Prenatal SSRI use and offspring with autism spectrum disorder or developmental delay

Autism spectrum disorders: let's talk about glucose?

Autism spectrum disorders (ASD) are characterized by disconnectivity due to disordered neuronal migration, and by neuronal mitochondrial dysfunction. Different pathways involved in neuronal migration are affected by intrauterine hyperglycemia and hyperinsulinemia, while prolonged neonatal hypoglycemia may cause mitochondrial dysfunction. Our hypothesis was that conditions leading to intrauterine hyperglycemia or neonatal hypoglycemia would influence ASD pathogenesis. In this study, we identified risk factors for ASD by searching PubMed with the MeSH terms "autism spectrum disorder" and "risk factors". We then analyzed the relationship between the risk factors and glucose abnormalities in the mother and the offspring. The relationship between glucose abnormalities and risk factors such as obesity, excessive maternal weight gain, or diabetes mellitus is evident. For risk factors such as malformations or exposure to selective serotonin reuptake inhibitors, the relationship is speculative. In rodents, for example, intrauterine hyperglycemia is associated with malformations, independent of maternal diabetes. In their turn, selective serotonin reuptake inhibitors reduce the signs of neonatal hypoglycemia. Going undetected, prolonged hypoglycemia may harm the neonatal brain. Importantly, our group demonstrated that either high-carbohydrate diets or physical inactivity the day before delivery may influence neonatal glycemia. In that study, of 158 neonates selected to be screened according to maternal lifestyle risk factors, 48 had hypoglycemia. Of note, five of them had not been identified with current screening programs. Controlled studies are needed to clarify whether maternal interventions aiming at maintaining glycemic control, together with screening programs for neonatal hypoglycemia based on maternal lifestyle risk factors and on exposure to specific prenatal medications can reduce the prevalence of ASD.

Prenatal Risk for ASD: Fetal Cortisol Exposure Predicts Child Autism-Spectrum Disorder Symptoms

The etiology of autism spectrum disorder (ASD) is multifactorial and complex and likely involves interactions among genetic, epigenetic and environmental factors. With respect to environmental influences, a growing literature implicates intrauterine experiences in the origin of this pervasive developmental disorder. In this prospective longitudinal design, we examine the hypothesis that fetal exposure to maternal cortisol may confer ASD risk. In addition, because ASD is four times more prevalent in males than females and because sexually dimorphic responses to intrauterine experiences are commonly observed, we examine whether or not any associations differ by fetal sex. Maternal plasma cortisol was measured at 15, 19, 25, 31, and 37 weeks' gestation in a sample of 84 pregnant women. ASD symptoms were assessed in their 5-year old children with the Social Communication Questionnaire (SCQ). Fetal exposure to lower levels of maternal cortisol was associated with higher levels of ASD symptoms among boys only. The observed hypocortisolemic profile exhibited by these mothers may indicate a risk factor that precedes the stress of caregiving for a child with ASD and may not be solely a consequence of the stress of caregiving as previously thought. Further, these findings confirm the value of examining prenatal hormone exposures as predictors of ASD risk and support the premise that altered prenatal steroid exposures may play a role in the etiology of ASD.

The Utility of Zebrafish as a Model for Screening Developmental Neurotoxicity

The developing central nervous system and the blood brain barrier are especially vulnerable and sensitive to different chemicals, including environmental contaminants and drugs. Developmental exposure to these compounds has been involved in several neurological disorders, such as autism spectrum disorders as well as Alzheimer's and Parkinson's diseases. Zebrafish (Danio Rerio) have emerged as powerful toxicological model systems that can speed up chemical hazard assessment and can be used to extrapolate neurotoxic effects that chemicals have on humans. Zebrafish embryos and larvae are convenient for high-throughput screening of chemicals, due to their small size, low-cost, easy husbandry, and transparency. Additionally, zebrafish are homologous to other higher order vertebrates in terms of molecular signaling processes, genetic compositions, and tissue/organ structures as well as neurodevelopment. This mini review underlines the potential of the zebrafish as complementary models for developmental neurotoxicity screening of chemicals and describes the different endpoints utilized for such screening with some studies illustrating their use.

Maternal depression and antidepressant use during pregnancy and the risk of autism spectrum disorder in offspring

Background

Results of some studies suggest that prenatal antidepressant exposure increases the risk of autism spectrum disorder (ASD) in offspring, while other studies suggest that depression independently increases the risk of having a child with ASD. Thus, confounding by indication is a concern.

Objective

The aim of this study was to estimate the risk of ASD in offspring of women who were exposed to antidepressants and/or had depression during pregnancy compared to unexposed women.

Materials and methods

We conducted a cohort study with nested sibling case–control analysis. Using the UK Clinical Practice Research Datalink (CPRD), we identified mother– baby pairs where the mother had ≥12 months of history before the delivery date and the child had ≥3 years of follow-up. Exposures during pregnancy were classified as 1) depression treated with antidepressants, 2) untreated depression, 3) other indications for antidepressant use, and 4) 4:1 match of unexposed women with no history of depression or antidepressant use. We calculated the prevalence of ASD and relative risk (RR) with 95% CI. In the sibling analysis, we compared exposure among ASD cases to that of non-ASD siblings born to the same mother. We calculated ORs and 95% CIs for women with treated and untreated depression, compared to unexposed.

Results

We identified 2,154 offspring with ASD among 194,494 mother–baby pairs. Compared to unexposed, the RR of ASD was 1.72 (95% CI 1.54–1.93) for treated depression and 1.50 (95% CI 1.28–1.75) for untreated depression, while the RR was not elevated in women who received antidepressants for other indications (RR =0.73, 95% CI 0.41–1.29). Additional analyses to assess the effects of severity of depression suggest that the risk of ASD in offspring increases with increasing severity, not with the antidepressant treatment. The results of the sibling analysis were similar to the main analysis.

Conclusion

Women with depression during pregnancy have an increased risk of having a child with ASD, regardless of antidepressant use.

Perinatal fluoxetine has enduring sexually differentiated effects on neurobehavioral outcomes related to social behaviors

Selective serotonin reuptake inhibitor medications (SSRIs) are prescribed to up to 10% of pregnant women to treat maternal mood disorders. Exposure to these medications in-utero has raised concerns about altered neurobehavioral outcomes; most recently those related to peer-to-peer social interactions and play. While clinical data show that both perinatal SSRIs (pSSRI) and maternal stress can contribute to social behavioral changes in children, minimal animal work has investigated the effects of pSSRIs in relevant models of maternal stress or the long-term implications of these effects. Therefore the aim of this work was to investigate the long-term effects of pSSRI exposure to fluoxetine on social behaviors, the hypothalamic pituitary adrenal system (HPA) and hippocampal plasticity in adult male and female rat offspring using a model of pre-gestational maternal stress. Adult Sprague-Dawley female and male rat offspring from the following four groups were utilized: 1. Control + Vehicle, 2. Control + Fluoxetine, 3. Pre-gestational Stress + Vehicle, 4. Pre-gestational Stress + Fluoxetine (n = 8-16/female/age groups, n = 8-14/male/age groups). Main findings show pSSRIs increased social investigation in adult females and increased social play (pouncing, nape attacks) in adult males. Perinatal SSRIs also had sexually differentiated effects on hippocampal neurogenesis and GR density. Pre-gestational stress had enduring effects by decreasing social investigation and hippocampal neurogenesis in adult males. Thus pSSRIs, as well as pre-gestational maternal stress, have significant long-term effects on social neurobehavioral outcomes which differ in males and females. This suggests that it would be valuable to consider fetal-sex specific treatments for maternal mental illness.

