SLEEP 2011 Abstract Supplement

B. Clinical Sleep Science IX. Psychiatric and Behavioral Disorders and Sleep
ing after sleep with subjects seated and eyes closed. The intervening
sleep was recorded. Analyses used unpaired t-tests and Pearson correlations.
Results: When examining global EEG power in the evening and morning,
no differences were found between controls and MDD subjects.
However, MDD subjects had a weaker low frequency power (2-8Hz)
frontocentrally, both in the evening and morning. Next we examined
the decline in waking power from evening to morning. Control subjects
showed an overnight decline in low (1.5-7.5Hz) and high (9.5-37Hz)
frequencies, whereas MDD subjects did not show a decline below 8 Hz,
although they did decline in the 10-33Hz range. In controls, overnight
change in waking theta and alpha power correlated to sleep SWA in the
frontocentral region. In contrast, MDD subjects did not exhibit global or
regional correlations of changes in waking theta and alpha power with
sleep SWA.
Conclusion: This study suggests that changes in waking EEG traces in
healthy subjects that correlate with sleep homeostatic decline are altered
in MDD. Further studies are needed to better assess altered sleep-wake
homeostasis in depression and to determine if these findings are specific
to subtypes of depression.
Support (If Any): This research was funded by the National Institute of
Mental Health (5P20MH077967 to GT and RB, F30MH082601 to EL)
0742
OVERNIGHT CHANGES IN AUDITORY EVOKED
POTENTIAL AMPLITUDE REFLECT ALTERED SLEEP
HOMEOSTASIS IN MAJOR DEPRESSION
Goldstein MR 1 , Sarasso S 1 , Landsness EC 1 , Plante DT 1 , Hulse BK 2 ,
Laing HK 1 , Tononi G 1 , Benca R 1
1
Department of Psychiatry, University of Wisconsin School of
Medicine and Public Health, Madison, WI, USA, 2 Department of
Biology, California Institute of Technology, Pasadena, CA, USA
Introduction: Previous research has demonstrated that waking auditory
evoked potential (AEP) amplitude declines after a night of sleep and that
the overnight reduction in AEP amplitude correlates with the amount of
sleep slow wave activity (SWA), suggesting that changes in the AEP
waveform may reflect a homeostatic process related to sleep. Because
major depressive disorder (MDD) may involve altered sleep homeostasis,
we investigated overnight changes in AEPs and their relation to
sleep SWA in MDD and matched controls.
Methods: As part of a larger study on sleep homeostasis in depression,
pre- and post-sleep single-tone, waking AEPs and all-night sleep recordings
with 256-channel high-density EEG were analyzed for 11 righthanded,
non-medicated MDD participants (8 female) and 11 age- and
sex-matched controls. Overnight changes in amplitude and latency for
N1 and P2 components were analyzed with paired t-tests for each group,
while their relationships with sleep spectral power were calculated with
a Pearson correlation.
Results: A significant pre- to post-sleep decline in N1 amplitude was
observed for healthy controls (p < .05), but not for the MDD group.
Moreover, the overnight change in N1 amplitude correlated with sleep
SWA (1-4.5Hz) only for the control group (p < .02); more SWA predicted
a greater reduction in amplitude. No significant differences before
and after sleep were detected for P2 amplitude, N1 latency, or P2 latency
for either group.
Conclusion: These results support the notion that the overnight decline
in N1 amplitude may reflect a sleep-related homeostatic process and
suggest that MDD involves altered regulation of such homeostasis. Importantly,
these findings indicate that single-tone AEPs, combined with
high-density EEG, may provide a useful measure for investigating sleep
homeostasis in depression. Subsequent research is required to corroborate
these findings, and to examine the potential utility of AEPs in categorizing
MDD in terms of subgroups and predicting treatment response.
Support (If Any): This research was funded by the National Institute
of Mental Health (5P20MH077967 to GT and RB, and F30MH082601
to EL).
0743
EFFECTS OF EARLY AND LATE PARTIAL SLEEP
DEPRIVATION ON SLEEP AND SLOW-WAVE ACTIVITY
(SWA) IN MAJOR DEPRESSIVE DISORDER
Arnedt J, Swanson L, Bertram H, Mooney A, Dopp R, Hoffmann RF,
Armitage R
Psychiatry, University of Michigan, Ann Arbor, MI, USA
Introduction: Acute total and partial sleep deprivation improve mood
in more than half of major depressive disorder (MDD) patients, but relapse
is common following recovery sleep and its practicality is limited
in outpatient settings. We compared sleep PSG and SWA in MDD participants
assigned to a more modest repeated early or late partial sleep
deprivation (6 hours TIB) vs. no sleep deprivation (8 hours TIB) in conjunction
with antidepressant medication.
Methods: Twenty-two subjects meeting DSM-IV criteria for MDD
(25.2 ± 6.7 years of age, 9 women, baseline HAMD-17 score 20.2 ± 1.8)
have participated to date. Subjects received 8 weeks of fluoxetine 20-40
mg and were randomized to two weeks of no sleep deprivation (NSD,
n=7), early partial sleep deprivation (E-PSD, 2-hour delay of bedtime,
n=7) or late partial sleep deprivation (L-PSD, 2-hour advance of rise
time, n=8). Following an 8-hour at-home sleep schedule, subjects underwent
PSG at baseline, on the first and last experimental nights, and on
the first recovery night (8 hours TIB).
Results: No group differences were found on baseline sleep variables.
Total sleep time was reduced in the E-PSD and L-PSD groups compared
to NSD on experimental nights vs. baseline (p < .001). Stage N3%
increased in the E-PSD group and decreased in the L-PSD and NSD
groups (p < .03). REM latency and Stage N1% were elevated and SWA
power was decreased on the last experimental night compared to baseline
and the first experimental night (p < .001). REM% increased during
recovery sleep in the L-PSD group while Stage N2% increased in the
E-PSD and NSD groups.
Conclusion: The sleep manipulations increased SWS and SWA in the
E-PSD group, while fluoxetine increased Stage N1 and prolonged REM
latency in all three groups. We are evaluating how the sleep manipulations
combined with fluoxetine influence self- and clinician-rated mood.
Support (If Any): NIH R01 MH077690 (JT Arnedt)
0744
OBJECTIVE VS. SUBJECTIVE MEASUREMENTS OF SLEEP
IN DEPRESSED INSOMNIACS: FIRST NIGHT EFFECT OR
REVERSE FIRST NIGHT EFFECT?
McCall C 1 , Bowes RC 2,3 , McCall W 4
1
Wake Forest University School of Medicine, Winston-Salem, NC,
USA, 2 Department of Clinical Research, Campbell University School
of Pharmacy, Buies Creek, NC, USA, 3 Consultant, Philips Respironics,
Fuquay Varina, NC, USA, 4 Department of Psychiatry and Behavioral
Medicine, Wake Forest University Health Sciences, Winston-Salem,
NC, USA
Introduction: Many individuals experience worse sleep during their
first night in a sleep laboratory compared to succeeding laboratory
nights. This “first night effect” is typically characterized by increased
sleep onset and REM latency, less REM stage sleep, and lower sleep
efficiency. In contrast, other studies have observed a “reverse” first night
effect, in which individuals sleep better the first night at the laboratory
compared to later nights. Studies investigating laboratory adaptation effects
have typically focused on comparing the first night in the laboratory
with successive nights in the same environment. This study compared
sleep in the laboratory with sleep at home, before and after laboratory
monitoring, in depressed insomniacs undergoing treatment.
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SLEEP, Volume 34, Abstract Supplement, 2011