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Latent classes of childhood trauma exposure predict the development of behavioral health outcomes in adolescence and young adulthood E. D. Ballard 1*, K. Van Eck 2,3, R. J. Musci 2, S. R. Hart 4, C. L. Storr 2,5, N. Breslau 6and H. C. Wilcox 2,7 1National Institute of Mental Health, Experimental and Pathophysiology Branch, Bethesda, MD, USA2Department of Mental Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA3Division of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA4Child Development Department, California State University, Chico, CA, USA5Department of Family and Community Health, School of Nursing, University of Maryland, Baltimore, Baltimore, MD, USA6Department of Epidemiology and Biostatistics, Michigan State University, East Lansing, MI, USA7Child and Adolescent Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA Background.To develop latent classes of exposure to traumatic experiences before the age of 13 years in an urban com- munity sample and to use these latent classes to predict the development of negative behavioral outcomes in adolescence and young adulthood.

Method.A total of 1815 participants in an epidemiologically based, randomizedﬁeld trial as children completed com- prehensive psychiatric assessments as young adults. Reported experiences of nine traumatic experiences before age 13 years were used in a latent class analysis to create latent proﬁles of traumatic experiences. Latent classes were used to predict psychiatric outcomes at age513 years, criminal convictions, physical health problems and traumatic experiences reported in young adulthood.

Results.Three latent classes of childhood traumatic experiences were supported by the data. One class (8% of sample), primarily female, was characterized by experiences of sexual assault and reported signiﬁcantly higher rates of a range of psychiatric outcomes by young adulthood. Another class (8%), primarily male, was characterized by experiences of vio- lence exposure and reported higher levels of antisocial personality disorder and post-traumatic stress. Theﬁnal class (84%) reported low levels of childhood traumatic experiences. Parental psychopathology was related to membership in the sexual assault group.

Conclusions.Classes of childhood traumatic experiences predict speciﬁc psychiatric and behavioral outcomes in adoles- cence and young adulthood. The long-term adverse effects of childhood traumas are primarily concentrated in victims of sexual and non-sexual violence. Gender emerged as a key covariate in the classes of trauma exposure and outcomes.

Received 3 April 2015; Revised 16 June 2015; Accepted 16 June 2015; First published online 7 July 2015 Key words:Childhood adverse experiences, latent class analysis, trauma, young adulthood.

Exposure to childhood trauma is associated with a host of negative outcomes, including, but not limited to, post-traumatic stress disorder (PTSD). As demon- strated in investigations such as the Adverse Childhood Experiences (ACE) study (Felittiet al.

1998; Andaet al.2006; Dubeet al.2009), childhood ad- versity has been associated with adult outcomes, such as suicide, depression, alcohol use, drug use, and phys- ical consequences, such as autoimmune disorders. Theterm‘toxic stress’has been used to describe multiple chronic stressors in childhood, including abuse, neg- lect, parental substance use, or parental depression, which may lead to changes in learning, behavior, and physiology that have an impact throughout adult- hood (Garner & Shonkoff,2012; Shonkoff & Garner, 2012). Childhood maltreatment has been suggested as a neurobiologically distinct subtype or‘ecophenotype,’ due to the earlier onset of symptoms, symptom sever- ity, co-morbidity, and poor treatment response asso- ciated with it (Teicher & Samson,2013). Changes in reactivity in the hypothalamic–pituitary–adrenal (HPA) axis, reduced hippocampal volume and amyg- dala reactivity as well as epigenetic changes, such as DNA methylation, have been suggested as possible mechanisms for this relationship (Szyf,2011; Teicher * Address for correspondence: E. D. Ballard, Ph.D., National Institute of Mental Health, Experimental and Pathophysiology Branch, Building 10, CRC Room 7-3345, 10 Center Drive, MSC 1282, Bethesda, MD 20892, USA.

(Email: [email protected]) Psychological Medicine(2015),45, 3305–3316. © Cambridge University Press 2015 doi:10.1017/S0033291715001300 ORIGINAL ARTICLEhttps:/www.cambridge.org/core/terms . https://doi.org/10.1017/S0033291715001300Downloaded from https:/www.cambridge.org/core . George Fox University , on 20 Mar 2017 at 16:34:28 , subject to the Cambridge Core terms of use, available at & Samson,2013; Anackeret al.2014). From a develop- mental perspective, diagnoses such as depression, PTSD and substance use disorder often have an onset in adolescence to early adulthood (Kessleret al.

2005). Childhood traumatic experiences may lead to changes in brain development, as well as gene expres- sion, which inﬂuence the early development of behav- ior problems and onset of psychiatric symptoms. Thus, many mental and physical health diagnoses may have their roots in childhood experiences.

