Aggressive responding of male heroin addicts under methadone treatment: psychometric and neuroendocrine correlates

Evaluation of Serum Cortisol Levels and Response to Cosyntropin Test in Methadone-treated Opium Addicts

Background

Opium has been used for thousands of years for medical and analgesic purposes, and its misuse has also increased in recent years. Methadone, a synthetic opioid, has been used as an analgesic and to help patients quit opium addiction. However, some evidence suggests that long-term use of opioids can affect the hypothalamic-pituitary-adrenal axis.

Objectives

We aimed to evaluate the serum cortisol level and response to the cosyntropin stimulation test in opium addicts on methadone treatment.

Methods

The study was conducted in November 2019 at Imam Reza Hospital Rehab Center, Birjand, Iran. Thirty-eight methadone-treated opium addicts participated in the study. A blood sample was initially obtained, then 250 µg intramuscular cosyntropin was injected. After 30 and 60 minutes, two other blood samples were obtained. The data were analyzed using SPSS.

Results

There was a significant difference between serum cortisol levels and the normal value in methadone users (9.46 ± 5.42 vs. 14 µg/dL) (P < 0.001). The mean response to the cosyntropin stimulation test in methadone users was 9.34 ± 8.11 µg/dL. Also, 55% of the participants had adrenal insufficiency.

Conclusions

Serum cortisol levels significantly differed from normal values in methadone-treated patients. Therefore, we recommend measuring serum cortisol levels in methadone-treated patients before major medical procedures to consider the stress doses of corticosteroids.

Reactive vs proactive aggression: A differential psychobiological profile? Conclusions derived from a systematic review

INTRODUCTION

Scholars have established subcategories of aggressive behavior in order to better understand this construct. Specifically, a classification based on motivational underpinnings makes it possible to differentiate between reactive and proactive aggression. Whereas reactive aggression is characterized by emotional lability, which means it is prone to impulsive reactions after provocation, proactive aggression is driven by low emotionality and high levels of instrumentality to obtain benefits. Some authors have conceived these two types as having a dichotomous nature, but others argue against this conceptualization, considering a complementary model more suitable. Hence, neuroscientific research might help to clarify discussions about their nature because biological markers do not present the same biases as psychological instruments.

AIM

The main objective of this study was to carry out a systematic review of studies that assess underlying biological markers (e.g., genes, brain, psychophysiological, and hormonal) of reactive and proactive aggression.

METHODS

To carry out this review, we followed PRISMA quality criteria for reviews, using five digital databases complemented by hand-searching.

RESULTS

The reading of 3993 abstracts led to the final inclusion of 157 papers that met all the inclusion criteria. The studies included allow us to conclude that heritability accounted for approximately 45% of the explained variance in both types of aggression, with 60% shared by both, especially, for overt and physical expression forms, and 10% specific to each type. Regarding allelic risk factors, whereas low functioning variants affecting serotonin transport and monoaminoxidase increased the risk of reactive aggression, high functioning variants were associated with proactive aggression. Furthermore, brain analysis revealed an overlap between the two types of aggression and alterations in the volume of the amygdala and temporal cortex. Moreover, high activation of the medial prefrontal cortex (PFC) facilitated proneness to both types of aggression equally. Whereas stimulation of the right ventrolateral (VLPFC) and dorsolateral (DLPFC) reduced proneness to aggression, inhibition of the left DLPFC increased it. Finally, psychophysiological and hormonal correlates in general did not clearly differentiate between the two types because they were equally related to each type (e.g., low basal cortisol and vagal variability in response to acute stress) CONCLUSIONS: This study reinforces the complementary model of both types of aggression instead of a dichotomous model. Additionally, this review also offers background about several treatments (i.e., pharmacological, non-invasive brain techniques…) to reduce aggression proneness.

Prevalence and correlates of aggressive behavior in psychiatric inpatient populations

Aggressive behavior in patients with psychiatric disorders is attracting increasing research interest. One reason for this is that psychiatric patients are generally considered more likely to be aggressive, which raises a related question of whether diagnoses of psychiatric disorders predict the prevalence of aggressive behavior. Predicting aggression in psychiatric wards is crucial, because aggressive behavior not only endangers the safety of both patients and staff, but it also extends the hospitalization times. Predictions of aggressive behavior also need careful attention to ensure effective treatment planning. This literature review explores the relationship between aggressive behavior and psychiatric disorders and syndromes (dementia, psychoactive substance use, acute psychotic disorder, schizophrenia, bipolar affective disorder, major depressive disorder, obsessive-compulsive disorder, personality disorders and intellectual disability). The prevalence of aggressive behavior and its underlying risk factors, such as sex, age, comorbid psychiatric disorders, socioeconomic status, and history of aggressive behavior are discussed as these are the components that mostly contribute to the increased risk of aggressive behavior. Measurement tools commonly used to predict and detect aggressive behavior and to differentiate between different forms of aggressive behavior in both research and clinical practice are also reviewed. Successful aggression prevention programs can be developed based on the current findings of the correlates of aggressive behavior in psychiatric patients.

Dispositional Mindfulness and Aggression Among Adults in Residential Treatment for Opioid Use Disorder: Preliminary Findings From an Applied Setting

Individuals with opioid use disorder (OUD) evidenced high levels of aggression both before and after the onset of opioid misuse. Continued aggression after abstinence suggested that abstinence alone may be inadequate. The present study investigated dispositional mindfulness in relation to aggressive attitudes, and verbal and physical aggression, by reviewing medical records of 163 adults in residential treatment for OUD. Results of hierarchical regression analyses, controlling for age and alcohol/drug use and problems, revealed a negative relationship between dispositional mindfulness and both aggressive attitudes and verbal aggression. Although dispositional mindfulness negatively related to physical aggression at the bivariate level, only alcohol use and problems related to physical aggression in regression analyses. Mindfulness-based treatments may be a useful avenue for targeting aggression within this population.

