020, and 283 for in-person visits in 2020. Patients scheduled for telehealth appointments were younger (39 ± 13 years) than patients in 2019 (45 ± 14 years) or 2020 (42 ± 14 years) in-person cohorts (χ2 (2, 696) = 6.8, P < 0.001). Patients attended telehealth appointments at higher rates (73.7%) than in-person visits in 2019 (56.8%) and 2020 (45.6%; χ2 (2, 699) = 26.2, P < 0.001). Attendance did not differ across primary diagnoses. Proximity based on zip code was not associated with attendance.

CONCLUSIONS

Pelvic floor physical therapy attendance rates were highest for patients with telehealth visits as compared with in-person visits. Our findings encourage health care providers to continue or begin to offer telehealth visits for pelvic floor physical therapy for the urogynecology patient population.

Survey of stigma across healthcare workers in an urban, academic medical center regarding perinatal patients using opioids

BACKGROUND AND OBJECTIVES

To examine healthcare workers' attitudes towards pregnant woman using opioids across provider type, specialty, and years of service.

METHODS

Cross-sectional, anonymous survey of healthcare workers at an urban, academic medical center regarding attitudes towards pregnant women using opioids.

RESULTS

One hundred and nineteen surveys were completed. Nurses were less likely to feel sympathetic towards pregnant women that use opioids (p = .016).

DISCUSSION AND CONCLUSIONS

Differences in attitudes towards pregnant women using opioids were found between clinicians and nurses.

SCIENTIFIC SIGNIFICANCE

Training and experience may contribute to attitude differences towards pregnant women using opioids.

Quantifying the risk of ectopic pregnancy with a transient diagnosis of pregnancy of unknown location

OBJECTIVE

To quantify the risk of ectopic pregnancy among a transient diagnosis of pregnancy of unknown location (PUL).

METHODS

Retrospective cohort study between August 2016 and November 2020. The final cohort included 244 patients with 255 PULs who presented with vaginal bleeding and/or abdominal pain, positive serum quantitative β-human chorionic gonadotropin, and negative transvaginal ultrasound, with a subsequent definitive diagnosis. Two-way analysis of variance was used with significance set at P < 0.050. Bonferroni-corrected significance values were used in post hoc analysis. Multinominal logistic regression was used to predict adjusted risk for pregnancy outcome.

RESULTS

Definitive diagnosis consisted of 101 (39%) intrauterine pregnancies, 33 (13%) ectopic pregnancies, and 121 (48%) resolved PULs or resolved/treated persisting PULs. A total 68% of the PULs subsequently became nonviable. Vaginal bleeding was associated with increased risk of nonuterine pregnancies.

CONCLUSION

A total of 13% of PULs were subsequently diagnosed as ectopic pregnancies, which is higher than the 2% to 3% risk of an ectopic pregnancy in the general reproductive population. A total of 68% of PULs were subsequently nonviable, which is higher than the 31% early pregnancy loss rate in the general reproductive population. This study quantitatively confirms that a transient diagnosis of a PUL increases the odds for ectopic pregnancy and early pregnancy loss.

Racial bias in cesarean decision-making

BACKGROUND

Category II fetal heart tracing noted during continuous external fetal monitoring is a frequent indication for cesarean delivery in the United States despite its somewhat subjective interpretation. Black patients have higher rates of cesarean delivery and higher rates for this indication. Racial bias in clinical decision-making has been demonstrated throughout medicine, including in obstetrics.

OBJECTIVE

We sought to examine if racial bias affects providers' decisions about cesarean delivery for an indication of category II fetal heart tracings.

STUDY DESIGN

We constructed an online survey study consisting of 2 clinical scenarios of patients in labor with category II tracings. Patient race was randomized to Black and White; the vignettes were otherwise identical. Participants had the option to continue with labor or to proceed with a cesarean delivery at 3 decision points in each scenario. Participants reported their own demographics anonymously. This survey was distributed to obstetrical providers via email, listserv, and social media. Data were analyzed using chi-square tests at each decision point in the overall sample and in subgroup analyses by various participant demographics.

RESULTS

A total of 726 participants contributed to the study. We did not find significant racial bias in cesarean delivery decision-making overall. However, in a scenario of a patient with a previous cesarean delivery, Fisher's exact tests showed that providers <40 years old (n=322; P=.01) and those with <10 years of experience (n=239; P=.050) opted for a cesarean delivery for Black patients more frequently than for White patients at the first decision point. As labor progressed in this scenario, the rates of cesarean delivery equalized across patient race.

CONCLUSION

Younger providers and those with fewer years of clinical experience demonstrated racial bias in cesarean delivery decision-making at the first decision point early in labor. Providers did not show racial bias as labor progressed, nor in the scenario with a patient without a previous cesarean delivery. This bias may be the consequence of provider training with the Maternal-Fetal Medicine Unit Network Vaginal Birth After Cesarean Calculator, developed in 2007, and widely used to estimate the probability of successful vaginal birth after a cesarean delivery. This calculator used race as a predictive factor until it was removed in June 2021. Future studies should investigate if this bias persists following this change, while also focusing on interventions to address these findings.