Due to the wealth of data on the negative impact of childhood traumatic experiences and the potential im- pact of stress on the developing brain, research in this area may beneﬁt from isolating childhood trauma from trauma that occurs in adolescence or adulthood. It has been suggested that traumatic experiences in child- hood lead to a more diverse array of PTSD symptoms than traumatic experiences that occur in adulthood (Cloitreet al.2009). Epigenetic changes, such as DNA methylation, may depend on when in life the adverse experience occurs, as PTSD from a childhood trauma has a different epigenetic proﬁle than PTSD from a trauma during adulthood (Mehtaet al.2013). Last, there is some evidence that childhood traumatic experiences early in life may increase the risk of trauma exposure later in adulthood (Aciernoet al.1999), the cumulative effect of which may have an impact on later outcomes in adulthood. Consequently, limiting the focus of analysis to the critical window of pre- adolescent experiences may help to tease apart poten- tial inﬂuences on later development.

As deﬁned by the DSM-5 diagnostic criteria of PTSD, trauma encompasses a range of experiences, from being directly assaulted to witnessing a traumatic event to hearing about a traumatic event experienced by a friend or family member (APA,2013). Types of trauma exposures may have an impact on the develop- ment of negative outcomes, with experiences such as assaultive trauma conferring higher risk for PTSD and other psychiatric outcomes than other trauma types (Breslauet al.1998a; Chung & Breslau,2008; Wilcoxet al.2009). At the same time, the accumulation of multiple smaller traumatic and adverse experiences may also impact mental and physical health (Odgers & Jaffee,2013). Exposure to one traumatic event in child- hood may increase the likelihood of exposure to other childhood traumatic experiences, suggesting that childhood traumatic events are often interrelated (Donget al.2004). In addition, family history of psy- chopathology or substance use could create a familial environment in which multiple types of trauma are more likely to occur (Walshet al.2002,2003). As a re- sult, traumatic experiences may not occur in isolation and a pattern of multiple traumatic experiences across the same time period may be involved.The current project aimed to study the effect of child- hood trauma exposures before the age of 13 years on psychiatric (e.g. suicidal behavior, substance abuse), criminal, and physical health outcomes by young adulthood. A latent class analysis (LCA) approach per- mitted the examination of how different types of trau- matic exposures typically cluster across childhood, in order to identify speciﬁc demographic and clinical proﬁles of childhood traumatic experiences. These classes can identify those individuals with childhood trauma who go onto develop negative outcomes in young adulthood, which will have implications for screening, intervention and prevention efforts. A wide breadth of negative outcomes in adolescence and young adulthood was investigated for a transdiag- nostic perspective on the relationship of childhood trauma and psychiatric outcomes, as well as the poten- tial impact of trauma on medical or behavioral out- comes. We used data from a community-based sample of children from an urban environment fol- lowed from childhood into young adulthood.

Traumatic experiences were limited to those reported to occur before the age of 13 years in order to obtain a depiction of childhood adversity. Development of these latent classes can inform future genetic, epigenetic, and neurobiological studies of how speciﬁc types of childhood traumatic experiences lead to distinct nega- tive outcomes in young adulthood.

Method Participants and procedures The sample consisted of 2311 participants initially recruited inﬁrst grade as part of an epidemiologically based, randomizedﬁeld trial of two school-based pre- ventive interventions, whose immediate targets were reading achievement and aggressive, disruptive beha- viors (Kellamet al.1991; Kellamet al.2008). Nineteen elementary schools withinﬁve urban areas were ran- domly assigned within each urban area to a control condition or one of two intervention conditions pro- vided only duringﬁrst and second grade. The inter- vention conditions were the Good Behavior Game, which uses behavior management strategies to reduce impulsive, disruptive classroom behavior in a peer group context (Barrishet al.1969) and Mastery Learning, a more precise, enhanced reading curric- ulum (Block & Burns,1976). The 1815 participants that comprised the analytic sample completed at least one of four young adult assessments at approximately 19, 21, 22, and 29 years of age, and must have com- pleted the list of childhood traumatic events used in the 1996 Detroit Area Survey (Breslauet al.1998a), either at the 21- or 29-year assessment. Over half of 3306E. D. Ballard et al.https:/www.cambridge.org/core/terms . https://doi.org/10.1017/S0033291715001300Downloaded from https:/www.cambridge.org/core . George Fox University , on 20 Mar 2017 at 16:34:28 , subject to the Cambridge Core terms of use, available at the sample was female (n= 957; 52.7%), whereas 72% had a minority ethnicity (70.8% African American, 1.2% non-African American minority) and 55.2% received free or reduced meals inﬁrst grade.

Participants included in the analytic sample did not differ from those not included in the initial sample by intervention status or age at entry into the study inﬁrst grade. However, the analytic sample was signiﬁcantly more likely to receive subsidized lunch inﬁrst grade, to be African American and female (Storret al.2014).

This study was reviewed and approved by the Johns Hopkins School of Public Health Institutional Review Board. Written consent was obtained from parents for childhood participation for assessments beyond standard school assessments. Consent was obtained from each young adult at the time of each young adult interview. Participants completed surveys through interviews with research staff who were blind to previous assessments and received rigorous training prior toﬁeld work. Additional study details can be found in previous papers (see Storret al.2004; Wilcox & Anthony,2004; Kellamet al.2008; Wilcox et al.2008).

Measures Child and young adult trauma exposure Participants completed the 1996 Detroit Area Survey on traumatic events to assess trauma exposure in child- hood and young adulthood (Breslauet al.1998b).