Hyperexcitability of VTA dopaminergic neurons in male offspring exposed to physical or psychological prenatal stress

Prenatal stress (PS) exposure leads to cognitive and behavioral alterations in offspring including an increased risk of substance abuse and anxiety disorders. Signalling from dopamine (DA) neurons of the ventral tegmental area (VTA) in the mesoaccumbal and mesocortical pathways plays a vital role in drug dependency and anxiety behavior. To provide further knowledge about the changes in drug seeking behavior and anxiety behaviors in prenatally stressed mice, we conducted ex vivo investigations in VTA brain slices of adult male PS offspring to evaluate the effects of two types of PS (physical vs. psychological) on activity of DA neurons. Elevated plus maze (EPM) was used to assess anxiety-like behaviors and conditioned place preference (CPP) was used to evaluate drug reinforcing effects in mice. An increased anxiety-like behavior and preference to morphine was observed in prenatally stressed mice. PS VTA DA cells exhibited greater I_h current and a higher frequency and amplitude of sEPSCs, which were consistent with a greater degree of pre- or postsynaptic excitability of the VTA. This was confirmed by lower rheobase and lower firing thresholds in PS VTA neurons, as well as increases in spontaneous firing frequency. When taken together, these data suggest that alterations in VTA DA neurons in this mouse model of prenatal stress might be associated with later life alterations in drug seeking and anxiety-like behaviors through their role in mesocortical and mesoaccumbal pathways.

Long-lasting pseudo-social aggressive behavior in opiate-withdrawn mice

Poor sociability and aggressive behavior are major clinical features of opiate use disorders that may contribute to the establishment and maintenance of these harmful diseases. The present study investigated the long-term effects of chronic morphine administration and withdrawal upon social and aggressive behavior as well as the interrelationship between these two behaviors. Thus, social behavior was measured in C57BL/6J male mice 7, 21, 35 and 49 days after cessation of escalating morphine doses (20-100 mg/kg, i.p.) administered during 6 consecutive days, using the three-chamber task for sociability (i.e., preference for an unfamiliar conspecific vs. an object) and social novelty preference (i.e., preference for a novel vs. a familiar conspecific). Moreover, aggressive biting behavior towards an unfamiliar conspecific was assessed throughout the three-chamber tests. Opiate withdrawal increased both social approach and aggressive biting behavior. Moreover, in morphine-withdrawn, but not in control, mice social approach and aggressive behavior followed a similar time-course and positively correlated one with each other, suggesting that social interest was mainly driven by aggressiveness. Aggressive biting behavior was still elevated 49 days after the last morphine administration, revealing that opiate withdrawal is followed by long-lasting aggressiveness. Throughout, opiate withdrawal did not affect social novelty preference, ruling out a role for olfactory or social discrimination dysfunction in the elevated social approach and aggressive behavior. The present findings of very long-lasting aggressive behavior and aggression-driven social approach in opiate-withdrawn mice might help understanding the behavioral and brain underpinnings of poor sociability and aggressiveness commonly observed in opiate use disorders patients.

Intranasal administration of oxytocin decreases task-related aggressive responses in healthy young males

Aggression and distrust are often challenging problems in mental health treatment. Converging evidence reveals that oxytocin increases trust in social interactions and decreases fear of social betrayal. However, oxytocin has also been associated with protective behavior and, as such, might increase defensive aggressive reactions. In this randomized double-blind, placebo-controlled study, the effects of intranasal oxytocin (32IU) on task-related aggressive responses were measured using the Point Subtraction Aggression Paradigm (PSAP). Fifty-seven healthy males were enrolled and randomized to oxytocin (N = 30) or placebo (n = 27). Salivary oxytocin, cortisol and testosterone were measured serially prior to the intervention, and then before and after the PSAP, to evaluate the effects of oxytocin administration on hormonal functioning in relation to aggression. In addition, oxytocin was measured in urine collected directly after the experimental task, reflecting the 2 h period after oxytocin or placebo administration. The proportion of aggressive responses to the PSAP was significantly lower in participants receiving oxytocin versus placebo (β= -0.46, P = 0.01). No significant effect of oxytocin was found regarding defensive reactions. Urinary oxytocin was negatively associated with the proportion of aggressive responses to the PSAP in both the oxytocin and the placebo group (β= -0.02, P < 0.01), suggesting that higher levels of urinary oxytocin corresponded with reduced aggressive responding. Our results indicate that oxytocin administration reduces aggressive behavior in healthy young men. Moreover, increased endogenous urinary oxytocin is associated with less aggressive responding. Taken together, these findings suggest that oxytocin signaling has a causal influence on aggressive behavior.

The Role of the Lateral Hypothalamus in Violent Intraspecific Aggression-The Glucocorticoid Deficit Hypothesis

This review argues for a central role of the lateral hypothalamus in those deviant forms of aggression, which result from chronic glucocorticoid deficiency. Currently, this nucleus is considered a key region of the mechanisms that control predatory aggression. However, recent findings demonstrate that it is strongly activated by aggression in subjects with a chronically downregulated hypothalamus-pituitary-adrenocortical (HPA) axis; moreover, this activation is causally involved in the emergence of violent aggression. The review has two parts. In the first part, we review human findings demonstrating that under certain conditions, strong stressors downregulate the HPA-axis on the long run, and that the resulting glucocorticoid deficiency is associated with violent aggression including aggressive delinquency and aggression-related psychopathologies. The second part addresses neural mechanisms in animals. We show that the experimental downregulation of HPA-axis function elicits violent aggression in rodents, and the activation of the brain circuitry that originally subserves predatory aggression accompanies this change. The lateral hypothalamus is not only an integral part of this circuitry, but can elicit deviant and violent forms of aggression. Finally, we formulate a hypothesis on the pathway that connects unfavorable social conditions to violent aggression via the neural circuitry that includes the lateral hypothalamus.

