Exposure to physical and sexual violence and suicidal ideation among schoolchildren Exposição à violência física e sexual e ideação suicida entre escolares

Objective: The purpose of this study was to estimate the association between exposure to physical and sexual violence, and suicidal ideation in Brazilian Schoolchildren, accounting for confounding variables of religious practice, and problems with alcohol and other drugs. Methods: This study consists of a cross-sectional analytical approach of a larger school-based study conducted in 2012 in two medium-sized municipalities in south of Brazil. Participants were 3,547 students aging 12 to 17 years old who answered an assembled questionnaire. Descriptive and Logistic Regression analyses were conducted with suicide ideation outcome testing prediction models stratified by sex. Results: Suicide ideation prevalence in the sample was of 21.7%, and regression analysis indicated that girls and boys exposed to physical or sexual violence had 3.42 and 3.14 times more probability of referring suicidal ideation in the past 30 days. Adjusted analyses showed little interference of religious practice, while problems with alcohol and other drugs seemed to also explain suicidal ideation in the sample. Conclusion: We highlight the importance of future longitudinal studies to investigate the mechanisms through which exposure to physical or sexual abuse influence suicidal ideation among boys and girls, as well as mediation studies that could enlighten the role of drug and alcohol use in this relationship.


INTRODUCTION
Among many public health problems discussed and faced nowadays, suicide has been one of the main concerns 1,2 .According to the World Health Organization (2012), in 2012, 804,000 people in the world died because of suicide, which accounted for 50% of male and 71% of female violent deaths.Globally, suicide is among the three leading causes of death in the 15-44 years old age group, and the second most frequent cause of death in the 15-19 years old age group 3 .
In the years of 1994 to 2004, suicide rates in Brazil were between 3.9 to 4.5 people per 100,000 inhabitants, placing Brazil in the list of countries with the lowest rates.However, due to its numerous population, Brazil was among the first 10 countries with the highest absolute number of suicide occurrences, and some of its states presented rates as high as those in countries displaying medians to high rates 4 .For instance, in the year of 2004, the Brazilian Southern state of Rio Grande do Sul was the one with the highest rate of suicide [5][6][7] , considering that 9.88 people for every 100,000 inhabitants died from it 3 .
In the last 45 years, a global increase in the occurrence of suicide among youth has been observed 4,8 , supporting data indicating it as one of the main contributors to mortality rates during adolescence 9 .The possibility of young people manifesting suicidal thoughts and behavior grows exponentially after their transition from childhood to adolescence 10 .A systematic review including 128 studies investigating suicide in adolescence reported that 9.7% of the adolescents in the studies' samples had already tried suicide during their lifetime, and 29.9% had already thought about it at some point 11 .
The main predictor of self inflicted acts with intention to die, defined as suicidal behaviors, is suicidal ideation, which refers to thoughts of wishes, attitudes and plans about dying 7,10,12,13 .It is estimated that 33.4% of adolescents having suicidal thoughts develop a suicide plan, and 33,9% attempt to it 14 , supporting suicidal ideation as one of the most important risk indicators of reaching suicide as an outcome 15 .
The frequency and intensity of suicidal thoughts increase according to age, especially after the first years of adolescence 7,10,14 , and besides contributing to lethal consequences, its occurrence during this developmental stage may produce negative lifetime outcomes 15 .Therefore, comprehending factors related positively and negatively to suicidal ideation allows the development of interventions oriented to the most relevant factors for preventing, identifying and treating suicide.
Socio-demographic and individual factors, as well as adverse family environments and negative experiences during childhood, are considered risk factors for the triggering of suicidal ideation during adolescence 16 .Among the great amount of discussion regarding suicidal behavior and ideation risk and protective factors, some associations stand out.Higher rates of suicide are registered among girls when compared to boys 10,12,14 , among adolescents who are exposed to physical and sexual violence [17][18][19] , who come from dysfunctional families with histories of psychopathology, and alcohol and drugs abuse 7,9,16 , and who abuse of alcohol and other drugs 12,20,21 .On the other hand, many studies have suggested that attending to religious institutions, being more exposed to religious beliefs, and paying more importance to religion reduces the chances of suicidal ideation, suicide attempts, and suicide itself [22][23][24][25][26][27] .
Available data indicates direct associations between physical and sexual violence, and suicidal thoughts in adolescents 11,17,19,28,29 .Physical and sexual abuse during childhood was found to be strongly associated with suicidal ideation in adolescents even when socio-demographic, mental health, and family variables that could influence this relationship are accounted for 17 .Results from previous studies state that sexual abuse victims show 2 to 3 times more risk of presenting suicidal ideation as a symptom 18 , and that physical abuse is a significant predictor of suicidal ideation also when confounding variables are controlled 28,29 .
Unfortunately, many Brazilian children and adolescents are exposed to violence and abandonment during their lifetime, having to face several types of physical, social, cultural and racial aggression every day 30  Grande Sul is the Brazilian state with the highest suicide rates, the present study aims to estimate the association between exposure to physical and sexual violence, and suicidal ideation in southern Brazilian Schoolchildren.

