Impulsivity and risk for prescription opioid misuse in a chronic pain patient sample

Exploring Social Impairment in Those with Opioid Use Disorder: Linking Impulsivity, Childhood Trauma, and the Prefrontal Cortex

Background

Challenges with social functioning, which is a hallmark of opioid use disorder (OUD), are a drawback in treatment adherence and maintenance. Yet, little research has explored the underlying mechanisms of this impairment. Impulsivity, a known risk factor for OUD, and corresponding neural alterations may be at the center of this issue. Childhood adversity, which has been linked to both impulsivity and poorer treatment outcomes, could also affect this relationship. This study aims to understand the relationship between impulsivity and social functioning in those recovering from OUD. Differences in the prefrontal cortex will be analyzed, as well as potential moderating effects of childhood trauma.

Methods

Participants with (N = 16) and without (N = 19) social impairment completed a survey (e.g., social functioning, Barrat's Impulsivity Scale, Adverse Childhood Experiences (ACEs) and cognitive tasks while undergoing neuroimaging. Functional near infrared spectroscopy (fNIRS), a modern, portable, wearable and low-cost neuroimaging technology, was used to measure prefrontal cortex activity during a behavioral inhibition task (Go/No-Go task).

Results

Those who social functioning survey scores indicated social impairment (n = 16) scored significantly higher on impulsivity scale (t(33)= -3.4, p < 0.01) and reported more depressive symptoms (t(33) = -2.8, p < 0.01) than those reporting no social impairment (n = 19). Social functioning was negatively correlated with impulsivity (r=-0.7, p < 0.001), such that increased impulsivity corresponded to decreased social functioning. Childhood trauma emerged as a moderator of this relationship, but only when controlling for the effects of depression, B=-0.11, p = 0.023. Although both groups had comparable Go/No-Go task performance, the socially impaired group displayed greater activation in the dorsolateral (F(1,100.8) = 7.89, p < 0.01), ventrolateral (F(1,88.8) = 7.33, p < 0.01), and ventromedial (F(1,95.6) = 7.56, p < 0.01) prefrontal cortex during impulse control.

Conclusion

In addition to being more impulsive, individuals with social impairment exhibited differential activation in the prefrontal cortex when controlling responses. Furthermore, the impact of impulsivity on social functioning varies depending on ACEs demonstrating that it must be considered in treatment approaches. These findings have implications for addressing social needs and impulsivity of those in recovery, highlighting the importance of a more personalized, integrative, and trauma-informed approach to intervention.

Emotion Regulation and Psychological Dependence on Pain Medication among Hospital Outpatients with Chronic Spinal Pain: The Influence of Rumination about Pain and Alexithymia

Objective: To examine the extent to which pain acceptance, pain catastrophising and alexithymia moderate associations between pain intensity and psychological pain medication dependence. Methods: Participants (106 hospital outpatients with chronic spinal pain) completed the Leeds Dependence Questionnaire (LDQ) to measure psychological dependence on pain medication, and the Chronic Pain Acceptance Questionnaire-8 (CPAQ-8), the Pain Catastrophising Scale (PCS) and the Toronto Alexithymia Scale-20 (TAS-20), plus the Depression, Anxiety and Stress Scale-21 (DASS-21). Results: Multiple linear regression showed that degree of psychological dependence (measured dimensionally across the range of LDQ scores) was associated with TAS subscale difficulty identifying feelings (DIF) (β = 0.249, p = <0.002) and PCS subscale rumination (β = 0.193, p = 0.030), independently of pain intensity and risk behaviors for medication misuse. The effect of pain intensity was moderated by rumination, with pain intensity more strongly associated with dependence when rumination was high (interaction β = 0.192, p = 0.004). Logistic regression showed that the effect of pain intensity on severe dependence (measured categorically as LDQ score ≥ 20) was moderated by alexithymia, so that severe dependence was independently associated with the combination of intense pain and high alexithymia (interaction odds ratio = 7.26, 95% CIs = 1.63-32.42, p = 0.009). Conclusions: Rumination and alexithymia moderated the associations between pain intensity and psychological pain medication dependence, consistent with emotion regulation theory. This raises the possibility that specifically targeting rumination about pain and symptoms of alexithymia could potentially improve the effectiveness of psychological interventions for chronic pain and help people to avoid or reduce their psychological dependence on pain medication.

Psychological profiles and prescription opioid misuse, craving, and withdrawal in people with chronic pain

BACKGROUND

The negative consequences of prescription opioid misuse and opioid use disorder make it relevant to identify factors associated with this problem in individuals with chronic pain. This cross-sectional study aimed at identifying subgroups of people with chronic pain based on their psychological profiles, prescription opioid misuse, craving, and withdrawal.

METHODS

The sample comprised 185 individuals with chronic pain. We performed hierarchical cluster analysis on impulsivity, anxiety sensitivity, pain acceptance, pain intensity, opioid misuse, craving, and withdrawal.

RESULTS

The four-cluster solution was the optimal one. Misuse, craving, and anxiety sensitivity were higher among people in the Severe-problems cluster than among people in the other three clusters. Withdrawal was the highest in the High-withdrawal cluster. Impulsivity was higher among people in the Severe-problems and High-withdrawal clusters than those in the Moderate-problems and Mild-problems clusters. Pain acceptance was higher among people in the Mild-problems cluster than among people in the other three clusters. Anxiety sensitivity and misuse were higher among people in the Moderate-problems cluster than among people in the Mild-problems cluster.

CONCLUSIONS

These results support that impulsivity, anxiety sensitivity, and pain acceptance are useful constructs to identify subgroups of people with chronic pain according to their level of prescription opioid misuse, craving, and withdrawal. The results of this study may help in selecting the early intervention most suitable for each of the identified profiles.

