The Impact of Physical and Sexual Violence on Opioid Consequences among Trauma- exposed Individuals Recruited from the Community who Use Opioids

Abstract Interpersonal violence and opioid use disorder are significant and intersecting public health concerns in the United States. The current study evaluated the consequences associated with opioid use as a function of history of interpersonal trauma, specifically physical and sexual violence. Participants were 84 trauma-exposed individuals recruited from the community who use opioids ( M age = 43.5 50% men; 55% white). Whereas no significant differences emerged in the consequences of opioid use based on a history of physical violence, individuals with a history of sexual violence demonstrated higher levels of impulsive consequences of opioid use compared to individuals without a history of sexual violence. These data highlight the importance of considering the role of sexual violence in the context of opioid use disorder treatment.


Introduction
Opioid use disorder is a growing public health concern in the United States with high prevalence, morbidity, and mortality (1)(2)(3). The Centers for Disease Control (CDC) estimated there have been more than 500,000 opioid overdose deaths in the United States over the past two decades (4). Nationally, fatal opioid overdoses reached an all-time high in the United States in 2022, with more than 80,000 opioidrelated overdose death reported (5). Whereas opioid use is emerging as an epidemic, the United States has faced a chronic struggle with interpersonal trauma, which include sexual and physical violence. Sexual violence encompasses forcing or attempting to force a person to engage in sexual activity or touching and physical violence involves hurting, attempting to hurt, or threatening to hurt another person by use of physical force or weapons (6). In the United States, both physical and sexual violence is highly prevalent. For example, in their lifetimes, 23.1% of women and 19.3% of men experienced physical violence (7), 19.3% of women and 1.7% of men have been raped, and 43.9% of women and 23.4% of men experienced other forms of sexual violence such as unwanted sexual contact (6).
These two public health concerns, namely opioid use and interpersonal trauma, are interrelated and bidirectional in nature. Prior research has highlighted the role of interpersonal trauma in contributing to problematic opioid use outcomes, including opioid use disorder and opioid overdose (8-10). This can be explained by the self-medication model which posits that individuals with a history of interpersonal trauma may use opioids to cope with trauma-related psychological distress [e.g., posttraumatic stress disorder (PTSD)], physical pain and injuries, and psychosomatic symptoms (e.g., headaches, backpains), which increases their risk for developing opioid use disorder (11)(12)(13)(14)(15). Opioid use also increases the risk of experiencing interpersonal trauma (16-21). Contextual factors such as the decreased ability to assess risk when impaired by drugs, dependence on sexual partners for drug supply, coercion from an abusive partner to use drugs, and being forced to have sex in exchange for drugs or money, have all shown an increased risk for interpersonal trauma (18,(22)(23)(24)(25). Notably, the co-occurrence of opioid use and interpersonal trauma is marked by worsened clinical consequences associated with opioid use (e.g., exacerbations of psychological distress, increased opioid use), increased social consequences (e.g., legal, nancial, and/or family problems), and poorer opioid use disorder treatment outcomes (e.g., higher rates of treatment drop out, more missed treatment appointments) (26-33).
Whereas extant research provides robust evidence for the relationship between opioid use and interpersonal trauma, there is an important gap. Namely, prior studies tended to limit their investigation to a single type of interpersonal trauma [e.g., only sexual violence (11,18,33,34)]. When studies have examined multiple types of interpersonal trauma, they combined different types of interpersonal violence (such as sexual violence and physical violence) in a single composite variable (35)(36)(37). This limits insight into whether different types of interpersonal trauma are differently related to consequences associated with opioid use. Nascent research has begun investigating the role of different types of trauma in the development and maintenance of opioid use disorder. For example, one study examined the impact of different types of interpersonal violence (i.e., intimate partner violence, sexual assault, and adverse childhood experiences) on problematic opioid use and found that only intimate partner violence and adverse childhood experiences were related to problematic opioid use (38). Two studies examined the pathways from childhood abuse to lifetime problematic opioid use among women and found that only sexual abuse-but not physical abuse, emotional abuse, or neglect-was associated with problematic opioid use (39,40). These ndings underscore the need for further investigation into the potentially differential impact of distinct types of interpersonal trauma.

Present Study
Opioid use and interpersonal trauma co-occur at high rates (9,11) and leads to worse outcomes (26, 27,30,33). Prior investigation into the impact of interpersonal trauma among individuals who use opioids is limited by examination of single types of trauma (11,33) or by combining different types of trauma into a single composite variable (38), which limits our understanding of the potentially unique impact of different types of trauma. Robust evidence indicates that a history of sexual violence, compared to other interpersonal trauma types, leads to worse outcomes (41,42). For example, seminal studies have found that survivors of sexual violence endorse higher levels of PTSD symptoms compared to survivors of combat trauma (43)(44)(45), motor vehicle accident (46), and even physical violence (41,42). Thus, one may expect that sexual violence, in particular, would be associated with severe consequences of opioid use as well. Thus, the current study investigated consequences associated with opioid use based on participant's history of interpersonal trauma, speci cally physical and sexual violence. It was hypothesized as follows: Hypothesis 1. Individuals with a history of physical violence would report signi cantly more consequences of opioid use, compared to those without a history of physical violence. Hypothesis 2. Individuals with a history of sexual violence would report signi cantly more consequences of opioid use, compared to those without a history of sexual violence.