Distinct pathological profiles of inmates showcasing cluster B personality traits, mental disorders and substance use regarding violent behaviors

High rates of violence are found amid offenders with severe mental illnesses (SMI), substance use disorders (SUDs) and Cluster B personality disorders. Elevated rates of comorbidity lead to inconsistencies when it comes to this relationship. Furthermore, overlapping Cluster B personality traits have been associated with violence. Using multiple correspondence analysis and cluster analysis, this study was designed to differentiate profiles of 728 male inmates from penitentiary and psychiatric settings marked by personality traits, SMI and SUDs following different violent patterns. Six significantly differing clusters emerged. Cluster 1, "Sensation seekers", presented recklessness with SUDs and low prevalence's of SMI and auto-aggression. Two clusters committed more sexual offenses. While Cluster 2, "Opportunistic-sexual offenders", had more antisocial lifestyles and SUDs, Cluster 6, "Emotional-sexual offenders", displayed more emotional disturbances with SMI and violence. Clusters 3 and 4, representing "Life-course-persistent offenders", shared early signs of persistent antisocial conduct and severe violence. Cluster 3, "Early-onset violent delinquents", emerged as more severely antisocial with SUDs. Cluster 4, "Early-onset unstable-mentally ill delinquents", were more emotionally driven, with SMI and auto-aggression. Cluster 5, "Late-start offenders", was less severely violent, and emotionally driven with antisocial behavior beginning later. This study suggests the presence of specific psychopathological organizations in violent inmates.

Psychological stress has a higher rate of developing addictive behaviors compared to physical stress in rat offspring

Prenatal stress could have great influence on development of offspring and might alter cognitive function and other physiological processes of children. The current study was conducted to study the effect of physical or psychological prenatal stress on addictive and anxiety-like behavior of male and female offspring during their adolescence period (postnatal day (PND) 40). Adult female rats were exposed to physical (swimming) or psychological (observing another female rat swimming) stress from day six of gestation for 10 days. Male and female offspring were assayed for anxiety-like behavior, motor and balance function and morphine conditioned place preference using the open field, elevated plus maze (EPM), rotarod and wire grip assay and conditioned place preference. Offspring in both physical and psychological prenatal stress groups demonstrated significant increase in anxiety-like behavior in EPM paradigm, but no alterations were observed in motor and balance function of animals. Offspring in the psychological prenatal stress group had an increased preference for morphine in comparison to control and physical prenatal stress groups. Results of the current study demonstrated that animals exposed to psychological stress during fetal development are at a higher risk of developing addictive behaviors. Further research might elucidate the exact mechanisms involved to provide better preventive and therapeutic interventions.

The Point Subtraction Aggression Paradigm as a laboratory tool for investigating the neuroendocrinology of aggression and competition

A contribution to a special issue on Hormones and Human Competition.The ease of measuring steroids in saliva has led to an increase in investigating their role in competition and aggression in laboratory settings and using behavioral measures of aggression. We review here the Point-Subtraction-Aggression-Paradigm (PSAP) as a measure of costly aggression and we compare and contrast the PSAP to other aggression measures. We describe our use of the PSAP, highlighting how it can be modified to investigate a broad array of experimental questions. We review studies that have investigated neuroendocrine function and the PSAP, and we conclude that across studies the relationship between fluctuations in testosterone and PSAP aggression scores are directionally positive, and are likely specific to men. Investigations of other neuroendocrine measures and the PSAP are fewer, limiting conclusions that can be drawn for other hormones. We provide two versions of the PSAP that can be used with E-PRIME® software for researchers interested in this measure for their laboratories.

Elevated Hair Cortisol Levels among Heroin Addicts on Current Methadone Maintenance Compared to Controls

Whether methadone maintenance treatment (MMT) can improve the basal function of the hypothalamic–pituitary–adrenal (HPA) axis, which is suppressed by long-term heroin consumption, is a matter of debate. The stress state and depression and anxiety symptoms may affect the basal activity of the HPA axis in MMT patients. However, the effect of psychological factors on HPA activity was not simultaneously controlled in previous studies. This study investigated differences in HPA basal activity between MMT patients and controls using psychological variables as covariates. The participants included 52 MMT patients and 41 age-matched, non-heroin-dependent controls. Psychological states were self-reported with the Perceived Stress Scale, Self-Rating Depression Scale and Self-Rating Anxiety Scale. The hair cortisol level was adopted as a biomarker of HPA basal activity and was determined with liquid chromatography tandem mass spectrometry. The results revealed that MMT patients had significantly higher hair cortisol levels than the controls (p<0.05), but the difference was not significant (p>0.05) when the perceived stress, depression and anxiety scores were used as covariates. We concluded that patients with long-term MMT showed higher basal activity of the HPA axis. The high chronic stress state and increase in depression and anxiety symptoms may mask the suppression effect of methadone on the HPA activity.

