Antisocial Personality Disorder and its Associated Factors among Incarcerated Offenders at a Maximum-Security Prison in Nigeria

Abstract

Background: 

Although previous studies from Western nations had reported elevated rates of antisocial personality disorder (ASPD) among incarcerated offenders, there are limited studies from the developing nations like ours. The study was aimed at determining the prevalence of ASPD in a prison population and its association with social and substance use variables.

Methods: 

Using a cross-sectional survey, 277 randomly selected incarcerated offenders were assessed using a sociodemographic questionnaire and Structured Clinical Interview using the Mini-International Neuropsychiatric Interview plus to assess ASPD and substance use disorders. Diagnoses were made based on the Diagnostic and Statistical Manual of Mental Disorders-4^th edition and the 10^th revision of the International Statistical Classification of Diseases and Related Health Problems.

Results: 

The prevalence of ASPD in this population of offenders was 13.5%. The most common offense was armed robbery. Offenders with ASPD were more likely to be unemployed prior to imprisonment and have a father who uses or abuses alcohol or cannabis. Significantly, those with ASPD were more likely to meet criteria for alcohol and cannabis use disorders.

Conclusion: 

There is an elevated rate of ASPD among incarcerated offenders, and such offenders need to be evaluated for alcohol and substance use disorders to ensure smooth rehabilitation.

INTRODUCTION

There is increased evidence to suggest a strong association between personality disorders and significant risks for violence.[¹²³] This group of offenders often present greater challenge in the rehabilitation of inmates.[⁴] Of the various personality disorders associated with criminal behavior, antisocial personality disorder (ASPD) has been described as one of the best predictors of criminal behavior.[⁵⁶]

According to the Diagnostic and Statistical Manual of Mental Disorders, 5^th edition (DSM-V), by the American Psychiatric Association,[⁷] personality disorders, generally, represent a significant impairment in personality (i.e. self and interpersonal functioning) that is relatively stable across the lifespan, with onset in adolescence or early adulthood. Such behavior is usually at variance with cultural norms or expectations, and often time accompanied by distress or impairment of either the individual or the people around him.[³] People with ASPD, on the other hand, present with the pattern of socially irresponsible behavior (such as violating or disregarding rights of others) alongside repeated criminal behavior, impulsivity, aggressiveness, and exploitative and guiltless behavior.[³⁸] According to the social control theory, such individuals break the law due to a breakdown with their societal bond.[⁹¹⁰] The four dimensions of social bonding, i.e. attachment, commitment, involvement, and belief, restrain individuals from satisfying their natural appetites for pleasure by becoming more sensitive to how others are affected by behaviors.[⁹] As moral codes are internalized and individuals are attached to their community, the propensity to commit deviant acts is limited. Self-control has been described as the most proximate factor to crime and deviance, and individuals with low self-control tend to seek immediate gratification, are impulsive, are self-centered, and are generally insensitive to the feelings of others.[⁹] This may explain the major features of ASPD and its relationship with criminal behaviors.

The prevalence of people with ASPD in the general population is quite low, usually between 2% and 5%.[¹¹¹²] In prison population, however, ASPD is overrepresented,[⁶¹³¹⁴] with the prevalence of people with ASPD in the criminal justice population increasing to about 50%.[¹⁵] Black et al.[⁸] reported that over 35% of newly incarcerated offenders in the USA met the criteria for ASPD,[⁸] and approximately one in two male prisoners and one in five female prisoners had ASPD, and relative to other mentally ill offenders, this group of offenders is more likely to re-offend after discharge from the prison.[⁶]

In addition, majority of the people with ASPD also meet the criteria for another psychiatric diagnosis, with up to 90% having another mental illness.[¹⁴] More importantly, ASPD is associated with significant psychosocial impairment, depression, schizophrenia and other psychotic disorders, substance misuse, borderline personality disorder, domestic violence and increased risk of suicide, and medical comorbidity.[⁸¹⁶¹⁷]

The risk for substance use disorders is often increased by the presence of ASPD.[¹⁸¹⁹²⁰] This is not limited to just those in the prison but also to those with mood disorders and schizophrenia.[¹⁸] According to Mueser et al.,[¹⁸] ASPD is strongly related to all measures of substance use problems and disorders, as well as fathers' history of substance use disorder. Among drug abusers, it has been noted that the presence of comorbid ASPD predicts criminal behavior following treatment compared with substance abusers without such a diagnosis,[¹¹²¹] however, other studies had refuted this observation.[²²²³] Alongside the challenges of substance misuse, offenders with ASPD also present with considerable management problems due to their irritability, aggression, disregard for the rights of others, and lack of remorse.

