2010

Background: The three-way interaction between the functional polymorphism in the serotonin transporter gene linked promotor region (5-HTTLPR), the val66met polymorphism in the brain-derived neurotrophic factor (BDNF) gene, and childhood adversity in the prediction of depression in children, reported by Kaufman and colleagues in 2006, has only been confirmed in adult samples. This study examines the gene-by-gene-by-environment interaction in an adolescent sample. Methods: In a longitudinal population-based study depression scores were assessed with the Youth Self Report at ages 11, 13.5 and 16. Pre- and perinatal adversities and childhood events were assessed in a parent interview at age 11. Long term difficulties until age 11 were assessed with a parent questionnaire at age 13.5. Blood or buccal cells were collected for genotyping at age 16. The study included 1096 complete data sets.
Results: Depression score over the three measurements was not significantly predicted by any interaction between genotypes and childhood adversities. Conclusions: We were not able to confirm the three-way interaction in a representative, population based sample of adolescents. The large sample resulted in adequate power, in combination with the reliability of our measures, this gives confidence in our findings.

Copyright 2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

The present study investigated whether autonomic flexibility predicted future anxiety levels in adolescent boys and girls. This study is part of the TRacking Adolescents' Individual Lives
Survey (TRAILS), a prospective cohort study of Dutch adolescents. The current study included a subsample of 965 individuals. Measures of autonomic flexibility, i.e. heart rate (HR) and respiratory sinus arrhythmia (RSA), were determined during the first assessment wave (T1: participants 10-12 years old). Self-reported anxiety was assessed at the first and second assessment wave (T2: participants 12-14 years old). Possible gender differences and co-occurring depressive problems were examined. In girls, low RSA predicted anxiety levels two years later. In boys, no associations between HR or RSA and future anxiety were found. We conclude that in adolescent girls from the general population, signs of reduced autonomic flexibility (i.e. low RSA) predict future anxiety levels. Since the effect size was small, at this point, RSA reactivity alone cannot be used to identify individuals at risk for anxiety, but should be regarded as one factor within a large group of risk factors. However, if the present findings are replicated in clinical studies, - in the future - intervention programs aimed at normalizing autonomic functioning may be helpful.

Background: It is well known that functional somatic symptoms (FSS) are associated with anxiety and depression. However, evidence is lacking about how they are related to FSS. The aim of this study was to clarify these relationships and examine whether anxiety and depression are distinctly related to FSS. We hypothesized that anxiety contributes to the development of FSS and that depression is a consequence of FSS. Methods: FSS, anxiety, and depression were measured in adolescents (N = 2230, 51% women) by subscales of the Youth Self-Report during three assessment waves (adolescents successively aged: 10–12, 12–14, and 14–17) and by corresponding subscales of the Child Behavior Checklist. Using structural equation models, we combined trait and state models of FSS with those of anxiety and depression, respectively. We identified which relationships (contemporaneous and two-year lagged) significantly connected the states of FSS with the states of anxiety and depression. Results: Trait variables were all highly interrelated (r = .54–.63). Contrary to our hypothesis, both state anxiety (b = .35) and state depression (b = .45) had a strong contemporaneous effect on state FSS. In turn, state FSS had a weak two-year lagged effect on state anxiety (b = .11) and an even weaker effect on state depression (b = .06).
Conclusions: While the effect of anxiety and depression on FSS is strong and immediate, FSS exert a weaker and delayed influence on anxiety and depression. Further research should be done to detect the exact ways in which anxiety and depression lead to FSS, and FSS lead to anxiety and depression.

For prevention of anxiety in children and adolescents, it is important to know whether family stress is a predictor of anxiety. We studied this in 1,875 adolescents from the Tracking Adolescents’ Individual Lives Survey (TRAILS) who were followed-up for two years, from age 10-12 to 12-14 years. Adolescents reported anxiety and depression symptoms at both assessments, and parents reported family stress (family dysfunction and parenting stress) at the first assessment. Family dysfunction was not associated with future anxiety, whereas high parenting stress was. Furthermore, family dysfunction was more strongly associated with anxiety than with depression, whereas parenting stress was more strongly associated with depression. Level of parental psychopathology explained part of the association of family stress with anxiety. The associations were modest and the understanding of the origins of adolescents’ anxiety will require identifying other factors than family stress that account for more of the variance.