Associations between provider-assigned Apgar score and neonatal race

BACKGROUND

For decades, the Apgar scoring system has been used to evaluate neonatal status and determine need for resuscitation or escalation in care, such as admission to a neonatal intensive care unit. However, the variation and accuracy of provider-assigned Apgar scores across neonatal racial groups have yet to be evaluated.

OBJECTIVE

This study aimed to investigate how provider-assigned Apgar scores vary by neonatal race independently of clinical factors and umbilical cord gas values.

STUDY DESIGN

We conducted a retrospective cohort study at an urban academic medical center. All live births at ≥23 weeks and 0 days of gestation from January 1, 2019 through December 31, 2019 with complete data available were included. Data were queried from the electronic medical record and included race, ethnicity, gestational age of neonate, umbilical cord gas values (umbilical artery pH and base deficit), admission to the neonatal intensive care unit, and presence of maternal-fetal complications. Primary outcome measures were neonates' Apgar scores at 1 and 5 minutes. Color Apgar score and admission to the neonatal intensive care unit served as secondary outcome measures. We performed 3 partially proportional ordinal regression models controlling for an increasing number of covariates, with Model 1, the baseline model, adjusted for gestational age, Model 2 additionally adjusted for umbilical cord gases, and Model 3 additionally adjusted for maternal medical conditions and pregnancy complications.

RESULTS

A total of 977 neonates met selection criteria; 553 (56.6%) were Black. Providers assigned Black neonates significantly lower Apgar scores at 1 minute (odds ratio, 0.63; 95% confidence interval, 0.49-0.80) and 5 minutes (odds ratio, 0.64; 95% confidence interval, 0.47-0.87), when controlling for umbilical artery gases, gestational age, and maternal-fetal complications. This difference seemed related to significantly lower assigned color Apgar scores at 1 minute when controlling for all the above factors (odds ratio, 0.52; 95% confidence interval, 0.39-0.68). Providers admitted full-term Black neonates to the neonatal intensive care unit at higher rates than non-Black neonates when controlling for all factors (odds ratio, 1.29; 95% confidence interval, 0.94-1.77). Black neonates did not have more abnormal cord gas values (mean umbilical artery pH of 7.259 for Black vs 7.256 for non-Black neonates), which would have supported their admission to the neonatal intensive care unit.

CONCLUSION

Providers applied inaccurate Apgar scores to Black neonates given that the umbilical cord gases were not in agreement with lower Apgar scores. These inaccuracies may be a factor in unnecessary admissions to neonatal intensive care units, and suggest that colorism and racial biases exist among healthcare providers.

Obesity and the increasing odds of cesarean delivery

BACKGROUND

Knowledge of the associations between obesity and cesarean delivery (CD) is limited by previous research that does not separate the highest BMI classes.

METHODS

We identified 25,604 pregnancies in retrospective electronic medical records at an inner-city academic hospital between 2000 and 2015. We examined the association between BMI at pre-pregnancy and delivery, as well as gestational weight gain (GWG), and rates of CD, gestational diabetes mellitus (GD), and pregnancy-induced hypertension (PIH) using logistic regression and chi-square.

RESULTS

CD increased with each increase in delivery BMI class [X² (7, N = 25,604) =151.40, p < .0001]. GD and PIH also significantly increased across each BMI class. Each increasing BMI class predicted 1.21 times greater odds of CD even after adjusting for maternal age, year of birth, GD, and PIH [OR = 1.21 (95% CI, 1.07-1.37)]. As compared with the IOM recommended GWG, less weight gain offered mitigation of CD and GD, though less than the recommended GWG for women who were obese pre-pregnancy also increased odds of preterm birth, low birth weight, and stillbirth.

CONCLUSIONS

Increasing BMI is associated with increasing rates of adverse obstetric outcomes. There exists a "dose-dependent" effect of BMI on CD and limiting GWG may be associated with mitigated risk for this outcome, but increased risk for offspring adverse birth outcomes.

Parenting intentions in transgender and gender-nonconforming adults

OBJECTIVE

To assess parenting intentions, knowledge and attitudes regarding fertility preservation, and barriers to achieving parenthood in an adult transgender population.

METHODS

This was a multi-center online cross-sectional study conducted at three university-affiliated and 15 community-affiliated clinics within a major US city. Inclusion criteria included being aged 18 years and older and self-identification as transgender, gender non-conforming or non-binary. Eighty respondents completed a 36-question survey regarding their transition and plans to achieve parenthood. We compared demographic characteristics to plan for transition using Chi-Square analysis. We compared options to achieve parenthood to plans for transition using ANOVA, Spearman's rho correlation coefficient, and a Kruskal Wallis H test.

RESULTS

The mean desire to become a parent was 59.9 on a scale of 1-100. There was no significant association between plan for gonadectomy and reduced preference for the use of autologous gametes for parenting [H(2) = 1.309, P = 0.520]. The desire to have children was correlated with an increasing willingness to pause cross-sex hormones (r_s  = 0.40, P < 0.01). Cost was identified as the largest barrier to fertility preservation (54.1%).

CONCLUSION

The majority of transgender adults surveyed desire parenthood and this could be correlated with plan for transition including willingness to suspend cross-sex hormones.