Participants were asked if they had ever experienced any of 18 different traumatic events based on criteria A of the DSM-IV (APA,2000). Items in this analysis are included in the Supplementary material.

Upon endorsing a traumatic event, participants responded to follow-up questions regarding their age at each event, which time was the worst experience, and age of worst experience. We deﬁned any traumatic events occurring prior to age 13 as childhood traumas, whereas traumas occurring after age 18 represented young adult traumas, regardless of whether they were considered to be the‘worst experience’. Trauma exposure between ages 13 and 17 were not included in these analyses. Afﬁrmative responses on these items in childhood and young adulthood during any assessment were combined to form the childhood and young adulthood trauma variables. Items with low base rates and similar content were combined to reduce model complexity (see caption ofFig. 1) into nine possible trauma exposure categories.

Parent psychopathology and substance use During the young adult assessments, participants were asked to recall characteristics of their primarycaregivers during their childhood, including parental substance use and psychiatric disorders. These items were modeled after similar items to assess family his- tory in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC; Grant et al.2003). A‘yes’on any of four questions relating to parents (mother or father) having difﬁculties with drugs or alcohol was combined to form a dichotomous measure of parent substance use problems during childhood. Responses to three‘yes/no ’questions about parents (mother or father) experiencing depres- sion, mania, delusions or hallucinations, were com- bined to represent the presence of parental psycho- pathology during a participant’s childhood.

Psychiatric and substance use disorder outcomes Participants were assessed for PTSD, major depressive disorder (MDD), antisocial personality disorder (ASPD), and alcohol and drug use disorders according to diagnostic criteria stipulated in the DSM-IV, text re- vision (APA,2000). All waves used a Composite International Diagnostic Interview (CIDI)-based instru- ment which was fully structured to allow administra- tion by lay interviewers and scoring of diagnoses by computer. The CIDI-UM (Kessleret al.1994) was used in the age 19 assessment and subsequent waves used the World Mental Health Composite International Diagnostic Interview, Version 2.1 (WHO WMH-CIDI) (Kessleret al.1994;WHO,1997), following procedures from the National Comorbidity Survey (Anthony, 1994). The CIDI has demonstrated acceptable validity when compared to independent clinical interview (Wittchen,1994; Andrews & Peters,1998), as well as the PTSD module (Breslauet al.1998b). Only those who met criteria for the diagnosis with onset at age 513 years during any of these assessments were indi- cated as having these diagnoses. Those who reported meeting criteria for the psychiatric diagnoses before the age 13 years were coded as missing data for these variables and were thus not included in evaluation of the outcomes. This procedure was used to maintain evaluation of the time ordered relationship between trauma exposure and psychopathology.

Suicide ideation and attempt Questions regarding suicide attempt or ideation were asked as part of the MDD module in all of the assess- ment waves (additional detail in Supplementary ma- terial). In order to constrain temporality, only those who endorsed attempt or ideation at age513 years were coded as having had suicidal behavior. To ac- count for suicidal behavior being a diagnostic criteria for MDD, a diagnosis of MDD at age513 years was LCA of childhood trauma3307https:/www.cambridge.org/core/terms . https://doi.org/10.1017/S0033291715001300Downloaded from https:/www.cambridge.org/core . George Fox University , on 20 Mar 2017 at 16:34:28 , subject to the Cambridge Core terms of use, available at operationalized without including the criteria regard- ing suicidal behavior.

Criminal convictions Adult criminal records for participants were procured in 2004 from the adult prison database of Maryland Department of Corrections, when participants were 24–25 years old. Thus, these data reﬂect criminal con- victions that occurred between the ages of 18–25 years for participants (additional detail in the Supplementary material). These data were stratiﬁed to represent violent, non-violent, and substance-related criminal convictions.

Health outcomes The National Health and Nutrition Examination Survey III: Data Collection Forms (NHANES; National Center for Health Statistics,1994) interviews have been developed for use in the ongoing National Center for Health Statistics studies. At the 29-year as- sessment, participants responded to items derived from the NHANES interview, which included‘yes’/ ‘no’screening items related to sexually transmittedinfections (STIs), diabetes, stomach ache, headache, and hypertension. During this assessment, height and weight were measured by trained staff with a scale and tape measure, from which body mass index (BMI) was estimated (i.e. weight (lb)/[(height (in) 2) × 703]).

BMI was categorized above and below 30, the cut point for obesity (WHO,1995).

Analysis A LCA was conducted using Mplus version 7.11 (Muthén & Muthén,2013) to model childhood trauma experiences prior to age 13. An LCA is a person- oriented approach to identify distinct subgroups of individuals across a series of indicator variables.

Analyses assumed that distinct groups exist based on the patterns of trauma exposures. Modelﬁt and class viability were identiﬁed using comparison of goodness-of-ﬁt indices and the distinctiveness of classes. Goodness-of-ﬁt indices included the Bayesian Information Criterion (BIC), Vuong–Lo-Mendell– Rubin likelihood ratio test (VLMR-LRT; Loet al.