Cluster analysis profiling of behaviors in zebrafish larvae treated with antidepressants and pesticides

Antidepressants are used by a substantial number of women in their childbearing years. Treatment may continue during pregnancy, since untreated depression poses a risk to the mother and child. However, many antidepressants readily pass through the placental barrier to reach the fetus or may be ingested by the newborn via breastmilk. Little is known about the effects of antidepressants on brain development and subsequent behavior in young children. In the current study, we used zebrafish as a model system to examine the neurodevelopmental effects of three commonly prescribed antidepressants, sertraline, duloxetine and bupropion. Zebrafish were exposed to these antidepressants during development and were examined for changes in larval avoidance behavior, activity, social behaviors, and anxiety-related behaviors. The results show that antidepressants commonly affect larval swim speeds and resting, and differentially affect other behaviors depending upon the exposure period. Using cluster analysis profiling, we compared the obtained results to previous reports on behavioral defects induced by organophosphate pesticides. We found that the behavioral profiles induced by antidepressants and pesticides overlap, indicating a common mechanism of action. We conclude that developmental antidepressant exposures lead to specific behavioral changes in zebrafish larvae. At present, it is not known if antidepressants have similar effects in human development.

An experimental test of the fetal programming hypothesis: Can we reduce child ontogenetic vulnerability to psychopathology by decreasing maternal depression?

Maternal depression is one of the most common prenatal complications, and prenatal maternal depression predicts many child psychopathologies. Here, we apply the fetal programming hypothesis as an organizational framework to address the possibility that fetal exposure to maternal depressive symptoms during pregnancy affects fetal development of vulnerabilities and risk mechanisms, which enhance risk for subsequent psychopathology. We consider four candidate pathways through which maternal prenatal depression may affect the propensity of offspring to develop later psychopathology across the life span: brain development, physiological stress regulation (hypothalamic-pituitary-adrenocortical axis), negative emotionality, and cognitive (effortful) control. The majority of past research has been correlational, so potential causal conclusions have been limited. We describe an ongoing experimental test of the fetal programming influence of prenatal maternal depressive symptoms using a randomized controlled trial design. In this randomized controlled trial, interpersonal psychotherapy is compared to enhanced usual care among distressed pregnant women to evaluate whether reducing prenatal maternal depressive symptoms has a salutary impact on child ontogenetic vulnerabilities and thereby reduces offspring's risk for emergence of later psychopathology.

Prenatal Antidepressant Exposure and Child Motor Development: A Meta-analysis

CONTEXT

There is increasing use of antidepressants in pregnancy and hence children exposed in utero. Contradictory studies exist in the literature in which researchers report on the potential impact of antenatal antidepressant exposure on subsequent child motor development.

OBJECTIVE

Our objective in this systematic review and meta-analysis was to determine whether antenatal antidepressant exposure increases the risk of impaired motor development in children.

DATA SOURCES

We searched PsychINFO, Embase, Medline, PubMed, and Scopus up to July 24, 2017.

STUDY SELECTION

English-language cohort and case control studies in which researchers report primary data from a motor assessment of infants or children after any antidepressant exposure in pregnancy were included.

DATA EXTRACTION

Of the 329 studies identified, there were 160 articles screened, 24 were included in the systematic review, and 18 met inclusion criteria for the meta-analysis.

RESULTS

The total pooled results were based on random effects models and revealed a significant association between exposure to antidepressants during pregnancy and overall occurrence of poorer motor outcomes in children (effect size = 0.22; 95% confidence interval = 0.07 to 0.37) with a moderate degree of heterogeneity (I² = 56.6%).

LIMITATIONS

There was variation in the measurement both of exposure and motor development across the identified study, and few followed up to later childhood or beyond.

CONCLUSIONS

A small increased risk of poorer motor development may exist for children who are exposed to antidepressant medications during pregnancy. However, the marked methodological variation among studies and the limited control for possible confounds warrants cautious interpretation of these findings.

Memantine rescues prenatal citalopram exposure-induced striatal and social abnormalities in mice

Prenatal exposure to citalopram (CTM), an antidepressant drug, has been associated with altered behavior, including autism-like symptoms in both human and rodent offspring. However, the neurological basis underlying these abnormal behaviors is not well understood. Here, we examined behavioral, morphological, and biochemical alterations in the male and female offspring of C57BL/6 mouse mothers that had been exposed to CTM during the last trimester of gestation. We observed abnormal behavior such as anxiety, altered locomotion and disordered social interactions in 2-5 months old offspring with prenatal CTM exposure. Using Golgi-Cox staining, we found that CTM caused significantly reduced dendritic length and number of dendritic branches in striatal neurons, as well as altered subunit levels of N-methyl-d-aspartate receptors (NMDARs) and calcium/calmodulin-dependent protein kinase II (CaMKII). Memantine, a selective NMDAR antagonist, improved prenatal CTM-induced abnormal protein levels and social interaction deficits. These results highlight potential mechanisms underlying the abnormal behavior observed in children who are prenatally exposed to CTM.

Perinatal MAO Inhibition Produces Long-Lasting Impairment of Serotonin Function in Offspring

In addition to transmitter functions, many neuroamines have trophic or ontogenetic regulatory effects important to both normal and disordered brain development. In previous work (Mejia et al., 2002), we showed that pharmacologically inhibiting monoamine oxidase (MAO) activity during murine gestation increases the prevalence of behaviors thought to reflect impulsivity and aggression. The goal of the present study was to determine the extent to which this treatment influences dopamine and serotonin innervation of murine cortical and subcortical areas, as measured by regional density of dopamine (DAT) and serotonin transporters (SERT). We measured DAT and SERT densities at 3 developmental times (PND 14, 35 and 90) following inhibition of MAO A, or MAO B or both throughout murine gestation and early post-natal development. DAT binding was unaltered within the nigrostriatal pathway, but concurrent inhibition of MAO-A and MAO-B significantly and specifically reduced SERT binding by 10–25% in both the frontal cortex and raphe nuclei. Low levels of SERT binding persisted (PND 35, 90) after the termination (PND 21) of exposure to MAO inhibitors and was most marked in brain structures germane to the previously described behavioral changes. The relatively modest level of enzyme inhibition (25–40%) required to produce these effects mandates care in the use of any compound which might inhibit MAO activity during gestation.

Interactive Effects of Prenatal Antidepressant Exposure and Likely Gene Disrupting Mutations on the Severity of Autism Spectrum Disorder

To examine the interactive effects of two proposed risk factors which may contribute to symptom severity of Autism Spectrum Disorder (ASD): prenatal antidepressant exposure and likely gene-disrupting (LGD) mutations. Participants included 2748 individuals with ASD from the Simons Simplex Collection. We examined the effects of prenatal antidepressant exposure, maternal depression, presence of an LGD mutation and their interaction on ASD severity. We found a significant interactive effect between antidepressant exposure and the presence of an LGD mutation on ASD severity in the ADOS and ADI-R verbal communication domains. We consider a "two-hit" model in which one variable lays the foundation for an initial risk which is compounded by a second variable.

Association between maternal antidepressant use during pregnancy and autism spectrum disorder: an updated meta-analysis

Studies have investigated the risk of autism spectrum disorder (ASD) in children exposed in utero to antidepressant, with inconsistent results. Given the substantial public health implications on this topic, here, we presented an updated meta-analysis of the association between maternal antidepressant use during pregnancy and ASD. Cochrane Library, EMBASE, PsycINFO, and PubMed databases were systematically searched. A random effects model was used to pool the adjusted relative risk (RR) for cohort studies and the adjusted odds ratio (OR) for case-control studies as well as their corresponding 95% confidence intervals (CIs). Meta-analysis restricted to sibling studies was also conducted. Publication bias was systematically assessed. Fourteen studies were identified (eight cohort studies and six case-control studies). Pooled adjusted RR for cohort studies (n = 2,839,980) was 1.13 (0.93–1.39) showed a non-significant association; while two studies were potentially missing from the test of publication bias, filled estimates also showed a non-significant association (filled RR 0.97, 95% CI 0.79–1.19). Pooled OR was 1.51 (1.15–1.99) for case-control studies (n = 117,737) showed a significant association; two studies were potentially missing; however, the filled estimates suggested a non-significant association (filled OR 1.26, 95% CI 0.98–1.62). Analyses restricted to sibling studies also showed a non-significant association (RR 0.99, 95% CI 0.81–1.22). In summary, we did not evidence a significant association between maternal antidepressant use during pregnancy and ASD.