METHODS
This paper consists of a cross-sectional analytical approach of a larger school-based study.The research was conducted in every school in the cities of Lajeado and Sapiranga, both medium-sized cities located in the countryside of the Brazilian state of Rio Grande do Sul, in the year of 2012.

Participants
Participants were 3,547 students aging 12 to 17 years old who were randomly selected.Random sampling was carried out by every school's classes, preserving the sample's proportionality by gender, age, sex, and school system (public, or private) in which the adolescents were enrolled.

Procedures
After both municipalities' departments of education approvals, representatives from each school held the responsibility to make available for the students' guardians the information about the objectives, data collection procedures and ethical implications of the presented study.Special attention was given to the knowledge that the questionnaire used was one of self-report and that the anonymity of those who answered it, as well as those who did not, would be preserved.Informed Consents were distributed and collected by the school before data collection, and the students who did not have the authorization from their guardians, or who did not wish to participate, were instructed to receive the questionnaire and return it blank, therefore avoiding the identification of the non-respondents within the classroom.
Data collection occurred in 214 classrooms in the city of Lajeado, and 75 in the city of Sapiranga.All the students returned the questionnaires to urns especially prepared for this study after filling them out.After the questionnaires were handed in, these urns were sealed and were opened only in a reserved room used for data typing and processing.The students who were unable to answer the questionnaire because of physical, or cognitive deficiency were not asked to participate.
To assure quality, data collection process was assisted in person by trained field supervisors, and all classrooms' visits were scheduled previously.The research projects related to the data collection described were approved by the Ethics Committee of the University of Vale do Rio dos Sinos (Unisinos) prior to execution thereof, under the protocols 074/2011 and 028/2012.

Instruments
The selected variables for this analytical study were extracted from sociodemographic and dichotomous questions of a questionnaire that was developed for an extensive school-based investigation about the use of psychoactive substances among students, as well as associated conditions.The questionnaire was created based on other studies' instruments 32,33 and has been standardized and pre-tested before use.

