Introduction

Child maltreatment (CM) is a complex global problem which encompasses physical and emotional mistreatment, sexual abuse, neglect, and negligent child care, as well as commercial sexual exploitation and trafficking of minors.¹ It is recognized internationally as a severe public health, human rights, legal, and social issue. Violent and traumatic events in childhood have major repercussions on mental and physical health, resulting in immediate and/or long-term harm to the child’s dignity and development.¹,²

CM has been reported by one in every four adults, while one in five women and one in 13 men worldwide report being sexually abused in childhood.² In Brazil, an average of three allegations of child and adolescent sexual exploitation were registered every hour in 2014.³ Almost 21.7% of Brazilians report childhood violence at least once over the course of their lives, according to data from the II National Alcohol and Drugs Survey.⁴

Another survey conducted by Zanoti-Jeronymo et al. in a multistage sample of 3,007 individuals from all Brazilian regions, aged 14 or older, from 2005-2006 found a prevalence of physical abuse in childhood of 44.1% (33.8% moderate, 10.3% severe).⁵ In the same sample, the prevalence of exposure to parental violence was 26.1% (7.5% moderate and 18.6% severe).

Adults with substance use disorders have reported higher rates of child sexual abuse and neglect than their counterparts without such disorders.⁶-⁸ About 40-90% of substance users report a history of childhood abuse; individuals who experience abuse in childhood are twice as likely to have substance use disorders in adulthood when compared to the general population.⁶ Physical, sexual, and emotional abuse or neglect have been identified as predictors of persistent dependence on alcohol (odds ratio [OR] 1.50-2.99, 95% confidence interval [95%CI] 1.04-4.68) and nicotine (OR 1.37-1.74, 95%CI 1.13-2.11).⁹ It has been estimated that 30% of psychiatric disorders diagnosed in adults might be directly linked to childhood experiences.

These findings suggest that child abuse increases the likelihood of substance use and doubles the incidence of psychopathological comorbidity.¹⁰ It also seems to be associated with earlier drug use initiation¹¹-¹³ and may play a significant role in the development and severity of dependence on alcohol, nicotine, and other drugs, through an internalizing pathway involving negative effects.¹⁴-¹⁶

The international literature suggests that CM is associated with a number of mental, social, and physical health problems in adulthood. Psychosis, depression, anxiety, suicidality, posttraumatic stress disorder, and early polydrug abuse are among the psychiatric conditions mentioned,⁶ while antisocial behavior, interpersonal and academic difficulties, aggression, poor coping skills, low self-esteem, emotional instability, criminal behavior, hopelessness, revictimization, high-risk sexual behavior in adulthood,¹⁷ and physical health problems¹⁸,¹⁹ stand out among the problems reported. Individuals who have been sexually abused may exhibit elevated rates of psychiatric and substance use disorders as a consequence of their traumatic experience. Any level of sexual abuse may be associated with polydrug use in later life¹⁰ and high-risk sexual behavior in adulthood.¹⁷,²⁰

These conditions seem to have gender-related variances in diverse dependence development outcomes.²¹-²³ Women are more likely to report sexual, physical, and emotional abuse, at rates varying from 77 to 90%. A study conducted in Mexico with 112 female inmates found that revictimization abuse occurred at a rate of 78.1%.¹⁹

The relationship between CM, high-risk sexual behavior in adulthood, and drug use has not been extensively investigated.¹¹,¹⁹,²⁴ A conceptual model that tries to explain the connection between CM, later risky sexual behavior, and alcohol consumption concurs with Miller, who hypothesized the following mechanisms: a) substance use to cope with early CM trauma (more studies with alcohol than any other drug); b) poor sexual adjustment (unprotected sex, multiple partners, sex trading, and adult sexual revictimization; c) abuse-related mental illness (paraphilic disorders); and d) riskier social networks (increased odds of substance use).²⁵

In this study, we hypothesized that adults who seek treatment for substance abuse would present with high rates of CM prevalence, and that these rates would be significantly higher in women. Furthermore, we hypothesized that substance-dependent patients who seek treatment with a history of CM might report alcohol and cocaine as their drugs of choice (DOC) and adoption of high-risk sexual behaviors in adulthood.