Comorbid substance use diagnoses and partner violence among offenders receiving pharmacotherapy for opioid dependence

While previous studies find mixed evidence of an association between opioid use and intimate partner violence perpetration among community samples, initial evidence has detected increased rates of partner violence among individuals receiving pharmacological intervention for opioid dependence. The current study evaluated the role of current comorbid substance use diagnoses, a robust risk factor for violent behavior, on the likelihood of perpetrating partner violence among a high risk sample of offenders receiving pharmacological intervention for opioid dependence. The authors analyzed self-report data provided by 81 (55 male) opioid dependent offenders during a court-ordered substance use interview. Approximately one-third of the sample evidenced the recent use of intimate partner violence. Findings indicated that cocaine and benzodiazepine use were independently associated with an increased likelihood of reporting physical partner violence. Alcohol and cannabis use were not associated with partner violence. The current results offer further support for the ongoing need to conduct routine partner violence screenings among substance involved offenders and highlight the importance of developing individualized treatment plans that address comorbid substance use and partner-violent behaviors among individuals in treatment for opioid dependence.

The glucocorticoid/aggression relationship in animals and humans: an analysis sensitive to behavioral characteristics, glucocorticoid secretion patterns, and neural mechanisms

Glucocorticoids control a wide array of biological processes from glucose homeostasis to neuronal function. The mechanisms mediating their effects are similarly varied and include rapid and transient nongenomic effects on calcium trafficking, various neurotransmitter receptors, and other membrane/cytoplasmic proteins, as well as slowly developing but durable genomic effects that are mediated by a large number of glucocorticoid-sensitive genes that are affected after variable lag-times. Given this complexity, we suggest that the aggression/glucocorticoid relationship cannot be reduced to the simple "stimulation/inhibition" question. Here, we review the effects of glucocorticoids on aggression by taking into account the complexities of glucocorticoid actions. Acute and chronic effects were differentiated because these are mediated by different mechanisms. The effects of chronic increases and decreases in glucocorticoid production were discussed separately, because the activation of mechanisms that are not normally activated and the loss of normal functions should not be confounded. Findings in healthy/normal subjects and those obtained in subjects that show abnormal forms of behavior or psychopathologies were also differentiated, because the effects of glucocorticoids are indirect, and largely depend on the properties of neurons they act upon, which are altered in subjects with psychopathologies. In addition, the conditions of glucocorticoid measurements were also thoroughly evaluated. Although the role of glucocorticoids in aggression is perceived as controversial by many investigators, a detailed analysis that is sensitive to glucocorticoid and behavioral measure as well as to the mediating mechanism suggests that this role is rather clear-cut; moreover, there is a marked similarity between animal and human findings.

The physician's unique role in preventing violence: a neglected opportunity?

BACKGROUND

Episodes of explosive rage and violence comprise a symptom complex which can have a devastating effect on a person's life. In the community this behavior is seen as workplace violence, domestic abuse and road rage, while in the clinical setting, this behavior is rarely mentioned by patients, despite evidence that it can signify an important biological disorder that may afflict more than three percent of the population.

DISCUSSION

Patients are often reluctant to seek help for episodic attacks of rage, especially attacks which are accompanied by physical violence. Although, in the past, clinicians have had few treatment options to offer, recent neuroscience advances have created new possibilities to understand and help patients with this neglected problem. No formal medical guidelines for treating violence exist; however, many patients can be helped by diagnosis, referral and treatment. Treatment can include pharmaceuticals and nutrients, as well as referral for anger management or behavioral therapy.

SUMMARY

The astute clinician has an opportunity to positively impact an important problem through the diagnosis and treatment of patients with symptoms of intermittent explosive disorder.

Drug abuse and intimate partner violence: a comparative study of opioid-dependent fathers

Because very little is known about the coparenting relationships of drug-abusing men, this comparative study was designed to examine the lifetime prevalence and recent frequency of intimate partner violence in the coparenting relationships of 106 fathers enrolled in methadone maintenance treatment. When compared with 118 community controls, the opioid-dependent fathers reported greater prevalence of physical, sexual, and psychological aggression directed at the mother of their youngest biological child over the course of the relationship. They also reported more frequent physical, sexual, and psychological aggression directed at the mother during the previous year. Similarly, the opioid-dependent fathers reported both greater prevalence of physical and sexual aggression directed at them by the mother of their youngest child over the course of the relationship and more frequent sexual aggression directed at them over the previous year. The results highlight the need for clinicians to consider risk for intimate partner violence in coparenting relationships when planning family-oriented intervention designed to meet the needs of fathers, mothers, and children affected by chronic drug abuse.

The relationship between basal and acute HPA axis activity and aggressive behavior in adults

The hypothalamic-pituitary-adrenal (HPA) axis seems to play a major role in the development, elicitation, and enhancement of aggressive behavior in animals. Increasing evidence suggests that this is also true for humans. However, most human research on the role of the HPA axis in aggression has been focusing on highly aggressive children and adolescent clinical samples. Here, we report on a study of the role of basal and acute HPA axis activity in a sample of 20 healthy male and female adults. We used the Taylor Aggression Paradigm to induce and measure aggression. We assessed the cortisol awakening response as a trait measure of basal HPA axis activity. Salivary free cortisol measures for the cortisol awakening response were obtained on three consecutive weekdays immediately following awakening and 30, 45, and 60 min after. Half of the subjects were provoked with the Taylor Aggression Paradigm to behave aggressively; the other half was not provoked. Acute HPA axis activity was measured four times, once before and three times after the induction of aggression. Basal cortisol levels were significantly and negatively related to aggressive behavior in the provoked group and explained 67% of the behavioral variance. Cortisol levels following the induction of aggression were significantly higher in the provoked group when baseline levels were taken into account. The data implicate that the HPA axis is not only relevant to the expression of aggressive behavior in clinical groups, but also to a large extent in healthy ones.