Data analysis
Data were entered in the software EpiData 3.5 by double entry for checking and correcting typos.Inconsistencies identification and correction were performed after a first round of analyzes.Altogether, 9.4% of losses or refusals were computed.Data analysis was conducted using Logistic Regression.Reporting suicidal ideation in the last 30 days (dichotomous, thought about ending his or her life: yes or no) was taken as the outcome variable of this investigation.The exposure variables were life history of any kind of physical or sexual violence (both dichotomous, experience of physical violence in your life: yes or no, or experience of sexual abuse in your life: yes or no).The estimated design effect according to school for the outcome suicidal ideation was 1.48, justifying this effect control in subsequent analysis.
Despite no significant interaction was found between the variable sex and each one of the independent variables reporting life history of violence, neither in multiplicative scale (physical violence: p = 0.689 and sexual violence: p = 0.330) nor in additive scale (physical violence: p = 0.101 and sexual violence: p = 0.332), it has been decided to proceed stratified analysis considering specific behaviors of the outcome according to sex.Therefore, two prediction models were tested taking into account some confounding variables.The confounding variables were selected from the literature and were included in the model in an order that considered socio demographic and family context variables, potentially protective factors related to cultural behaviors, or standards, and suicidal ideation identified risk factors beside the proposed exposure variables.
To decide the prediction model of suicidal ideation for boys and girls the confounding variables were tested for associations with the outcome among boys and girls.The potentially confounding variables taken were: age (ordinal categorical: from 12 to 14 years old, and from 15 to 17 years old), responsible guardian education 14 [ordinal categorical: illiterate or no more than the Elementary School (ES) fourth grade; Between the ES fifth and seventh grade; Complete Elementary School; Complete High School (HS); Complete Higher Education (HE)], religious practice (dichotomous, attend or worship religious practices regularly yes or no) habit of praying (dichotomous, usually pray when having problems yes or no), and use of alcohol, tobacco or illicit J Bras Psiquiatr.2017;66(2):96-103 Violence exposure and suicidal ideation drugs in the last year (dichotomous, yes or no) and problems with alcohol and drugs at home (dichotomous, yes or no).The confounding variables were only included in the models if the were significantly associated with the outcome suicidal ideation at a p < 0.002.
Therefore, the prediction model of suicidal ideation using physical, and sexual abuse as the exposure variables for girls was adjusted for responsible guardian education, religious attendance and praying habit, and use, or family problems with alcohol and other drugs.On the other hand, the same prediction model for boys was adjusted for religious attendance and praying habit, and use, or family problems with alcohol and other drugs.

RESULTS
The study sample consisted of 3,547 students, 54.2% of those were female and the mean age was 14 years old (sd = 1.7).From all students, 137 (3.9%) did not answer the question about suicidal ideation in the last month, therefore, from the 3,410 respondents, 739 [P = 21,7% (CI95%: 20.3% -23.1%)] reported having thought about ending their own lives during the last 30 days prior to data collection.The absolute and relative sample distributions of this study's interest variables, as well as the prevalence of suicidal ideation according to these variables, are presented in Table 1 for girls and Table 2 for boys.Among girls, suicidal ideation prevalence was significantly higher among participants whose responsible guardian education was Elementary or less (p = 0.007), who have had alcohol, or drug problems at home (p < 0.001), who used alcohol (p < 0.001), Tabaco (p < 0.001) and illicit drugs (p < 0.001) in the past year, who haven't attended any religious practice (p < 0.001) and haven't had the habit of praying (p = 0.001), as well as those who have been exposed to physical (p < 0.001) and sexual abuse (p < 0.001).Among boys, suicidal ideation prevalence was significantly higher among participants who have had alcohol, or drug problems at home (p = 0.003), who used alcohol (p = 0.001), Tabaco (p = 0.007) and illicit drugs (p < 0.001) in the past year, who haven't attended any religious practice (p = 0.044) and haven't had the habit of praying (p = 0.003), as well as those who have been exposed to physical abuse (p < 0.001).The variable age was not significantly related to suicidal ideation neither for girls (p = 0.212), nor boys (p = 396).Besides, for boys, neither responsible guardian education (p = 0.591), nor exposure to sexual abuse (p = 0.112) was significantly associated with suicidal ideation.
Results from the regression analysis stratified by sex are presented in Table 3 for girls, and Table 4 for boys.Regression analysis to estimate suicidal ideation prevalence ratios related to exposure to physical or sexual violence in the whole sample are presented in Table 3. Analysis indicated that those girls who have been exposed to physical abuse throughout their lifetime had 3.42 times more probability of referring suicidal ideation in the past 30 days previous to data collection [OR = 3.42 (CI95%: 2.49 -4.69), p < 0.001], and those who had been exposed to sexual abuse had 3.36 times more probability of referring suicidal ideation within the same time range [OR = 2.11 (CI95%: 2.04 -5.52), p < 0.001].When adjusting the analysis to responsible guardian education, and to attendance of any religious practice and praying habit, the odds ratios show subtle alterations for both, physical [OR = 3.13 (CI95%: 2.19 -4.48), p < 0.001] and sexual abuse exposure [OR = 2.89 (CI95%: 1.72 -4.86] p < 0.001], suggesting that these variables slightly interfere in the exposure to violence observed effect over the occurrence of suicidal ideation in the past 30 days.On the other hand, when adjusting the analysis to individual, or family problems with alcohol and other drugs, a higher reduction of the odds ratio was perceived among girls who had been exposed to physical [OR = 2.53 (CI95%: 1.71 -3.74), p < 0.001] and sexual abuse [OR = 2.57 (CI95%: 1.40 -4.69), p < 0.001].
Among boys, results are very much alike for those who have been exposed to physical violence, suggesting that those boy have 3,14 times more probability of reporting suicidal ideation in the past 30 days previous to data collection [OR = 3.14 (CI95%: 2.45 -4.03), p < 0.001].When adjusting to religious attendance, and praying habit, the odds ration presents a subtle decrease [OR = 3.10 (CI95%: 2.39 -4.02), p < 0.001], while adjusting to use, or family problems with alcohol and other drugs as well shows a more expressive odds ration decrease [OR = 2.83 (CI95%: 2.12 -3.78), p < 0.001].It is important to notice that exposure to sexual abuse was not a significant predictor of suicidal ideation among boys.Results of the adjusted analysis suggest that religious practice might not be a sufficient protective factor against suicidal ideation in the sample, and that part of the effect over suicidal ideation that seemed to be due to the exposure to violence may be explained by individual or family problems with substance use.

