Examining the effects of sleep delay on depressed males and females and healthy controls

Abstract

SUMMARYIndividuals with major depressive disorder typically exhibit sleep electroencephalograpy abnormalities which have been shown to vary by sex. Recent research has shown that depressed males display deficits in slow wave sleep and delta electroencephalograph (EEG) activity that are not apparent in depressed females. This may suggest that males and females with depression vary with respect to their homeostatic regulation of sleep. Utilizing archival data, the present study examined the effects of a 3-h sleep delay, which represents a mild sleep challenge, on slow wave activity in healthy controls and individuals with depression. All participants slept in the laboratory for three sequential nights. On the third night in the laboratory, the participants' bedtime was delayed by 3 h. Slow wave activity was calculated utilizing power spectral analysis and compared across groups. Following the sleep delay, males with depression exhibited the lowest slow wave activity compared to all other groups. These results may suggest that males with depression are at a greater risk for homeostatic dysregulation than females, and may require specialized intervention. IN TROD UCTI ONSleep disturbance is one of the central symptoms reported by most individuals with major depressive disorder (MDD; Mendlewicz, 2009). Years of research looking at differences in sleep between healthy subjects and those diagnosed with MDD have greatly increased our understanding of the qualitative difference in sleep in those with MDD. With regard to the most common differences in visually scored sleep variables, research has shown consistently that individuals with MDD have more proportionate time awake, a measure of sleep efficiency, shorter time to enter REM sleep (REM latency), greater amount of REM sleep, increased amounts of rapid eye movements (REM density) and decreases in slow wave sleep compared to healthy controls. Understanding these qualitative differences has been an essential first step; however, newer methodology, including quantitative electroencephalograph (EEG) analysis, may allow us to assess more clearly the differences in sleep regulation in MDD. Borb ely and Wirz-Justice (1982) suggested that the sleep disturbances occurring in individuals with MDD, including delayed sleep onset and difficulty maintaining sleep, were a result of a reduced drive for sleep (process S). This model also suggests that those with MDD would present reduced slow wave sleep during the first portion of the night, when slow wave activity is typically at its highest. Kupfer et al. (1986) demonstrated that there was indeed a reduction in slow wave EEG activity in NREM sleep (SWA) in those with MDD; however, they also noted that there was only a very small relationship between time awake and reduced delta activity in those with MDD. Utilizing quantitative EEG analyses, Armitage et al. (1992Armitage et al. ( , 1995Armitage et al. ( , 1997Armitage et al. ( , 2000a have also shown that individuals with MDD exhibit an abnormal distribution of SWA across the nigh...

Neurophysiological correlates of suicidal ideation in major depressive disorder: Hyperarousal during sleep

“…These results also lend preliminary support for the hypothesis that suicide risk is associated with reduced delta activity beyond the decrease in delta activity typical of depression (Armitage, 1995; Armitage et al, 2000a, 2000b; Cheng et al, 2015; Goldschmied et al, 2014; Kupfer et al, 1986; Lotrich and Germain, 2015). Although no differences were observed for absolute whole night delta activity, relative delta activity was reduced in participants with high suicidal ideation and MDD, controlling for depression symptoms.…”

“…Sleep electroencephalography (EEG) has been identified as a tool to identify potential biomarkers for disorders closely related to suicide such as major depressive disorder (Armitage et al, 2006; Benca et al, 1992; Cheng et al, 2015; Goldschmied et al, 2014; Steiger and Kimura, 2010). Further, findings from a meta-analysis indicate that sleep EEG abnormalities may also represent a transdiagnostic psychophysiological mechanism that cuts across disorders (Baglioni et al, 2016).…”

“…Abnormal delta activity has consistently been observed in MDD (Armitage, 1995; Armitage et al, 2000a, 2000b; Cheng et al, 2015; Goldschmied et al, 2014; Kupfer et al, 1986; Lotrich and Germain, 2015), as well as a range of other disorders including insomnia (Buysse et al, 2008; Dijk, 2010; Merica et al, 1998), alcohol dependence (Brower et al, 2011), and schizophrenia (Hoffmann et al, 2000). Decreased delta activity may also be further compounded by the presence of fast frequency activity during periods of sleep that typically contain slow frequency delta activity.…”

Reduction in delta activity predicted improved negative affect in Major Depressive Disorder

“…Delta power was averaged across all electrode sites from all the non-REM periods. Details regarding the quantification of delta activity has been previously described (see Goldschmied et al, 2014).…”

“…While several studies have indicated that abnormalities in slow-wave sleep are characteristic of those with depression (Beersma and Van den Hoofdakker, 1992;Armitage and Hoffmann, 2001;Goldschmied et al, 2014), the specific relationship between slow-wave abnormalities and the various dimensions in the phenomenology of depression is still unclear. Conceptualizing and understanding depression utilizing a dimensional approach is increasingly important due to the heterogeneity in symptom presentation between individuals.…”