SIGNIFICANCE

The psychological profile of individuals with chronic pain, prescription opioid misuse, craving, and withdrawal is characterized by fearing anxiety-related symptoms due to the catastrophic interpretation of such symptoms and reacting impulsively to negative moods. In contrast, participants with high pain acceptance had less prescription opioid misuse, craving, and withdrawal. The profiles identified in this study could help clinicians select targets for intervention among profiles with similar needs and facilitate early interventions to prevent opioid misuse onset or aggravation.

Impulsivity Dimensions Predict Treatment Dropout Among Women in Residential Treatment for Substance Use Disorders

Residential treatment for substance use disorders (SUDs) is effective at reducing substance use, dependence, and other related problems. However, dropout from treatment against medical advice (AMA) is common in residential treatment settings. Studies have shown that impulsivity is associated with substance misuse and treatment dropout in predominately male samples, but less is known regarding whether impulsivity dimensions predict treatment dropout among women. This study examined impulsivity dimensions (ie, negative urgency, positive urgency, lack of perseverance, lack of premeditation, and sensation seeking) as predictors of dropout AMA among women in a residential substance use treatment facility (N = 229). Logistic regression results demonstrated that elevations in lack of perseverance and sensation seeking were associated with an increased odds of treatment dropout AMA and that lack of premeditation was associated with a decreased odds of treatment dropout AMA. Study findings suggest that early evidence-based interventions for sensation seeking and lack of perseverance may improve retention of women in residential treatment.

Mu Opioid Receptor-Positive Neurons in the Dorsal Raphe Nucleus Are Impaired by Morphine Abstinence

BACKGROUND

Chronic opioid exposure leads to hedonic deficits and enhanced vulnerability to addiction, which are observed and even strengthen after a period of abstinence, but the underlying circuit mechanisms are poorly understood. In this study, using both molecular and behavioral approaches, we tested the hypothesis that neurons expressing mu opioid receptors (MORs) in the dorsal raphe nucleus (DRN) are involved in addiction vulnerability associated with morphine abstinence.

METHODS

MOR-Cre mice were exposed to chronic morphine and then went through spontaneous withdrawal for 4 weeks, a well-established mouse model of morphine abstinence. We studied DRN-MOR neurons of abstinent mice using 1) viral translating ribosome affinity for transcriptome profiling, 2) fiber photometry to measure neuronal activity, and 3) an opto-intracranial self-stimulation paradigm applied to DRN-MOR neurons to assess responses related to addiction vulnerability including persistence to respond, motivation to obtain the stimulation, self-stimulation despite punishment, and cue-induced reinstatement.

RESULTS

DRN-MOR neurons of abstinent animals showed a downregulation of genes involved in ion conductance and MOR-mediated signaling, as well as altered responding to acute morphine. Opto-intracranial self-stimulation data showed that abstinent animals executed more impulsive-like and persistent responses during acquisition and scored higher on addiction-like criteria.

CONCLUSIONS

Our data suggest that protracted abstinence to chronic morphine leads to reduced MOR function in DRN-MOR neurons and abnormal self-stimulation of these neurons. We propose that DRN-MOR neurons have partially lost their reward-facilitating properties, which in turn may lead to increased propensity to perform addiction-related behaviors.

Reward drive moderates the effect of depression-related cognitive mechanisms on risk of prescription opioid misuse among patients with chronic non-cancer pain

Depression, a prognostic factor for prescription opioid misuse commonly occurs in people with chronic non-cancer pain (CNCP). However, the mechanisms linking depression and prescription opioid misuse remain unclear. This study examined the potential mediating role of pain catastrophizing in the association between depressive symptoms and prescription opioid misuse risk, and impulsivity traits as possible moderators of these relationships. Individuals (N = 198; 77% women) with CNCP using prescription opioids participated in a cross-sectional online survey with validated measures of depression, pain catastrophizing, rash impulsiveness, reward drive, anxiety, pain severity and prescription opioid misuse. Meditation analyses with percentile-based bootstrapping examined pathways to prescription opioid use, controlling for age, sex, pain severity, and anxiety symptoms. Partial moderated mediation of the indirect effect of depressive symptoms on prescription opioid misuse risk through pain catastrophizing by rash impulsiveness and reward drive were estimated. Pain catastrophizing mediated depressive symptoms and prescription opioid misuse risk. Indirect effects were stronger when moderate to high levels of reward drive were included in the model. Findings suggest the risk of prescription opioid misuse in those experiencing depressive symptoms and pain catastrophizing is particularly higher for those higher in reward drive. Treatments targeting these mechanisms may reduce opioid misuse risk. PERSPECTIVE: This article identifies reward drive as a potentially important factor increasing the effects of depression-related cognitive mechanisms on risk of prescription opioid misuse in those with CNCP. These findings could assist in personalizing clinical CNCP management to reduce the risks associated with opioid misuse.

Differential Experience of Interdose Withdrawal During Long-Term Opioid Therapy and its Association With Patient and Treatment Characteristics: A Latent Class Analysis in Chronic Pain Population

Opioid withdrawal is characterized by a set of physical and psychological symptoms that depend on both opioid and patient specific characteristics. The present study aims to identify different latent classes of chronic pain patients according to the type of opioid withdrawal symptoms experienced, and to analyze the relationships between the classes and demographic, opioid therapy, psychological and substance use variables. This cross-sectional descriptive study included 391 chronic pain patients on long-term opioid therapy. A Latent Class Analysis (LCA) identified 3 classes (BIC = 7051.89, entropy = .87, LRTs P < .01). The mild withdrawal class showed low probabilities of presenting physical and psychological symptoms, the moderate withdrawal class was characterized by experiencing psychological symptoms, and the severe withdrawal class stood out for high probabilities of presenting both types of symptoms. The classes differed from each other, with higher rates of moderate-severe POUD, opioid misuse, anxiety, depression, and greater pain intensity and interference in more severe withdrawal classes (P < .05). The multinomial logistic regression showed that moderate-severe POUD and anxiety were the strongest variables related to moderate (OR_POUD = 3.34, OR_Anxiety = 2.58) and severe withdrawal classes (OR_POUD = 4.26, OR_Anxiety = 5.15). Considering that POUD and anxiety were strongly related to a more severe withdrawal syndrome, the inclusion of psychological interventions in pain management seems critical in this population. PERSPECTIVE: Although interdose opioid withdrawal is common in chronic pain patients, this study shows 3 different patterns in its experience (mild, moderate, and severe withdrawal). A more severe withdrawal may result in reduced effectiveness of opioids in relieving pain and increased negative consequences, such as higher risk of POUD. Findings that could help improve chronic pain management.