DISCUSSION
Our results show that the prevalence of suicidal ideation in the last month reported by the sample (21.7%) is consistent 11,34 , and higher 12,14,15 than results already found in community and school based samples of adolescents between 11 and 20 years old.Altogether, these data support the increased possibility, already reported 10 , of young people manifesting suicidal thoughts after their transition from childhood to adolescence.
The main purpose of this study was to estimate the association between exposure to physical, or sexual violence, and suicidal ideation in a Brazilian adolescent school based sample.Results from crude analysis stratified by sex point out to a significant association, in which girls who have been physically and sexually abused present, respectively, 3.42 and 3.36 more probability of reporting suicidal ideation in the last month, and boys who have been exposed to physical abuse present 2.11 more probability of reporting the same outcome.These findings are somewhat consistent with what is found in the literature suggesting that physical 28,29 abuse is an important predictor of suicidal ideation among female and male, and that sexual abuse 35 is an important predictor of suicidal behavior among girls.
These results express differences between type of abuse exposure between boys and girls with higher prevalence of sexual abuse among girls, and higher prevalence of physical abuse among boys.For this sample, sexual abuse was not a significant predictor of suicidal ideation among boys, even though the prevalence of the outcome was higher among those boys who had been exposed to sexual abuse.Exposure to both types of abuse has already been associated with higher risk for mental disorders, including suicidal ideation, between 16 and 25 years old 36 of both sexes.It is believed that because of the few occurrences of sexual abuse among boys, no associations with the outcome were possible to be estimated precisely.
Even though the association between exposure to abusive experiences and suicidal ideation is already established in the literature, little is know about the mechanisms through which these experiences lead to suicidal behavior.From a neurodevelopmental perspective, these experiences carry the potential to cause disruptions and neurological scars because, in order to deal with highly stressful environments during development, individuals have to modify the psychological and neurological structure and function to adapt to these environments.The result of these disruptions and adaptations is what makes individuals more prone to developing certain types of psychopathology and symptoms 37 .Besides, these experiences generate intense stress reactions that, when repeated, lead individuals to become chronically stressed and overly vigilant, presenting an atypical cortisol regulation 35 .Even though there is data regarding the impact of repeated exposure to abusive experiences on healthy development, this study did not collect detailed data about the sample's frequency of exposure to physical or sexual abuse.
Moreover, it is suggested that painful and provocative experiences, such as abusive ones, confer increased risk for suicidal behavior through emotional states of burdensomeness and disconnection 38 .Such experiences may drive children and adolescents to hopelessness, or in other words, to a negative cognitive system of beliefs and expectations about the future.Hopelessness, by its turn, has already been associated with suicidal ideation, as well as connected with children maltreatment 39 .
Because exposure to violence is only one among many factors that might contribute to suicidal behavior or ideation in adolescents 11 , socio-demographic, religiosity, and drug use confounding variables were included in the analyses to examine their effect over this relationship.The sociodemographic variable of guardian education among girls, as well as religious attendance and praying habit among girls and boys had very subtle effects over the mentioned relationship.On the contrary, use of alcohol and drugs by family or by the adolescent considerably reduced the probability of reporting suicidal ideation among those adolescents physically, or sexually abused suggesting that those kind of problems might increase the risk of suicidal ideation among the adolescents who hadn't been exposed to physical and sexual abuse.
Differently than what was expected, religious practice and the habit of praying slightly influenced the magnitude of the relationship between exposure to physical and sexual abuse and suicidal ideation, as it is suggested by the comparisons of the crude and adjusted analyses confidence intervals and the estimated prevalence ratios shown on Table 3.Even though a small reduction in the estimated odds ration is observed when religious attendance and praying habit are included, a more expressive decrease is only seen when use or family problems with alcohol and other drugs are included in the model.One of the possible reasons for that is that religiosity variables may have a protective effect over suicide attempts, which was not evaluated in this study, but not suicidal ideation.Rates of suicidal attempts have already been shown to be lower in religious groups when compared to non-religious groups, while suicidal ideation rates remained similar 40 .
