Comparative profiles of men and women with opioid dependence: results from a national multisite effectiveness trial

Fentanyl self-administration is accelerated by methamphetamine co-use and results in worsened hypodopaminergia in male, but not female rats

Combined use of fentanyl and methamphetamine (FENT + METH) has increased in recent years and has been documented in a growing number overdose deaths each year. The impact of FENT + METH on behavior and neurobiology is not well understood. In this study, male and female Long Evans rats were tested on a limited access, fixed ratio 1 self-administration schedule for increasing doses (1.25-5 μg/kg/infusion; iv) of fentanyl, with and without a single dose (0.1 mg/kg/infusion; iv) of methamphetamine, for 15 days. FENT + METH abolished dose responsiveness to fentanyl in all rats and accelerated intake in males, resulting in patterns of responding that may be more likely to result in adverse effects. Ex vivo slice voltammetry in the nucleus accumbens core showed decreases in dopamine release and reuptake (Vmax) following FENT + METH exposure, compared with saline, fentanyl, and methamphetamine alone groups at baseline parameters. Further, significant decreases in dopamine release were observed across a range of stimulation intensities following FENT + METH exposure. Overall, male and female rats displayed sex-specific behavioral and neurobiological responses to FENT + METH exposure, with males displaying increased vulnerability.

Examining the effects of the HIV-1 protein Tat and morphine on antiretroviral accumulation and distribution within the brain

Despite combination antiretroviral therapy effectively suppressing HIV within the periphery, neuro-acquired HIV (neuroHIV) remains a significant problem and approximately half of people living with HIV will experience HIV-associated neurocognitive disorders (HAND). Concurrent opioid use exacerbates neuroHIV by promoting neuroinflammation, neuronal injury and synaptodendritic culling, viral replication, and potentially altering antiretroviral concentrations within the brain. The present study examined the effects of HIV and morphine co-exposure on the accumulation and spatial distribution of antiretroviral drugs across multiple regions within the brain in an HIV-1 Tat transgenic mouse model by using infrared-matrix-assisted laser desorption electrospray ionization mass spectrometry imaging (IR-MALDESI MSI). Morphine exposure uniquely decreased antiretroviral concentrations in anterior cerebral (primary motor and somatosensory) cortices, corpus collosum (anterior forceps), caudoputamen, nucleus accumbens, and posterior regions including the hippocampus, corpus callosum (main body), cerebral cortex (somatosensory and auditory cortices), thalamus, and hypothalamus. Interestingly, male mice experienced greater morphine-associated decreases in antiretroviral concentrations than females. The study also assessed whether changes in antiretroviral concentrations were linked with inflammation in astroglia, assessed through the measurement of astroglial activation using glial fibrillary acidic protein (GFAP) as a marker. Alterations in antiretroviral concentrations co-registering with areas of astroglial activation exhibited sex-specific treatment differences. This study highlights the intricate interplay between HIV, opioids, and antiretroviral drugs within the CNS, elucidating distinct regional and sex variations in responsiveness. Our findings emphasize the identification of vulnerabilities within the neural landscape and underscore the necessity of carefully monitoring opioid use to maintain the efficacy of antiretroviral therapies.

BNST CRF receptor type 1 modulates mechanical hypersensitivity induced by adolescent alcohol exposure in adult female mice

RATIONALE

Alcohol exposure during adolescence has been linked to long-lasting behavioral consequences, contributing to the development of alcohol use disorder. Negative affect and chronic pain during alcohol withdrawal are critical factors influencing problematic alcohol use and relapse. Our previous research demonstrated that adolescent intermittent ethanol (AIE) vapor exposure elicits sex-specific negative affect-like behavior in adult mice following stress exposure. Additionally, AIE induces persistent mechanical hypersensitivity, which is accompanied by increased activation of corticotropin-releasing factor receptor type 1 (CRFR1) neurons in the dorsolateral bed nucleus of the stria terminalis (dlBNST).

OBJECTIVES

This study extends previous work by investigating plasma corticosterone levels and CRFR1 protein expression in the dlBNST following restraint stress exposure in adult mice with an AIE history. We also aim to explore the role of dlBNST CRFR1 signaling in mediating negative affect-like behavior and mechanical hypersensitivity.

RESULTS

Female mice exhibited elevated plasma corticosterone levels compared to males following restraint stress. Moreover, females with AIE history showed higher expression of CRFR1 protein in the dlBNST compared to air controls. Antagonism of CRFR1 in the dlBNST blocked AIE-induced mechanical hypersensitivity in adult females but did not affect stress-induced negative affect-like behavior. In alcohol-naïve females, intra-dlBNST administration of a CRFR1 agonist induced mechanical hypersensitivity.