Associations between inpatient psychiatric admissions during pregnancy and adverse obstetrical and birth outcomes

BACKGROUND

Previous research supports an association between psychiatric diagnoses and adverse obstetrical and neonatal outcomes including low birthweight, preterm birth, and preeclampsia. Women who are admitted for inpatient psychiatric care are regarded as having more acute illnesses than those who are able to be managed as outpatients. Previous research has not yet investigated how the severity of psychiatric illness, as indicated by type of antenatal psychiatric care received, is associated with adverse obstetrical outcomes.

OBJECTIVE

This study examines whether the rates of adverse birth and obstetrical outcomes vary with the type of antenatal psychiatric care received when psychiatric care is indicated.

STUDY DESIGN

Using a retrospective, observational design, information about women who gave birth between January 1, 2006, and December 31, 2016 was captured from electronic medical records. Women were grouped as follows: (1) those who received antepartum inpatient psychiatric treatment (n=148), (2) those with documented psychiatric history without antepartum inpatient treatment (n=301), and (3) those with no documented psychiatric history or antepartum treatment (n=301). Linear and logistic regression predicted the odds of birth and obstetrical outcomes including gestational age at birth, birthweight, mode of delivery, time to delivery, preterm premature rupture of membranes, meconium-stained amniotic fluid, and 5-minute Apgar score. Measured covariates included maternal age, race, parity, body mass index, maternal medical comorbidities, smoking tobacco, gestational age at first prenatal visit, and psychotropic medication use during pregnancy.

RESULTS

Women with a psychiatric history, despite receiving any type of antepartum psychiatric care, had higher rates of adverse outcomes than women without documented psychiatric history. However, women who received antepartum inpatient psychiatric care had longer gestational lengths (38.05±3.0 vs 37.19±4.23 weeks [P<.05]) and gave birth to heavier babies (3047.84±591.99 vs 2906.48±851.85 g [P<.01]) than women with a psychiatric history who did not receive antepartum inpatient care even when adjusting for measured covariates.

CONCLUSION

Receiving antepartum inpatient psychiatric care may promote positive birth outcomes for women with acutely severe psychiatric conditions.

The intergenerational transmission of suicidal behavior: an offspring of siblings study

We examined the extent to which genetic factors shared across generations, measured covariates, and environmental factors associated with parental suicidal behavior (suicide attempt or suicide) account for the association between parental and offspring suicidal behavior. We used a Swedish cohort of 2,762,883 offspring born 1973-2001. We conducted two sets of analyses with offspring of half- and full-siblings: (1) quantitative behavior genetic models analyzing maternal suicidal behavior and (2) fixed-effects Cox proportional hazard models analyzing maternal and paternal suicidal behavior. The analyses also adjusted for numerous measured covariates (e.g., parental severe mental illness). Quantitative behavior genetic analyses found that 29.2% (95% confidence interval [CI], 5.29, 53.12%) of the intergenerational association was due to environmental factors associated with exposure to maternal suicidal behavior, with the remainder due to genetic factors. Statistical adjustment for parental behavioral health problems partially attenuated the environmental association; however, the results were no longer statistically significant. Cox hazard models similarly found that offspring were at a 2.74-fold increased risk [95% CI, 2.67, 2.83]) of suicidal behavior if their mothers attempted/died by suicide. After adjustment for familial factors and measured covariates, associations attenuated but remained elevated for offspring of discordant half-siblings (HR, 1.57 [95% CI, 1.45, 1.71]) and full-siblings (HR, 1.62 [95% CI, 1.57, 1.67]). Cox hazard models demonstrated a similar pattern between paternal and offspring suicidal behavior. This study found that the intergenerational transmission of suicidal behavior is largely due to shared genetic factors, as well as factors associated with parental behavioral health problems and environmental factors associated with parental suicidal behavior.

Risk factors and child outcomes associated with short and long interpregnancy intervals

Previous research assessing consequences of interpregnancy intervals (IPIs) on child development is mixed. Utilizing a population-based US sample (n=5,339), we first estimated the associations between background characteristics (e.g., sociodemographic and maternal characteristics) and short (≤ 1 year) and long (> 3 years) IPI. Then, we estimated associations between IPI and birth outcomes, infant temperament, cognitive ability, and externalizing symptoms. Several background characteristics, such as maternal age at childbearing and previous pregnancy loss, were associated with IPI, indicating research on the putative effects of IPI must account for background characteristics. After covariate adjustment, short IPI was associated with poorer fetal growth and long IPI was associated with lower infant activity level; however, associations between short and long IPI and the other outcomes were neither large nor statistically significant. These findings indicate that rather than intervening to modify IPI, at-risk families may benefit from interventions aimed at other modifiable risk factors.