Identifying the risk of opioid misuse in a chronic pain population: the utility of the MMPI-2-RF personality psychopathology five (PSY-5-RF) and higher-order scales

Prescription-related opioid misuse, especially in chronic pain populations, is an ongoing problem and is related to increased mortality. The purpose of this study was to assess the utility of two restructured scales of the MMPI-2-RF: the Personality Psychopathology Five (PSY-5-RF) and the Higher-Order Scales to determine which of their subscales may be beneficial for identifying the risk of opioid misuse in a chronic pain population. A sample of 136 patients with chronic disabling occupational musculoskeletal disorders completed the MMPI-2-RF and the Current Opioid Misuse Measure (COMM) upon admission to a functional restoration program. The PSY-5-RF and H-O subscales were correlated with the baseline COMM scores. Correlation analyses, ROC curve analyses, and multiple binary logistic regression models were developed to determine which subscales were most associated with elevated COMM scores. The results of the regression analyses suggest that Scale elevations on two of the PSY-5-RF Scales and two Higher-Order Scales of the MMPI-2-RF demonstrated significant associations with elevated COMM scores, thus exhibiting the utility of these subscales in identifying the risk of opioid misuse among chronic pain patients. These findings are clinically meaningful in underscoring the importance of identifying specific personality traits as potential predictors of opioid misuse, and identifying those at risk through careful screening. Clinical implications based on each of the PSY-5-RF and H-O scales significantly associated with elevated COMM scores are discussed.

Longitudinal trajectories of prescription opioid misuse in adolescents

BACKGROUND

Adolescent misuse of prescription opioids is hazardous. This study aimed to generate data on prescription opioid misuse trajectories across adolescence and identify risk factors and mechanisms for more dangerous use trajectories.

METHODS

Using a prospective longitudinal cohort repeated measures design, baseline (Fall 2013) and seven semiannual assessments were administered through Spring 2017 in 10 public high schools in Los Angeles, CA. Frequency of past 30-day prescription opioid misuse was captured. Trajectory groups were identified using growth mixture modeling and multinomial logistic regression identified associations between baseline risk factors with membership in each trajectory group.

RESULTS

Overall, 3395 students were evaluated (53.4% female, Mean [SD] age at baseline=14.58[0.40]; range=12.83-16.29). Four discrete misuse trajectories were identified among 1062 students: (1) Minimal/Experimental (infrequent time-limited use; range of estimated mean number of days using prescription opioid across waves=0.0-0.6 days]; N = 705[20.8%]); (2) Low Deescalating (range=2.0-0.7 days; N = 189[5.6%]); (3) Moderate Escalating (range=0.7-3.6 days; N = 108[3.2%]); and (4) Frequent Persistent (range=4.7-9.4 days; N = 60[1.8%]). Students reporting tobacco, cannabis, alcohol use, or impulsivity in 9th grade were more likely to demonstrate membership in the Moderate Escalating trajectory class when compared to 2333 (68.7%) students reporting sustained abstinence. Female sex, peer opioid misuse, alcohol use, other substance use, impulsivity, or delinquent behavior reported in 9th grade was associated with membership in the Frequent Persistent trajectory class.

CONCLUSIONS

Prescription opioid misuse in adolescence appears to follow 4 discrete trajectories, including the potentially problematic Moderate Escalating and Frequent Persistent trajectories. Female sex, peer influences, substance use, and intrapersonal risk factors were associated with membership in these classes.

The effects of early life stress on impulsivity

Elevated impulsivity is a symptom shared by various psychiatric disorders such as substance use disorder, bipolar disorder, and attention-deficit/hyperactivity disorder. However, impulsivity is not a unitary construct and impulsive behaviors fall into two subcategories: impulsive action and impulsive choice. Impulsive choice refers to the tendency to prefer immediate, small rewards over delayed, large rewards, whereas impulsive action involves difficulty inhibiting rash, premature, or mistimed behaviors. These behaviors are mediated by the mesocorticolimbic dopamine (DA) system, which consists of projections from the ventral tegmental area to the nucleus accumbens and prefrontal cortex. Early life stress (ELS) alters both impulsive choice and impulsive action in rodents. ELS also changes DA receptor expression, transmission, and activity within the mesocorticolimbic system. This review integrates the dopamine, impulsivity, and ELS literature to provide evidence that ELS alters impulsivity via inducing changes in the mesocorticolimbic DA system. Understanding how ELS affects brain circuits associated with impulsivity can help advance treatments aimed towards reducing impulsivity symptoms in a variety of psychiatric disorders.

Early life adversity promotes resilience to opioid addiction-related phenotypes in male rats and sex-specific transcriptional changes

Experiencing some early life adversity can have an "inoculating" effect that promotes resilience in adulthood. However, the mechanisms underlying stress inoculation are unknown, and animal models are lacking. Here we used the limited bedding and nesting (LBN) model of adversity to evaluate stress inoculation of addiction-related phenotypes. In LBN, pups from postnatal days 2 to 9 and their dams were exposed to a low-resource environment. In adulthood, they were tested for addiction-like phenotypes and compared to rats raised in standard housing conditions. High levels of impulsivity are associated with substance abuse, but in males, LBN reduced impulsive choice compared to controls. LBN males also self-administered less morphine and had a lower breakpoint on a progressive ratio reinforcement schedule than controls. These effects of LBN on addiction-related behaviors were not found in females. Because the nucleus accumbens (NAc) mediates these behaviors, we tested whether LBN altered NAc physiology in drug-naïve and morphine-exposed rats. LBN reduced the frequency of spontaneous excitatory postsynaptic currents in males, but a similar effect was not observed in females. Only in males did LBN prevent a morphine-induced increase in the AMPA/NMDA ratio. RNA sequencing was performed to delineate the molecular signature in the NAc associated with LBN-derived phenotypes. LBN produced sex-specific changes in transcription, including in genes related to glutamate transmission. Collectively, these studies reveal that LBN causes a male-specific stress inoculation effect against addiction-related phenotypes. Identifying factors that promote resilience to addiction may reveal novel treatment options for patients.

