Prenatal Cannabis Exposure and Infant Development: “A Tolerated Matter”

Since centuries, cannabis is used for recreational, spiritual and medicinal purposes. Today, cannabis is one of the most commonly used illicit substances, also among pregnant women. In the last decades, levels of Δ9-tetrahydrocannabinol in cannabis products have increased, and these higher levels contributed to our interest for investigating the effects of cannabis during pregnancy. The study described in this thesis was embedded within the Generation R Study, a prospective cohort study from foetal life onwards in a multiethnic urban population. In this study, we examined the associations of maternal cannabis use during pregnancy and several offspring outcomes. In order to determine whether cannabis use affects children because of intrauterine exposure, the possible influence of confounding factors should be considered. Moreover, the direct biological effect of intrauterine exposure was addressed by comparing the strength of the associations between maternal and paternal cannabis use during pregnancy and foetal growth using ultrasound measures. Additionally, to determine whether exposure to cannabis has an intrauterine influence or not, the timing of exposure was considered as well, i.e. the comparison between maternal cannabis use only before pregnancy and during pregnancy was made. This manuscript described the determinants of maternal cannabis use during pregnancy. Additionally, it discussed the agreement between maternal self-report of cannabis use during pregnancy and the presence of cannabis metabolites in urine. We addressed the association between maternal and paternal cannabis use and foetal growth and foetal redistribution observed using ultrasound measurements. Finally, this thesis focuses on the relation between parental cannabis use and child behavioural development and verbal and non-verbal cognitive development

Intrauterine Exposure to Antidepressants or Maternal Depressive Symptoms and Offspring Brain White Matter Trajectories From Late Childhood to Adolescence

Background: During pregnancy, both selective serotonin reuptake inhibitor (SSRI) exposure and maternal depression have been associated with poor offspring neurodevelopmental outcomes. In a population-based cohort, we investigated the association between intrauterine exposure to SSRIs and depressive symptoms and offspring white matter development from childhood to adolescence. Methods: Self-reported SSRI use was verified by pharmacy records. In midpregnancy, women reported on depressive symptoms using the Brief Symptom Inventory. Using diffusion tensor imaging, offspring white matter microstructure, including whole-brain and tract-specific fractional anisotropy (FA) and mean diffusivity, was measured at 3 assessments between ages 7 to 15 years. The participants were divided into 4 groups: prenatal SSRI exposure (n = 37 with 60 scans), prenatal depression exposure (n = 229 with 367 scans), SSRI use before pregnancy (n = 72 with 95 scans), and reference (n = 2640 with 4030 scans). Results: Intrauterine exposure to SSRIs and depressive symptoms were associated with lower FA in the whole-brain and the forceps minor at 7 years. Exposure to higher prenatal depressive symptom scores was associated with lower FA in the uncinate fasciculus, cingulum bundle, superior and inferior longitudinal fasciculi, and corticospinal tracts. From ages 7 to 15 years, children exposed to prenatal depressive symptoms showed a faster increase in FA in these white matter tracts. Prenatal SSRI exposure was not related to white matter microstructure growth over and above exposure to depressive symptoms.Conclusions: These results suggest that prenatal exposure to maternal depressive symptoms was negatively associated with white matter microstructure in childhood, but these differences attenuated during development, suggesting catch-up growth.</p

Intrauterine Exposure to Antidepressants or Maternal Depressive Symptoms and Offspring Brain White Matter Trajectories From Late Childhood to Adolescence

Background: During pregnancy, both selective serotonin reuptake inhibitor (SSRI) exposure and maternal depression have been associated with poor offspring neurodevelopmental outcomes. In a population-based cohort, we investigated the association between intrauterine exposure to SSRIs and depressive symptoms and offspring white matter development from childhood to adolescence. Methods: Self-reported SSRI use was verified by pharmacy records. In midpregnancy, women reported on depressive symptoms using the Brief Symptom Inventory. Using diffusion tensor imaging, offspring white matter microstructure, including whole-brain and tract-specific fractional anisotropy (FA) and mean diffusivity, was measured at 3 assessments between ages 7 to 15 years. The participants were divided into 4 groups: prenatal SSRI exposure (n = 37 with 60 scans), prenatal depression exposure (n = 229 with 367 scans), SSRI use before pregnancy (n = 72 with 95 scans), and reference (n = 2640 with 4030 scans). Results: Intrauterine exposure to SSRIs and depressive symptoms were associated with lower FA in the whole-brain and the forceps minor at 7 years. Exposure to higher prenatal depressive symptom scores was associated with lower FA in the uncinate fasciculus, cingulum bundle, superior and inferior longitudinal fasciculi, and corticospinal tracts. From ages 7 to 15 years, children exposed to prenatal depressive symptoms showed a faster increase in FA in these white matter tracts. Prenatal SSRI exposure was not related to white matter microstructure growth over and above exposure to depressive symptoms.Conclusions: These results suggest that prenatal exposure to maternal depressive symptoms was negatively associated with white matter microstructure in childhood, but these differences attenuated during development, suggesting catch-up growth.</p

