Sleep regularity, circadian rhythms, and chronotype as mechanisms of risk for affective dysregulation in female adolescents

Abstract

In a sample of early post-menarchal female adolescents, this study examined sleep regularity in relation to depression symptoms, circadian rhythms, and chronotype preference. Sixty-six female adolescents, aged 11–14 and within fifteen months post-menarche, completed a one week sleep and circadian rhythm assessment involving self-reported sleep behaviors, 24-h sleep monitoring using wrist actigraphy, and serial cortisol and 6-sulfatoxymelatonin collections for four days. Sleep regularity was operationalized as the probability of being in the same wake/ sleep state at any two timepoints 24 h apart (i.e., sleep regularity index (SRI)). Reduced SRI was associated with higher depressive symptoms (F [1,273] = 18.65, p =