CLINICAL REVIEW Sleep disturbances in sexual abuse victims: A systematic review Iris M. Steine a, * , Allison G. Harvey b, c , John H. Krystal d, e , Anne M. Milde f, i , Janne Grønli f, g, j , Bjørn Bjorvatn g, h, k , Inger H. Nordhus b, g , Jarle Eid a, l , Ståle Pallesen a, g, m a Department of Psychosocial Science, University of Bergen, Christiesgate 12, 5015 Bergen, Norway b Department of Clinical Psychology, University of Bergen, Christiesgate 12, 5015 Bergen, Norway c Department of Psychology, University of California, Berkeley, USA d Clinical Neuroscience Division, VA National Center for PTSD, VA Connecticut Healthcare System, West Haven, CT, USA e Department of Psychiatry, Yale University School of Medicine, Suite #901, 300 George St., New Haven, CT 06511, USA f Department of Biological and Medical Psychology, University of Bergen, Jonas Liesvei 91, 5009 Bergen, Norway g Norwegian Competence Center of Sleep Disorders, Haukeland University Hospital, Jonas Lies vei 91, 5009 Bergen, Norway h Department of Public Health and Primary Health Care, University of Bergen, Kalfarveien 31, 5018 Bergen, Norway article info Article history: Received 15 November 2010 Received in revised form 31 January 2011 Accepted 31 January 2011 Available online 19 May 2011 Keywords: Sexual abuse Child sexual abuse Incest Sleep disturbance Insomnia Nightmare Sleep paralysis summary An impressive body of research has investigated whether sexual abuse is associated with sleep distur- bances. Across studies there are considerable differences in methods and results. The aim of this paper was to conduct the first systematic review of this area, as well as to clarify existing results and to provide guidelines for future research. We conducted searches in the electronic databases PsycINFO and PubMed up until October 2010 for studies on sleep disturbances in sexually abused samples. Thirty-two studies fulfilled the inclusion criteria (reported empirical data, included sexually abused subjects, employed some form of sleep measurement, English language and published in peer reviewed journals). Across the studies included, sleep disturbances were widespread and more prevalent in sexually abused subjects as compared to in non-abused samples. Symptoms reported more frequently by sexually abused samples included nightmare related distress, sleep paralysis, nightly awakenings, restless sleep, and tiredness. Results were divergent with regards to sleep onset difficulties, nightmare frequency, nocturnal activity, sleep efficiency, and concerning the proportion of each sample reporting sleep disturbances as such. Potential sources of these divergences are examined. Several methodological weaknesses were identified in the included studies. In order to overcome limitations, future researchers are advised to use stan- dardized and objective measurements of sleep, follow-up or longitudinal designs, representative pop- ulation samples, large sample sizes, adequate comparison groups, as well as comparison groups with other trauma experiences. Ó 2011 Elsevier Ltd. All rights reserved. Introduction Sleep disturbances and traumatic symptomatology have long been associated with the diagnostic and statistical manual of mental disorders. 4th edition (DSM-IV-TR) criteria for acute and posttraumatic stress disorder, which lists insomnia and nightmares as core symptoms. 1 Moreover, several studies have documented an association between various sleep disturbances and traumatized individuals, with differences emerging as a result of specific trauma types. 2 Over the past decade an impressive body of literature has emerged investigating the extent and nature of sleep disturbance associated with sexual abuse. This is an important field of study given the known prevalence of sexual abuse 3 as well as the adverse impact of sleep disturbance on health and emotional functioning. 4e11 Sexual abuse is defined as any sexual act to which the victim did not consent, could not consent, or was pressured or manipulated into consenting. The sexual acts in question may comprise a wide range of behaviors, such as touching and fondling, indecent * Corresponding author. Tel.: þ47 98 47 63 72; fax: þ47 55 58 98 79. E-mail addresses: iris.steine@gmail.com (I.M. Steine), aharvey@berkeley.edu (A. G. Harvey), john.krystal@yale.edu (J.H. Krystal), anne.milde@psybp.uib.no (A.M. Milde), janne.gronli@uib.no (J. Grønli), bjorn.bjorvatn@isf.uib.no (B. Bjorvatn), inger.nordhus@psykp.uib.no (I.H. Nordhus), jarle.eid@psysp.uib.no (J. Eid), staale. pallesen@psysp.uib.no (S. Pallesen). i Tel.: þ47 55586231; fax: þ47 55589872. j Tel.: þ47 55586003. k Tel.: þ4755586088. l Tel.: þ47 55589188. m Tel.: þ47 55588842. Contents lists available at ScienceDirect Sleep Medicine Reviews journal homepage: www.elsevier.com/locate/smrv 1087-0792/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.smrv.2011.01.006 Sleep Medicine Reviews 16 (2012) 15e25