Resting autonomic nervous system activity is unrelated to antisocial behaviour dimensions in adolescents: Cross-sectional findings from a European multi-centre study

Purpose: Autonomic nervous system (ANS) functioning has long been studied in relation to antisocial behaviour, but relevant measures (heart rate, heart rate variability, pre-ejection period, respiration rate) have rarely been considered together. This study investigated the relationship between these measures and antisocial behaviour. Methods: Using a sample of 1010 youths with (47.8%) and without conduct disorder (52.2%) aged between 9 and 18. years (659 females, 351 males, mean age = 14.2. years, SD = 2.4), principal component analysis (PCA) was applied to various measures of psychopathology and antisocial behavior. Structural equation modelling was performed in order to test whether the ANS measures predicted PCA-dimensions. Cluster analysis was used in order to classify patterns of ANS activity. Analyses were performed separately for males/females and controlled for body-mass-index, age, caffeine use, cigarette smoking, sports, socioeconomic status, medication, cardiac problems. Results: The PCA yielded three components: antisocial behaviour/comorbid psychopathology, narcissistic traits, and callous-unemotional traits. ANS measures were only weakly correlated with these components. Cluster analysis yielded high and low arousal clusters in both sexes. When controlling for covariates, all associations disappeared. Conclusion: Our findings suggest that resting ANS measures are only weakly related to antisocial behaviour and indicate that smoking should be considered as an important covariate in future psychophysiological studies

CES1 and SLC6A2 Genetic Variants As Predictors of Response To Methylphenidate in Autism Spectrum Disorders

Altres ajuts: Secretaria de Recerca i Universitats de la Generalitat de Catalunya i Universitat Ramon Llull (2021-URL-Proj-002).Purpose: Autistic spectrum disorders (ASD) children and adolescents usually present comorbidities, with 40-70% of them affected by attention deficit hyperactivity disorders (ADHD). The first option of pharmacological treatment for these patients is methylphe-nidate (MPH). ASD children present more side effects and poorer responses to MPH than ADHD children. The objective of our study is to identify genetic biomarkers of response to MPH in ASD children and adolescents to improve its efficacy and safety. Patients and Methods: A retrospective study with a total of 140 ASD children and adolescents on MPH treatment was included. Fifteen polymorphisms within genes coding for the MPH target NET1 (SLC6A2) and for its primary metabolic pathway (CES1) were genotyped. Multivariate analyses including response phenotypes (efficacy, side-effects, presence of somnolence, irritability, mood alterations, aggressivity, shutdown, other side-effects) were performed for every polymorphism and haplotype. Results: Single marker analyses considering gender, age, and dose as covariates showed association between CES1 variants and MPH-induced side effects (rs2244613-G (p=0.04), rs2302722-C (p=0.02), rs2307235-A (p=0.03), and rs8192950-T alleles (p=0.03)), and marginal association between the CES1 rs2302722-C allele and presence of somnolence (p=0.05) and the SLC6A2 rs36029-G allele and shutdown (p=0.05). A CES1 haplotype combination was associated with efficacy and side effects (p=0.02 and 0.03 respectively). SLC6A2 haplotype combination was associated with somnolence (p=0.05). Conclusion: CES1 genetic variants may influence the clinical outcome of MPH treatment in ASD comorbid with ADHD children and adolescents

Pharmacogenetic influences on the response to pharmacological treatment in autism spectrum disorders

Aim: About a third of patients with autism spectrum disorder (ASD) receive pharmacological treatment for comorbid symptoms. However, 30%-50% do not respond adequately and/or present severe and long-lasting side effects. Previous studies have reported the influence of variants in genes coding for drug targets on the efficacy and safety of pharmacological treatments, including genetic polymorphisms in dopaminergic and serotonergic systems. However, most studies have focused on the adult population, with relatively few studies in children and adolescents, and no clear biomarkers of response have been reported in these populations. The aim of our study was to identify genetic predictors of drug response in patients with ASD. This information may be used to personalise pharmacological treatment and improve the efficacy and safety of psychotropic drugs in patients with ASD. Methods: Genetic variants in dopaminergic and serotonergic drug targets (SLC6A3, DRD2, DRDRD3, DRD4, HTR2A, and HTR2C) and in other genes previously associated with treatment efficacy and/or induced side effects (ANKK1, BDNF, COMT, and HTR1A) were investigated in 176 children and adolescents diagnosed with ASD and undergoing pharmacological treatment. Results: A SLC6A3 genetic variant was associated with response to methylphenidate in our ASD cohort, whereas HTR2A and HTR2C allele and haplotype distributions were associated with adverse reactions such as somnolence, mood alterations, and BMI. ANKK1, COMT, and BDNF genetic variants were mainly associated with treatment side effects.Conclusion: If confirmed, these genetic variants may be used as predictors of clinical outcome and help to personalise pharmacological treatments in patients with ASD

Baseline autonomic nervous system activity in female children and adolescents with conduct disorder:Psychophysiological findings from the FemNAT-CD study

Purpose: Autonomic nervous system (ANS) functioning has been widely studied in relation to antisocial behavior, such as Conduct Disorder (CD). However, research in females is scarce and findings are inconsistent. This study investigated baseline ANS activity in CD children and adolescents and tested for sex differences. Furthermore, subgroups of CD were investigated: +/‐ Limited Prosocial Emotions (LPE), +/‐ comorbid internalizing disorders (INT). Methods: Baseline ANS activity was measured by Heart Rate (HR), Heart Rate Variability (HRV; parasympathetic activity), Pre-Ejection Period (PEP; sympathetic activity), and Respiration Rate (RR). 659 females (296 CD, 363 controls) and 351 males (187 CD, 164 controls), aged 9–18 years participated. Results: Baseline HR, HRV and PEP did not differ between CD subjects and controls in both sexes. RR was higher in CD participants than controls amongst females, but not males. LPE was unrelated to ANS activity, whereas females with CD + INT presented lower HRV. Conclusions: These results suggest that baseline ANS activity is not a robust indicator for CD. However, deviant ANS activity – especially parasympathetic activity - was observed in CD females with internalizing comorbidity. The psychophysiological abnormalities observed in this subgroup are indicative of emotion regulation problems. Accordingly, this subgroup may require specific interventions

Paternally inherited cis-regulatory structural variants are associated with autism.

The genetic basis of autism spectrum disorder (ASD) is known to consist of contributions from de novo mutations in variant-intolerant genes. We hypothesize that rare inherited structural variants in cis-regulatory elements (CRE-SVs) of these genes also contribute to ASD. We investigated this by assessing the evidence for natural selection and transmission distortion of CRE-SVs in whole genomes of 9274 subjects from 2600 families affected by ASD. In a discovery cohort of 829 families, structural variants were depleted within promoters and untranslated regions, and paternally inherited CRE-SVs were preferentially transmitted to affected offspring and not to their unaffected siblings. The association of paternal CRE-SVs was replicated in an independent sample of 1771 families. Our results suggest that rare inherited noncoding variants predispose children to ASD, with differing contributions from each parent