Socioemotional dispositions of children and adolescents predict general and specific second-order factors of psychopathology in early adulthood: A 12-year prospective study

We previously hypothesized that the ubiquitous, but patterned correlations among all dimensions of psychopathology reflect a hierarchy of progressively more nonspecific causal influences, with a general factor of psychopathology-also dubbed the p factor-reflecting the most transdiagnostic causal influences. We further hypothesized that the general factor is a manifestation of individual differences in 1 or more trait-like dispositions, particularly negative emotionality, that are nonspecifically associated with risk for essentially every dimension of psychopathology. We tested the hypothesis that this and other dispositions measured in childhood/adolescence significantly predict general and specific second-order dimensions of psychopathology in early adulthood. The latent general factor of psychopathology itself was correlated over time from 10-17 to 23-31 years of age even though it was defined by different informants and different dimensions of symptoms. Using a measure of dispositions that minimizes item contamination with psychopathology symptoms, parent-rated negative emotionality in childhood and adolescence predicted the general factor of psychopathology based on self-reported symptoms in early adulthood, whereas parent-rated daring predicted the specific adult externalizing psychopathology factor after correction for multiple tests. In addition, youth-rated negative emotionality and daring predicted specific adult externalizing psychopathology. These results over a span of 12 years suggests that the general factor is relatively stable over time and that associations of dispositional traits with second-order dimensions of psychopathology are enduring, sometimes across informants. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Outcome-dependent associations between short interpregnancy interval and offspring psychological and educational problems: a population-based quasi-experimental study

Background

Causal interpretation of associations between short interpregnancy interval (the duration from the preceeding birth to the conception of the next-born index child) and the offspring's psychological and educational problems may be influenced by a failure to account for unmeasured confounding.

Methods

Using population-based Swedish data from 1973-2009, we estimated the association between interpregnancy interval and outcomes [autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), severe mental illness, suicide attempt, criminality, substance-use problem and failing grades] while controlling for measured covariates. We then used cousin comparisons, post-birth intervals (the interval between the second- and third-born siblings to predict second-born outcomes) and sibling comparisons to assess the influence of unmeasured confounding. We included an exploratory analysis of long interpregnancy interval.

Results

Interpregnancy intervals of 0-5 and 6-11 months were associated with higher odds of outcomes in cohort analyses. Magnitudes of association were attenuated following adjustment for measured covariates. Associations were eliminated for ADHD, severe mental illness and failing grades, but maintained magnitude for ASD, suicide attempt, criminality and substance-use problem in cousin comparisons. Post-birth interpregnancy interval and sibling comparisons suggested some familial confounding. Associations did not persist across models of long interpregnancy interval.

Conclusions

Attenuation of the association in cousin comparisons and comparable post-birth interval associations suggests that familial genetic or environmental confounding accounts for a majority of the association for ADHD, severe mental illness and failing grades. Modest associations appear independently of covariates for ASD, suicide attempt, criminality and substance-use problem. Post-birth analyses and sibling comparisons, however, show some confounding in these associations.

Maternal infection requiring hospitalization during pregnancy and attention-deficit hyperactivity disorder in offspring: a quasi-experimental family-based study

BACKGROUND

Maternal infection during pregnancy (IDP) has been associated with increased risk of attention-deficit/hyperactivity disorder (ADHD) in offspring. However, infection is associated with social adversity, poor living conditions and other background familial factors. As such, there is a need to rule out whether the observed association between maternal IDP and ADHD might be attributed to such confounding.

METHODS

This nationwide population-based cohort study using a family-based, quasi-experimental design included 1,066,956 individuals born in Sweden between 1992 and 2002. Data on maternal IDP (bacterial or viral) requiring hospitalization and ADHD diagnosis in offspring were gathered from Swedish National Registers, with individuals followed up through the end of 2009. Ordinary and stratified Cox regression models were used for estimation of hazard ratios (HRs) and several measured covariates were considered. Cousin- and sibling-comparisons accounted for unmeasured genetic and environmental factors shared by cousins and siblings.

RESULTS

In the entire population, maternal IDP was associated with ADHD in offspring (HR = 2.31, 95% CI = 2.04-2.61). This association was attenuated when accounting for measured covariates (HR = 1.86, 95% CI = 1.65-2.10). The association was further attenuated when adjusting for unmeasured factors shared between cousins (HR = 1.52, 95% CI = 1.12-2.07). Finally, the association was fully attenuated in sibling comparisons (HR = 1.03, 95% CI = 0.76-1.41).

CONCLUSIONS

This study suggests that the association between maternal IDP and offspring ADHD is largely due to unmeasured familial confounding. Our results underscore the importance of adjusting for unobserved familial risk factors when exploring risk factors for ADHD.

Extending the developmental origins of disease model: Impact of preconception stress exposure on offspring neurodevelopment

The concept of the developmental origins of health and disease via prenatal programming has informed many etiologic models of health and development. Extensive experimental research in non-human animal models has revealed the impact of in utero exposure to stress on fetal development and neurodevelopment later in life. Stress exposure, however, is unlikely to occur de novo following conception, and pregnancy health is not independent of the health of the system prior to conception. For these reasons, the preconception period is emerging as an important new focus for research on adverse birth outcomes and offspring neurodevelopment. In this review, we summarize the existing evidence for the role of preconception stress exposure on pregnancy health and offspring neurodevelopment across species and discuss the implications of this model for addressing health disparities in obstetrics and offspring outcomes.