Understanding environmental contributions to autism: Causal concepts and the state of science

The complexity of neurodevelopment, the rapidity of early neurogenesis, and over 100 years of research identifying environmental influences on neurodevelopment serve as backdrop to understanding factors that influence risk and severity of autism spectrum disorder (ASD). This Keynote Lecture, delivered at the May 2016 annual meeting of the International Society for Autism Research, describes concepts of causation, outlines the trajectory of research on nongenetic factors beginning in the 1960s, and briefly reviews the current state of this science. Causal concepts are introduced, including root causes; pitfalls in interpreting time trends as clues to etiologic factors; susceptible time windows for exposure; and implications of a multi-factorial model of ASD. An historical background presents early research into the origins of ASD. The epidemiologic literature from the last fifteen years is briefly but critically reviewed for potential roles of, for example, air pollution, pesticides, plastics, prenatal vitamins, lifestyle and family factors, and maternal obstetric and metabolic conditions during her pregnancy. Three examples from the case-control CHildhood Autism Risks from Genes and the Environment Study are probed to illustrate methodological approaches to central challenges in observational studies: capturing environmental exposure; causal inference when a randomized controlled clinical trial is either unethical or infeasible; and the integration of genetic, epigenetic, and environmental influences on development. We conclude with reflections on future directions, including exposomics, new technologies, the microbiome, gene-by-environment interaction in the era of -omics, and epigenetics as the interface of those two. As the environment is malleable, this research advances the goal of a productive and fulfilling life for all children, teen-agers and adults. Autism Res 2018, 11: 554-586. © 2018 International Society for Autism Research, Wiley Periodicals, Inc.

LAY SUMMARY

This Keynote Lecture, delivered at the 2016 meeting of the International Society for Autism Research, discusses evidence from human epidemiologic studies of prenatal factors contributing to autism, such as pesticides, maternal nutrition and her health. There is no single cause for autism. Examples highlight the features of a high-quality epidemiology study, and what comprises a compelling case for causation. Emergent research directions hold promise for identifying potential interventions to reduce disabilities, enhance giftedness, and improve lives of those with ASD.

Selective serotonin reuptake inhibitor use in pregnant women; pharmacogenetics, drug-drug interactions and adverse effects

INTRODUCTION

Possible negative effects of selective serotonin reuptake inhibitors (SSRIs) in pregnancy relate to congenital anomalies, negative perinatal events and neurodevelopmental outcome. Many studies are confounded by the underlying maternal disease and by pharmacogenetic and pharmacokinetic differences of these drugs. Areas covered: The possible interactions of SSRIs and serotonin and norepinephrine reuptake inhibitors with other drugs and the known effects of SSRIs on congenital anomalies, perinatal and neurodevelopmental outcome. Expert opinion: SSRIs should be given with caution when combined with other drugs that are metabolized by cytochrome P450 enzymes. SSRIs apparently increase the rate of severe cardiac malformations, induce neonatal adaptation problems in up to 30% of the offspring, increase the rate of persistent pulmonary hypertension of the newborn and possibly slightly increase the rate of prematurity and low birth weight. Most neurodevelopmental follow up studies did not find significant cognitive impairments except some transient gross motor delay, slight impairment of language abilities and possibly behavioral changes. The literature on the possible association of SSRIs with autism spectrum disorder is inconsistent; if an association exists, it is apparently throughout pregnancy. The risk associated with treatment discontinuation seems to outweigh the risk of treatment, as severe maternal depression may negatively affect the child's development. If needed, treatment should continue in pregnancy with the minimal effective dose.

Antidepressant use during pregnancy and risk of autism spectrum disorder and attention deficit hyperactivity disorder: systematic review of observational studies and methodological considerations

BACKGROUND

Antidepressant exposure during pregnancy has been associated with an increased risk of autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) in several observational studies. We performed a systematic review of these studies to highlight the effect that important methodological limitations have on such analyses and to consider approaches to the conduct, reporting and interpretation of future studies.

METHODS

A review of MEDLINE and EMBASE identified case-control, cohort and sibling studies assessing the risk of ASD and ADHD with antidepressant use during pregnancy. Approaches to confounding adjustment were described. Crude and adjusted effect estimates for comparisons between antidepressant exposure during pregnancy vs. all unexposed women were first meta-analysed using a generic inverse variance method of analysis, followed by effect estimates for alternative pre-selected comparison groups.

RESULTS

A total of 15 studies measuring ASD as an outcome (involving 3,585,686 children and 40,585 cases) and seven studies measuring ADHD as an outcome (involving 2,765,723 patients and 52,313 cases) were identified. Variation in confounding adjustment existed between studies. Updated effect estimates for the association between maternal antidepressant exposure during pregnancy vs. all unexposed women remained statistically significant for ASD (adjusted random-effects risk ratio [RaRR] 1.53, 95% confidence interval [CI] 1.31-1.78). Similar significant associations were observed using pre-pregnancy maternal antidepressant exposure (RaRR 1.48, 95% CI 1.29-1.71) and paternal antidepressant exposure during pregnancy (1.29, 95% CI 1.08-1.53), but analyses restricted to using women with a history of affective disorder (1.18, 95% CI 0.91-1.52) and sibling studies (0.96, 95% CI 0.65-1.42) were not statistically significant. Corresponding associations for risk of ADHD with exposure were: RaRR 1.38, 95% CI 1.13-1.69 (during pregnancy), RaRR 1.38, 95% CI 1.14-1.69 (during pre-pregnancy), RaRR 1.71, 95% CI 1.31-2.23 (paternal exposure), RaRR 0.98, 95% CI 0.77-1.24 (women with a history of affective disorder) and RaRR 0.88, 95% CI 0.70-1.11 (sibling studies).

CONCLUSIONS

Existing observational studies measuring the risk of ASD and ADHD with antidepressant exposure are heterogeneous in their design. Classical comparisons between exposed and unexposed women during pregnancy are at high risk of residual confounding. Alternative comparisons and sibling designs may aid the interpretation of causality and their utility requires further evaluation, including understanding potential limitations of undertaking meta-analyses with such data.

Use of Antidepressants During Pregnancy?: What to Consider when Weighing Treatment with Antidepressants Against Untreated Depression

Introduction Mood disorders impact many pregnant women, particularly those who have experienced symptoms prior to conception, and there are significant barriers, including stigma and access, to seeking and receiving appropriate treatments. Antidepressants are a helpful option in treating perinatal depression, but research on risks and benefits of antidepressant use in pregnancy is difficult given lack of "gold standard" comparative trials. Methods This paper summarizes current state of knowledge on the safety of antidepressants during pregnancy by providing a summary of the literature published in the past 3 years (January 2013-October 2015). We identified 21 reviews and meta-analyses that were included in this summary report. This report is meant to provide a user-friendly, yet comprehensive guide summarizing the abundant, and in part contradicting, literature on risks and benefits of antidepressants during pregnancy, in order to assist busy primary care prescribers in educating their patients. Our goal is also to contrast the risks/benefits of untreated depression in pregnancy versus treatment with antidepressant medication in pregnancy, and in such support prescribers in their decision-making. Results The past 3 years have yielded an abundance of publications on the topic, in part, with conflicting findings adding to confusion and concern among providers, patients, and their families. Many reported studies have methodological problems limiting their impact. Data on adverse effects of medications on pregnancy and fetal outcomes have to be weighed against the impact of untreated illness and poor health habits associated with untreated illness on the same outcomes. Discussion Medical-decision making is often complex and seldom free of risks. Obviously, as providers we cannot guarantee that fetal exposure to antidepressants is totally free of risk, yet this is true for any medicine taken in pregnancy. However, to date, perinatal psychiatry has collected enough evidence to suggest that, if the clinical picture warrants it, the use of many antidepressants, especially the SSRIs, is favorable compared to exposing mother and child to untreated depressive illness.