Mind-body approaches targeting the psychological aspects of opioid use problems in patients with chronic pain: evidence and opportunities

Opioids are commonly prescribed for the management of patients with chronic noncancer pain. Despite the potential analgesic benefits of opioids, long-term opioid therapy (LTOT) may be accompanied by problems such as opioid misuse and opioid use disorder (OUD). In this review, we begin with a description of opioid misuse and OUD and the patient-specific factors associated with these problems among patients with chronic pain. We will focus primarily on highlighting the predominant role played by psychological factors in the occurrence of opioid misuse and OUD in these patients. Several psychological factors have been found to be associated with opioid use problems in patients with chronic pain, and evidence indicates that patients presenting with psychological disturbances are particularly at risk of transitioning to long-term opioid use, engaging in opioid misuse behaviors, and developing OUD. The biological factors that might underlie the association between psychological disturbances and opioid use problems in patients with chronic pain have yet to be fully elucidated, but a growing number of studies suggest that dysfunctions in reward, appetitive, autonomic, and neurocognitive systems might be involved. We end with an overview of specific types of psychological interventions that have been put forward to prevent or reduce the occurrence of opioid misuse and OUD in patients with chronic pain who are prescribed LTOT.

Evaluating the impact of age and inflammatory duration on behavioral assessments of nociception

Pain is a prevalent issue for elderly individuals. Unfortunately, it remains unclear how acute and chronic pain differs as a function of age, and surprisingly, there is even disagreement on how the sensory and affective dimensions of pain change with age. Therefore, the current investigation evaluated such age differences with behavioral methodology using a preclinical model of arthritis. The primary factors of interest were age and chronicity of pain using behavioral assessments designed to measure sensory and affective dimensions of pain processing. Mechanical and thermal paw withdrawal thresholds demonstrated unique outcomes associated with sensory processing across age. The processing of pain affect measured by the Place Escape/Avoidance Paradigm (PEAP testing) also demonstrated age related effects. Overall, younger animals appeared more sensitive to nociceptive stimuli than older animals. However, the results from the current study suggest that chronicity of pain can be impactful for how older animals process pain related affect and avoidance. The finding of unique patterns of pain across age and duration of pain highlights the clinical literature. Future research should aim to elucidate mechanisms for affective processing of chronic pain in older subjects.

Predictive variables of prescription opioid misuse in patients with chronic noncancer pain. Development of a risk detection scale: A registered report protocol

BACKGROUND

Opioid therapy is utilized for a broad range of chronic pain conditions. Several studies have highlighted the adverse effects of opioid medication due to the misuse of these drugs. The gradual increase in the use of opioids has become a global phenomenon and is generating social concern. Several treatment guidelines have strongly recommended assessing the risks and benefits of pharmacological treatment with opioids. These guidelines also recommend the psychological assessment of patients with chronic noncancer pain in order to make informed decisions on the advisability of intervention with opioids. Some authors have emphasized the relevance of assessing the risk of opioid misuse in patients with noncancer chronic pain before initiating treatment.

METHODS AND ANALYSIS

Two studies will be conducted, each with a different primary objective. The primary objective of the first study (Study 1) will be to conduct a comprehensive investigation to identify the factors most closely associated with subsequent opioid misuse; and based on the results of Study 1, the primary objective of the second study (Study 2) will be to develop a brief, reliable, valid, and useful instrument that would enable health care providers to make decisions on opioid prescription and on the required level of monitoring and follow-up. These decisions would have positive consequences for patient wellbeing. Study 1 will include a logistic regression analysis to test the hypothetical model. Study 2 will have a longitudinal design and include three assessment sessions in order to develop a measure to assess the risk of prescribed opioid misuse and to analyse its reliability and validity. Participants will be individuals with chronic noncancer pain attending three Pain Units. These individuals will either be undergoing pharmacological treatment that includes opioid analgesics (Study 1, N = 400) or are going to commence such treatment (Study 2, N = 250).

Borderline Personality Disorder Features and Risk for Prescription Opioid Misuse in a Chronic Pain Sample: Roles for Identity Disturbances and Impulsivity

Although borderline personality disorder (BPD) is associated with both chronic pain and substance abuse, little research examines how BPD features in chronic pain patients may constitute a risk factor for misuse of prescription opioids, and no prior research has examined which particular component(s) of BPD might put chronic pain patients at risk-an oversight that undermines prevention and treatment of such problematic opioid use. In a cross-sectional study of patients in treatment for chronic pain (N = 147), BPD features were associated with several measures of prescription opioid misuse, even controlling for pain severity and interference. Specifically, the identity disturbances and self-harmful impulsivity facets of BPD were most consistently associated with opioid misuse, and exploratory analyses suggested that these factors may be interactive in their effects. Together, these results suggest that BPD features-especially unstable identity and self-harmful impulsivity-play a unique role in problematic prescription opioid use in chronic pain settings.

Behavioral predictors of individual differences in opioid addiction vulnerability as measured using i.v. self-administration in rats

BACKGROUND

Like other forms of psychopathology, vulnerability to opioid addiction is subject to wide individual differences. Animal behavioral models are valuable in advancing our understanding of mechanisms underlying vulnerability to the disorder's development and amenability to treatment.