On the other hand, the individual or family problems with alcohol and other drugs effect observed over the already mentioned relationship suggests that part of the effect previously thought to be from exposure to physical or sexual violence over suicidal ideation may be due to individual or family use of alcohol and other drugs.It is already documented that levels of alcohol and other drugs use show increases with adolescents exposure to violence 41  Even though both conditions show predictive effects of suicidal ideation, the question of whether use of alcohol and drugs increases exposure to violence, or exposure to violence increases use of alcohol and drugs remains.Besides, parental use of alcohol and drugs has already been investigated as a moderator of the relationship between exposure to physical and sexual assault and psychiatric functioning, including major depressive episodes and adolescent substance use 42 .When testing for depressive episodes and adolescent use of substances as outcomes, significant interactions were found between parental substance use and physical and sexual assault, suggesting that parental alcohol and drug abuse may intensify the risk of poor psychological outcomes, such as suicidal ideation, for violence-exposed adolescents 42 .Further research is warranted to understand the direction of the relationship between adolescents substance use and exposure to violence, and whether parental drug use may lead to more violence exposure, and it is this violence exposure that leads to adverse outcomes.
Additionally, based on current evidence, family substance use is associated with suicidal ideation 16 , as well as lifetime substance use is associated with suicidal ideation [43][44][45] and sexual abuse.In fact, substance use can be, at the same time, a consequence of sexual abuse, and a risk factor for suicidal behavior 18 .This type of behavior is significantly more common among drug users than in the general population, and sexual, physical, and emotional abuse confer important risk of repeated suicidal behavior within this population 44 .
The results of this study should be interpreted with caution because some of its limitations.Because of the study cross sectional design, no casual, mediated, or moderated relationships can be established among the variables.At the same time, the results cannot be generalized due to the sample's non-representative characteristics.It is know that suicidal behavior is a multifactorial phenomenon with many psychological, social, biological, and environmental variables that may contribute to its occurrence 9 , and not all of them could be controlled in the present study.For instance, since it was not the scope of this article, psychopathology levels were not controlled and accounted for, even though they might influence suicidal behavior.
It is also important to consider that the only source of information about exposure to physical or sexual abuse was the adolescents who participated and answered a selfreport questionnaire investigating the interest variables through "yes" or "no" questions.Every individual is subjected to memory distortions, either through the creation of false memories, or through the sub estimation of violent experiences caused by difficulties in comprehending, or recognizing violent actions.Moreover, subjective reports of abuse may be influenced by inconsistencies in what defines physical or sexual abuse, what means that individuals can have different comprehensions, or thresholds, for what they consider abusive experiences 43 .Additionally, even though it is known that there are many variables related to the exposure to adverse events that may impact levels of psychiatric symptoms, it was not possible to collect information about the frequency, duration, or age of the exposure to these events, as well as information about who was the aggressor.
Furthermore, the severity of these experiences was not possible to be controlled, even though its influence on different negative consequences is already reported 38 .In the analyses, physical and sexual abuse were not independently analyzed, so this study is unable to suggest which form of abuse can be more important for suicidal ideation occurrence.There is evidence that only sexual, but not physical abuse, is associated with suicidal behavior 35 at the same time as there is evidence that both types of abuse can predict suicidal behavior 16,46 .
Finally, we highlight the importance of future longitudinal studies to investigate the mechanisms through which exposure to physical, or sexual abuse influence suicidal ideation differently among girls and boys, as well as mediation, or moderation studies that could enlighten the role of drug and alcohol use, and other variables, in this relationship.We also suggest that future studies evaluate severity of exposure to physical and sexual abuse, and investigate their prediction of suicidal ideation independently.
. Between 2003 and August 2011, the Brazilian Presidency Human Rights Ombudsmen (Ouvidoria de Direitos Humanos da Presidência da República do Brasil -SDH/PR) received 195,932 complaints about children and adolescents' rights violation at a rate of 209 of these complaints registered every day during January to August 2011 31 .Considering the predictive association between exposure to violence and suicidal ideation, comprehending the strength of this relationship in Brazilian samples can aid suicide prevention programs, as well as interventions.Furthermore, considering that Rio J Bras Psiquiatr.2017;66(2):96-103 Schäfer JL et al.