Little is known about the prevalence of CM experienced by adult substance users in low- and middle-income countries (LMIC), especially in Latin American countries, which present the highest estimates of childhood trauma in the world.²⁶,²⁷ Although CM has a high worldwide economic cost and serious lifelong consequences, studies are still scarce.² The present study advances in relation to prior research by examining and discussing a combination of clinical aspects related to early child sexual abuse, maltreatment experiences, and later sexual behavior in adulthood (mainly sexual addiction and paraphilic symptoms) in a clinical sample of Brazilian drug users. To the best of our knowledge, there is no other study on this topic. Our aim was to investigate the prevalence of early CM experiences and its association with later sexual behavior among adult substance-dependent patients undergoing treatment.

Methods

This cross-sectional study was conducted at a public specialized outpatient unit for addiction treatment (Ambulatório Médico de Especialidades de Psiquiatria Dra. Jandira Masur), in São Paulo, Brazil. The sample comprised consecutive admissions of 134 drug users, male and female, aged 18 to 60 years. Data collection was conducted from February 2013 to January 2014. This study was approved by the ethics committee of Universidade Federal de São Paulo (UNIFESP; protocol 56520), and all subjects provided written informed consent. The research protocol was self-administered. No refusals were recorded.

Results

Sociodemographic data are displayed in Table 1. Patients were predominantly male (76.1%) and single (76.1%), with a mean age of 34 years (SD 10.6 years, range 18 to 66 years). The typical subject profile was Caucasian (68.8%), non-Catholic (70.1%), employed (60.6%), and with fewer than 8 years of formal education (79.1%). Most of the sample had experienced situations of physical neglect (n=105; 78.4%), emotional neglect (n=118; 88.1%), emotional abuse (n=108; 80.6%), physical abuse (n=86; 64.2%), and sexual abuse (n=42; 31.3%).

Discussion

The main findings of the present study indicate high rates of physical neglect (78.4%), emotional neglect (88.1%), emotional abuse (80.6%), and sexual abuse (31.3%) among care-seeking substance-dependent adults. CM rates were higher for women than for men. Estimates of CM in the general population indicate that nearly one-quarter of adults (22.6%) worldwide have suffered physical abuse during childhood, 36.3% experienced emotional abuse, and 16.3% experienced physical neglect, with no significant differences between boys and girls.² We also observed an association between CM and likelihood of sex addiction, paraphilic thoughts, and sexual victimization in adulthood, corroborating our initial hypotheses. Only one of the suggested hypotheses was not confirmed, since no association between alcohol or cocaine as the DOC in adulthood and CM was found on bivariate analysis of this sample; however, on multivariate analyses, cocaine was associated with CM.

The findings of this study corroborate the international literature, which points to a higher prevalence of sexual and physical abuse during childhood among substance-dependent adults.⁵,⁶,²³ CM and addiction include a wide range of complex social and economic ramifications.³⁴ There is extensive evidence associating CM with a variety of negative physical and mental health consequences throughout the life cycle.⁶,¹⁸,¹⁹

Two models have been used to explain such negative outcomes. The first one posits that individuals with a history of child abuse (sexual, physical, and emotional) are likely to experience general problems related to emotions and behavior. The second pattern suggests that certain types of abuse in childhood are associated with specific outcomes in adulthood. Among substance users, different types of abuse are uniquely associated with specific negative effects.¹⁷ For example, a North American cross-sectional study conducted by Banducci et al. in a group of 280 drug-dependent patients revealed that a history of child sexual abuse predicted exchange of sex for cocaine and heroin, increased number of arrests for prostitution, unprotected sex practices with a casual partner during the year prior to the interview, and experiencing low sexual arousal when sober. In this same study, physical abuse exclusively predicted the number of arrests for robbery and weapon-related offenses.⁶ Although there is no substantial support for the general model, the differential model provides greater specificity for the hypothetical relationship between certain types of abuse and specific outcomes.⁶

Physical and sexual abuse plus the association with consequences of substance abuse in patients admitted to a detoxification program were assessed in a study conducted by Liebschutz et al. The results revealed high levels of physical or sexual abuse among both men (81%) and women (69%). This study also highlighted the vulnerability of women to sexual and physical abuse at all stages of life after the initial victimization experience.³⁵