Prospective test of the developmental propensity model of antisocial behavior: from childhood and adolescence into early adulthood

BACKGROUND

The developmental propensity model of antisocial behavior posits that several dispositional characteristics of children transact with the environment to influence the likelihood of learning antisocial behavior across development. Specifically, greater dispositional negative emotionality, greater daring, and lower prosociality-operationally, the inverse of callousness- and lower cognitive abilities are each predicted to increase risk for developing antisocial behavior.

METHODS

Prospective tests of key predictions derived from the model were conducted in a high-risk sample of 499 twins who were assessed on dispositions at 10-17 years of age and assessed for antisocial personality disorder (APD) symptoms at 22-31 years of age. Predictions were tested separately for parent and youth informants on the dispositions using multiple regressions that adjusted for oversampling, nonresponse, and clustering within twin pairs, controlling demographic factors and time since the first assessment.

RESULTS

Consistent with predictions, greater numbers of APD symptoms in adulthood were independently predicted over a 10-15 year span by higher youth ratings on negative emotionality and daring and lower youth ratings on prosociality, and by parent ratings of greater negative emotionality and lower prosociality. A measure of working memory did not predict APD symptoms.

CONCLUSIONS

These findings support future research on the role of these dispositions in the development of antisocial behavior.

Measuring the hierarchical general factor model of psychopathology in young adults

There is evidence that models of psychopathology specifying a general factor and specific second-order factors fit better than competing structural models. Nonetheless, additional tests are needed to examine the generality and boundaries of the general factor model. In a selected second wave of a cohort study, first-order dimensions of psychopathology symptoms in 499 23- to 31-year-old twins were analyzed. Using confirmatory factor analysis, a bifactor model specifying a general factor and specific internalizing and externalizing factors fit better than competing models. Factor loadings in this model were sex invariant despite greater variances in the specific internalizing factor among females and greater variances in the general and specific externalizing factors among males. The bifactor structure was robust to the exclusion of any single first-order dimension of psychopathology. Furthermore, the results were essentially unchanged when all overlapping symptoms that define multiple disorders were excluded from symptom dimensions. Furthermore, the best-fitting bifactor model also emerged in exploratory structural equation modeling with freely estimated cross-loadings. The general factor of psychopathology was robust across variations in measurement and analysis.

The association between childhood relocations and subsequent risk of suicide attempt, psychiatric problems, and low academic achievement

BACKGROUND

Given the frequency with which families change residences, the effects of childhood relocations have gained increasing research attention. Many researchers have demonstrated that childhood relocations are associated with a variety of adverse outcomes. However, drawing strong causal claims remains problematic due to uncontrolled confounding factors.

METHOD

We utilized longitudinal, population-based Swedish registers to generate a nationally representative sample of offspring born 1983-1997 (n = 1 510 463). Using Cox regression and logistic regression, we examined the risk for numerous adverse outcomes after childhood relocation while controlling for measured covariates. To account for unmeasured genetic and environmental confounds, we also compared differentially exposed cousins and siblings.

RESULTS

In the cohort baseline model, each annual relocation was associated with risk for the adverse outcomes, including suicide attempt [hazard ratio (HR) 1.19, 95% confidence interval (CI) 1.19-1.20]. However, when accounting for offspring and parental covariates (HR 1.08, 95% CI 1.07-1.09), as well as genetic and environmental confounds shared by cousins (HR 1.07, 95% CI 1.05-1.09) and siblings (HR 1.00, 95% CI 0.97-1.04), the risk for suicide attempt attenuated. We found a commensurate pattern of results for severe mental illness, substance abuse, criminal convictions, and low academic achievement.

CONCLUSIONS

Previous research may have overemphasized the independent association between relocations and later adverse outcomes. The results suggest that the association between childhood relocations and suicide attempt, psychiatric problems, and low academic achievement is partially explained by genetic and environmental confounds correlated with relocations. This study demonstrates the importance of using family-based, quasi-experimental designs to test plausible alternate hypotheses when examining causality.

Translational Epidemiologic Approaches to Understanding the Consequences of Early-Life Exposures

Prominent developmental theories posit a causal link between early-life exposures and later functioning. Yet, observed associations with early exposures may not reflect causal effects because of genetic and environmental confounding. The current manuscript describes how a systematic series of epidemiologic analyses that combine several genetically-informative designs and statistical approaches can help distinguish between competing theories. In particular, the manuscript details how combining the use of measured covariates with sibling-comparisons, cousin-comparisons, and additional designs can help elucidate the sources of covariation between early-life exposures and later outcomes, including the roles of (a) factors that are not shared in families, including a potential causal effect of the exposure; (b) carryover effects from the exposure of one child to the next; and (c) familial confounding. We also describe key assumptions and how they can be critically evaluated. Furthermore, we outline how subsequent analyses, including effect decomposition with respect to measured, plausible mediators, and quantitative genetic models can help further specify the underlying processes that account for the associations between early-life exposures and offspring outcomes.

Preconception Maternal Bereavement and Infant and Childhood Mortality: A Danish Population-Based Study

OBJECTIVES

Preconception maternal bereavement may be associated with an increased risk for infant mortality, although these previously reported findings have not been replicated. We sought to examine if the association could be replicated and explore if risk extended into childhood.