METHODS

This review provides an overview of preclinical work on behavioral predictors of opioid addiction vulnerability as measured using the intravenous (i.v.) self-administration (SA) model in rats. We also highlight several new approaches to studying individual differences in opioid addiction vulnerability in preclinical models that could have greater sensitivity and lead to more clinically relevant findings.

RESULTS AND CONCLUSIONS

Evidence for the relationship between various behavioral traits and opioid SA in the preclinical literature is limited. With the possible exceptions of sensitivity to opioid agonist/withdrawal effects and stress reactivity, predictors of individual differences in SA of other drugs of abuse (e.g. sensation-seeking, impulsivity) do not predict vulnerability to opioid SA in rats. Refinement of SA measures and the use of multivariate designs and statistics could help identify predictors of opioid SA and lead to more clinically relevant studies on opioid addiction vulnerability.

Sex-specific risk profiles for substance use among college students

INTRODUCTION

Growing evidence indicates sex and gender differences exist in substance use. Framed by a lifecourse perspective, we explored prospectively by sex the effects of distal and proximal factors on the initiation of drug use in college.

METHODS

College students without prior drug use (n = 5,120 females; n = 2,951 males) were followed longitudinally across 4 years. Analyses were estimated as a multigroup survival analysis separately by sex within a latent variable SEM framework with illicit drug use (6 or more times in past year) as the latent factor.

RESULTS

More males initiated drug use (8.5%) than females (6.4%, χ2 (1) = 10.351, p = .001), but less so for Black males (AOR 0.33, 95% CI [0.18, 0.60]) and females (0.35 [0.23, 0.54]). Students initiating drug use more likely included students smoking cigarettes at baseline (males 1.40 [1.23, 1.59]; females 1.43 [1.24, 1.64]), using alcohol (males 1.04 [1.02, 1.06]; females 1.04 [1.02, 1.06]), or having cannabis using peers (males 1.79 [1.52, 2.11]; females 1.70 [1.49, 1.93]). Impulsivity domain associations differed by sex [negative urgency: females (1.23 [1.02, 1.49) and sensation seeking: males (1.33 [1.01, 1.75])]. History of unwanted/uncomfortable sexual experience predicted drug use for males (1.60 [1.09, 2.35]) and females (1.95 [1.45, 2.62]) but physical assault only for females (1.45 [1.08, 1.94]). Mood symptoms predicted drug use only for males [depression (0.73 [0.56, 0.95]); anxiety (1.40 [1.04, 1.89])].

CONCLUSIONS

Risk factors for initiating drug use during college differ by sex. As substance use during early age predisposes one for addiction, sex- and gender-informed interventions for young adults are needed.

Lack of Premeditation Predicts Aberrant Behaviors Related to Prescription Opioids in Patients with Chronic Pain: A Cross-Sectional Study

OBJECTIVE

In light of the opioid epidemic, there is a need to identify factors that predict aberrant opioid behaviors including misuse and abuse. Impulsivity has been extensively studied in addiction literature, but not in the context of opioid misuse. Hence, this study aimed to identify which of the impulsivity facets (negative urgency, positive urgency, sensation seeking, lack of perseverance, and lack of premeditation) would predict current aberrant opioid-related behaviors in patients with chronic pain.

METHODS

Data were collected through an online survey from patients with chronic pain who visited a tertiary pain clinic. Patients were predominately female (74%), middle aged (M = 55 years), and White/Caucasian (84%). Upon consent, they completed a series of surveys including UPPS-P Impulsive Behavior Scale, the Current Opioid misuse Measure, Pain Catastrophizing Scale, PROMIS-anxiety, depression, and physical function, and a 0-10 numerical pain rating scale. Ordinal regression analyses were conducted to test study hypotheses.

RESULTS

Contrary to expectations, only lack of premeditation predicted higher odds of aberrant opioid-related behaviors in the past 30 days, after controlling for known covariates, and explained 26% of variance. Interestingly, lack of premeditation together with pain catastrophizing as a covariate explained 56% of the variance in aberrant opioid-related behaviors.

DISCUSSION

The current study is the first to identify a potential role of lack of premeditation as an impulsivity facet predicting aberrant opioid-related behaviors among patients with chronic pain.

Implications of the Opioid Crisis for the American Disability Community

Purpose

The profession of rehabilitation counseling has long been responsive to emerging disabilities. To date, however, the profession's attention and response to the ongoing opioid crisis in the United States has been incommensurate with the scope and detriment of opioids and opioid use disorder (OUD) on Americans with disabilities. The opioid crisis, including the overuse, abuse, and overdose rates associated with prescription and illegal opioids, affects people of all ages and backgrounds. However, people with disabilities are at increased risk for developing OUDs, and they experience greater barriers to OUD treatment than people without disabilities.

Method

This article describes the origins and development of this crisis, the relationship between disability and increased risk for OUD, and the barriers to treatment that exist. We then evaluate the role of rehabilitation counseling, including the need for further action in advocacy, research, education, and policy.

Results and Conclusions

Throughout this article, we encourage a more urgent and concerted response than seems to be the case presently.

CANUE: A Theoretical Model of Pain as an Antecedent for Substance Use

BACKGROUND

Pain and substance use are frequently comorbid and have been shown to exert bidirectional effects. Self-medication of pain and distress via substance use is common and can be understood via negative reinforcement, ultimately strengthening the pathway between pain to substance use over time. As such, a testable model of the potentially modifiable candidate mechanisms that underlie the pain to substance use pathway is needed.

PURPOSE

This review proposes a testable model of pain as an antecedent to substance use to guide future research and inform clinical practice.

METHODS

An integrative review of current evidence regarding pain, substance use, and associated risk factors (i.e., negative affect, pain-related attitudes, negative urgency, and substance use outcome expectancies) was conducted.