Studies looking at psychiatric morbidity among incarcerated offenders in Nigeria have reported high rates of psychiatric morbidity, with over half of the population presenting with one mental disorder or the other, most importantly substance use disorders.[¹²²⁴²⁵] This is likely because ASPD is one of the most common co-occurring psychiatric diagnoses among people with a substance use disorder.[²⁶] There are limited studies examining ASPD among incarcerated offenders in Nigeria using a structured instrument. This study aimed to determine the prevalence of ASPD and its association with social and drug use variables among inmates at a maximum-security prison in Nigeria.

METHODS

Research design

A cross-sectional survey was adopted in this study to assess inmates at the maximum-security Federal Prison in Abeokuta, Nigeria, for variables of interest.

Study population

The sample for the study was drawn from a prison population consisting of 489 awaiting trial (including 28 females) and 282 convicted inmates (including 5 females), Who were serving various prison terms at the Federal Prison, Abeokuta. Using Cochrane's minimum sample size formula,[²⁷] the estimated sample size was 286. Participants for this study population were selected using a simple random sampling, using a table of random numbers, and the probability proportional to size method was used to determine the number of participants based on their prison status, i.e., either awaiting trial or convicted inmates. An additional 10% was added to accommodate for those who may leave the prison before they were evaluated or who may decline.

Due to limited number of female inmates, they were all excluded from the study. Those with severe physically illness as well as inmates those with learning disability or those who understands neither Yoruba nor English languages were also excluded from the study.

Data collection

Each participant was interviewed with a pro forma containing information on sociodemographic variables, forensic details, and details of parental alcohol and substance use; ASPD was assessed using the Mini-International Neuropsychiatric Interview English version 5.0 (MINI plus 5).[²⁸] Similarly, alcohol abuse/dependence and other psychoactive substance use disorders were assessed using their respective modules of the MINI plus 5, a short, structured diagnostic interview, developed by psychiatrists and clinicians in the United States and Europe, for evaluating psychiatric disorders based on the DSM-IV and the 10^th revision of the International Statistical Classification of Diseases and Related Health Problems criteria. Validity and reliability studies comparing the Structured Clinical Interview for the DSM-IV (SCID-IV) and the Composite International Diagnostic Interview with the MINI plus 5 show high validation and reliability scores (kappa scores for all diagnoses were above 0.70, with about 70% being above 0.90, indicating high interrater reliability) and in comparison with the SCID-IV, its sensitivity is above 0.70 and specificity is 0.85 and above for most diagnoses.[²⁸²⁹]

Statistical analysis

Data generated from the questionnaires were analyzed using Statistical Package for the Social Sciences program version 18 (IBM Corporation, Armonk, New York, USA). Presentations of data were done using frequency distribution tables or chart; univariate analysis using t-test was employed for continuous variables, whereas Pearson's Chi-square test was used for qualitative variables with Fisher's exact or Yate's correction applied, as applicable. This analysis has been removed during the course of revision, thus the statement was no longer necessary. The level of significance was set at 5%.

Ethical considerations

All procedures performed in study were in accordance with the ethical standards of the institutional Ethics and Research Committee of the Federal Neuropsychiatric Hospital, Aro, Abeokuta, and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Official permission was granted by the Controller of Prisons, Ogun State Command. A written informed consent was obtained from all the participants after informing them about the research aims and objectives. Confidentiality and privacy of information were ensured. The participants were also assured of that their choice of participating or not will not affect their trial, sentence, or treatment by the prison staff in anyway.

RESULTS

General measures

A total of 277 inmates finally participated in the interview. Of these, 169 (61.0%) were awaiting trial, whereas 108 (39.0%) were convicted of various offenses. The mean age of the participants was 34.77 ± 10.28 years. Majority of the participants had some level of primary or high school education (75.45%) and were employed (88.1%) prior to imprisonment. Those who were convicted were serving time-specific imprisonment (27 [9.7%]), life imprisonment (21 [7.6%]), or were sentenced to death (60 [21.7%]). Twelve (4.3%) of the 277 inmates had previous imprisonment, of which 3 (25.0%) had ASPD. Seven (2.6%) of the inmates had a family history of imprisonment, with first-degree relatives in 3 (1.1%) and second-degree relatives in 4 (1.5%) inmates.

