Finally, we explored whether the association
between pubertal status and neural response to peer rejection and acceptance would differ for depressed youth and healthy controls.
To examine whether the relationship
between pubertal status and neural response to social evaluation differed for healthy youth and controls, similar whole brain regression analyses were conducted to identify areas showing group × pubertal status interaction effects.
Not exact matches
These effects were qualified by group ×
pubertal status interaction effects (P < 0.001, 30 voxels contiguity) indicating that, contrary to hypotheses, the relationship
between pubertal maturation and response to rejection in the left amygdala and caudate / sgACC was stronger among healthy controls than MDD youth.
Results showed that although the four - way interaction
between NCS, stressors, gender, and age was significant while the four - way interaction with
pubertal status was marginally significant, the interpretation of these interactions was largely similar, i.e., NCS and depressive symptoms were significantly related only in the presence of many stressors in middle to late adolescent boys (or in boys reporting a high
pubertal status).
Moderation by
pubertal status instead of age yielded slightly different results, that is, in the model with stress - reactive rumination, the relationship
between negative cognitive style and depressive symptoms was stronger in adolescents who perceived their
pubertal status as high, whereas age did not moderate this relationship.
The four - way interaction
between NCS, stressors,
pubertal status, and gender approached significance (β = −.10, p =.08), indicating that the interaction
between NCS and stressors was only significant in boys who perceived their
pubertal status as high (β =.42, p =.007).
Some support has been found for an association
between hormonal concentrations and negative affect20 - 24; however, social factors, including negative life events and their interaction with
pubertal status (but not hormonal
status), account for more of the variance in negative affect than biological factors alone.25 Early
pubertal timing and its social implications have also been postulated as an important risk factor in girls.26 - 31 Two recent studies, however, report that
pubertal status has a greater influence in predicting female depression than age32, 33 or the timing of puberty.32
Because of the marked collinearity
between age and
pubertal status, we were unable to estimate the effects of these 2 variables simultaneously.
Thus, we controlled for three level 1 variables (age,
pubertal status, and treatment delivery method), two level 2 variables (baseline social
status and baseline BMI), and the interaction
between age and BMI in cross-sectional multilevel models.