An experimental study of aggressive and neutral interpretative bias in opiate-dependent and opiate-abstinent men

There is a paucity of research on the relationship between opiate use and aggression, and no previous study has examined this from a cognitive theoretical perspective, which views an individual's interpretation of information as a central mediator of their response to it. This study aimed to determine whether opiate users and ex-users differed from opiate-naïve controls on a task which involved processing ambiguous sentences. In an independent group design, the interpretative bias task was administered to 64 participants: 21 opiate-dependent receiving methadone maintenance treatment, 21 opiate-abstinent in rehabilitation, and 22 healthy unemployed controls. We found that both opiate-dependent and opiate-abstinent groups interpreted ambiguous sentences in a neutral rather than an aggressive way, whereas controls showed no bias in either direction. In the opiate-dependent group, neutral interpretative bias correlated both with their current dose of methadone and years of methadone use. These findings indicate that current and ex-opiate users in treatment have a bias towards neutral interpretations of ambiguous information. The fact that neutral interpretative bias in opiate-dependent individuals correlated with current dose and years of methadone use suggests that methadone treatment is associated with a neutral cognitive bias. Decreased testosterone levels associated with chronic opiate use may underpin this neutral bias.

Testosterone responses to competition predict future aggressive behaviour at a cost to reward in men

The extent to which trait factors (baseline testosterone concentrations, trait dominance) and state factors (change in social status, change in testosterone concentrations) would predict reactive aggression in a subsequent task that involved provocation was examined in 99 participants (39 men and 60 women). Participants first competed in same-sex dyads on a Number Tracing Task for which the outcome (win or loss) was rigged. After the competition, participants performed the Point Subtraction Aggression Paradigm (PSAP), a behavioural measure of reactive aggression against an opponent (actually a computer program). Trait dominance predicted baseline testosterone in men, but not women, and men made more aggressive responses than did women. Baseline testosterone concentrations did not predict aggressive behaviour in either men or women. Winners and losers did not differ in competition-induced change in testosterone. However, change in testosterone concentrations predicted aggressive responses in the PSAP for men in the loss condition, and aggressive responses were made at a cost to obtaining reward points. For men in the win condition, aggressive responses were predicted by an interaction between trait dominance and change in testosterone concentrations. These findings suggest that situational changes in testosterone concentrations modulate future aggressive behaviour in men.

Aggressive behavior and change in salivary testosterone concentrations predict willingness to engage in a competitive task

The current study investigated relationships among aggressive behavior, change in salivary testosterone concentrations, and willingness to engage in a competitive task. Thirty-eight male participants provided saliva samples before and after performing the Point Subtraction Aggression Paradigm (a laboratory measure that provides opportunity for aggressive and defensive behavior while working for reward; all three involve pressing specific response keys). Baseline testosterone concentrations were not associated with aggressive responding. However, aggressive responding (but not point reward or point protection responding) predicted the pre- to post-PSAP change in testosterone: Those with the highest aggressive responding had the largest percent increase in testosterone concentrations. Together, aggressive responding and change in testosterone predicted willingness to compete following the PSAP. Controlling for aggression, men who showed a rise in testosterone were more likely to choose to compete again (p=0.03) and controlling for testosterone change, men who showed the highest level of aggressive responding were more likely to choose the non-competitive task (p=0.02). These results indicate that situation-specific aggressive behavior and testosterone responsiveness are functionally relevant predictors of future social behavior.

Mood and neuroendocrine response to a chemical stressor, metyrapone, in buprenorphine-maintained heroin dependence

BACKGROUND

Heroin dependence is associated with a hyperactive hypothalamic-pituitary-adrenal (HPA) axis, proposed as a biological correlate of craving. Maintenance treatment with methadone normalizes HPA axis activity. Here, we examined HPA axis activity under maintenance treatment with the increasingly utilized partial opiate agonist buprenorphine.

METHODS

Responses to a metyrapone challenge were compared in 20 buprenorphine-maintained heroin addicts and 20 healthy volunteers (10 received a single 50 mg naltrexone dose [NTX+] and 10 received no naltrexone [NTX-]). Patients were 16 male subjects and 4 female subjects, aged 30 to 38 years, heroin-dependent and relapse-free under buprenorphine maintenance (BUP) for a minimum of 6 months. Healthy volunteers were 9 male subjects and 11 female subjects, aged 36 to 49 years, with no history of dependence. Serial measures were obtained of plasma adrenocorticotropic hormone (ACTH) and cortisol and Profile of Mood States (POMS) ratings over time. Subjects were genotyped for the OPRM1 118A/G polymorphism.

RESULTS

Buprenorphine maintenance showed a dampened HPA axis response to metyrapone, with OPRM1 118G carriers showing a significantly attenuated response compared with 118A carriers. The response of the NTX+ group was markedly increased. In contrast, negative affect was elevated in the BUP group but did not differ between NTX- and NTX+. Buprenorphine maintenance and NTX- groups did not differ in positive affect, whereas the NTX+ group was lower.

CONCLUSIONS

In contrast to exaggerated HPA axis responsiveness reported in untreated heroin dependence, response to metyrapone was subnormal in heroin addicts maintained on buprenorphine. Despite this, increased measures of negative affect were seen in this group. This implies a dissociation of HPA axis responsiveness and affect in heroin dependence.