Participants
Participants were recruited from the Providence metropolitan area, an urban region anchored by the city of Providence, Rhode Island with a population of greater than 1.6 million. Recruitment materials were posted in community establishments throughout Providence County, Rhode Island including grocery stores, laundromats, and shops; selected state o ces such as the O ce of Housing and Community Development; and waiting rooms, bathrooms, and exam rooms of urban-area primary care clinics; as well as in website postings (e.g., Craigslist). Further, research assistants recruited at/alongside local harm reduction agencies (e.g., street outreach, warming centers) that serve individuals who use opioids (e.g., needle exchange). Eligibility was determined through self-report during a phone or in-person screen. Participants were individuals who had experienced trauma in their lifetime and used illegal opioids (e.g., heroin) or misused prescription opioids (i.e., used prescription opioids without a prescription or in a manner not prescribed such as taking a higher dose than prescribed or for a longer period than prescribed) during the past 30 days. Additional inclusion criteria were: (1) age 18 or older, (2) uent in the English language, and (3) Table 1.

Procedures
All procedures were reviewed and approved by the [redacted] Institutional Review Board. The larger study entailed (a) a baseline session, (b) 30 days of ecological momentary assessment ( ve surveys per day) on a smartphone app, and (c) a follow-up session. The current study used data from the baseline session. Baseline sessions were conducted by a clinical psychology doctoral student in a private o ce to protect participants' safety and con dentiality. After providing informed consent, participants were interviewed using a structured diagnostic assessment and then answered self-report measures on a computer. Participants were compensated with $25 for completing the baseline session. Participants were provided with a list of community resources. Assistance with referrals was provided upon participant request. The principal investigator (author [redacted]), a licensed psychologist in the state of Rhode Island, was available on-call if participants required additional trauma-and/or substance-related support.

Interpersonal Trauma
The 17-item Life Events Checklist for DSM-5 [LEC-5; (47)] was used to assess a history of physical violence or sexual violence. Participants rated each time with six response options: happened to men, witnessed it, learned about it, part of my job, not sure, or doesn't apply. Speci cally, items "Assault with a weapon (for example, being shot, stabbed, threatened with a knife, gun, bomb)" and "Physical assault (for example, being attacked, hit, slapped, kicked, beaten up)" were used to measure the experience of physical violence, whereas "Sexual assault (rape, attempted rape, made to perform any type of sexual act through force or threat of harm)" and "Other unwanted or uncomfortable sexual experience" were used to measure the experience of sexual violence. For the current study, a positive physical or sexual violence was indicated when participants selected either "happened to me," "witnessed it," "learned about it," or "part of my job," as consistent with Criterion A for posttraumatic stress disorder in the Diagnostic

Data Analysis
Descriptive data for the primary study variables were calculated. In order to examine whether consequences of opioid use varied across history of physical violence, independent sample t-tests were conducted where a history of physical violence (0 = no history of physical violence, 1 = history of physical violence) was entered as the independent variable, and consequences of opioid use (i.e., physical, social, intrapersonal, interpersonal, and impulsive) were entered as dependent variables. Similarly, to examine whether consequences of opioid use varied across a history of sexual violence, independent sample ttests were conducted where a history of sexual violence (0 = no history of sexual violence, 1 = history of sexual violence) was entered as the independent variable and consequences of opioid use (i.e., physical, social, intrapersonal, interpersonal, and impulsive) were entered as dependent variables.

Preliminary Analyses
When examining past-month opioid use in the current sample, 59.5% (n = 50) reported using heroin, 70.2% (n = 59) reported using prescription opioids without a prescription or in a manner not prescribed such as taking a higher dose than prescribed or for a longer period than prescribed, and 82.1% (n = 69) reported using synthetic opioids (e.g., Fentanyl). When examining interpersonal violence in the current sample, over half of the sample reported a history of physical (n = 56; 66.7%) or sexual (n = 47; 56.0%) violence. Over half of the sample, (n = 45, 53.57%) endorsed experiencing both physical and sexual violence. Further details regarding the prevalence of history of physical and sexual violence are summarized in Table 2.

