Ecological Study of Sleep Disruptionin PTSD

A Pilot Study

ANNE GERMAIN, MARTICA HALL, M. KATHERINE SHEAR,ERIC A. NOFZINGER, AND DANIEL J. BUYSSE

Department of Psychiatry, University of Pittsburgh School of Medicine,Pittsburgh, Pennsylvania 15213, USA

ABSTRACT: Laboratory-based sleep studies have yielded inconsistent re-sults regarding the presence and nature of objective sleep anomalies inposttraumatic stress disorder (PTSD). This pilot study aimed at assessingsleep in adult crime victims with PTSD by using in-home polysomnog-raphy. Compared to healthy archival subjects, PTSD subjects showedlonger sleep latency, reduced total sleep time, and increased duration ofnocturnal awakening. Quantitative electroencephalography (EEG) mea-sures of delta and beta activity also differed in PTSD and healthy sub-jects. These preliminary findings suggest that ambulatory methods cancapture objective signs of sleep disruption, and corroborate subjectivecomplaints of disrupted sleep in PTSD.

KEYWORDS: PTSD; sleep; in-home polysomnography

INTRODUCTION

Sleep disturbances are a core feature of posttraumatic stress disorder(PTSD). However, laboratory-based studies have not consistently corrobo-rated subjective complaints that characterize PTSD.1 Studies that have quan-titative electroencephalography (EEG) measures have reported elevated in-dices central arousal during sleep in PTSD subjects.2,3 The goals of this pilotstudy was to investigate sleep in PTSD by using in-home polysomnographic(PSG) recordings, and to explore whether refined quantitative EEG measuresdiffer in PTSD versus archival healthy control subjects equated for age andsex.

Address for correspondence: Anne Germain, Ph.D., Department of Psychiatry, University of Pitts-burgh School of Medicine, 3811 O’Hara Street, Room E-1124, Pittsburgh, PA 15213. Voice: 412-246-6436; fax: 412-246-5300.

e-mail: germaina@upmc.edu

Ann. N.Y. Acad. Sci. 1071: 438–441 (2006). C© 2006 New York Academy of Sciences.doi: 10.1196/annals.1364.038

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GERMAIN et al.: ECOLOGICAL STUDY OF SLEEP IN PTSD 439

METHODS

The University of Pittsburgh Internal Review Board approved the studies.Ten adult victims of violent crime with PTSD (Mean age: 34.6 ± 6.3 years; 3men) were recruited via advertisement flyers and from the Pittsburgh Center forVictims of Violent Crimes. All met diagnostic criteria for current PTSD, andendorsed symptoms of poor sleep quality. All completed two consecutive nightsof in-home sleep studies. Sleep parameters recorded on night 2 were comparedto sleep data collected in two healthy groups. The first group included fivesubjects (Mean age = 34.0 ± 5.1 years; 2 men) who participated in a largerstudy on chronic stress and sleep (MH01554), and who completed similarin-home sleep recording procedures (HOME group). The second included 10archival healthy subjects (Age = 36.9 ± 11.1 years; 3 men) who slept in thelaboratory (LAB group) as part of other studies conducted at the Universityof Pittsburgh Clinical Neuroscience Research Center (MH24652; MH66227;MH61566).

Visually scored sleep parameters and quantitative EEG measures collectedon night 2 were compared between groups. Given the small sample sizes,Cohen’s d effect sizes were calculated to assess the magnitude of group dif-ferences.4 Small, medium, and large effect sizes are indicated by d-values of0.20, 0.50, and 0.80, respectively. Positive Cohen’s d coefficients reflect groupdifferences in the expected direction, whereas negative Cohen’s d coefficientsreflect group differences in the unexpected directions.

RESULTS

TABLE 1 presents mean values for visually scored and quantitative EEG sleepparameters in the PTSD compared to the two healthy samples. Medium tolarge effect sizes were observed for all visually scored sleep parameters. ThePTSD group showed increase in beta activity compared to the LAB group,and an unexpected increase in delta activity compared to both comparisongroups.

CONCLUSIONS

These preliminary findings suggest that ambulatory methods can capturePSG-assessed indices of disturbed sleep, and corroborate subjective sleep com-plaints. The observed increased beta activity in the PTSD group may reflectheightened physiological arousal during sleep. Given that delta power is an in-dex of sleep pressure, the observed increase in delta activity may be a correlateof chronic disruption in PTSD.

440 ANNALS NEW YORK ACADEMY OF SCIENCES

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ACKNOWLEDGMENTS

This work was supported by the Pittsburgh Mind Body Center PittsburghMind-Body Center funded through NIH grants HL65111 and HL65112, theCanadian Institutes of Health Research, and the National Institute of Health(AG00972, RR00056; MH01554; MH66227, MH61566 MH24652).

REFERENCES

1. PILLAR, G., A. MALHOTRA & P. LAVIE. 2000. Post-traumatic stress disorder andsleep-what a nightmare! Sleep Med. Rev. 4: 183–200.

2. NEYLAN, T.C. et al. 2003. Delta sleep response to metyrapone in post-traumaticstress disorder. Neuropsychopharmacology 28: 1666–1676.

3. WOODWARD, S.H., M.M. MURBURG & D.L. BLIWISE. 2000. PTSD-related hyper-arousal assessed during sleep. Physiol. Behav. 70: 197–203.

4. COHEN, J. 1988. Statistical Power Analysis for the Behavioral Sciences, 2nd ed.Lawrence Earlbaum Associates. Hillsdale, NJ.