Table 1 .
Absolute (n) and relative (%) sample distribution and Prevalence of Suicidal Ideation (P) according to life history of physical and sexual violence, and other independent variables among schoolgirls, Southern Brazil, 2012(N = 1924) * Preceded analysis controlling the design effect by the variable school.

Table 2 .
Absolute (n) and relative (%) sample distribution and prevalence (P) of suicidal ideation according to life history of physical and sexual violence, and other independent variables among boys, Southern Brazil, 2012 (N = 1623) * Preceded analysis controlling the design effect by the variable school.

Table 3 .
Odds ratios (OR) and respective confidence intervals of 95 % (IC95%) for suicidal ideation according to life history of exposure to physical and sexual violence, among 12-17 years old schoolgirls from southern Brazil, 2012(N = 1924)

ideation among schoolchildren once exposed to Crude analysis* Adjusted to responsible guardian education* Adjusted to previous + religious attendance and praying habit* Adjusted to previous + use or family problems with alcohol and other drugs*
* Preceded analysis controlling the design effect by the variable school.** p < 0.001.*** p < 0.05.

Table 4 .
Odds ratios (OR) and respective confidence intervals of 95 % (IC95%) for suicidal ideation according to life history of exposure to physical and sexual violence, among 12-17 years old school boys from southern Brazil, 2012 (N = 1623)

ideation among schoolchildren once exposed to Crude analysis* Adjusted to religious attendance and praying habit* Adjusted to previous + use or family problems with alcohol and other drugs*
* Preceded analysis controlling the design effect by the variable school.** p < 0.001.J Bras Psiquiatr.2017;66(2):96-103 Violence exposure and suicidal ideation