Impact Of Physical And Sexual Violence
See Table 3

Discussion
The current study investigated the unique impact of physical and sexual violence on consequences associated with opioid use among trauma-exposed individuals recruited from the community who use opioids. The link between interpersonal trauma and increased consequences associated with opioid use has been well-established in prior literature (26,27,30,33). To our knowledge, this is the rst study to examine whether the consequences of opioid use differed based on participant's history of interpersonal trauma, speci cally physical and sexual violence.
Contrary to our hypothesis, individuals with a history of physical violence reported similar levels of consequences associated with opioid use, compared to individuals without a history of physical violence. Our second hypothesis, speci cally, individuals with a history of sexual violence would report higher levels of consequences associated with opioid use, compared to individuals without a history of sexual violence, was partially supported. Speci cally, results suggested that individuals with a history of sexual violence demonstrated signi cantly high levels of impulsive consequences-but not physical, social, intrapersonal, or interpersonal consequences-of opioid use compared to individuals without a history of sexual violence. Results are in line with prior studies that indicate sexual violence, compared to other types of violence, is particularly detrimental, even when compared to physical violence (41,42). It warrants mention that the current sample consisted of all trauma-exposed individuals. This history of trauma may explain why most of the consequences of opioid use, except for impulsive consequences, did not differ among individuals who did and did not experience physical or sexual violence. Future research is needed to compare individuals with physical and sexual violence to those without any history of trauma on their consequences of opioid use.
Notably, results highlight the particularly adverse impact of sexual violence on impulsive consequences of opioid use. The link between a history of sexual violence and consequences associated with opioid use, especially impulsive consequences, may be understood through the lens of emotion dysregulation. Emotion dysregulation is a multifaceted construct that refers to di culties understanding and modulating emotions (50). Robust evidence shows that individuals with a history of sexual violence demonstrate higher levels of emotion dysregulation compared to those without a history of sexual violence (51)(52)(53). Emotion dysregulation, in turn, is also associated with impulsive behaviors (54-56), including among survivors of sexual violence (52,57,58). Further, de cits in emotion regulation among survivors of sexual violence has also been linked to greater problematic substance use [for a review see (59)], including opioid use (11,60), which is consistent with the self-medication hypothesis (61). Collectively, ndings suggest the utility of targeting emotion dysregulation to address impulsivity consequences of opioid use among individuals with a history of sexual violence [for a review see (62)].
Study results have several implications for clinical practice and research. Given the detrimental impact of comorbid sexual violence and problematic opioid use, clinicians should incorporate regular screening for sexual violence in treatment for opioid use disorder. Given that many survivors of sexual violence may delay disclosure of violence to treatment providers (63) and problematic opioid use is associated with increased risk for experiencing sexual violence (18), it is important for clinicians to routinely screen for sexual violence. Further efforts need to be targeted towards the development and evaluation of interventions aimed at concomitantly reducing sexual violence and problematic opioid use to effect a change in harmful effects of both sexual violence and opioid use. Such efforts can be built on prior work that has already been done on alcohol and its relationship to sexual violence while heeding to unique differences that may exist between alcohol-involved sexual violence and opioid-involved sexual violence (64). Given the bidirectional nature of sexual violence and problematic opioid use, interventions targeting opioid use among survivors of sexual violence also need to be developed and evaluated (34). Finally, the results highlight the need to incorporate a trauma-informed approach in care and treatment for opioid use disorder such as fostering collaboration, maximizing client's choice and control, emphasizing client's strengths, and creating a safe atmosphere (65).

Limitations And Future Directions
The results of the current study should be interpreted in the context of several limitations, which also pave the way for future directions. First, our relatively small sample size limits investigation into gender differences, polyvictimization (i.e., experiencing more than one type of interpersonal violence), and revictimization (i.e., repeated occurrences of interpersonal violence). Preliminary research suggests gender differences in the relation between interpersonal violence and opioid use (38, 40), and both polyvictimization and revictimization are associated with increased substance use (66, 67). Thus, future studies with larger sample size should determine the role of gender, polyvictimization, and revictimization in the relations between both physical and sexual violence and problematic opioid use. Second, given that cross-sectional ndings preclude temporal interpretations, future longitudinal studies with multiple time points are needed to establish the likely cyclical relation between sexual violence and problematic opioid use. Finally, ndings cannot be assumed to generalize to other populations characterized by opioid use, including individuals seeking outpatient or residential treatment for problematic opioid use. Thus, ndings require replication across other populations that use opioids.

Conclusion
The current study investigated differences in consequences associated with opioid use depending on history of interpersonal trauma, particularly physical and sexual violence, among trauma-exposed individuals recruited from the community who use opioids. Results suggest that individuals with a history of sexual violence in particular demonstrated a higher level of impulsive consequences associated with opioid use. Findings emphasize the need to concomitantly address both sexual violence and problematic opioid use.

Consent for publication: Not applicable
Availability of data and materials: The datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request.
Competing interests: The authors declare that they have no competing interests.
Funding: This research was supported by the Center for Biomedical Research and Excellence (COBRE) on Opioids and Overdose funded by the National Institute on General Medical Sciences (P20 GM125507).
Work on this paper by the third author (SRF) was supported by the National Institute on Drug Abuse Grant F31 DA051167.
Authors' contributions: PHB was involved in the conceptualization of the study, data analysis, and writing.
LMO was involved in study conceptualization and writing. SRF was involved in data analysis and reviewing and editing the manuscript. NGN was involved in data analysis and reviewing and editing the manuscript. NHW was involved in study conceptualization, data analysis, and writing. All authors read and approved the nal manuscript. Prefer not to respond 5 (6.0%)  Note. Bolded consequence is signi cant at p < .05.