RESULTS

The Catastrophizing, Anxiety, Negative Urgency, and Expectancy (CANUE) model highlights modifiable risk factors for self-medicating pain with substance use, including increased negative affect and maladaptive pain-related attitudes (i.e., pain catastrophizing, pain anxiety, and fear of pain), negative urgency, and substance-related outcome expectancies for pain relief and enhanced pain coping.

CONCLUSIONS

Targeted behavioral and psychological interventions that address these factors may facilitate more adaptive pain-coping responses, thereby reducing the impacts of pain on substance use. Systematic research is needed to evaluate the validity and clinical utility of this model.

The Roles of Emotion Regulation Difficulties and Impulsivity in the Associations between Borderline Personality Disorder Symptoms and Frequency of Nonprescription Sedative Use and Prescription Sedative/Opioid Misuse

Despite evidence of a strong relationship between BPD and substance use problems in general, little research has examined the associations of BPD symptoms with the misuse of sedatives or opioids, and no studies have explored possible factors that may underlie these associations. Thus, this study examined the relationships of BPD symptoms (i.e., the number of BPD criteria with threshold ratings on a diagnostic interview) to nonprescription sedative use, nonprescription opioid use, and prescription sedative/opioid misuse among 194 patients with alcohol and/or cocaine dependence in a residential substance use disorder treatment facility, as well as the roles of two theoretically-relevant factors in these relationships: emotion regulation (ER) difficulties and impulsivity facets. We found significant positive associations between BPD symptoms and nonprescription sedative use, nonprescription opioid use, and prescription sedative/opioid misuse. We also found significant positive indirect relationships of BPD symptoms to nonprescription sedative use through ER difficulties, ab = .04, 95% CI [.003, .09], and to prescription sedative/opioid misuse through two facets of impulsivity: lack of perseverance, ab = .05, 95% CI [.01, .11], and negative urgency, ab = .03, 95% CI [.002, .07]. Findings highlight the differential relevance of ER difficulties and impulsivity dimensions to the relationships of BPD symptoms to nonprescription sedative use and prescription sedative/opioid misuse, respectively, among patients with alcohol and/or cocaine dependence.

High trait impulsivity potentiates the effects of chronic pain on impulsive behavior

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We explored a potential relation between trait and chronic pain-induced impulsivity.

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Low trait impulsivity rats with neuropathic pain perform similarly to controls.

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High trait impulsivity rats are delay intolerant in chronic pain conditions.

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Trait characteristics influence chronic pain comorbid manifestations.

Preclinical studies on impulsive decision-making in chronic pain conditions are sparse and often contradictory. Outbred rat populations are heterogeneous regarding trait impulsivity manifestations and therefore we hypothesized that chronic pain-related alterations depend on individual traits. To test this hypothesis, we used male Wistar-Han rats in two independent experiments. Firstly, we tested the impact of spared nerve injury (SNI) in impulsive behavior evaluated by the variable delay-to-signal test (VDS). In the second experiment, SNI impact on impulsivity was again tested, but in groups previously categorized as high (HI) and low (LI) trait impulsivity in the VDS.

Results showed that in an heterogenous population SNI-related impact on motor impulsivity and delay intolerance cannot be detected. However, when baseline impulsivity was considered, HI showed a significantly higher delay intolerance than the respective controls more prevalent in left-lesioned animals and appearing to result from a response correction on prematurity from VDS I to VDS II, which was present in Sham and right-lesioned animals.

In conclusion, baseline differences should be more often considered when analyzing chronic pain impact. While this study pertained to impulsive behavior, other reports indicate that this can be generalized to other behavioral dimensions and that trait differences can influence not only the manifestation of comorbid behaviors but also pain itself in a complex and not totally understood manner.

Network Alterations in Comorbid Chronic Pain and Opioid Addiction: An Exploratory Approach

The comorbidity of chronic pain and opioid addiction is a serious problem that has been growing with the practice of prescribing opioids for chronic pain. Neuroimaging research has shown that chronic pain and opioid dependence both affect brain structure and function, but this is the first study to evaluate the neurophysiological alterations in patients with comorbid chronic pain and addiction. Eighteen participants with chronic low back pain and opioid addiction were compared with eighteen age- and sex-matched healthy individuals in a pain-induction fMRI task. Unified structural equation modeling (SEM) with Lagrange multiplier (LM) testing yielded a network model of pain processing for patient and control groups based on 19 a priori defined regions. Tests of differences between groups on specific regression parameters were determined on a path-by-path basis using z-tests corrected for the number of comparisons. Patients with the chronic pain and addiction comorbidity had increased connection strengths; many of these connections were interhemispheric and spanned regions involved in sensory, affective, and cognitive processes. The affected regions included those that are commonly altered in chronic pain or addiction alone, indicating that this comorbidity manifests with neurological symptoms of both disorders. Understanding the neural mechanisms involved in the comorbidity is crucial to finding a comprehensive treatment, rather than treating the symptoms individually.

Interrelationship of Opioid Dependence, Impaired Impulse Control, and Depressive Symptoms: An Open-Label Cross-Sectional Study of Patients in Maintenance Therapy

OBJECTIVE

A growing number of studies indicate increased impulsivity in patients with opioid dependence (OD). However, few studies exclude concomitant drug use and consider depression as a comorbidity, both of which can bias results.

AIM

We aimed to compare impulsivity in patients with OD enrolled in maintenance therapy (ICD code F11.22) and well-matched healthy controls taking psychopathological impairments into account. Furthermore, we compared the result to risky behavioral patterns in patients.

METHODS

This cross-sectional study included 50 patients with OD enrolled in either methadone or buprenorphine maintenance therapy and 50 healthy controls matched for gender, age, education, marital status, and premorbid intelligence. Abstinence from benzodiazepines, amphetamines, and cocaine was verified by urine analysis. We used the Barratt Impulsiveness Scale 11 (BIS-11), Beck's Depression Inventory (BDI), the Symptom Checklist 90 Revised (SCL-90R), and the European version of the Addiction Severity Index (EuropASI).