Relationship of personality traits and drug of choice by cocaine addicts and heroin addicts

The link between specific personality profiles and a single psychotropic drug of choice is still unclear and only partially explored. The present study compares three groups of male subjects: 85 patients manifesting heroin dependence (age: 30.07 +/- 2.78), 60 patients manifesting cocaine dependence (age: 31.96 +/- 3.1), and 50 healthy subjects from a random population sample (age: 33.25 +/- 1.45). The patients included in the study showed a long-lasting history of dependence on heroin or cocaine, respectively, 5.2 +/- 2.5 years, 4.6 +/- 2.9 years, and were stabilized in treatment, and abstinent, at least 4 weeks at the time of the diagnostic assessment. Heroin addicts (52.90%) were on methadone maintenance treatment. Cocaine addicts (11.60%) were treated with selective serotonin reuptake inhibitors. Personality traits were measured by the Minnesota Multiphasic Personality Inventory (MMPI-2) and Cloninger's Three-dimensional Personality Questionnaire (TPQ). Character and quantification of aggressiveness were measured by the Buss-Durkee Hostility Inventory (BDHI). Heroin-dependent patients (group A) scored significantly higher on hysteria, masculine-feminine and social introversion subscales of the MMPI, and significantly lower on the harm avoidance (HA) subscale of the TPQ than cocaine addicts. In contrast, scores on the MMPI for hypochondria, psychopathic deviance, and paranoia dimensions were more elevated in cocaine addicts than in heroin-dependent patients. Cocaine addicts scored higher than heroin addicts on the "direct" aggressiveness subscale and on the BDHI total score. Cocaine addicts did not differ from healthy controls on harm avoidance (behavioral control). Although cocaine addicts showed more consistent psychopathic deviance and overt aggressiveness than heroin addicts, higher harm avoidance (behavioral control), hypochondria (or worry about their health), and social extroversion may reduce their proneness to overt antisocial behavior and allow relatively higher levels of social integration. The study's limitations are noted.

Human proactive aggression: association with personality disorders and psychopathy

Aggressive behaviors can be divided into two categories: reactive and proactive. Reactive aggressive behaviors occur in response to a stimulus or provocation. Proactive aggressive behaviors occur without provocation and are goal directed. A number of findings have suggested that individuals displaying proactive aggression may be discerned from individuals not displaying proactive aggression on measures of personality, psychopathology and psychopathy as well as in aggressive histories and type and severity of aggressive behaviors committed. In this study, subjects were recruited from a large urban community and classified as proactive (n = 20), reactive-only (n = 20) or nonaggressive (n = 10) based on laboratory behavioral testing. Subjects were administered a battery of questionnaires and structured interviews pertaining to personality disorders and psychopathy. It was hypothesized that proactive aggressive subjects would show greater numbers of personality disorders and have greater psychopathy relative to reactive-only and nonaggressive subjects. These hypotheses were supported. These results suggest that proactive aggression may be identified in a laboratory-based task, and differences between proactive and reactive-only aggressors can be detected.

Experimentally induced aggressiveness in heroin-dependent patients treated with buprenorphine: comparison of patients receiving methadone and healthy subjects

Objective measures of experimentally induced aggressiveness were evaluated in heroin-dependent patients (HDP), 15 receiving buprenorphine (BUP) and 15 receiving methadone (METH) treatment. HDP were randomly assigned to BUP and METH groups. Fifteen healthy subjects (CONT) were included in the study as controls. During a laboratory task, the Point Subtraction Aggression Paradigm, subjects earned monetary reinforcement and could respond by ostensibly subtracting money from a fictitious subject (the aggressive response). Money-earning (points maintained) responses did not differ in BUP patients and in controls. In contrast, point-maintained responses were significantly lower in the group of HDP treated with METH than in both the BUP and CONT groups. Aggressive responses were significantly higher in the HDP group than in the CONT group. No significant differences in aggressive responses were found between the BUP and METH groups. Baseline concentrations of plasma adrenocorticotropic hormone (ACTH) and cortisol (CORT) were higher in HDP than in CONT. During the experimental task, ACTH and CORT increased significantly less in METH patients than in BUP patients and CONT. Norepinephrine (NE) and epinephrine (EPI) levels increased significantly more in HDP than in CONT, without any difference between the METH and BUP patients. PSAP aggressive responses positively correlated with NE and EPI changes, as well as with Buss-Durkee Hostility Inventory (BDHI) scores in both METH and BUP patients and also in CONT subjects. No correlation was found between the extent of heroin exposure, drug doses and aggressiveness levels. BUP, similarly to METH, does not seem to affect outward-directed aggressiveness, as aggressive responses related more to monoamine levels and personality traits than to the action of opioid agonists. Money-earning responses seemed to be unimpaired in BUP patients.

Is the bipolar spectrum the psychopathological substrate of suicidality in heroin addicts?

BACKGROUND

To describe the prevalence and the risk factors of suicidal ideation in a cohort of Italian opioid addicts presenting for treatment.

METHOD

Systematic cross-sectional clinical data on suicidal ideation, socio-demographic variables, psychiatric status, social adjustment, status and history of addiction in 616 patients were gathered.

RESULTS

Suicidal thoughts during the past week were reported by 29.1%. Suicidal thoughts were more frequent in patients with bipolar spectrum diagnoses (OR = 1.42) and in patients with depressive and aggressive symptoms (multiple R = 0.47). The odds of having suicidal thoughts were also higher for subjects receiving public welfare benefits (OR = 1.69), unemployed patients (OR = 1.37), those with early onset of heroin dependence (OR = 1.36), living alone (OR = 1.33), and experiencing problems in organizing social contacts and leisure time (OR = 1.28).