2001) and bootstrap likelihood ratio test (BLRT; McLachlan & Peel,2000). The auxiliary facility in Fig. 1.Item response probabilities for latent classes of trauma before the age of 13 years. Indicators for the classes were comprised of bundles of items given low response rates on multiple single items. Indicators included the following items:

Assault–includes being captured/kidnapped, shot, stabbed, mugged or beaten up; Rape–includes rape or sexual assault; Witness–includes witnessing a death or discovering a dead body; Injury/Illness–includes motor vehicle accident, life- threatening illness, or other injury to self; Natural Disaster–includes experiencing a natural disaster; Sudden Death–includes experiencing the sudden death of a friend or family member; Close Other Assaulted–includes the physical attack of a family member or friend; Close Other Raped–includes rape or sexual assault of a family member or friend; Close Other Injured– includes motor vehicle accident, life-threatening illness or injury of a friend or family member.

3308E. D. Ballard et al.https:/www.cambridge.org/core/terms . https://doi.org/10.1017/S0033291715001300Downloaded from https:/www.cambridge.org/core . George Fox University , on 20 Mar 2017 at 16:34:28 , subject to the Cambridge Core terms of use, available at Mplus was used to evaluate class differences according to overall and pairwise differences in the outcome across classes with posterior probabilities from mul- tiple imputations (Muthén & Muthén,2013). The young adult outcomes included suicidal behavior, psy- chiatric diagnoses, and health outcomes occurring at age513 years, as well as criminal convictions and traumatic events during young adulthood. Due to the relationship between trauma and PTSD, PTSD symp- tom clusters were also included as potential outcomes.

For more information on LCA, please refer to Collins & Lanza (2009).

Covariates Variables serving as covariates related to contextual, en- vironmental characteristics and demographics and were included in the LCA models to identify the inﬂuence of concurrent childhood adversity experiences on trauma exposure. Contextual characteristics included interven- tion status (0 = control condition, 1 = Good Behavior Game or Mastery Learning), parental psychopathology, and parental substance use. Demographic controls included gender (0 = male, 1 = female), race/ethnicity (0 = European-American, 1 = African-American), and sub- sidized lunch status (0 = no, 1 = yes). Free and reduced meals status served as a proxy variable for low income.

Treatment of missing data Missing data was managed with full information max- imum likelihood (FIML) estimation. FIML produces parameter estimates that are less biased than other missing data strategies even when the data are not missing at random (Graham,2009).

Results Class enumeration An LCA was estimated to identify typical patterns of trauma exposure during childhood in order to createlatent classes. Results from comparing models indi- cated that three classes provided the bestﬁt for the data (seeTable 1). Although the BIC increased as add- itional classes were extracted, otherﬁt indices sup- ported the three class model. Three classes were the highest number of classes for which the LRT and BLRT remained signiﬁcant. Moreover, the entropy was highest for the three class model. The posterior probabilities of class membership demonstrated ad- equate class separation (range 0.029–0.180) and homo- geneity of class (range 0.770–0.994).

The three classes corresponded to distinct and inter- pretable classes of trauma exposure before the age of 13 (seeFig. 1). Theﬁrst class, the Low Childhood Trauma class (n= 1549, 85.2%), had low probabilities of trauma exposure. The second, Violence Exposure class (n= 149, 8.2%), displayed high rates of experien- cing physical assault and physical injury, or witnessing physical assault, physical injury or death. The third, Sexual Assault class (n= 120, 6.6%), demonstrated the highest rates of rape and sexual assault, as well as hav- ing close friends or family also experiencing sexual assault.

Effect of control variables A strong gender effect emerged, where men were sign- iﬁcantly more likely to belong to the Violence Exposure class, and women were more likely to be members of the Sexual Assault class (seeTable 2).

Only young adults belonging to the Sexual Assault classes were signiﬁcantly more likely to have had a caregiver with psychopathology during childhood (p< 0.01) than the Low Childhood Trauma class. No other control variables were signiﬁcantly different among classes.

Effect of trauma class membership on young adult outcomes The childhood trauma classes displayed many differ- ences across young adult outcomes (seeTable 3). The Table 1.Class enumeration for latent class analyses LRT BLRT Smallest class n(%) No. of classes df LL BICΔ2xLLpΔ2xLLpEntropy 225 3091.87 6371.38 212.21 0.007 213.98 <0.001 0.57 240 341 3034.62 6376.97 113.55 0.005 114.50 <0.001 0.72 120 457 3015.77 6459.36 37.39 0.86 37.40 0.33 0.55 113 BIC, Bayesian Information Criterion; BLRT, bootstrapped likelihood-ratio test; df, degrees of freedom; LL, log likelihood; LRT, Lo-Mendell–Rubin likelihood ratio test. LCA of childhood trauma3309https:/www.cambridge.org/core/terms . https://doi.org/10.1017/S0033291715001300Downloaded from https:/www.cambridge.org/core . George Fox University , on 20 Mar 2017 at 16:34:28 , subject to the Cambridge Core terms of use, available at Sexual Assault class, but not the Violence Exposure class, had signiﬁcantly higher rates of both suicide at- tempt, having an attempt plan, and ideation than the Low Childhood Trauma class. Those in both the Violence Exposure and Sexual Assault classes were signiﬁcantly more likely to have a PTSD diagnosis than the Low Childhood Trauma class. By diagnostic symptom clusters of PTSD, only the Sexual Assault class demonstrated signiﬁcantly higher likelihood of re-experiencing and avoidance symptoms than the Low Childhood Trauma class. The Sexual Assault class also had higher rates of MDD than the other two classes, whereas the Violence Exposure class had higher rates of ASPD as well as alcohol and drug use disorders than the other two classes. The Violence Exposure class was signiﬁcantly more likely than the other two classes to have convictions for violent, non- violent and substance-related crimes. The Sexual Assault class was signiﬁcantly less likely to experience substance-related crimes compared to both classes.