METHODS

Using a Danish population-based sample of offspring born 1979 to 2009 (N = 1,865,454), we analyzed neonatal (0-28 days), postneonatal infant (29-364 days), and early childhood (1-5 years) mortality after maternal bereavement in the preconception (6-0 months before pregnancy) and prenatal (between conception and birth) periods. Maternal bereavement was defined as death of a first-degree relative of the mother. Analyses were conducted using logistic and log-linear Poisson regressions that were adjusted for offspring, mother, and father sociodemographic and health factors.

RESULTS

We identified 6541 (0.004%) neonates, 3538 (0.002%) postneonates, and 2132 (0.001%) children between the ages of 1 and 5 years who died. After adjusting for covariates, bereavement during the preconception period was associated with increased odds of neonatal (adjusted odds ratio = 1.87, 95% confidence interval = 1.53-2.30) and postneonatal infant mortality (adjusted odds ratio = 1.52, 95% confidence interval = 1.15-2.02). Associations were timing specific (6 months before pregnancy only) and consistent across sensitivity analyses. Bereavement during the prenatal period was not consistently associated with increased risk of offspring mortality; however, this may reflect relatively low statistical power.

CONCLUSIONS

Results support and extend previous findings linking bereavement during the preconception period with increased odds of early offspring mortality. The period immediately before pregnancy may be a sensitive period with potential etiological implications and ramifications for offspring mortality.

Fetal growth and psychiatric and socioeconomic problems: population-based sibling comparison

BACKGROUND

It is unclear whether associations between fetal growth and psychiatric and socioeconomic problems are consistent with causal mechanisms.

AIMS

To estimate the extent to which associations are a result of unmeasured confounding factors using a sibling-comparison approach.

METHOD

We predicted outcomes from continuously measured birth weight in a Swedish population cohort (n = 3 291 773), while controlling for measured and unmeasured confounding.

RESULTS

In the population, lower birth weight (⩽ 2500 g) increased the risk of all outcomes. Sibling-comparison models indicated that lower birth weight independently predicted increased risk for autism spectrum disorder (hazard ratio for low birth weight = 2.44, 95% CI 1.99-2.97) and attention-deficit hyperactivity disorder. Although attenuated, associations remained for psychotic or bipolar disorder and educational problems. Associations with suicide attempt, substance use problems and social welfare receipt, however, were fully attenuated in sibling comparisons.

CONCLUSIONS

Results suggest that fetal growth, and factors that influence it, contribute to psychiatric and socioeconomic problems.

Testing the Developmental Origins of Health and Disease Hypothesis for Psychopathology Using Family-Based Quasi-Experimental Designs

The Developmental Origin of Health and Disease (DOHaD) hypothesis is a broad theoretical framework that emphasizes how early risk factors have a causal influence on psychopathology. Researchers have raised concerns about the causal interpretation of statistical associations between early risk factors and later psychopathology because most existing studies have been unable to rule out the possibility of environmental and genetic confounding. In this paper we illustrate how family-based quasi-experimental designs can test the DOHaD hypothesis by ruling out alternative hypotheses. We review the logic underlying sibling-comparison, co-twin control, offspring of siblings/twins, adoption, and in vitro fertilization designs. We then present results from studies using these designs focused on broad indices of fetal development (low birth weight and gestational age) and a particular teratogen, smoking during pregnancy. The results provide mixed support for the DOHaD hypothesis for psychopathology, illustrating the critical need to use design features that rule out unmeasured confounding.

Birth weight, physical morbidity, and mortality: a population-based sibling-comparison study

Associations between low birth weight (≤2,500 g) and increased risk of mortality and morbidity provided the foundation for the "developmental origins of health and disease" hypothesis. Previous between-family studies could not control for unmeasured confounders. Therefore, we compared differentially exposed siblings to estimate the extent to which the associations were due to uncontrolled factors. Our population cohort included 3,291,773 persons born in Sweden from 1973 to 2008. Analyses controlled for gestational age, among other covariates, and considered birth weight as both an ordinal and a continuous variable. Outcomes included mortality after 1 year, cardiac-related death, hypertension, ischemic heart disease, pulmonary circulation problems, stroke, and type 2 diabetes mellitus. We fitted fixed-effects models to compare siblings and conducted sensitivity analyses to test alternative explanations. Across the population, the lower the birth weight, the greater the risk of mortality (e.g., cardiac-related death (low birth weight hazard ratio = 2.69, 95% confidence interval: 2.05, 3.53)) and morbidity (e.g., type 2 diabetes mellitus (low birth weight hazard ratio = 1.79, 95% confidence interval: 1.50, 2.14)) outcomes in comparison with normal birth weight. All associations were independent of shared familial confounders and measured covariates. Results emphasize the importance of birth weight as a risk factor for subsequent mortality and morbidity.

Offspring psychopathology following preconception, prenatal and postnatal maternal bereavement stress

BACKGROUND

Preconception, prenatal and postnatal maternal stress is associated with increased offspring psychopathology, but findings are inconsistent and need replication. We estimated associations between maternal bereavement stress and offspring autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), bipolar disorder, schizophrenia, suicide attempt and completed suicide.