CONCLUSION

Current suicidal ideation was a common feature of patients with opioid addiction. Depression and hostility as part of the bipolar spectrum - in the context of early-onset drug dependence, work and social/leisure problems - appear independently associated with suicidal ideation. Given the elevated rates of completed suicide in heroin addiction, these data have implications for preventing suicide in patients with this type of addiction. Prospective data are needed to further address this important clinical and public health agenda.

Impulsivity as a common process across borderline personality and substance use disorders

Borderline personality disorder (BPD) is a significant public health problem characterized by persistent problems with emotional, behavioral, cognitive, and interpersonal functioning. Research indicates an especially high rate of comorbidity between BPD and Substance Use Disorders (SUD). In trying to better understand, and therefore improve the assessment, prevention, and treatment of these disorders, researchers have considered the role of impulsivity. Indeed, impulsivity consistently has been shown to be a biologically-based, heritable characteristic with emergent psychological properties linked to the development and maintenance of BPD and SUD. Following from a previous review of the comorbidity between BPD and SUD (Trull, T. J., Sher, K. J., Minks-Brown, C., Durbin, J., & Burr, R. (2000). Borderline personality disorder and substance use disorders: A review and integration. Clinical Psychology Review, 20, 235-253), the current manuscript revisits the role of impulsivity as a common process across these disorders with a specific focus on the multidimensional nature of impulsivity and its interaction with trait and state negative affectivity.

Psychophysiology of aggression, psychopathy, and conduct problems: a meta-analysis

A meta-analysis of 95 studies was conducted to investigate the relations of heart rate (HR) and electrodermal activity (EDA) with aggression, psychopathy, and conduct problems. Analyses revealed a complex constellation of interactive effects, with a failure in some cases of autonomic patterns to generalize across antisocial spectrum behavior constructs. Low resting EDA and low task EDA were associated with psychopathy/sociopathy and conduct problems. However, EDA reactivity was positively associated with aggression and negatively associated with psychopathy/sociopathy. Low resting HR and high HR reactivity were associated with aggression and conduct problems. Physiology--behavior relations varied with age and stimulus valence in several cases. Empirical and clinical implications are discussed.

Simultaneous liquid chromatographic analysis of catecholamines and 4-hydroxy-3-methoxyphenylethylene glycol in human plasma

The comparison of two HPLC methods, one with electrochemical detection and the other with coulometric detection, for the simultaneous analysis of catecholamines and 4-hydroxy-3-methoxyphenylethylene glycol (MHPG) in human plasma is presented. The careful pre-treatment of plasma samples is based on an innovative two-step procedure by means of solid-phase extraction (SPE) which uses one single hydrophilic-lipophilic balance cartridge. The extraction yield values found were higher than 85% for epinephrine, norepinephrine and MHPG, and higher than 70% for dopamine. The assays carried out on real plasma samples with the coulometric system gave good results in terms of sensitivity (limits of quantitation: 0.10-0.15 ng ml(-1) for catecholamines, 0.6 ng ml(-1) for MHPG) and selectivity, while interference was sometimes found when using the amperometric system. Precision was also satisfactory, with relative standard deviation values for intermediate precision always lower than 6%. The HPLC method with coulometric detection coupled to a novel SPE procedure is thus suitable for the simultaneous determination of catecholamines and MHPG in plasma of volunteers subjected to experimental stress.

Aggressive responding in abstinent heroin addicts: neuroendocrine and personality correlates

Objective measures of experimentally induced aggressiveness were evaluated in 20 abstinent heroin-dependent subjects, in comparison with 20 normal healthy male subjects. All the subjects were preliminarily submitted to DSM-IV interviews, Buss-Durkee Hostility Inventory (BDHI) and Minnesota Multiphasic Personality Inventory (MMPI II). During a laboratory task, the Point Subtraction Aggression Paradigm (PSAP), subjects earned monetary reinforcers with repeated button presses and were provoked by the subtraction of money, which was attributed to a fictitious other participant. Subjects could respond by ostensibly subtracting money from the fictitious subject (the aggressive response). Money-earning responses were not different in drug-free heroin addicts and controls during the first two sessions and significantly lower during the third session in heroin-dependent subjects (t=2.99, P<.01). Aggressive responses were significantly higher (F=4.9, P<.01) in heroin addicted individuals, in comparison with controls. During the experimentally induced aggressiveness, plasma adrenocorticotropic hormone (ACTH) and cortisol (CORT) concentrations increased less significantly, and norepinephrine (NE) and epinephrine (EPI) levels, together with heart rate (HR), increased more significantly in abstinent heroin-dependent subjects than in healthy subjects. PSAP aggressive responses positively correlated with catecholamine changes, BDHI "direct" and "irritability" scores, MMPI "psychopathic deviate" scores in heroin-dependent subjects and controls, and with CORT responses only in healthy subjects. No correlation was found between heroin-exposure extent (substance abuse history duration) and aggressiveness levels. The present findings suggest that heroin-dependent patients have higher outward-directed aggressiveness than healthy subjects, in relation with monoamine hyperreactivity, after long-term opiate discontinuation. Aggressiveness in heroin addicts seems to be related more to the personality traits than to drug effects. The impairment of hypothalamus-pituitary-adrenal (HPA) axis in abstinent addicted individuals could be due to a long-lasting action exerted by opiates on proopiomelanocortin (POMC) or to a premorbid psychobiological condition, in association with increased sympathetic arousal.