Autism risk following antidepressant medication during pregnancy

BACKGROUND

Previous studies have examined if maternal antidepressant medication during pregnancy increase the risk of autism spectrum disorder (ASD) in the offspring, but the results have been conflicting.

METHODS

In a population-based cohort of 179 007 children born in 2006 and 2007 and followed through 2014 when aged 7 and 8, we estimated relative risks (RRs) of ASD and 95% confidence intervals (CIs) from Cox regression in children exposed to any antidepressant medication during pregnancy, and nine specific antidepressant drugs. Analyses were adjusted for potential confounders and were conducted in the full population sample, and in a clinically relevant sub-sample of mothers with at least one diagnosis of depression or anxiety during life.

RESULTS

The adjusted RR of ASD in children of mothers who used antidepressant medication during pregnancy was estimated at 1.23 (95% CI 0.96-1.57), and at 1.07 (95% CI 0.80-1.43) in women with a history of depression or anxiety. Analyses of specific antidepressants initially revealed increased RRs of offspring ASD confined to citalopram and escitalopram (RR: 1.47; 95% CI 0.92-2.35) and clomipramine (RR: 2.86; 95% CI 1.04-7.82).

CONCLUSION

Medication with antidepressants during pregnancy does not appear to be causally associated with an increased risk of ASD in the offspring. Instead, the results suggest that the association is explained by factors related to the underlying susceptibility to psychiatric disorders. Based on these findings, the risk of ASD in the offspring should not be a consideration to withhold treatment with commonly used antidepressant drugs from pregnant women.

Association of Sex With Recurrence of Autism Spectrum Disorder Among Siblings

IMPORTANCE

Autism spectrum disorder (ASD) is known to be more prevalent among males than females in the general population. Although overall risk of recurrence of ASD among siblings has been estimated to be between 6.1% and 24.7%, information on sex-specific recurrence patterns is lacking.

OBJECTIVE

To estimate high-confidence sex-specific recurrence rates of ASD among siblings.

DESIGN, SETTING, AND PARTICIPANTS

This observational study used an administrative database to measure the incidence of ASD among children in 1 583 271 families (37 507 with at least 1 diagnosis of ASD) enrolled in commercial health care insurance plans at a large US managed health care company from January 1, 2008, through February 29, 2016. Families in the study had 2 children who were observed for at least 12 months between 4 and 18 years of age.

MAIN OUTCOMES AND MEASURES

The primary measure of ASD recurrence was defined as the diagnosis of ASD in a younger sibling of an older sibling with an ASD diagnosis.

RESULTS

Among the 3 166 542 children (1 547 266 females and 1 619 174 males; mean [SD] age, 11.2 [4.7] years) in the study, the prevalence of ASD was 1.96% (95% CI, 1.94%-1.98%) among males and 0.50% (95% CI, 0.49%-0.51%) among females. When a male was associated with risk in the family, ASD was diagnosed in 4.2% (95% CI, 3.8%-4.7%) of female siblings and 12.9% (95% CI, 12.2%-13.6%) of male siblings. When a female was associated with risk in the family, ASD was diagnosed in 7.6% (95% CI, 6.5%-8.9%) of female siblings and 16.7% (95% CI, 15.2%-18.4%) of male siblings.

CONCLUSIONS AND RELEVANCE

These findings are in agreement with the higher rates of ASD observed among males than among females in the general population. Our study provides more specific guidance for the screening and counseling of families and may help inform future investigations into the environmental and genetic factors that confer risk of ASD.

Association of Antidepressant Medication Use During Pregnancy With Intellectual Disability in Offspring

IMPORTANCE

Maternal antidepressant medication use during pregnancy has previously been associated with adverse outcomes in offspring, but to our knowledge, the association with intellectual disability (ID) has not been investigated.

OBJECTIVES

To examine the association of maternal antidepressant medication use during pregnancy with ID in offspring and investigate the importance of parental mental illness for such an association.

DESIGN, SETTING, AND PARTICIPANTS

A population-based cohort study of 179 007 children born from January 1, 2006, through December 31, 2007, with complete parental information from national registers who were followed up from birth throughout 2014.

MAIN OUTCOMES AND MEASURES

We estimated relative risks (RRs) and 95% CIs of ID in children exposed during pregnancy to any antidepressant medication or specifically to selective serotonin reuptake inhibitor (SSRI) antidepressants, all other non-SSRI antidepressants, or other nonantidepressant psychotropic medications. Analyses were adjusted for potential confounders. In addition to full population analyses, we used a subsample to compare mothers who used antidepressants during pregnancy with mothers who had at least one diagnosis of depression or anxiety before childbirth but did not use antidepressants during pregnancy.

RESULTS

Of the 179 007 children included in the study (mean [SD] age at end of follow-up, 7.9 [0.6] years; 92 133 [51.5%] male and 86 874 [48.5%] female), ID was diagnosed in 37 children (0.9%) exposed to antidepressants and in 819 children (0.5%) unexposed to antidepressants. With adjustment for potential confounders, the RR of ID after antidepressant exposure was estimated at 1.33 (95% CI, 0.90-1.98) in the full population sample and 1.64 (95% CI, 0.95-2.83) in the subsample of women with depression. Results from analyses of SSRI antidepressants, non-SSRI antidepressants, and nonantidepressant psychotropic medications and analyses in the clinically relevant subsample did not deviate from the full-sample results.

CONCLUSIONS AND RELEVANCE

The unadjusted RR of ID was increased in offspring born to mothers treated with antidepressants during pregnancy. After adjustment for confounding factors, however, the current study did not find evidence of an association between ID and maternal antidepressant medication use during pregnancy. Instead, the association may be attributable to a mechanism integral to other factors, such as parental age and mother's psychiatric disorder.

Maternal SSRI discontinuation, use, psychiatric disorder and the risk of autism in children: a meta-analysis of cohort studies

We undertook an exclusive meta-analysis of cohort studies investigating the possible link between prenatal selective serotonin reuptake inhibitor (SSRI) exposure and autism spectrum disorders (ASD) in children to further investigate our previous suggestion of confounding by indication. The point estimates regarding the following cohorts were extracted and pooled: (1) pregnant women who discontinued SSRI until 3 months before pregnancy; (2) pregnant women who were exposed to SSRI during pregnancy; and (3) pregnant women with maternal psychiatric disorder but no exposure to SSRI during pregnancy. Although the pooled point estimate of the first cohort showed a trend for increase, it did not reach significance. The pooled point estimates of the latter cohorts showed a significant association with ASD which strengthens our previous suggestion of confounding by indication. Future studies should be adequately designed to differentiate whether the previously suggested association is a result of maternal psychiatric disorder or SSRI exposure or both.

Links between serotonin reuptake inhibition during pregnancy and neurodevelopmental delay/spectrum disorders: A systematic review of epidemiological and physiological evidence

OBJECTIVE

To investigate possible linkages between neurodevelopmental delay and neurodevelopmental spectrum disorders and exposure to medication with effects on serotonin reuptake inhibition during pregnancy.