METHOD

Using Swedish registers, we conducted the largest population-based study to date examining associations between stress exposure in 738,144 offspring born 1992-2000 for childhood outcomes and 2,155,221 offspring born 1973-1997 for adult outcomes with follow-up to 2009. Maternal stress was defined as death of a first-degree relative during (a) the 6 months before conception, (b) pregnancy or (c) the first two postnatal years. Cox proportional survival analyses were used to obtain hazard ratios (HRs) in unadjusted and adjusted analyses.

RESULTS

Marginal increased risk of bipolar disorder and schizophrenia following preconception bereavement stress was not significant. Third-trimester prenatal stress increased the risk of ASD [adjusted HR (aHR) 1.58, 95% confidence interval (CI) 1.15-2.17] and ADHD (aHR 1.31, 95% CI 1.04-1.66). First postnatal year stress increased the risk of offspring suicide attempt (aHR 1.13, 95% CI 1.02-1.25) and completed suicide (aHR 1.51, 95% CI 1.08-2.11). Bereavement stress during the second postnatal year increased the risk of ASD (aHR 1.30, 95% CI 1.09-1.55).

CONCLUSIONS

Further research is needed regarding associations between preconception stress and psychopathological outcomes. Prenatal bereavement stress increases the risk of offspring ASD and ADHD. Postnatal bereavement stress moderately increases the risk of offspring suicide attempt, completed suicide and ASD. Smaller previous studies may have overestimated associations between early stress and psychopathological outcomes.

Preterm birth and mortality and morbidity: a population-based quasi-experimental study

IMPORTANCE

Preterm birth is associated with increased mortality and morbidity. However, previous studies have been unable to rigorously examine whether confounding factors cause these associations rather than the harmful effects of being born preterm.

OBJECTIVE

To estimate the extent to which the associations between early gestational age and offspring mortality and morbidity are the result of confounding factors by using a quasi-experimental design, the sibling-comparison approach, and by controlling for statistical covariates that varied within families.

DESIGN, SETTING, AND PARTICIPANTS

A population-based cohort study, combining Swedish registries to identify all individuals born in Sweden from 1973 to 2008 (3,300,708 offspring of 1,736,735 mothers) and link them with multiple outcomes.

MAIN OUTCOMES AND MEASURES

Offspring mortality (during infancy and throughout young adulthood) and psychiatric (psychotic or bipolar disorder, autism, attention-deficit/hyperactivity disorder, suicide attempts, substance use, and criminality), academic (failing grades and educational attainment), and social (partnering, parenthood, low income, and social welfare benefits) outcomes through 2009.

RESULTS

In the population, there was a dose-response relationship between early gestation and the outcome measures. For example, extreme preterm birth (23-27 weeks of gestation) was associated with infant mortality (odds ratio, 288.1; 95% CI, 271.7-305.5), autism (hazard ratio [HR], 3.2; 95% CI, 2.6-4.0), low educational attainment (HR, 1.7; 1.5-2.0), and social welfare benefits (HR, 1.3; 1.2-1.5) compared with offspring born at term. The associations between early gestation and mortality and psychiatric morbidity generally were robust when comparing differentially exposed siblings and controlling for statistical covariates, whereas the associations with academic and some social problems were greatly or completely attenuated in the fixed-effects models.

CONCLUSIONS AND RELEVANCE

The mechanisms responsible for the associations between preterm birth and mortality and morbidity are outcome-specific. Associations between preterm birth and mortality and psychiatric morbidity are largely independent of shared familial confounds and measured covariates, consistent with a causal inference. However, some associations, particularly predicting suicide attempt, educational attainment, and social welfare benefits, are the result of confounding factors. The findings emphasize the importance of both reducing preterm birth and providing wraparound services to all siblings in families with an offspring born preterm.

Maternal stress and infant mortality: the importance of the preconception period

Although preconception and prenatal maternal stress are associated with adverse outcomes in birth and childhood, their relation to infant mortality remains uncertain. We used logistic regression to study infant mortality risk following maternal stress within a population-based sample of infants born in Sweden between 1973 and 2008 (N = 3,055,361). Preconception (6-0 months before conception) and prenatal (between conception and birth) stress were defined as death of a first-degree relative of the mother. A total of 20,651 offspring were exposed to preconception stress, 26,731 offspring were exposed to prenatal stress, and 8,398 cases of infant mortality were identified. Preconception stress increased the risk of infant mortality independently of measured covariates, and this association was timing specific and robust across low-risk groups. Prenatal stress did not increase risk of infant mortality. These results suggest that the period immediately before conception may be a sensitive developmental period with ramifications for infant mortality risk.

Current parental depression and offspring perceived self-competence: a quasi-experimental examination

A genetically-informed, quasi-experimental design was used to examine the genetic and environmental processes underlying associations between current parental depressive symptoms and offspring perceived self-competence. Participants, drawn from a population-based Swedish sample, were 852 twin pairs and their male (52 %) and female offspring aged 15.7 ± 2.4 years. Parental depressive symptoms were measured using the Center for Epidemiological Studies Depression scale. Offspring perceived self-competence was measured using a modified Harter Perceived Competence Scale. Cousin comparisons and Children of Twins designs suggested that associations between maternal depressive symptoms and offspring perceived self-competence were due to shared genetic/environmental liability. The mechanism responsible for father-offspring associations, however, was independent of genetic factors and of extended family environmental factors, supporting a causal inference. Thus, mothers and fathers may impact offspring perceived self-competence via different mechanisms and unmeasured genetic and environmental selection factors must be considered when studying the intergenerational transmission of cognitive vulnerabilities for depression.

