Developmental Pattern of Diurnal Cortisol Rhythm and Sex-Specific Associations With Psychopathological Symptoms During Pubertal Transition

Dimensions of child maltreatment and longitudinal diurnal cortisol patterns: The roles of resilience and child sex

Informed by the dimensional approach to adversity, this study disaggregated child maltreatment effects to examine how abuse versus neglect influenced cortisol at the baseline assessment and longitudinal changes in diurnal cortisol among a sample of Chinese children and adolescents (N = 312; aged 9-13 years; M age = 10.80, SD = 0.84; 67% boys). The moderating roles of resilience and sex differences in these associations were also explored. Results revealed distinct effects of abuse versus neglect on diurnal cortisol in girls, but not boys, which varied by the time scale of assessment and type of cortisol measure. Specifically, abuse was associated with girls' longitudinal changes in awakening cortisol, cortisol awakening response, and diurnal cortisol slope over one year, whereas neglect was associated with girls' awakening cortisol and cortisol awakening response at the baseline assessment. Further, resilience moderated the effects of abuse on girls' baseline awakening cortisol and longitudinal changes in diurnal cortisol slope, suggesting both the potential benefits and costs of resilience. Findings support the application of the dimensional approach to research on stress physiology and deepen our understanding of individual differences in the associations between child maltreatment and diurnal cortisol.

Parent-Child Separation and Diurnal Cortisol Rhythms Among Left-Behind Adolescents: The Moderating Role of Sex

Prior research examining parent-child separation and the hypothalamic-pituitary-adrenal (HPA) axis functioning has primarily focused on separation due to parental divorce or loss or forced migration. Less clear is the impact of parental economic migration on adolescents' HPA axis functioning. The present study fills this gap by examining diurnal cortisol patterns among left-behind adolescents who experienced separation from their migrant parents. Participants were 293 Chinese adolescents (33.4% girls, 66.21% left-behind adolescents; M_age = 10.80 years old, SD = 0.82 years). Two-level multilevel modeling was conducted to examine the associations between parent-child separation experiences and diurnal cortisol patterns. Although no significant differences were found between left-behind adolescents and their non-left-behind peers, results revealed that left-behind adolescents who experienced parent-child separation at earlier ages had more blunted diurnal cortisol slopes (usually signaling poorer mental and physical health), compared to their counterparts who experienced separation at older ages. Left-behind adolescent girls who had more adverse separation experiences exhibited smaller waking cortisol and blunted diurnal slopes; these findings were not observed among left-behind adolescent boys. Observing the association between timing of parent-child separation and adolescents' diurnal cortisol and the moderating effects of child sex, this study contributes uniquely to the developmental science of left-behind adolescents' physiological health.

ADHD symptoms and diurnal cortisol in adolescents: The importance of comorbidities

BACKGROUND

Altered regulation of diurnal cortisol has been associated with both dimensional symptoms and clinical diagnoses of attention deficit-hyperactivity disorder (ADHD). Indeed, a recent meta-analysis suggests that lower diurnal cortisol output may be a biomarker of attention deficit-hyperactivity disorder (ADHD); importantly, however, the influence of psychiatric comorbidities on this association has not been characterized. Approximately two-thirds of children with ADHD have at least one co-occurring neuropsychiatric condition, and altered HPA-axis function has been implicated in many of these conditions. Using dimensional measures of psychopathology, we examined whether comorbid symptoms influence the association of ADHD symptoms with daily cortisol output.

METHODS

138 adolescents (ages 11-15 years) completed measures of symptoms of psychopathology and provided saliva samples over two days. We analyzed whether ADHD symptoms were related to morning, afternoon, and evening cortisol, the cortisol awakening response (CAR) and cumulative daily cortisol (area under the curve with respect to ground [AUCg]) while accounting for symptoms of three psychiatric disorders that are commonly comorbid with ADHD: conduct disorder (CD), anxiety, and depression. In sensitivity analyses, we included symptoms of oppositional defiant disorder (ODD) in place of CD symptoms.

FINDINGS

After controlling for symptoms of CD, anxiety, and depression, ADHD symptoms were associated significantly with higher cumulative diurnal cortisol (AUCg), morning cortisol, and afternoon cortisol. Symptoms of CD, anxiety and depression were not associated significantly with any cortisol metrics; however, in sensitivity analyses, ODD symptoms were associated with lower AUCg and morning cortisol.

DISCUSSION

Our findings highlight the distinct influence of ADHD and externalizing symptoms on cortisol output. Further work is needed to examine the specificity of altered HPA-axis activity as a biomarker of ADHD and to elucidate whether symptoms of ADHD differ in their association with diurnal cortisol as a function of their severity.