Childhood trauma classes were strong predictors of young adult trauma experiences. The Sexual Assault class had signiﬁcantly higher odds of experiencing sex- ual assault during young adulthood than the other classes. Similarly, the Violence Exposure class had signiﬁcantly higher odds of being physically assaulted during young adulthood than the other two classes.The Violence Exposure class also had a higher likeli- hood of witnessing death than the Low Childhood Trauma class. Finally, only one of the physical health outcomes was signiﬁcantly different among the classes. The Sexual Assault class was signiﬁcantly more likely to disclose having had a STI than the other two classes.

Gender effect of outcomes Given the strong effect of gender on child trauma class membership, we conducted follow-up analyses on gender differences in young adult outcomes. We conducted gender-speciﬁcχ 2 tests comparing the Violence Exposure class to the Low Childhood Trauma class among men and among women com- pared the Sexual Assault class to the Low Childhood Trauma class. We found marked differences in out- comes (seeTable 4). The women in the sexual trauma class were signiﬁcantly more likely to have experienced suicide attempt and ideation, all psychiatric diagnoses, stomach problems, and to have had a STI than women in the Low Childhood Trauma class. Men in the Violence Exposure class were more likely to ex- perience ASPD and PTSD and to have had a non-violent criminal conviction, but did not show sign- iﬁcant differences in other psychiatric outcomes Table 2.Covariates of latent class membership Violence Exposure (n= 149)Sexual Assault (n= 120)Low Childhood Trauma (n= 1549)Violence Exposurev.

Low Childhood TraumaSexual Assault v. Low Childhood TraumaSexual Assault v. Violence Exposure bp bp bp Demographics Male gender 134 (90%) 16 (13%) 709 (46%)1.95 0.021* 1.43 <0.001* 3.38 <0.001* African American 110 (74%) 80 (67%) 1096 (71%) 0.25 0.46 0.19 0.56 0.44 0.37 Received subsidized lunch81 (54%) 66 (55%) 857 (55%) 0.29 0.27 0.08 0.77 0.37 0.33 Contextual characteristics GBG/ML intervention56 (38%) 50 (42%) 666 (43%) 0.16 0.52 0.07 0.77 0.01 0.78 Parental psychopathology40 (27%) 50 (42%) 329 (21%) 0.46 0.160.66 0.008*0.10 0.64 Parental problems with drugs or alcohol47 (32%) 52 (43%) 415 (27%) 0.28 0.35 0.30 0.22 0.03 0.95 GBG/ML, Good Behavior Game/Mastery Learning intervention; statistically signiﬁcant parameter estimates are given in bold.

*p< 0.05; statistically signiﬁcant parameter estimates are notated in bold text.

3310E. D. Ballard et al.https:/www.cambridge.org/core/terms . https://doi.org/10.1017/S0033291715001300Downloaded from https:/www.cambridge.org/core . George Fox University , on 20 Mar 2017 at 16:34:28 , subject to the Cambridge Core terms of use, available at including suicidal behavior, health outcomes, or other criminal convictions from men in the Low Childhood Trauma class. Men in the Violence Exposure class were more likely than men in the Low Childhood Trauma class to have witnessed another person’sdeathand womenintheSexualAssaultclassweremorelikely than women in the Low Childhood Trauma class to ex- perience all young adult traumatic events.

There were too few women in the Violence Exposure class and men in the Sexual Assault class to reportany additional analyses beyond descriptive results (Additional detail in the Supplementary material).

Discussion Three latent classes of childhood traumatic experiences before the age of 13 years emerged from an analysis of a community-based sample from an urban environ- ment. Theﬁrst group, which accounted for the major- ity (84%) of the sample reported low levels of all Table 3.Outcomes of latent class membership of child trauma experiences Violence ExposureSexual AssaultLow Childhood TraumaViolence Exposurev.

Low Childhood TraumaSexual Assault v. Low Childhood TraumaViolence Exposurev.