METHODS

We systematically reviewed the epidemiological literature for studies bearing on this relationship in children born with neurodevelopmental spectrum disorder and related conditions, as well as animal studies giving serotonin reuptake inhibitors to pregnant animals and in addition reviewed the literature for proposals as to possible mechanisms that might link effects on serotonin reuptake with cognitive changes post-partum.The epidemiological studies were analysed to produce Forest plots to illustrate possible relations.

RESULTS

The odds ratio of Autistic Spectrum or related Disorders in children born to women taking serotonin reuptake inhibiting antidepressants during pregnancy in case control studies was 1.95 (95% C.I. 1.63, 2.34) and in prospective cohort studies was 1.96 (95% C.I. 1.33, 2.90).

CONCLUSIONS

There appears to be a link between serotonin reuptake inhibition in pregnancy and developmental delay and spectrum disorders in infancy leading to cognitive difficulties in childhood. More work needs to be done to establish more precisely the nature of the difficulties and possible mechanisms through which this link might be mediated.

Protective effect or missed diagnosis? Females with autism spectrum disorder

Autism spectrum disorder (ASD) has historically been diagnosed more frequently in males than females. One explanation for this is the ‘female protective effect’: that there is something inherent in being female that makes girls and women less susceptible to ASD. Another possibility is that ASD is under-diagnosed in girls and women, due to the existence of a ‘female autism phenotype’, which is not well captured by current, male-biased diagnostic criteria. To evaluate the ‘female protective effect’ and ‘female autism phenotype’ hypotheses, this narrative review describes recent developments exploring the genetic underpinning and behavioral expression of ASD in females. We then look at the ways to better identify females with ASD who may be missed under the current diagnostic criteria.

Antidepressants during pregnancy and autism in offspring: population based cohort study

Objectives To study the association between maternal use of antidepressants during pregnancy and autism spectrum disorder (ASD) in offspring.Design Observational prospective cohort study with regression methods, propensity score matching, sibling controls, and negative control comparison.Setting Stockholm County, Sweden.Participants 254 610 individuals aged 4-17, including 5378 with autism, living in Stockholm County in 2001-11 who were born to mothers who did not take antidepressants and did not have any psychiatric disorder, mothers who took antidepressants during pregnancy, or mothers with psychiatric disorders who did not take antidepressants during pregnancy. Maternal antidepressant use was recorded during first antenatal interview or determined from prescription records.Main outcome measure Offspring diagnosis of autism spectrum disorder, with and without intellectual disability.Results Of the 3342 children exposed to antidepressants during pregnancy, 4.1% (n=136) had a diagnosis of autism compared with a 2.9% prevalence (n=353) in 12 325 children not exposed to antidepressants whose mothers had a history of a psychiatric disorder (adjusted odds ratio 1.45, 95% confidence interval 1.13 to 1.85). Propensity score analysis led to similar results. The results of a sibling control analysis were in the same direction, although with wider confidence intervals. In a negative control comparison, there was no evidence of any increased risk of autism in children whose fathers were prescribed antidepressants during the mothers' pregnancy (1.13, 0.68 to 1.88). In all analyses, the risk increase concerned only autism without intellectual disability.Conclusions The association between antidepressant use during pregnancy and autism, particularly autism without intellectual disability, might not solely be a byproduct of confounding. Study of the potential underlying biological mechanisms could help the understanding of modifiable mechanisms in the aetiology of autism. Importantly, the absolute risk of autism was small, and, hypothetically, if no pregnant women took antidepressants, the number of cases that could potentially be prevented would be small.

Maternal SSRI exposure increases the risk of autistic offspring: A meta-analysis and systematic review

BACKGROUND

Selective serotonin reuptake inhibitors (SSRIs) are the most common antidepressants used to preclude maternal pregnancy depression. There is a growing body of literature assessing the association of prenatal exposure to SSRIs with autism spectrum disorder (ASD). The present systematic review and meta-analysis reviewed the medical literature and pooled the results of the association of prenatal exposure to SSRIs with ASD.

METHODS

Published investigations in English by June 2016 with keywords of selective serotonin reuptake inhibitors, SSRI, autism spectrum disorder, ASD, pregnancy, childhood, children, neurodevelopment were identified using databases PubMed and PMC, MEDLINE, EMBASE, SCOPUS, and Google Scholar. Cochran's Q statistic-value (Q), degree of freedom (df), and I² indices (variation in odds ratio [OR] attributable to heterogeneity) were calculated to analyze the risk of heterogeneity of the within- and between-study variability. Pooled odds ratio (OR) and 95% confidence interval (CI) were reported by a Mantel-Haenszel test.

RESULTS

There was a non-significant heterogeneity for the included studies ([Q=3.61, df=6, P=0.730], I²=0%). The pooled results showed a significant association between prenatal SSRI exposure and ASD (OR=1.82, 95% CI=1.59-2.10, Z=8.49, P=0.00).

CONCLUSION

The evidence from the present study suggests that prenatal exposure to SSRIs is associated with a higher risk of ASD.

Effect of Maternal ±Citalopram Exposure on P11 Expression and Neurogenesis in the Mouse Fetal Brain

Fetal exposure to selective serotonin reuptake inhibitors (SSRI) has been associated with increased risk of adverse neurodevelopmental outcomes. In the adult brain, SSRI therapy regulates p11 (s100a10) expression and alters neurogenesis. The protein p11 indirectly regulates 5-HT signaling through 5-HT1B/D receptors. In the fetal brain, signaling through these receptors modulates axonal circuit formation. We determined whether p11 is expressed in the fetal mouse brain, and whether maternal SSRI exposure affects fetal p11 expression and neurogenesis. The SSRI ± citalopram was administered to pregnant mice from gestational day 8 to 17. Results show that p11 is expressed in fetal thalamic neurons and thalamocortical axons. Furthermore, p11 protein expression is significantly decreased in the fetal thalamus after in utero ±citalopram exposure compared to untreated controls, and neurogenesis is significantly decreased in specific fetal brain regions. These findings reveal differential regulation of p11 expression and altered neurogenesis in the fetal brain as a result of maternal SSRI exposure.

Perinatal SSRI exposure permanently alters cerebral serotonin receptor mRNA in mice but does not impact adult behaviors

PURPOSE

Associations have been made between maternal selective serotonin reuptake inhibitor (SSRI) use during pregnancy and altered behavior in offspring, including an increased risk of autism. Given the important role serotonin plays in behavior, we hypothesized SSRI exposure in the perinatal period would alter central serotonin receptor expression and program adult behaviors in mice.

METHODS

Female mice were injected with sertraline or saline throughout pregnancy. Offspring continued to receive injections on postnatal days 1-14, a time period in mice similar to the third trimester in human pregnancy. Adult offspring underwent behavioral testing, and serotonin receptor mRNA levels were quantified.

RESULTS

Compared to controls, SSRI exposed mice did not have a reduction in social interactions, spatial learning, or exploratory behavior. As adults, sertraline exposed mice had significantly increased mRNA levels of multiple 5-HT receptors, serotonin transporter (5-HTT), and tryptophan hydroxylase isoform 2 in the cerebral cortex.

CONCLUSION

Although no behavioral phenotype was observed, SSRI exposure in the perinatal period permanently alters cerebral receptor mRNA levels. We speculate these shifts in mRNA expression provide important compensation during SSRI exposure. Further pre-clinical and clinical investigation into additional serotonin-regulated phenotypes is necessary to further assess the long-term implications of perinatal SSRI exposure.