Examining associations between brain morphology in late childhood and early alcohol or tobacco use initiation in adolescence:findings from a large prospective cohort

A prominent challenge in understanding neural consequences of substance use involves disentangling predispositional risk factors from resulting consequences of substance use. Existing literature has identified pre-existing brain variations as vulnerability markers for substance use throughout adolescence. As early initiation of use is an important predictor for later substance use problems, we examined whether pre-existing brain variations are associated with early initiation of use. In the Generation R Study, a prospective population-based cohort, brain morphology (gray matter volume, cortical thickness and surface area) was assessed at ages 10 and 14 using neuroimaging. In the second wave, participants reported on alcohol and tobacco use initiation. From a base study population (N = 3019), we examined the longitudinal (N = 2218) and cross-sectional (N = 1817) association between brain morphology of frontolimbic regions of interest known to be associated with substance use risk, and very early (age &lt; 13) alcohol/tobacco use initiation. Additionally, longitudinal and cross-sectional associations were examined with a brain surface-based approach. Models were adjusted for age at neuroimaging, sex and relevant sociodemographic factors. No associations were found between brain morphology (ages 10 and 14) and early alcohol/tobacco use initiation (&lt;13 years). Sex-specific analyses suggested a cross-sectional association between smaller brain volume and early initiated tobacco use in girls. Our findings are important for interpreting studies examining neural consequences of substance use in the general population. Future longitudinal studies are needed to specify whether these findings can be extended to initiation and continuation of alcohol/tobacco use in later stages of adolescence.</p

A Prospective Cohort Study on the Intergenerational Transmission of Childhood Adversity and Subsequent Risk of Psychotic Experiences in Adolescence

BACKGROUND AND HYPOTHESIS: Previous studies have shown a robust relationship between childhood adversity and subsequent psychotic symptoms. However, the role of familial risk factors underlying this relationship remains largely unclear. Here, we tested whether offspring childhood adversity and postnatal maternal psychopathology mediated the relationship between maternal childhood adversity and offspring psychotic experiences. STUDY DESIGN: N = 3068 mother-offspring dyads were included. Maternal history of childhood adversity was retrospectively assessed using the Childhood Trauma Questionnaire during pregnancy. Maternal psychopathology was assessed during and after pregnancy. Twenty-four offspring childhood adversities were assessed by maternal interview when the child was 10 years old. Offspring psychotic experiences were examined using self-report at 14 years. Structural equation mediation models were conducted to explore whether maternal postnatal psychopathology and offspring childhood adversities sequentially mediated the relationship between maternal childhood adversity and offspring psychotic experiences. Analyses were adjusted for sociodemographic confounders. STUDY RESULTS: Maternal history of childhood adversity was associated with offspring childhood adversities (β = 0.12, 95% CI: 0.09 to 0.16). Offspring childhood adversity mediated the association of maternal childhood adversity with offspring hallucinations (βindirect effect = 0.008, 95% CI: 0.002 to 0.014, proportion mediated = 16.3%) and delusions (βindirect effect = 0.006, 95% CI: 0.000 to 0.012, proportion mediated = 13.1%). CONCLUSIONS: Intergenerational transmission of childhood adversity can be considered of relevance in the etiology of psychosis vulnerability and can potentially serve as a modifiable risk factor

Maternal Sociodemographic Factors Are Associated With Methylphenidate Initiation in Children in the Netherlands: A Population-Based Study

Multiple factors may contribute to the decision to initiate methylphenidate treatment in children such as maternal sociodemographic factors of which relatively little is known. The objective was to investigate the association between these factors and methylphenidate initiation. The study population included 4243 children from the Generation R Study in the Netherlands. Maternal sociodemographic characteristics were tested as determinants of methylphenidate initiation through a timedependent Cox regression analysis. Subsequently, we stratifed by mother-reported ADHD symptoms (present in 4.2% of the study population). When ADHD symptoms were absent, we found that girls (adjusted HR 0.25, 95%CI 0.16–0.39) and children born to a mother with a non-western ethnicity (compared to Dutch-Caucasian) (adjusted HR 0.42, 95%CI 015–0.68) were less likely to receive methylphenidate. They were more likely to receive methylphenidate when their mother completed a low (adjusted HR 2.29, 95%CI 1.10–4.77) or secondary (adjusted HR 1.71, 95%CI 1.16–2.54) education. In conclusion, boys and children born to a mother of Dutch-Caucasian ethnicity were more likely to receive methylphenidate, irrespective of the presence of ADHD symptoms