Sexual Assault χ 2 pχ 2 pχ 2 p Suicide outcomes Attempts 12 (8%) 32 (27%) 119 (8%) 0.34 0.55914.03 <0.001* 7.18 0.007* Plan 9 (7%) 20 (17%) 88 (6%) 0.275 0.33513.06 <0.001* 7.25 0.006* Ideation 26 (17%) 41 (34%) 245 (16%) 1.07 0.30213.05 <0.001* 3.84 0.05* Psychiatric diagnostic outcomes ASPD 79 (53%) 49 (41%) 497 (32%)13.80 <0.001*1.09 0.304.60 0.032* MDD 13 (9%) 26 (22%) 195 (13%) 0.36 0.555.35 0.02* 5.68 0.017* PTSD 31 (21%) 38 (32%) 117 (8%)10.35 0.001* 22.53 <0.001* 2.03 0.155 Re-experiencing 44 (30%) 43 (36%) 355 (23%) 2.33 0.1274.61 0.032* 0.14 0.709 Avoidance 9 (6%) 21 (18%) 79 (5%) 0.17 0.6826.92 0.009* 3.37 0.067 Hyper-arousal 16 (11%) 23 (19%) 158 (10%) 0.12 0.731 2.79 0.095 1.02 0.313 Alcohol use disorder 59 (40%) 36 (30%) 433 (28%)8.29 0.004*0.04 0.854.10 0.04* Drug use disorder 52 (35%) 32 (27%) 323 (21%)9.04 0.003*0.34 0.564.24 0.04* Physical health outcomes BMI mean = 28.08 mean = 30.55mean = 30.14 3.46 0.063 0.26 0.612 3.08 0.079 S.D. = 5.75 S.D. = 8.04 S.D. = 7.35 Obesity (BMI530) 33 (22%) 48 (35%) 454 (30%) 0.81 0.37 1.25 0.263 2.35 0.125 Diabetes 1 (1%) 7 (5%) 45 (3%) 1.27 0.261 0.55 0.458 1.77 0.184 Stomach problems 9 (6%) 18 (13%) 93 (6%) 0.07 0.80 3.50 0.061 1.63 0.202 Severe headaches 32 (22%) 46 (33%) 334 (22%) 0.01 0.914 2.90 0.089 1.41 0.235 Hypertension 12 (8%) 22 (16%) 159 (10%) 0.01 0.945 1.34 0.248 0.90 0.344 STI 35 (25%) 59 (44%) 363 (25%) 0.07 0.79610.00 0.002* 6.86 0.009* Criminal convictions Violent crimes 65 (44%) 26 (22%) 388 (25%) 0.54 0.462 0.35 0.557 0.97 0.326 Non-violent crimes 7 (5%) 11 (10%) 108 (7%) 0.38 0.537 3.64 0.056 2.74 0.098 Substance-related crimes67 (45%) 13 (11%) 354 (23%) 1.20 0.274 8.40 0.004*9.97 0.002* Young adulthood trauma (518 yr) Sexual assault 3 (2%) 12 (10%) 33 (2%) 0.152 0.6966.55 0.010* 5.82 0.016* Physical assault 52 (35%) 28 (23%) 355 (23%)5.74 0.017* 0.23 0.6294.85 0.028* Witnessing death 54 (36%) 32 (27%) 295 (19%)9.94 0.002* 0.99 0.319 2.90 0.09 ASPD, Antisocial personality disorder; MDD, major depressive disorder; PTSD, post-traumatic stress disorder; BMI, body mass index; STI, sexually transmitted infection.

Suicidal behavior and psychiatric diagnoses reﬂect onset from the age of513 years; criminal convictions and young adult trauma reﬂect experiences from the age of518 years.

*p< 0.05; statistically signiﬁcant parameter estimates are given in bold. LCA of childhood trauma3311https:/www.cambridge.org/core/terms . https://doi.org/10.1017/S0033291715001300Downloaded from https:/www.cambridge.org/core . George Fox University , on 20 Mar 2017 at 16:34:28 , subject to the Cambridge Core terms of use, available at traumatic experiences. The second class comprised 8% of the sample, was predominately male, reported the highest levels of witnessing violence, physical assault, physical injury and the sudden death of a close friend or family member. The third group comprised 8% of the sample, which was predominately female, reported the highest levels of sexual assault for themselves and knowing someone who had been sexually assaulted.

The second and third classes had different proﬁles of psychiatric diagnoses occurring at age513 years as well as the same types of trauma exposures in young adulthood. Distinct patterns of outcomes emergedwhen analyses were stratiﬁed by gender; women in the Sexual Assault group reported a wide range of negative psychiatric outcomes, while men in the vio- lence exposure class reported a pattern of outcomes limited to post-traumatic stress and antisocial personality.