Associations of Maternal Antidepressant Use During the First Trimester of Pregnancy With Preterm Birth, Small for Gestational Age, Autism Spectrum Disorder, and Attention-Deficit/Hyperactivity Disorder in Offspring

IMPORTANCE

Prenatal antidepressant exposure has been associated with adverse outcomes. Previous studies, however, may not have adequately accounted for confounding.

OBJECTIVE

To evaluate alternative hypotheses for associations between first-trimester antidepressant exposure and birth and neurodevelopmental problems.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study included Swedish offspring born between 1996 and 2012 and followed up through 2013 or censored by death or emigration. Analyses controlling for pregnancy, maternal and paternal covariates, as well as sibling comparisons, timing of exposure comparisons, and paternal comparisons, were used to examine the associations.

EXPOSURES

Maternal self-reported first-trimester antidepressant use and first-trimester antidepressant dispensations.

MAIN OUTCOMES AND MEASURES

Preterm birth (<37 gestational weeks), small for gestational age (birth weight <2 SDs below the mean for gestational age), and first inpatient or outpatient clinical diagnosis of autism spectrum disorder and attention-deficit/hyperactivity disorder in offspring.

RESULTS

Among 1 580 629 offspring (mean gestational age, 279 days; 48.6% female; 1.4% [n = 22 544] with maternal first-trimester self-reported antidepressant use) born to 943 776 mothers (mean age at childbirth, 30 years), 6.98% of exposed vs 4.78% of unexposed offspring were preterm, 2.54% of exposed vs 2.19% of unexposed were small for gestational age, 5.28% of exposed vs 2.14% of unexposed were diagnosed with autism spectrum disorder by age 15 years, and 12.63% of exposed vs 5.46% of unexposed were diagnosed with attention-deficit/hyperactivity disorder by age 15 years. At the population level, first-trimester exposure was associated with all outcomes compared with unexposed offspring (preterm birth odds ratio [OR], 1.47 [95% CI, 1.40-1.55]; small for gestational age OR, 1.15 [95% CI, 1.06-1.25]; autism spectrum disorder hazard ratio [HR], 2.02 [95% CI, 1.80-2.26]; attention-deficit/hyperactivity disorder HR, 2.21 [95% CI, 2.04-2.39]). However, in models that compared siblings while adjusting for pregnancy, maternal, and paternal traits, first-trimester antidepressant exposure was associated with preterm birth (OR, 1.34 [95% CI, 1.18-1.52]) but not with small for gestational age (OR, 1.01 [95% CI, 0.81-1.25]), autism spectrum disorder (HR, 0.83 [95% CI, 0.62-1.13]), or attention-deficit/hyperactivity disorder (HR, 0.99 [95% CI, 0.79-1.25]). Results from analyses assessing associations with maternal dispensations before pregnancy and with paternal first-trimester dispensations were consistent with findings from the sibling comparisons.

CONCLUSIONS AND RELEVANCE

Among offspring born in Sweden, after accounting for confounding factors, first-trimester exposure to antidepressants, compared with no exposure, was associated with a small increased risk of preterm birth but no increased risk of small for gestational age, autism spectrum disorder, or attention-deficit/hyperactivity disorder.

Is there sexual dimorphism of hyperserotonemia in autism spectrum disorder?

Approximately 30% of individuals with autism spectrum disorder (ASD) have elevated whole blood serotonin (5-HT) levels. Genetic linkage and association studies of ASD and of whole blood 5-HT levels as a quantitative trait have revealed sexual dimorphism. Few studies have examined the presence of a sex difference on hyperserotonemia within ASD. To assess whether the rate of hyperserotonemia is different in males than in females with ASD, we measured whole blood 5-HT levels in 292 children and adolescents with ASD, the largest sample in which this biomarker has been assessed. Based upon previous work suggesting that hyperserotonemia is more common prior to puberty, we focused our analysis on the 182 pre-pubertal children with ASD. 42% of pre-pubertal participants were within the hyperserotonemia range. In this population, we found that males were significantly more likely to manifest hyperserotonemia than females (P = 0.03). As expected, no significant difference was found in the post-pubertal population. Additional work will be needed to replicate this intriguing finding and to understand whether it could potentially explain differences in patterns of ASD risk between males and females. Autism Res 2017, 10: 1417-1423. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Prenatal exposure to selective serotonin reuptake inhibitors and non-verbal cognitive functioning in childhood

Selective serotonin reuptake Inhibitors (SSRIs) are frequently used during pregnancy. Evidence about the long-term consequences of prenatal SSRI exposure on child neurodevelopment is controversial. We prospectively investigated whether prenatal SSRI exposure was associated with childhood non-verbal cognition in a population-based study, and contrasted it to exposure to depressive symptoms (without SSRIs). We included 71 children prenatally exposed to SSRIs, 385 children prenatally exposed to maternal depressive symptoms and 5427 unexposed children. Child executive functioning was assessed by maternal report at 4 years ( n=4020). Non-verbal intelligence was measured at 5 years ( n=5001) and children were tested with a neuropsychological battery at 7 years ( n=1194). Prenatal SSRI exposure was not related to maternal reported executive function at 4 years, nor was it related with observed non-verbal intelligence at age 5 or neuropsychological function at 7 years. Exposure to untreated maternal depressive symptoms was related to maternal reported shifting problems and emotional control problems at 4 years. No associations between exposure to depressive symptoms and observed non-verbal IQ at 5 years or neuropsychological function at 7 years were found. This population-based study suggests that neither SSRI use nor untreated depressive symptoms during pregnancy had a major impact on child non-verbal cognition.

Environmental factors influencing the risk of autism

Autism is a developmental disability with age of onset in childhood (under 3 years old), which is characterized by definite impairments in social interactions, abnormalities in speech, and stereotyped pattern of behaviors. Due to the progress of autism in recent decades, a wide range of studies have been done to identify the etiological factors of autism. It has been found that genetic and environmental factors are both involved in autism pathogenesis. Hence, in this review article, a set of environmental factors involved in the occurrence of autism has been collected, and finally, some practical recommendations for reduction of the risk of this devastating disease in children are represented.

Meconium exposure and autism risk

OBJECTIVE

This study aims to determine whether fetal meconium passage is associated with autism.

STUDY DESIGN

This retrospective birth cohort analysis of 9 945 896 children born in California 1991 to 2008 linked discharge diagnosis and procedure codes for prenatal stressors, meconium-stained amniotic fluid (MSAF) and meconium aspiration syndrome (MAS) with autism diagnoses for 47 277 children through 2012. We assessed the relative risk of autism by meconium status using logistic regression, adjusting for demographic and clinical features.

RESULTS

Children exposed to meconium (MSAF and MAS) were more likely to be diagnosed with autism in comparison with unexposed children (0.60% and 0.52%, vs 0.47%, respectively). In adjusted analyses, there was a small increase in autism risk associated with MSAF exposure (adjusted relative risk (aRR) 1.18, 95% confidence interval (CI) 1.12 to 1.25), and a marginal association that failed to achieve significance between MAS and autism (aRR 1.08, 95% CI 0.98 to 1.20).

CONCLUSION

Resuscitation of neonates with respiratory compromise from in utero meconium exposure may mitigate long-term neurodevelopmental damage.

Selective serotonin reuptake inhibitors for depression in pregnancy

Perinatal depression is associated with a high risk of morbidity and mortality and may have long-term consequences on child development. The US Preventive Services Task Force has recently recognized the importance of identifying and treating women with depression in the perinatal period. However, screening and accessing appropriate treatment come with logistical challenges. In many areas, there may not be sufficient access to psychiatric care, and, until these resources develop, the burden may inadvertently fall on obstetricians. As a result, understanding the risks of perinatal depression in comparison with the risks of treatment is important. Many studies of selective serotonin reuptake inhibitors in pregnancy fail to control for underlying depressive illness, which can lead to misinterpretation of selective serotonin reuptake inhibitor risk by clinicians. This review discusses the risks and benefits of selective serotonin reuptake inhibitor treatment in pregnancy within the context of perinatal depression. Whereas selective serotonin reuptake inhibitors may be associated with certain risks, the absolute risks are low and may be outweighed by the risks of untreated depression for many women and their offspring.