Type of inmates' offenses

Among these offenders, armed robbery was the most common offense either charged with or convicted of, accounting for 153 (55.2%) of the inmates. This was followed by murder, stealing, fraud, rape, and kidnapping, representing 53 (19.1%), 28 (10.1%), 11 (4.0%), 7 (2.5%), and 6 (2.2%) of the cases, respectively. Other offenses were manslaughter in 4 (1.4%); illegal possession of firearms, assault, and conspiracy, each representing 1.1%; fighting in 2 (0.7%); and drug trafficking, impersonation, bribery, and aiding and abetment, each representing 0.4% of the inmates.

Types of offense and antisocial personality disorder

Table 1 shows the relationship between the types of offense and ASPD. The rate of ASPD was highest among those charged with armed robbery (19.5%), followed by rape and stealing accounting for 16.7% and 11.1%, respectively. The proportions of ASPD in relation to other offenses are shown in Table 1.

Table 1: Proportion of antisocial personality disorder in various offenses

Antisocial personality disorder and inmates' sociodemographic characteristics

Table 2 shows the relationship between inmates' sociodemographics and ASPD. Higher proportions of those who were not employed prior to their incarceration (8 [24.2%]) compared with those who were employed (29 [11.9%]) had ASPD (P = 0.050). Twenty-four (17.7%) of the inmates whose fathers were alive compared with 12 (9.22%) of those whose fathers were dead had ASPD (P = 0.039). Similarly, those whose fathers use/abuse alcohol or cannabis were more likely to have ASPD (P = 0.033). There was no statistically significant relationship between ASPD and other sociodemographic variables (P > 0.05).

Table 2: Relationship between sociodemographic variables and antisocial personality disorders

Antisocial personality disorder and alcohol and substance use disorders

Table 3 describes the relationship between alcohol use disorders (AUDs) and drug use disorders and ASPD. A greater proportion of those who met the criteria for current AUDs (37.5%) compared with those who did not (11.9%) had ASPD, and this is statistically significant (P = 0.030). Similarly, those who met the criteria for a lifetime AUDs, lifetime and current cannabis use disorders (CUDs) were more likely to have ASPD (P < 0.05). The relationship between other substances and ASPD is shown in Table 3.

Table 3: Antisocial personality disorder in relation to alcohol and substance use disorders

DISCUSSION

In this study, we examined ASPD and its associated factors among incarcerated offenders in a maximum-security prison in Nigeria. The prevalence of ASPD in this population of offenders was 13.4%, which was relatively lower than 18% and 19.2% earlier reported in Nigeria and India, respectively.[¹²¹³] In Brazil, about twice this value (26.9%) was reported by Pondé et al.[³⁰] among 497 prisoners studied using the Portuguese version of the MINI. In the USA, on the other hand, Black et al.[⁸] reported a prevalence of 35.3% among randomly selected prisoners using the same instrument. Although similar instrument was used in these studies, other background characteristics such as nature of the prison, the presence of other psychiatric disorders, and the prevalence of ASPD in the general population studied may possibly explain these variations. Nevertheless, one common feature is that the prevalence of ASPD is quite higher compared with that of the general population from which the prisoners were drawn.[³¹]

The relatively higher proportion of people with ASPD in the prison relative to the general population may be due to the fact that people with ASPD are likely to commit crime,[⁵⁶] and consequently apprehended and imprisoned. Besides, the higher prevalence can be explained based on the disinhibition theory.[³²] Exposure to inhumane condition of the prison and repeated exposure to aggressive behavior from other prisoners lead to loss of normal restraints; as a result, aggressive behavior becomes normalized with alteration in the norm-governing behavior. With this, aggression and other antisocial behaviors are seen as norms in certain circumstances among incarcerated offenders.

