Premorbid polysomnographic signs in depressed adolescents: A reanalysis ofEEG sleep after longitudinal follow-up in adulthood

Background: This is a report of a clinical follow-up study (10-15 years lat er as young adults) of adolescent major depressives and normal control subj ects. Polysomnographic data were obtained during the original study period when the subjects were adolescent (time 1), With clinical follow-lip (time 2) assessments in hand, our objective was to ascertain whether there were a ny premorbid polysomnographic signs associated with depression during adole scence. Methods: Based upon initial (during adolescence) and follow-lip clinical as sessments las adults), new subject groupings were generated: depression-fre e normal subjects and original normal subjects who experienced a depressive episode during the follow-up period (latent depressives). Suicidality and recurrence of depression were also examined Multivariate analysis of covari ance was used to analyze group differences in sleep measures and logistic r egression for predicting three outcomes: lifetime depression, lifetime suic idality, and recurrence. Results: Comparison of the depression-free normal subjects, the latent depr essives, and the original major depressives revealed significant difference s for sleep latency and sleep period time. Comparing all lifetime depressiv es (original major depressives and the latent depressives) to depression-fr ee normal subjects revealed significantly more stages 3 and 4 combined (ST3 4) sleep and greater sleep period times among the depressives. An analysis involving the presence or absence of suicidality revealed no overall signif icant differences between the groups. Comparison of the lifetime depressive s grouped by nonrecurrent and recurrent depressive course to the depression -free normal subjects revealed significant difference for sleep period rime . Using logistic regression, we found that a longer sleep latency and sleep period time significantly predicted lifetime depression. Gender, ST34 slee p, and an interaction term for ST34 sleep and REM latency significantly pre dicted lifetime suicidality, Conclusions: There was evidence of premorbid sheep abnormalities during ado lescence. A general pattern of sleep disruption around sleep onset and duri ng the first 100 min of the sleep period and overall sleep was evident amon g the major and lifetime depressives, involving sleep latency (initial inso mnia), sleep period time (hypersomnia), REM latency, and slow-wave sleep. T his adds to the body of literature that highlights the importance of the fi rst 100 min of the sleep period in depression. (C) 2001 Society of Biologic al Psychiatry.