Neonatal and childhood neurodevelopmental, health and educational outcomes of children exposed to antidepressants and maternal depression during pregnancy: protocol for a retrospective population-based cohort study using linked administrative data

INTRODUCTION

Antidepressants are commonly prescribed during pregnancy; however, there are inconsistent data on the safety of these medications during the prenatal period. To address this gap, this study will investigate short-term and long-term neurodevelopmental, physical and mental health, and educational outcomes of children who have been exposed to selective serotonin reuptake inhibitors (SSRIs) or selective serotonin norepinephrine reuptake inhibitors (SNRIs) and/or maternal depression during pregnancy.

METHODS AND ANALYSIS

Administrative data will be linked to generate 4 population-based exposed groups from all children born in Manitoba between 1996 and 2014 whose mother had at least 2 prescriptions for either an SSRI or SNRI: (1) throughout the prenatal period (beginning of pregnancy until birth); (2) in the first trimester (≤14 weeks gestation); (3) in the second trimester (15-26 weeks gestation); (4) in the third trimester (≥27 weeks gestation) and 1 population-based unexposed group consisting of children whose mothers had a diagnosis of mood or anxiety disorder during pregnancy but did not use antidepressants. Propensity scores and inverse probability treatment weights will be used to adjust for confounding. Multivariate regression modelling will determine whether, compared with untreated mood/anxiety disorder, prenatal exposure to antidepressant medications is associated with: (1) adverse birth and neonatal outcomes, including: preterm birth, low birth weight, low Apgar scores, respiratory distress, congenital malformations and persistent pulmonary hypertension; (2) adverse early childhood outcomes, including: early childhood education challenges, diagnosis of neurodevelopmental disorders and diagnosis of mental disorders. We will determine if exposure effects differ between SSRIs and SRNIs, and determine if exposure effects differ between gestation timing of exposure to antidepressants.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the University of Manitoba Health Research Ethics Board. Dissemination of results will include engagement of stakeholders and patients, writing of reports for policymakers and patients, and publication of scientific papers.

Autism genes are selectively targeted by environmental pollutants including pesticides, heavy metals, bisphenol A, phthalates and many others in food, cosmetics or household products

The increasing incidence of autism suggests a major environmental influence. Epidemiology has implicated many candidates and genetics many susceptibility genes. Gene/environment interactions in autism were analysed using 206 autism susceptibility genes (ASG's) from the Autworks database to interrogate ∼1 million chemical/gene interactions in the comparative toxicogenomics database. Any bias towards ASG's was statistically determined for each chemical. Many suspect compounds identified in epidemiology, including tetrachlorodibenzodioxin, pesticides, particulate matter, benzo(a)pyrene, heavy metals, valproate, acetaminophen, SSRI's, cocaine, bisphenol A, phthalates, polyhalogenated biphenyls, flame retardants, diesel constituents, terbutaline and oxytocin, inter alia showed a significant degree of bias towards ASG's, as did relevant endogenous agents (retinoids, sex steroids, thyroxine, melatonin, folate, dopamine, serotonin). Numerous other suspected endocrine disruptors (over 100) selectively targeted ASG's including paraquat, atrazine and other pesticides not yet studied in autism and many compounds used in food, cosmetics or household products, including tretinoin, soy phytoestrogens, aspartame, titanium dioxide and sodium fluoride. Autism polymorphisms influence the sensitivity to some of these chemicals and these same genes play an important role in barrier function and control of respiratory cilia sweeping particulate matter from the airways. Pesticides, heavy metals and pollutants also disrupt barrier and/or ciliary function, which is regulated by sex steroids and by bitter/sweet taste receptors. Further epidemiological studies and neurodevelopmental and behavioural research is warranted to determine the relevance of large number of suspect candidates whose addition to the environment, household, food and cosmetics might be fuelling the autism epidemic in a gene-dependent manner.

Phenotyping, Etiological Factors, and Biomarkers: Toward Precision Medicine in Autism Spectrum Disorders

Despite the progress made in understanding the biology of autism spectrum disorder (ASD), effective biological interventions for the core symptoms remain elusive. Because of the etiological heterogeneity of ASD, identification of a "one-size-fits-all" treatment approach will likely continue to be challenging. A meeting was convened at the University of Missouri and the Thompson Center to discuss strategies for stratifying patients with ASD for the purpose of moving toward precision medicine. The "white paper" presented here articulates the challenges involved and provides suggestions for future solutions.

Prenatal selective serotonin reuptake inhibitor use and the risk of autism spectrum disorder in children: A systematic review and meta-analysis

OBJECTIVE

To determine whether an up-to-date systematic review and meta-analysis of observational studies would support the previously suggested associations regarding prenatal selective serotonin reuptake inhibitor (SSRI) use and the risk for autism spectrum disorders (ASD) in children.

METHODS

PubMed/MEDLINE, Cochrane Central Register of Controlled Trials and Reprotox databases were searched; observational studies with an exposed and unexposed group were included.

RESULTS

The meta-analysis of case-control studies demonstrated a significantly increased risk of ASD in the children whose mothers were prenatally exposed to SSRIs during different exposure time windows (except third trimester). The qualitative review of the cohort studies suggested inconsistent findings.

CONCLUSIONS

The significant association between preconception-only SSRI exposure and ASD in the children and negative/inconsistent findings among cohort studies weaken the significant associations detected in this meta-analysis. We suggest that confounding by indication still cannot be ruled out regarding prenatal SSRI exposure and ASD in children.

Antenatal depression, treatment with selective serotonin reuptake inhibitors, and neonatal brain structure: A propensity-matched cohort study

The aim of this propensity-matched cohort study was to evaluate the impact of prenatal SSRI exposure and a history of maternal depression on neonatal brain volumes and white matter microstructure. SSRI-exposed neonates (n=27) were matched to children of mothers with no history of depression or SSRI use (n=54). Additionally, neonates of mothers with a history of depression, but no prenatal SSRI exposure (n=41), were matched to children of mothers with no history of depression or SSRI use (n=82). Structural magnetic resonance imaging and diffusion weighted imaging scans were acquired with a 3T Siemens Allegra scanner. Global tissue volumes were characterized using an automatic, atlas-moderated expectation maximization segmentation tool. Local differences in gray matter volumes were examined using deformation-based morphometry. Quantitative tractography was performed using an adaptation of the UNC-Utah NA-MIC DTI framework. SSRI-exposed neonates exhibited widespread changes in white matter microstructure compared to matched controls. Children exposed to a history of maternal depression but no SSRIs showed no significant differences in brain development compared to matched controls. No significant differences were found in global or regional tissue volumes. Additional research is needed to clarify whether SSRIs directly alter white matter development or whether this relationship is mediated by depressive symptoms during pregnancy.

Autism spectrum disorder and prenatal exposure to selective serotonin reuptake inhibitors: A systematic review and meta-analysis

To obtain the risk estimates of autism spectrum disorder (ASD) in the offspring exposed to serotonin reuptake inhibitors (SSRI) in utero, we performed systematic review and meta-analysis of relevant studies. Five case-control and three cohort studies were eligible for the analysis. The SSRI group had significantly higher risk of ASD than the SSRI non-exposed group (pooled OR 1.45, 95% CI 1.15-1.82). In the subgroup analyses, however, the risk of ASD was similar between the SSRI group and other antidepressants group (pooled OR 1.14, 95% CI 0.67-1.96). Furthermore, when the analysis was confined to those born to the women with psychiatric disorders, the SSRI group did not show an increased ASD risk (pooled OR 0.96, 95% CI 0.57-1.63) compared to non-exposed groups. In conclusion, SSRI use in pregnancy is associated with an increased risk of ASD in the offspring, but maternal psychiatric condition is a major confounding factor.