Intermittent morphine administration induces dependence and is a chronic stressor in rats

Although constant treatment with morphine (implanted pellets) does not activate the hypothalamic-pituitary-adrenal (HPA) axis, intermittent injections of morphine may constitute a chronic stressor in rats. To test this hypothesis, we compared the effects of morphine in escalating doses (10-40 mg/kg, s.c.) or saline injected twice daily for 4 days on energy balance, hormones, HPA responses to novel restraint and central corticotropin-releasing factor (CRF) mRNA 12 h and 8 days after the last morphine injection in adult male Sprague-Dawley rats. Weight gain stopped at the onset of morphine, weight loss was marked 36 h postmorphine; thereafter, body weight gain paralleled saline controls. At 12 h, insulin, leptin, and testosterone concentrations were reduced but normalized by 8 days. Restraint and tail nicks caused facilitated ACTH responses at 12 h, under-responsiveness at 8 days. CRF mRNA, measured only at 12 h, was increased in the paraventricular (PVN) and Barrington's nuclei (BAR), decreased in the bed nuclei of the stria terminalis (BNST) and unchanged in the amygdala (CeA) in morphine-treated rats. After stress, CRF mRNA increased in PVN in both groups, increased in BAR and decreased in BNST in saline but not morphine groups, and was unchanged in CeA in both groups. Results from all variables characterize intermittent morphine injections as a chronic stressor. In contrast to constant treatment, injected morphine probably allows some withdrawal during each 12 h interval, causing repeated stress. Drug addicts treat themselves intermittently, and stress causes relapse after withdrawal. Thus, intermittent morphine, itself, may promote relapse.

Neuroendocrine responses to experimentally-induced emotions among abstinent opioid-dependent subjects

The present study investigated neuroendocrine and cardiovascular changes during experimentally-induced affective states in abstinent heroin-dependent subjects and healthy controls. The procedure for eliciting emotions in all subjects used pleasant and unpleasant stimuli that did not differ in subjective arousal properties. We investigated whether the valence of the stimuli differentially affected neuroendocrine responses by comparing neutral, pleasant and unpleasant pictures on heart rate (HR), systolic (SBP) and diastolic blood pressure (DBP), methyl-OH-phenyl-glycol (MHPG), norepinephrine (NE), epinephrine (EPI), adrenocorticotrophic hormone (ACTH) and cortisol (CORT) plasma levels. Twelve abstinent heroin-dependent subjects, in comparison with 12 control subjects, were submitted to three experimental sessions, each on one of three experimental days a week apart, in counterbalanced order: day 1=unpleasant pictures, day 2=pleasant pictures, day 3=neutral pictures. In the rating of subjective arousal pleasant and unpleasant stimuli received the same high score in comparison with neutral stimuli; a different cardiovascular and neuroendocrine pattern was obtained in healthy subjects: unpleasant stimuli elicited increases in HR, SBP, MHPG, NE, ACTH, CORT, whereas neutral and pleasant stimuli did not induce any significant response in hormonal levels. In contrast, in heroin addicts, despite increased perceptions of unpleasantness, HR, SBP, MHPG and NE levels did not increase after disliked stimuli; these subjects also reported increased arousal during exposure to neutral stimuli. In comparison with controls, addicted individuals showed higher CORT and ACTH basal levels, and a consequent lack of response to unpleasant stimuli. The results indicate that neuroendocrine and cardiovascular systems respond selectively to affective, motivationally relevant stimuli, and that substance use disorders may be associated with dysregulation of emotion-processing mechanisms.

Experimentally induced aggressive behavior in subjects with 3,4-methylenedioxy-methamphetamine ("Ecstasy") use history: psychobiological correlates

PURPOSE

Objective measures of experimentally induced aggressiveness were evaluated in 12 male 3,4-methylenedioxy-methamphetamine (MDMA, "Ecstasy") users, in comparison with 20 healthy male subjects.

METHODS

All the subjects were preliminarily submitted to DSM-IV interviews and Buss-Durkee Hostility Inventory (BDHI). During a laboratory task, the Point Subtraction Aggression Paradigm (PSAP), subjects earned monetary reinforcers with repeated button presses, and were provoked by the subtraction of money that was attributed to a fictitious other participant. Subjects could respond by ostensibly subtracting money from the fictitious subject (the aggressive response). Escape responses were also possible protecting the counter from monetary subtractions.

RESULTS

Money-earning responses were not different in Ecstasy users and controls; aggressive responses were significantly higher in Ecstasy users in comparison with control subjects (F=20.74, P<.001). Baseline adrenocorticotropic hormone (ACTH) and cortisol (CORT) levels were higher in Ecstasy users than in controls. No difference was found in norepinephrine (NE) and epinephrine (EPI) basal levels of the two groups. During the experimentally induced aggressiveness, plasma ACTH concentrations increased significantly less and NE and EPI levels, together with heart rate (HR), increased significantly more in Ecstasy users than in healthy subjects. Despite ACTH-blunted responses, CORT did not increase differently from controls in Ecstasy users. PSAP aggressive responses positively correlated with catecholamines and CORT changes, BDHI Direct Aggression and Irritability scores, both in Ecstasy users and controls. A significant correlation was found between Ecstasy exposure extent and aggressive responses (r=.78, P<.001).

IMPLICATIONS

Our findings suggest that Ecstasy users have higher outward-directed aggressiveness than healthy subjects. Aggressiveness in MDMA subjects seems to be associated more with MDMA pharmacological effects than with personality traits: Nevertheless, a premorbid psychobiological proneness to aggressive behavior cannot be excluded. Increased catecholamines reactivity, basal hypothalamus-pituitary-adrenal (HPA) axis hyperactivity, and blunted ACTH responses could be due to MDMA action on monoaminergic pathways and adrenal function.