RESULTS

Patients exhibited significantly worse impulse control than healthy individuals. We found no correlation between impulsiveness and reported risky behavior patterns but found a significant correlation between depressive symptoms and psychopathological impairment.

CONCLUSIONS

Patients with OD showed a higher impulsivity than healthy individuals. Impulsivity could be a cause or a consequence of a substance use disorder; further research is warranted to explain this relationship. Impulsivity was associated with depression, an important confounder; future research needs to take this into account.

Borderline Features and Prescription Opioid Misuse in a Substance Use Disorder Treatment Sample

BACKGROUND

An association between borderline personality disorder (BPD) and substance use disorders has been well established. However, very little is known about the relationship between BPD and prescription opioid misuse, specifically.

OBJECTIVES

The relationship between borderline personality disorder features and prescription opioid misuse was examined in a sample of 208 substance use disorder treatment patients in the outpatient level of care.

RESULTS

Controlling for use of alcohol and cannabis, as well as other relevant covariates, we found that BPD features were associated with age of first use of prescription opioids, prescription opioid use disorder symptom count, lifetime use, past 12-month use, problem use, and cravings. Additionally, we found that BPD features were not associated with greater use of medically necessary opioid pain killers as prescribed by a physician; rather the association with BPD was in the greater likelihood of misuse (non-prescribed) of prescription opioid pain killers. The self-harm/impulsivity facet of BPD was most strongly associated with prescription opioid-related variables. Conclusions/Importance: These findings suggest that BPD is related to prescription opioid misuse, above and beyond the tendency to use other drugs of abuse, and that the self-harm impulsivity facet appears to be driving this relationship.

Posttraumatic stress disorder and chronic pain are associated with opioid use disorder: Results from a 2012-2013 American nationally representative survey

BACKGROUND

Chronic pain conditions and posttraumatic stress disorder (PTSD) commonly co-occur and are associated with opioid use disorder (OUD). The aims of this paper were to identify prevalence estimates of OUD among individuals with and without PTSD and assess independent and combined contributions of PTSD and chronic pain conditions on OUD in a nationally representative sample.

METHODS

Data were extracted from 36,309 individuals from the 2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions. Past-year PTSD and OUD were assessed using the Alcohol Use Disorder and Associated Disabilities Interview Schedule-DSM-5 edition. Respondents reported physician-confirmed, past-year chronic pain conditions, categorized into musculoskeletal pain (e.g., arthritis), digestive pain (e.g., pancreatitis), and nerve pain (e.g., reflex sympathetic dystrophy). We examined the weighted prevalence of OUD among those with and without PTSD. Multiple logistic regressions examined the association between PTSD and chronic pain conditions on OUD.

RESULTS

The prevalence of OUD was higher among those with PTSD than those without. Comorbid PTSD/musculoskeletal pain and PTSD/nerve pain conditions were associated with increased odds of OUD, compared to those with neither PTSD nor chronic pain conditions. Digestive pain conditions were not associated with OUD. Comorbid PTSD/musculoskeletal pain conditions demonstrated an additive relationship on OUD compared to musculoskeletal pain conditions and PTSD alone.

CONCLUSIONS

Results reveal that musculoskeletal pain and nerve pain conditions are associated with increased odds of OUD, but only musculoskeletal pain conditions display an additive relationship on OUD when combined with PTSD. These findings have implications for opioid management and screening among those with comorbid conditions.

Locomotor activity does not predict individual differences in morphine self-administration in rats

Understanding factors contributing to individual differences in opioid addiction vulnerability is essential for developing more effective preventions and treatments. Sensation seeking has been implicated in addiction to several drugs of abuse, yet its relationship with individual differences in opioid addiction vulnerability has not been well established. The primary goal of this study was to evaluate the relationship between locomotor activity in a novel environment, a preclinical model of sensation-seeking, and individual differences in acquisition of i.v. morphine self-administration (SA) in rats. A secondary goal was to evaluate the relationship between activity and elasticity of demand (reinforcing efficacy) for morphine measured using a behavioral economic approach. Following an initial locomotor activity screen, animals were allowed to acquire morphine SA at a unit dose of 0.5 mg/kg/infusion in 4 hour/day sessions (Experiment 1) or 0.2 mg/kg/infusion in 2 hour/day sessions (Experiment 2) until infusion rates were stable. Unit price was subsequently manipulated via progressive reductions in unit dose (Experiment 1) or increases in response requirement per infusion (Experiment 2). Activity levels were not correlated with acquisition of morphine SA in either experiment. Morphine consumption was generally well described by an exponential demand function in both experiments (R² values > 0.95 for rats as a group), but activity did not correlate with behavioral economic measures. Locomotor activity in a novel environment did not predict individual differences in acquisition of morphine SA. These data complement findings from some human studies and suggest that the role of sensation seeking in individual differences in opioid addiction vulnerability may be limited.

To take or not to take: the association between perceived addiction risk, expected analgesic response and likelihood of trying novel pain relievers in self-identified chronic pain patients

BACKGROUND AND AIMS

Probability discounting refers to the effect of outcome uncertainty on decision making. Using probability discounting, we examined the degree to which self-identified chronic pain patients (CPP) were likely to try a novel analgesic medication given increasing addiction risk. We postulated that propensity for opioid misuse, trait impulsivity and previous opioid experience would be associated positively with likelihood of risky medication use.

DESIGN

This cross-sectional on-line study determined state/trait associations with addiction-related medication decisions in CPP.

SETTING

US-based CPP participated via Amazon Mechanical Turk; data were collected and analyzed in Baltimore, Maryland.

PARTICIPANTS

A total of 263 CPP (70.6% female) participated in the study from 12-13 December 2014.