Genetic Syndromes, Maternal Diseases and Antenatal Factors Associated with Autism Spectrum Disorders (ASD)

Autism spectrum disorder (ASD) affecting about 1% of all children is associated, in addition to complex genetic factors, with a variety of prenatal, perinatal, and postnatal etiologies. In addition, ASD is often an important clinical presentation of some well-known genetic syndromes in human. We discuss these syndromes as well as the role of the more important prenatal factors affecting the fetus throughout pregnancy which may also be associated with ASD. Among the genetic disorders we find Fragile X, Rett syndrome, tuberous sclerosis, Timothy syndrome, Phelan-McDermid syndrome, Hamartoma tumor syndrome, Prader-Willi and Angelman syndromes, and a few others. Among the maternal diseases in pregnancy associated with ASD are diabetes mellitus (PGDM and/or GDM), some maternal autoimmune diseases like antiphospholipid syndrome (APLS) with anti-β2GP1 IgG antibodies and thyroid disease with anti-thyroid peroxidase (TPO) antibodies, preeclampsia and some other autoimmune diseases with IgG antibodies that might affect fetal brain development. Other related factors are maternal infections (rubella and CMV with fetal brain injuries, and possibly Influenza with fever), prolonged fever and maternal inflammation, especially with changes in a variety of inflammatory cytokines and antibodies that cross the placenta and affect the fetal brain. Among the drugs are valproic acid, thalidomide, misoprostol, and possibly SSRIs. β2-adrenergic receptor agonists and paracetamol have also lately been associated with increased rate of ASD but the data is too preliminary and inconclusive. Associations were also described with ethanol, cocaine, and possibly heavy metals, heavy smoking, and folic acid deficiency. Recent studies show that heavy exposure to pesticides and air pollution, especially particulate matter < 2.5 and 10 μm in diameter (PM2.5 and PM10) during pregnancy is also associated with ASD. Finally, we have to remember that many of the associations mentioned in this review are only partially proven, and not all are "clean" of different confounding factors. The associations described in this review emphasize again how little we know about the etiology and pathogenesis of ASD. It is obvious that we need more epidemiologic data to establish many of these associations, but if proven, they might be promising avenues for prevention.

Of rodents and humans: A comparative review of the neurobehavioral effects of early life SSRI exposure in preclinical and clinical research

Selective serotonin reuptake inhibitors (SSRIs) have been a mainstay pharmacological treatment for women experiencing depression during pregnancy and postpartum for the past 25 years. SSRIs act via blockade of the presynaptic serotonin transporter and result in a transient increase in synaptic serotonin. Long-lasting changes in cellular function such as serotonergic transmission, neurogenesis, and epigenetics, are thought to underlie the therapeutic benefits of SSRIs. In recent years, though, growing evidence in clinical and preclinical settings indicate that offspring exposed to SSRIs in utero or as neonates exhibit long-lasting behavioral adaptions. Clinically, children exposed to SSRIs in early life exhibit increased internalizing behavior reduced social behavior, and increased risk for depression in adolescence. Similarly, rodents exposed to SSRIs perinatally exhibit increased traits of anxiety- or depression-like behavior. Furthermore, certain individuals appear to be more susceptible to early life SSRI exposure than others, suggesting that perinatal SSRI exposure may pose greater risks for negative outcome within certain populations. Although SSRIs trigger a number of intracellular processes that likely contribute to their therapeutic effects, early life antidepressant exposure during critical neurodevelopmental periods may elicit lasting negative effects in offspring. In this review, we cover the basic development and structure of the serotonin system, how the system is affected by early life SSRI exposure, and the behavioral outcomes of perinatal SSRI exposure in both clinical and preclinical settings. We review recent evidence indicating that perinatal SSRI exposure perturbs the developing limbic system, including altered serotonergic transmission, neurogenesis, and epigenetic processes in the hippocampus, which may contribute to behavioral domains (e.g., sociability, cognition, anxiety, and behavioral despair) that are affected by perinatal SSRI treatment. Identifying the molecular mechanisms that underlie the deleterious behavioral effects of perinatal SSRI exposure may highlight biological mechanisms in the etiology of mood disorders. Moreover, because recent studies suggest that certain individuals may be more susceptible to the negative consequences of early life SSRI exposure than others, understanding mechanisms that drive such susceptibility could lead to individualized treatment strategies for depressed women who are or plan to become pregnant.

Safety of Selective Serotonin Reuptake Inhibitors in Pregnancy: A Review of Current Evidence

Selective serotonin reuptake inhibitors (SSRIs) are the most commonly prescribed antidepressant medications worldwide. However, over the past decade, their use during pregnancy, a period of extreme vulnerability to the onset of depression, has become highly concerning to patients and their healthcare providers in terms of safety to the developing fetus. Exposure to SSRIs in pregnancy has been associated with miscarriage, premature delivery, neonatal complications, birth defects-specifically cardiac defects-and, more recently, neurodevelopmental disorders in childhood, specifically autism spectrum disorders. Studies addressing the effect of individual SSRIs indicate a small but higher risk for birth defects with maternal fluoxetine and paroxetine use. Though the excess in absolute risk is small, it may still be of concern to some patients. Meanwhile, antenatal depression itself is associated with adverse perinatal outcomes, and discontinuing antidepressant treatment during pregnancy is associated with a high risk of relapse of depression. Whether the observed adverse fetal effects are related to the mother's medication use or her underlying maternal illness remains difficult to determine. It is important that every pregnant woman being treated with an SSRI (or considering such treatment) carefully weighs the risks of treatment against the risk of untreated depression for both herself and her child. The importance of recognizing a higher risk for the development of adverse outcomes lies in the potential for surveillance and possibly a timely intervention. Therefore, we recommend that pregnant women exposed to any SSRI in early pregnancy be offered options for prenatal diagnosis through ultrasound examinations and fetal echocardiography to detect the presence of birth defects. Tapering off or switching to other therapy in early pregnancy, if appropriate for the individual, may also be considered on a case-by-case basis.

Perinatal reduction of functional serotonin transporters results in developmental delay

While there is strong evidence from rodent and human studies that a reduction in serotonin transporter (5-HTT) function in early-life can increase the risk for several neuropsychiatric disorders in adulthood, the effects of reduced 5-HTT function on behavior across developmental stages are underinvestigated. To elucidate how perinatal pharmacological and lifelong genetic inactivation of the 5-HTT affects behavior across development, we conducted a battery of behavioral tests in rats perinatally exposed to fluoxetine or vehicle and in 5-HTT(-/-) versus 5-HTT(+/+) rats. We measured motor-related behavior, olfactory function, grooming behavior, sensorimotor gating, object directed behavior and novel object recognition in the first three postnatal weeks and if possible the tests were repeated in adolescence and adulthood. We also measured developmental milestones such as eye opening, reflex development and body weight. We observed that both pharmacological and genetic inactivation of 5-HTT resulted in a developmental delay. Except for hypo-locomotion, most of the observed early-life effects were normalized later in life. In adolescence and adulthood we observed object directed behavior and decreased novel object recognition in the 5-HTT(-/-) rats, which might be related to the lifelong inactivation of 5-HTT. Together, these data provide an important contribution to the understanding of the effects of perinatal and lifelong 5-HTT inactivation on behavior across developmental stages.