The creation of these latent classes suggests cluster- ing of types of traumatic experiences (physicalv.sex- ual assault) by gender. Differences in exposure to traumatic experiences by gender has been reﬂected in the Youth Risk Behavior Survey (YRBS), in which 10% of female and 4% of male high-school students Table 4.Gender effects of outcomes of latent classes of child trauma experiences Males only Females only Violence Exposure (n= 134)Low Childhood Trauma (n= 709)pSexual Assault (n= 104)Low Childhood Trauma (n= 840)p Suicide outcomes Attempts 10 (7%) 40 (6%) 0.25828(27%) 74(9%) <0.001* Plan 8 (7%) 37 (6%) 0.43917 (16%) 51 (6%) <0.001* Ideation 22 (16%) 109 (15%) 0.41436 (35%) 136 (16%) <0.001* Psychiatric diagnoses ASPD76 (56%) 312 (44%) 0.005*39 (36%) 185 (22%) 0.001* MDD 12 (9%) 58 (8%) 0.41627 (22%) 132 (16%) 0.033* PTSD26 (19%) 57 (8%) <0.001*33 (31%) 60 (7%) <0.001* Re-experiencing40 (30%) 134 (27%) 0.010*39 (43%) 221 (32%) 0.019* Avoidance 9 (7%) 31 (6%) 0.22720 (22%) 48 (7%) <0.001* Hyper-arousal 16 (12%) 56 (11%) 0.14222 (25%) 102 (15%) 0.015* Alcohol use disorder 57 (47%) 269 (41%) 0.14229 (28%) 164 (21%) 0.035* Drug use disorder 49 (41%) 218 (32%) 0.07525 (21%) 105 (13%) 0.002* Health outcomes BMI mean = 27.93 mean = 29.19 0.051 mean = 30.36 mean = 30.80 0.638 S.D. = 5.37 S.D. = 6.15 S.D. = 7.97 S.D. = 8.01 Obesity (BMI530) 23 (31%) 122 (35%) 0.347 34 (49%) 235 (46%) 0.331 Diabetes 1(1%) 9 (2%) 0.465 5 (6%) 37 (5%) 0.537 Stomach problems 8 (6%) 35 (7%) 0.47215 (16%) 60 (8%) 0.017* Severe headaches 28 (20%) 101 (20%) 0.083 34 (38%) 239 (33%) 0.294 Hypertension 11 (9%) 68 (14%) 0.269 17 (19%) 93 (14%) 0.106 STI 31 (23%) 137 (19%) 0.20446 (43%) 233 (27%) 0.001* Criminal convictions Violent crimes 61 (46%) 286 (40%) 0.556 19 (63%) 102 (62%) 0.539 Non-violent crimes7 (46%) 63 (42%) 0.045* 8 (26%) 45 (27%) 0.563 Substance-related crimes 62 (46%) 288 (41%) 0.501 8 (26%) 66 (40%) 0.113 Traumatic events in young adulthood Sexual assault 1(1%) 1(1%) 0.29311 (9%) 32 (4%) 0.005* Physical assault 51 (38%) 246 (34%) 0.25724 (22%) 109 (13%) 0.006* Witnessing death52 (39%) 180 (25%) 0.001*25 (23%) 115 (14%) 0.008* ASPD, Antisocial personality disorder; MDD, major depressive disorder; PTSD, post-traumatic stress disorder; BMI, body mass index; STI, sexually transmitted infection.

Suicidal behavior and psychiatric diagnoses reﬂect onset from the age of513 years; criminal convictions and young adult trauma reﬂect experiences from the age of518 years.

*p< 0.05; statistically signiﬁcant parameter estimates are given in bold. 3312E. D. Ballard et al.https:/www.cambridge.org/core/terms . https://doi.org/10.1017/S0033291715001300Downloaded from https:/www.cambridge.org/core . George Fox University , on 20 Mar 2017 at 16:34:28 , subject to the Cambridge Core terms of use, available at report that they have been forced to have sexual inter- course (CDC,2015), as well as the ACE study in which 25% of the women and 16% of the men reported sexual abuse in childhood (CDC,2014). Similarly, an analysis of the Detroit Area Survey of Trauma found that life- time exposure to assaultive trauma and witnessing a death were more likely in men than women (43%v.

32% for assaultive violence; 40%v. 19% for witnessing death or violence) (Breslauet al.1998a). This analysis further extends this literature to suggest that these gen- der differences in trauma exposure begin before the age of 13 years and reinforces the importance of gender as a critical construct in trauma research.

The relationship of parental psychopathology to the Sexual Assault class highlights the signiﬁcance of fa- milial environment and possible genetic effects on the association between childhood trauma and psychi- atric diagnosis. On one hand, there is a robust litera- ture linking parental psychopathology with abuse exposure in offspring (Chafﬁnet al.1996; Walshet al.

2002) with some analyses proposing that childhood abuse may, in part, mediate the intergenerational transmission between parent and child diagnoses (Verona & Sachs-Ericsson,2005). On the other hand, recent evaluations have found interactions between genetic polymorphisms and trauma exposure to pre- dict the development of PTSD (Liberzonet al.2014), which may similarly underlie the relationship between family psychopathology, trauma and offspring diag- noses. Analyses of adoptees have suggested a com- bination of both biological parental history with adoptive parental experiences lead to increased risk of outcomes such as offspring hospitalization due to suicide attempt (Wilcoxet al.2012), highlighting the importance of potential interactions between genetics and familial environment. Further analyses can investi- gate potential genetic effects, whether through single polymorphisms or more general polygenetic risk scores, to evaluate the relationship between childhood traumatic experiences and later psychiatric diagnoses.

Similarly, important familial factors which may have an impact on exposure to traumatic experience and may be related to parental psychopathology, such as parental physical or psychiatric impairment, stress, neglect or decreased monitoring of child behavior, can also be investigated using these latent classes.