With respect to the offenses committed, armed robbery was the most common offense, accounting for over half of the total offenses. Of these, a higher proportion had an ASPD compared with the proportions of ASPD in other offenses. Studies have shown that people with serious mental illness have significantly higher rates of both violent and serious nonviolent misconduct.[³³] This may possibly explain why a relatively higher proportion of offenders with ASPD were found among those charged with armed robbery, rape, and murder. However, ASPD has been shown to moderate the relationship between serious mental illness and serious nonviolent charges, but not the relationship between serious mental illness and violent charges.[³³]

Most of the sociodemographic characteristics of the inmates do not predict ASPD; however, when compared with those without ASPD, a majority of those with ASPD were unmarried and were not employed prior to incarceration. Marriage has been described as a moderating variable. As noted in a review by Black,[⁴] being married aids the improvement of antisocial symptoms. It has been shown that ASPD alongside other cluster B disorders was more prevalent in men, separated or divorced, and those from lower social class.[¹⁰] Similarly, offenders whose parents abuse alcohol or other substances of abuse were four times more likely to be diagnosed with ASPD than those whose fathers did not. As reported by earlier studies, there is an increased rate of mental disorders or presence of psychopathology among children of parents with substance use disorders.[³⁴³⁵³⁶] The prevalence of some specific mental disorders such as conduct disorder, attention deficit hyperactivity disorder (ADHD), major depressive disorder, and anxiety disorders has been observed to be higher among children of parents with substance use disorders than those whose parents do not abuse substances.[³⁴] As noted by Clark et al.,[³⁷] parents with substance use disorders often have other mental disorders similar to those found in their children.

Oftentimes, those parents have childhood histories of conduct disorder, ADHD, major depressive disorder, or anxiety disorders. This may explain the association between parental substance use and ASPD observed in this study.

In this study, significantly higher rates of offenders with ASPD met the criteria for substance use disorders, notably AUDs and CUDs. ASPD has been shown to be a significant risk factor for AUDs and other substance use disorders, not just in the prison,[^{1819202638394041}] but also among patients with either mood disorders or schizophrenia.[¹⁸] Among drug abusers, the presence of comorbid ASPD tends to predict criminal behavior following treatment.[²²¹] As reported by Fridell et al.,[¹³] offenders with a diagnosis of ASPD, based on clinical observation, were substantially more criminally active than substance abusers without such a diagnosis. This may account for the association between ASPD and substance use disorders noted in this study and the elevation of both ASPD and substance use disorders in the prison compared with the general population. Substance abusers diagnosed with ASPDs were twice more likely to be charged with theft only[¹¹] and about two and half times more likely to be charged committing multiple types of crime during an observational year.[⁴²] In contrast, some studies had refuted the association between criminality and ASPD.[²¹²²²³] Reporting or publication bias could possibly account for these inconsistent findings.

In this population of offenders, nearly half of the inmates with ASPD met the criteria for lifetime CUDs and over 50% of those with the diagnosis of ASPD met the criteria for current CUDs. In a study looking at cannabis use and CUDs among people that were mentally ill,[⁴³] cannabis use and CUDs were particularly associated with bipolar disorder, substance use disorders, and personality disorders, especially antisocial, dependent, and histrionic personality disorders. In their study, persons with a mental illness in the past 12 months represented 72% of all cannabis users. Similarly, in a population-based study, personality disorders were found to explain a higher part of variance in problematic cannabis use symptoms in adolescents, and individual differences in the liability to cannabis use and CUDs appeared to be linked to genetic risks correlated with antisocial and borderline personality disorder traits.[⁴⁴]

CONCLUSION

The prevalence of ASPD among incarcerated offenders in this study was higher than those reported for most general populations and relatively lower compared with those reported in other prisoners' population elsewhere. Among this population, the diagnosis of ASPD is associated with fathers' substance use, fathers being alive, current or lifetime AUDs, and current or lifetime CUDs. There is an elevated rate of ASPD among offenders in this prison population, and offenders with ASPD are more likely to have substance use disorders including alcohol while in the prison, therefore there is a need for adequate intervention and rehabilitation programs that should address ASPD, AUDs, and substance use disorders among offenders.

Limitations

There are some limitations to the current study. First, the sample was limited to offenders from a single prison, thus making it difficult to extrapolate the findings to the general prison population. Again, the participants need to recall past drug usage, which may affect the accuracy of the information given. In addition, disclosing information about alcohol and other illicit drugs in prison is considered an offense, and this may affect the extent to which inmates reported their substance use. However, with the assurance of confidentiality of the information given, this, we believe, should limit the extent of distortion of the information given. The strength of this article is that it is one of the few studies; if not, the first on ASPD from the most populated African country and even from this continent.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Acknowledgments

We acknowledge the support of federal prison's staff at Abeokuta, Ogun State, Nigeria, during data collection.