Date Published: March 9, 2018
Publisher: Public Library of Science
Author(s): Qingyun Lu, Fada Pan, Lingling Ren, Jing Xiao, Fangbiao Tao, Erica van den Akker.
Although numerous studies have described the relationship between HPA axis dysregulation and internalizing symptoms among adolescents, research using hair cortisol concentrations in pre- and young adolescent samples has not been reported. We investigated the association of self-reported internalizing symptoms with cortisol concertration in hair among pre- and young adolescents aged 10–12 years. Forty-six boys and 39 girls supplied a hair sample of at least 3 cm in length for an analysis of this period (3 months) cortisol excretion. Saliva cortisol reactivity to the Trier Social Stress Test for Children (TSST-C) also was assessed. The study found a positive association between ratings of depressive symptoms and cumulative levels of hair cortisol only in boys. Furthermore, higher ratings of anxiety symptoms were associated with lower hair cortisol concertration and lower saliva cortisol reactivity among girls. This study provides the first evidence for the notion that depressive symptoms in boys are associated with long-term cortisol concertration in hair, whereas anxiety symptoms in girls are associated with HPA-axis hypoactivity, when hair cortisol concentrations and saliva cortisol reactivity to acute stress are assessed concurrently.
Internalizing symptoms in children and adolescents, such as non-clinical depression and anxiety traits, are key health issues inchildhood and adolescence. Brady and Kendall ,who performed a literature review of internalizing disorders in children and adolescents, estimated that 15.9–61.9% of children and adolescents have anxiety and depression disorders. Early emerging internalizing symptoms predict later internalizing disorders . The hypothalamic–pituitary–adrenal (HPA) axis, which is acentral component of the body’s neuroendocrine response to stress, is thought to play a central role in the pathophysiology of depressive and anxiety disorders.
Sociodemographic and anthropometric characteristics, internalizing symptoms, AUCi in saliva, and cortisol level in hair of all participants are shown in Table 1. Univariate liner regression on hair cortisol levels or saliva cortisol reactivity (AUCi) were presented for sex, age, BMI-Z, school-level, Tanner-stage, parental educational level, family income, and internalizing symptoms levels (Table 2). Hair cortisol level was higher in girls than in boys (p = 0.008). Lower family income was associated with higher hair cortisol levels (p = 0.013). Mother’s education level was positive associated to hair cortisol levels (p = 0.008). The scores of CDI were positive associated with cortisol level in hair, but the association was not significantly (p = 0.060). Multivariate liner regression analysis estimated for the indicators with hair cortisol or saliva cortisol logAUCi were presented in Table 2. The significant relative gender*CDI score interaction terms (β = -1.168, p = 0.012) indicated that the positive association between hair cortisol and depressive symptoms was stronger among boys, for whom being depression symptoms was less common. The scores of SCARED were not significantly related to hair cotisol level (p = 0.257) (Table 2). However, the significant relative sex* SCARED score interaction terms indicated that the negative association between hair cortisol and anxiety symptoms was stronger among girls (β = -1.129, p = 0.002). We also found a significant negative association of saliva cortisol AUCi with family income in univariate liner regression (p = 0.033). In multivariate liner regression, the significant relative sex* SCARED score interaction terms on saliva cortisol AUCi (β = -1.458, p = 0.021). No associations between saliva cortisol and CDI score were found with the linear regression model (Table 2).
To our knowledge, this is one of the first studies to investigate the association between ratings of self-reported internalizing symptoms and HPA-axis activity, which were assessed by two different methodologies—long-term cortisol concentrations in the hair and cortisol reactivity to acute stress in the saliva of pre- and young adolescents. This study found a positive association between ratings of depressive symptoms and cumulative hair cortisol but not saliva cortisol activity among boys. Furthermore, this study found a negative association of anxiety symptoms levels with cumulative hair cortisol and acute cortisol reactivity in the saliva of girls.
In summary, this study is a first step in research on the association between self-reported internalizing symptoms and hair cortisol concentrations and cortisol reactivity in saliva in pre- and young adolescent samples aged 10–12 year-old. This study found a positive association between ratings of current depressive symptoms and cumulative hair cortisol levels only in boys. Furthermore, higher ratings of anxiety symptoms were associated with lower long-term hair cortisol excretion and lower saliva cortisol reactivity under acute stress among girls aged 10–12 years. This provides the first evidence for the notion that depressive symptoms in boys are associated with long-term cortisol concertration, whereas anxiety symptoms in girls are associated with HPA-axis hypoactivity, when long-term cortisol concentration and acute cortisol reactivity are assessed concurrently.