Psychiatric outcomes associated with class member- ship underscore that speciﬁc early traumatic experi- ences are associated with distinct consequences, including, but not limited to PTSD. The women in the Sexual Assault class were more likely to experience global impairment in terms of increased suicidal thoughts and behaviors as well as increased incidence of almost all of the examined psychiatric diagnoses, when compared to the women in the low traumaclass. Men in the Violence Exposure class had more cir- cumscribed effects, with increased rates of ASPD and PTSD compared to men in the low trauma class.

Results suggest that patterns of childhood traumatic experiences may be associated with speciﬁc transdiag- nostic vulnerabilities (Teicher & Samson,2013), which may be related to potential epigenetic changes as well as neurobiological pathways such as reduced hippo- campal volume or amygdala reactivity. Further inves- tigation of potential epigenetic or neurobiological differences between the three classes may highlight distinct neurodevelopmental pathways to psychiatric outcomes.

Out of the other negative outcomes included in this model, only STIs and traumatic events in young adult- hood were consistently associated with class member- ship. STIs were closely associated with the Sexual Assault class; it is not known whether these infections were transmitted as a result of the assaults in child- hood or in young adulthood or related to other sexual behavior. With the exception of stomach problems, which have been associated with stress and anxiety (Means-Christensenet al.2008), none of the other life- time health outcomes were associated with class mem- bership. Only non-violent criminal convictions were associated with Violence Exposure class when analyses were strati ﬁed by gender, suggesting that the associ- ation between childhood trauma and outcomes such as alcohol and drug use disorders or ASPD did not ex- tend to legal repercussions. Class membership was associated with traumatic experiences in young adult- hood, particularly for the Sexual Assault class, in which young adult women were more likely to experi- ence sexual assault, physical assault and witness death.

These results replicate previous work in this area (Aciernoet al.1999) and highlight the importance of early intervention for survivors of child trauma. As data collection ended at age 29 years, it is not known how these traumatic experiences in young adulthood then impacted further experiences in middle adult- hood and beyond.

Several characteristics of the study limit theﬁndings.

First, traumatic experiences reported in young adult- hood may have been subject to reporting biases, par- ticularly by gender. Although we may not have captured all possible trauma events given this meth- odological approach, research suggests that the false positive disclosures of trauma are unlikely (Hardt & Rutter,2004). Additionally, the perpetrator of the trauma was not recorded; therefore, it is not known whether the traumatic exposure was instigated by someone in the family or in the larger community.

Second, the order of onset among multiple psychiatric outcomes was not evaluated. For example, it is pos- sible that individuals developed PTSD, which putLCA of childhood trauma3313https:/www.cambridge.org/core/terms . https://doi.org/10.1017/S0033291715001300Downloaded from https:/www.cambridge.org/core . George Fox University , on 20 Mar 2017 at 16:34:28 , subject to the Cambridge Core terms of use, available at them at risk for other psychiatric outcomes, such as suicide attempts (Wilcoxet al.2009). Third, physical health outcomes and parental psychopathology and substance abuse were not conﬁrmed by clinician or medical record diagnosis. Reported family history of psychiatric diagnoses is limited, but may be more reli- able for diagnoses such as depression, schizophrenia or substance abuse (Hardt & Franke,2007). Fourth, the sample size did not permit further regression models of the impact on gender on psychopathology; there were too few women in the Violence Exposure class and too few men in the Sexual Assault class to investi- gate possible interactions. Further investigations of the role of gender on both reporting trauma as well as the development of negative psychiatric outcomes after traumatic experiences, is indicated. Fifth, endorsement of many traumatic experiences was quite low, which may have taxed the computation involved in estimat- ing the LCA. Finally, it is possible that the combination of trauma exposure in childhood and young adulthood may have led to adverse psychiatric outcomes by age 30. It is also possible that a traumatic experience occur- ring after childhood could have been considered a ‘worse’experience and more directly led to the psychi- atric outcomes. Further analysis using these classes of childhood trauma exposure with the addition of ado- lescent and young adult trauma exposure is indicated to determine the effect of cumulative trauma.

Conclusions Latent classes of childhood traumatic experiences be- fore the age of 13 years were computed and studied using an urban community sample followed from childhood to age 29 years. Assaultive traumatic experi- ences in childhood, both sexual and non-sexual, were found to predict negative psychiatric outcomes by young adulthood, including re- traumatization.

Childhood sexual abuse in our sample predicted more global impairment in women, whereas violence exposure in men predicted more limited outcomes. In our sample, we identiﬁed unique developmental path- ways by type of childhood trauma exposure to young adult negative psychiatric and behavioral outcomes.

Supplementary material For supplementary material accompanying this paper visit http://dx.doi.org/10.1017/S0033291715001300.

Acknowledgements This work was supported by several National Institute of Health grants over the span of the prospective study:

National Institute of Mental Health (MH090480,MH71395, MH 71395, MH 48802) and National Institute on Drug Abuse (DA09897, DA04392, and DA019805).

Declaration of Interest None.

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