Sex moderates the impact of birth weight on child externalizing psychopathology.

Abstract

Low birth weight (LBW) has consistently been associated with childhood attention- deficit hyperactivity disorder (ADHD), and a similar association has been found for childhood externalizing disorders, such as oppositional defiant disorder (ODD) and conduct disorder (CD), albeit to a lesser degree. Although the association between LBW and these disorders has been robustly replicated, few studies have adequately controlled for confounding variables, such as parental age at birth and prenatal tobacco use, examined the specificity of the risk of LBW for ADHD symptoms, or investigated potential nonlinear (i.e., quadratic) effects of birth weight. Additionally, the extent to which LBW confers risk for these disorders depending on childhood sex has rarely been examined. The current study examined associations between birth weight and ADHD, ODD, and CD symptom dimensions as well as the extent to which such associations are moderated by child sex, while also controlling for confounding variables. Significant interactions between sex and birth weight emerged across all analyses predicting ADHD and externalizing psychopathology, such that associations were stronger in males relative to females. Results remained when controlling for a number of confounds, including parental age, prenatal tobacco use, comorbid psychopathology, as well as other indicators of maternal and child health during the pre- and perinatal period. Both linear and quadratic associations emerged between birth weight and both hyperactivity and CD symptoms, whereas birth weight predicted inattention and ODD symptoms in a linear fashion. Future research should continue to investigate the impact of birth weight on ADHD and externalizing psychopathology, in particular the biological mechanisms underlying this association.

Birth weight is associated with adolescent brain development: A multimodal imaging study in monozygotic twins

“…We found a more robust association between BW and limbic connectivity in males than in females, which is in line with some behavioral studies; for example, the association between BW and various types of externalizing behaviors are more pronounced in adolescent boys than in adolescent girls (Momany et al, 2017). As suggested by Momany et al (2017), males may be more sensitive to prenatal adversities than females, potentially due in part to higher prenatal levels of testosterone, which, in turn, may contribute to sex dimorphism in brain development and subsequent behavioral outcomes.…”

A Meta-Analysis of the Association Between Birth Weight and Attention Deficit Hyperactivity Disorder

“…However, a nonlinear association would be more conclusively demonstrated via the use of continuous measures of birth weight and ADHD symptoms. A recent study by Momany and colleagues (2016) tested such a nonlinear association using continuous measurements, and found the nonlinear association to be significant in predicting hyperactivity-impulsivity. However, few, if any, other studies have examined the nonlinear association between birth weight and ADHD using continuous measures.…”

“…In addition to considering factors associated with birth weight and ADHD, it is also important to consider the extent to which the correlation between ADHD and birth weight may vary based on sex, given the large sex difference in the prevalence of ADHD (Akinbami, Xiang, Pastor, & Reuben, 2011; Visser et al, 2014). Previous studies have rarely examined sex as a moderator of the association between birth weight and ADHD symptoms, and the few studies that have examined sex as a moderator have produced mixed results (Momany et al, 2016; Murray et al, 2015). A recent review by Martel (2013) proposed that Sexual Selection Theory could explain the sex difference observed in ADHD.…”

Parental age and developmental milestones: pilot study indicated a role in understanding ADHD severity in Indian probands

“…In the Caucasoid population, birth weight was speculated as a prime risk factor for developing ADHD symptoms, primarily inattention [30, 34–36]. In the Indo-Caucasoid population, we have noticed substantial influence of B_weight on the delivery process and developmental milestones which were associated further with symptom scores; preterm children showed lower score for BPr/AI.…”