An important finding refers to gender issues; it is worth observing that, in our sample, female drug users reported higher percentages of sexual abuse and physical negligence in childhood when compared to men. Numerous forms of violence against women may occur at any stage of the life cycle, since violence is rooted in cultural discrimination and gender submission (i.e., a condition of inferiority compared to men). These findings corroborate data from other studies which reported that drug users, mainly women, report high rates of abuse exposure in childhood.⁸,¹⁹

Another curious finding in this sample was found in relation to religion: non-Catholics reported more emotional abuse when compared to Catholics. This seems to make perfect sense, as Brazil is defined by religious pluralism in regard to the public expression of religion; however, the various denominations of Christianity have imposed their representations. The hegemony of Christianity in Brazil has negatively impacted African-Brazilian religions, with increased religious intolerance in the country as seen in regards to other religions around the world.³⁶,³⁷ The National Secretariat of Human Rights reported 697 cases of religious intolerance in the states of São Paulo, Rio de Janeiro, and Minas Gerais, Brazil, between 2011 and December 2015. In the state of Rio de Janeiro, Centro de Promoção da Liberdade Religiosa e Direitos Humanos (CEPLIR), the agency which protects and promotes religious freedom and human rights, reported 1,014 cases between July 2012 and August 2015, of which 71% were against followers of African-based religions, 7.7% against Evangelical Christians, 3.8% against Catholics, 3.8% against Jews, and 3.8% against religious freedom in general. It is believed that the impact of experiencing religious intolerance in early life may have repercussions in the future, aside from being in a human rights violation.³⁸

In our sample, there was no significant association between sexual abuse and other sociodemographic characteristics, nor DOC. The same was found in a literature review conducted by Verdolini et al., which showed that, even though sexual abuse has been studied extensively, neglect, physical, and emotional abuse appear to be more frequent within the population of patients who have suffered any type of abuse.³⁹

In our sample, alcohol, tobacco, and cocaine were the predominant DOCs. Individuals who had experienced emotional abuse had elevated levels of tobacco use. Cocaine and cannabis use were related to emotional and physical neglect. The average CTQ values for any form of maltreatment were higher in alcohol and cocaine users – as expected, as a way to cope with the early trauma of CM. These data corroborate the findings of Banduci et al., who described an association between alcohol/cocaine use and elevated CM rates in adults. In this study, the authors observed a potential for comorbid psychiatric disorder among participants with alcohol dependence (OR 9.9), cocaine dependence (OR 5.3), or opioid dependence (OR 4.7) when compared to those with no history of CM.⁴⁰

Other studies have found that adult victims of child sexual abuse have high rates of healthcare utilization and significantly more health complaints when compared to adults with no such history,³⁰,⁴¹ in addition to higher rates of psychoactive substance use,⁶,¹⁰ resulting in increased social and health costs.³⁰ Physical and sexual abuse in childhood is a major factor for risk-taking behaviors, including substance abuse, self-harm, prostitution, and increased vulnerability to further sexual assault. High-risk behaviors, in turn, may lead to long-term physical health problems. Victims of sexual abuse, for example, may be prone to sexually transmitted infections.³⁴

There is a vast body of literature emphasizing the role of victimization during childhood, along with risk contexts such as transactional sex,⁴² compulsive sex behaviors,⁴³ and overdose risk,⁴⁴ as predictors of long term disorders, pathways to personality disorders,⁴⁵ comorbidity, suicide attempts, polydrug abuse,²⁴,⁴⁶,⁴⁷ and relapse in drug-dependent individuals over the course of their adult life.⁴⁸,⁴⁹ This shows that CM should be seriously taken into consideration when assessing the type of treatment required, as it represents a major risk factor for drug addiction and other mental disorders.⁴⁹,⁵⁰ The overlap between early trauma and later substance dependence poses a significant challenge in treatment of comorbidities.⁸,¹⁹

