Delta sleep EEG in depressed adolescent females and healthy controls

Background: Quantitative EEG studies have identified a number of sleep abno rmalities in adults with major depressive disorders (MDD), including a redu ction in the amplitude of delta activity during NREM;I sleep. To date, thes e methodologies have not been used in early onset R-IDD. Methods: Delta act ivity during NREM sleep was compared in eight symptomatic but unmedicated a dolescent females with MDD and eight age- and gender-matched healthy contro ls. Results: The depressed group showed significantly lower delta amplitude and power in the first NREM sleep period. By contrast, standard sleep arch itecture did not differentiate between groups. Limitations: Given the sampl e size, this study is best viewed as tentative. In addition, it has yet to be determined whether adolescent males with MDD also show delta sleep abnor malities. Further, failure to find between-group differences in REM latency or other macroarchitectural measures may be due to the small sample size. Conclusions: The findings of this study underscore the utility of quantitat ive sleep EEG techniques in early onset MDD. The results of the present stu dy do, however, diverge from reports in adults with MDD, where delta abnorm alities are more prevalent in men. Such findings suggest that the maturatio nal time course of sleep EEG disturbances may differ for males and females with depression. Early emergence of delta abnormalities in depression may b e of relevance to clinical course of illness. (C) 2001 Elsevier Science B.V . All rights reserved.