MEASUREMENTS

CPP responded to the Benefit versus Addiction Risk Questionnaire (BARQ) assessing likelihood of taking a hypothetical once-daily oral analgesic medication as a function of two factors: risk of addiction (0-50%) and duration of expected complete pain relief (3, 30 or 365 days). The primary outcome was the BARQ, quantified as area under the curve (AUC). Grouping of CPP at high or low risk for opioid misuse was based on the Screener and Opioid Assessment for Patients with Pain-Revised (SOAPP-R). Predictors included previous experience with opioids, as well as various measures of chronic pain and mental health.

FINDINGS

Across hypothetical addiction risk assessed in the BARQ, the likelihood of taking a novel analgesic medication was elevated significantly in patients with high (≥18; n = 137) versus low (<18; n = 126) SOAPP-R scores [P < 0.001; 3-day: Cohen's d = 0.66, 95% confidence interval (CI) = 0.63, 0.69; 30-day: d = 0.74, 95% CI = 0.71, 0.78; 365-day: d = 0.75, 95% CI = 0.72, 0.79].

CONCLUSIONS

In the United States, self-identified chronic pain patients (CPP) at higher risk for opioid misuse were more likely to report willingness to try a novel analgesic despite increasing addiction risk than CPP with low risk of opioid misuse.

Examination of the validity and reliability of the French version of the Brief Self-Control Scale

This study aims to develop and to validate a French version of the Brief Self-Control Scale (BSCS; Tangney et al., 2004). This instrument is usually applied as a unidimensional self-report measure for assessing trait self-control, which captures one's dispositional ability to resist short-term temptation in order to reach more valuable long-term goals. Data were collected from two independent samples of French-speaking individuals (n₁ = 287; n₂ = 160). Results indicated that the French version of the BSCS can be treated as unidimensional, like the original questionnaire. Data also showed consistent acceptable reliability and reasonable test-retest stability. Acceptable external validity of constructs was supported by relationships with self-reported measures of impulsivity (UPPS), including urgency, lack of premeditation, and lack of perseverance. Overall, the findings suggest that the average score of the French version of the BSCS is a viable option for assessing trait self-control in French speaking populations.

Risk Factors for Symptoms of Prescription Opioid Misuse: Do Older Adults Differ from Younger Adult Patients?

Limited research is available regarding the health risks associated with opioid medication misuse among middle age (50-64 years) and older adults (65 and older). Understanding the misuse symptom risk profiles of these populations has potential to advance the national opioid epidemic response. A survey was conducted in four community pharmacies in southwestern Pennsylvania among adult, non-cancer patients filling opioid medications (N = 318) regarding opioid medication misuse symptoms and misuse risk factors. Descriptive and multivariate statistical analyses compared respondent characteristics, misuse symptoms, and misuse risks among those 65 and older, 50 to 64, and those less than 50 years old. Those 65 and older (Incidence Rate Ratio [IRR] = 2.4, 95% CI = 1.46-3.95) and those 50 to 64 years (IRR = 1.26, 95% CI = 1.03-1.54) who reported illicit drug use had increased rates of misuse symptoms. Those 50-64 with posttraumatic stress disorder also had an increased rate of misuse symptoms (IRR = 1.29, 95% CI = 1.08-1.54). Misuse behaviors of those 65 and older and 50-64 involved shortening time between dosages (≥65 = 11.4%, 50-64 = 27.6%), taking higher dosages than prescribed (≥65 = 11.4%, 50-64 = 13.6%), and early refills (≥11.8%, 50-64 = 12.7%). Gerontological social workers must continue to work to understand and identify individuals engaged in misuse in order to develop and provide age appropriate care.

Neuroinflammation-a co-occurring phenomenon linking chronic pain and opioid dependence

Chronic pain is a disease that encompasses both sensory and emotional elements. Opioids are highly effective analgesics because they target both of these elements, by inhibiting pain pathways and alleviating negative affect (including depression) by engaging reward or hedonic pathways. Unfortunately, chronic opioid use is limited by the development of unwanted side effects, such as tolerance, hyperalgesia, and abuse liability. Thus, the challenge of providing effective pain treatment while minimizing these unwanted side effects is an ongoing issue with significant clinical and societal impact. In this review, we posit that neuroinflammation within the central nervous system is a shared phenomenon between chronic pain and opioids that contributes to pain sensitization and negative affect. The implications for pain progression, addiction liability, and alternative treatment strategies are discussed.

Neurobiology of opioid dependence in creating addiction vulnerability

Opioid drugs are potent modulators of many physiological and psychological processes. When given acutely, they can elicit the signature responses of euphoria and analgesia that societies have coveted for centuries. Repeated, or chronic, use of opioids induces adaptive or allostatic changes that modify neuronal circuitry and create an altered normality — the “drug-dependent” state. This state, at least that exhibited by those maintained continuously on long-acting opioid drugs such as methadone or buprenorphine, is generally indistinguishable from the drug-naïve state for most overt behaviors. The consequences of the allostatic changes (cellular, circuit, and system adaptations) that accompany the drug-dependent state are revealed during drug withdrawal. Drug cessation triggers a temporally orchestrated allostatic re-establishment of neuronal systems, which is manifested as opposing physiological and psychological effects to those exhibited by acute drug intoxication. Some withdrawal symptoms, such as physical symptoms (sweating, shaking, and diarrhea) resolve within days, whilst others, such as dysphoria, insomnia, and anxiety, can linger for months, and some adaptations, such as learned associations, may be established for life. We will briefly discuss the cellular mechanisms and neural circuitry that contribute to the opioid drug-dependent state, inferring an emerging role for neuroinflammation. We will argue that opioid addictive behaviors result from a learned relationship between opioids and relief from an existing or withdrawal-induced anxiogenic and/or dysphoric state. Furthermore, a future stressful life event can recall the memory that opioid drugs alleviate negative affect (despair, sadness, and anxiety) and thereby precipitate craving, resulting in relapse. A learned association of relief of aversive states would fuel drug craving in vulnerable people living in an increasingly stressful society. We suggest that this route to addiction is contributive to the current opioid epidemic in the USA.