In our sample, one-third of drug users who reported physical abuse in childhood endorsed a SAST score of 6 points or higher, and childhood sexual abuse increased the odds of paraphilic thoughts in adulthood. As anticipated in our hypothesis, to have suffered abuse in childhood is a significant predictor of high-risk sexual behavior in adulthood. Previous evidence points out that childhood abuse potentially increases the risk for sex addiction and paraphilic thoughts in adulthood.³¹,⁵¹ This association was also observed in a study by Hall in which he assessed the childhood of sex addicts and found that 38% had been emotionally abused, 17% had been sexually abused, and 16% had been physically abused.⁵¹

Hahn et al. found that alexithymia accounted for a significant part of the relationship between CM and high-risk sexual behavior in a sample of 425 sexually active college undergraduates. Moreover, the association between alexithymia and sexual risk-taking was fully accounted for in two separate behaviors. First, negative urgency and subsequent alcohol use partially mediated the relationship, while the second outcome was accounted for by a needy interpersonal style.⁵²

All of these findings suggest the importance of assessing for childhood abuse and neglect experiences among patients with substance dependence disorder, in order to develop appropriate early intervention and harm-reduction strategies.

This study has a number of limitations. One is the self-administered nature of the instrument. This may have produced a biased interpretation, especially in a population with low educational level, such as our sample. However, investigating a history of violence and traumatic events in any population means addressing highly sensitive issues, which create embarrassment, guilt, and fear. Studies that preserve the respondents’ identity and do not result in judgment of the participants tend to generate more reliable data and benefits for those who participate.

Recall bias also may have occurred in this study, as our questionnaire assesses events that occurred in childhood. The cross-sectional nature of the study does not allow for causal inference, and – as in all observational studies – there may be some unmeasured confounders that were not captured and considered in the analysis. The literature supports a strong relationship between childhood maltreatment and mental illness, but most studies reviewed are cross-sectional and/or used recall to assess maltreatment, and are thus prone to temporality and recall bias.⁵⁰ Since a convenience sample was used, our findings cannot be generalized.

Individual consultants who have continuous contact with children, such as schoolteachers and providers in community health services, could have a leading role in recognizing, responding to, and supporting children who have experienced maltreatment. Health professionals such as nurses, dentists, doctors, and social workers should be advised to observe a child’s appearance and behavior and look for any physical or emotional signs of abuse³⁴ in various health settings, particularly addiction treatment. These findings have important implications for the daily practice of preventing child abuse. Preventing CM is not a political priority in many countries around in the world, despite the importance of this problem and increasing awareness of its high social costs.¹ Furthermore, our findings also have implications for clinical settings designed for substance dependence treatment. They may help implementation of interventional strategies by health professionals; because of the high prevalence of CM, these issues need to be addressed with a view to preventing relapse and improving prognosis.⁶,¹⁰,¹¹ Identifying and treating persons with CM may have a significant impact on public health. Our findings support the notion that substance abuse treatment should include screening for CM and integrated interventions to address common sequelae of abuse (e.g., posttraumatic stress disorder and suicide risk), as previously recommended.⁵³ Drug users with a history of CM require intensive secondary suicide prevention efforts.⁵⁴ The integration of preventive interventions within programs frequently accessed by drug users, such as community health clinics, requires increased attention, consideration, and evaluation.⁵³

CM is a human rights violation, as well as a complex public health issue. It is the most important preventable cause of psychopathology, accounting for about 45% of the population’s attributable threat for childhood-onset psychiatric disorders.⁵⁵ It is also associated with multiple adverse outcomes in adulthood, including poor mental health and violence. This has important implications for primary prevention efforts, and highlights the need for effective programs and policies to reduce its occurrence. In this context, prevention strategies should prioritize and focus on early-childhood exposure to violence in the family environment.⁵⁶ Intervening at an early stage with proper parenting programs may reduce a child’s risk of developing long-term health and psychological problems and reduce the public health burden of CM by preventing future health problems and revictimization in adulthood, along with its negative consequences, such as alcohol and drug dependence.³⁴

Research on the potential prospective impact of CM reduction on the incidence of psychiatric morbidities is scarce, and should be one of the challenges addressed in future studies.⁵⁰

In conclusion, adults with substance use problems report high rates of physical and sexual abuse in childhood, especially women. CM is associated with sexual revictimization and conditions of high-risk sexual behavior in later life, including sex addiction, paraphilic thoughts, and exchange of sexual favors for drugs.