Timing of prenatal maternal exposure to severe life events and adverse pregnancy outcomes: a population study of 2.6 million pregnancies

OBJECTIVE

To identify the impact of timing of prenatal stress exposure on offspring risk for shortened gestational age, preterm birth (PTB), low birth weight (LBW), and small for gestational age (SGA), using a population-based sample.

METHODS

Swedish longitudinal population registries were linked to study all individuals born in Sweden from 1973 to 2004. Prenatal maternal stress exposure was defined as death of the father of the child or first-degree relative of the mother. Using linear and logistic regression, timing of stress exposure was examined across pregnancy, by month, and by novel periods created based on month of stress exposure findings.

RESULTS

A total of 2,618,777 live-born, singleton infants without congenital anomalies were included; 32,286 were exposed to prenatal maternal stress. Examining associations between stress exposure and outcome by the month revealed that risk increases midgestation, particularly after months 5 and 6. Combining months 1 to 4, 5 and 6, and 7 to 9 as potential periods of differing vulnerability, it was found that stress during period 2 (months 5 and 6) was associated with the greatest risk for shortened gestational age (-0.52 days, standard error = 0.15, p = .0006), PTB (odds ratio [OR], 1.24; 99% confidence interval [CI], 1.08-1.42), LBW (OR, 1.38; 99% CI, 1.19-1.61), and SGA (OR, 1.25; 99% CI, 1.05-1.49).

CONCLUSIONS

Risk for shortened GA, PTB, LBW, and SGA are greater post stress exposure during the 5th and/or 6th month of pregnancy. It may be beneficial to refine future analyses to these months. Possible mechanisms include alterations in the hypothalamic-pituitary-adrenal axis and associated stress-responsive molecular regulators.

Maturation of the human fetal startle response: evidence for sex-specific maturation of the human fetus

Despite the evidence for early fetal experience exerting programming influences on later neurological development and health risk, very few prospective studies of human fetal behavior have been reported. In a prospective longitudinal study, fetal nervous system maturation was serially assessed by monitoring fetal heart rate (FHR) responses to vibroacoustic stimulation (VAS) in 191 maternal/fetal dyads. Responses were not detected at 26 weeks gestational age (GA). Sex-specific, age-characteristic changes in the FHR response to VAS were observed by 31 weeks' GA. Males showed larger responses and continued to exhibit maturational changes until 37 weeks' GA, females however, presented with a mature FHR startle response by 31 weeks' GA. The results indicate that there are different rates of maturation in the male and female fetuses that may have implications for sex-specific programming influences.

Low levels of corticotropin-releasing hormone during early pregnancy are associated with precocious maturation of the human fetus

Elevation in placental corticotropin-releasing hormone (pCRH) during the last trimester of pregnancy has been associated with an increased risk for preterm delivery. Less is known about the consequences for the human fetus exposed to high levels of pCRH early in pregnancy. pCRH levels were measured in 138 pregnant women at least once at 15, 20 and 25 weeks of gestation. At 25 weeks of gestation, fetal heart rate (FHR) responses to a startling vibroacoustic stimulus (VAS) were recorded as an index of maturity. pCRH levels at 15 weeks of gestation, but at no later point, predicted FHR responses to the VAS. Fetuses exposed to the lowest concentrations of pCRH at 15 weeks of gestation exhibited a distinguishable response to the VAS, whereas fetuses exposed to higher levels of pCRH did not respond. The findings suggest that exposure to low levels of pCRH early in gestation may be optimal and associated with a response pattern indicating greater maturity.

Affective valence, stimulus attributes, and P300: color vs. black/white and normal vs. scrambled images

Pictures from the International Affective Picture System (IAPS) were selected to manipulate affective valence (unpleasant, neutral, pleasant) while keeping arousal level the same. The pictures were presented in an oddball paradigm, with a visual pattern used as the standard stimulus. Subjects pressed a button whenever a target was detected. Experiment 1 presented normal pictures in color and black/white. Control stimuli were constructed for both the color and black/white conditions by randomly rearranging 1 cm square fragments of each original picture to produce a "scrambled" image. Experiment 2 presented the same normal color pictures with large, medium, and small scrambled condition (2, 1, and 0.5 cm squares). The P300 event-related brain potential demonstrated larger amplitudes over frontal areas for positive compared to negative or neutral images for normal color pictures in both experiments. Attenuated and nonsignificant valence effects were obtained for black/white images. Scrambled stimuli in each study yielded no valence effects but demonstrated typical P300 topography that increased from frontal to parietal areas. The findings suggest that P300 amplitude is sensitive to affective picture valence in the absence of stimulus arousal differences, and that stimulus color contributes to ERP valence effects.