CONCLUSIONS

These findings provide new insights into the neurobiological mechanisms underlying stress-induced negative affect and pain-related behavior, both influenced by a history of adolescent alcohol exposure. The results suggest that CRFR1 antagonists warrant further investigation for their potential in addressing alcohol-related chronic pain.

Sex-specific Concordance of Striatal Transcriptional Signatures of Opioid Addiction in Human and Rodent Brains

Opioid use disorder (OUD) has emerged as a severe, ongoing public health emergency. Current, frontline addiction treatment strategies fail to produce lasting abstinence in most users. This underscores the lasting effects of chronic opioid exposure and emphasizes the need to understand the molecular mechanisms of drug seeking and taking, but also how those alterations persist through acute and protracted withdrawal. Here, we used RNA sequencing in post-mortem human tissue from males (n=10) and females (n=10) with OUD and age and sex-matched comparison subjects. We compared molecular alterations in the nucleus accumbens (NAc) and dorsolateral prefrontal cortex (DLPFC) between humans with OUD and rodent models across distinct stages of opioid use and withdrawal (acute and prolonged) using differential gene expression and network-based approaches. We found that the molecular signature in the NAc of females with OUD mirrored effects seen in the NAc of female mice at all stages of exposure. Conversely, males with OUD showed strong overlap in expression profile with rats in acute withdrawal. Co-expression networks involved in post-transcriptional modification of RNA and epigenetic modification of chromatin state. This study provides fundamental insight into the converging molecular pathways altered by opioids across species. Further, this work helps to disentangle which alterations observed in humans with OUD are driven by acute drug exposure and which alterations are consequences of chronic exposure.

Magnitude and predictors of elasticity of demand for morphine are similar in male and female rats

Introduction

Sex differences in vulnerability to opioid use disorder (OUD) have been reported in some clinical and preclinical studies, but findings are mixed and further research is needed in this area. The goal of this study was to compare elasticity of demand (reinforcement efficacy) in an i.v. morphine self-administration (SA) model in male and female rats using a translationally relevant behavioral economics approach. Rate of acquisition and predictors of individual differences in demand (e.g., cumulative morphine infusions during acquisition) were also evaluated in both sexes.

Materials methods and results

Acquisition of morphine SA (0.4 mg/kg/infusion) under a fixed ratio (FR) 1 schedule of reinforcement was slower and infusions earned were lower in females than in males (n = 30-31/sex), but infusions earned did not differ between sexes during the FR 2 and FR 3 phases of acquisition. Increases in the FR response requirement across sessions during demand testing (FR 1-FR 96) resulted in a progressive reduction in morphine infusions in both sexes. Morphine consumption was well-described by an exponential demand function in both sexes and was associated with considerable individual vulnerability. There were no sex differences in elasticity of demand (rate of decline in morphine consumption with increasing price) or intensity of demand (consumption at zero price). A higher number of infusions earned during the FR 2 and FR 3 phases of acquisition and greater maximum response rates during demand testing were associated with lower demand elasticity (i.e., greater reinforcing efficacy) in both males and females, whereas other relationships were sex-specific (e.g., higher intensity of demand was associated with lower elasticity of demand in males but not in females).

Conclusion

Our findings indicate similar elasticity of demand and predictors of individual differences in demand for morphine in male and female rats, although sex differences were observed in initial rate of acquisition and in some correlations between morphine SA measures. These data are consistent with findings of similar OUD vulnerability in males and females in some human and animal studies.

Sex differences in comorbid pain and opioid use disorder: A scoping review

Opioid use disorder (OUD) and chronic pain are commonly co-occurring disorders which can exacerbate each other. Sex/gender differences have been shown in aspects of the clinical course and biological underpinnings of both OUD and chronic pain. The purpose of this scoping review is to summarize literature which has addressed sex/gender differences in relation to the confluence of OUD and chronic pain. This review focused on peer-reviewed journal articles with human subjects and addressing (a) opioid misuse, chronic opioid use or opioid use disorder (OUD), (b) chronic or persistent pain and (c) sex/gender differences in relation to OUD and/or chronic pain. Of the 146 papers identified by the search strategy, 30 met the criteria for inclusion. Charting focused on a priori themes of chronic pain, opioid misuse/OUD and sex/gender in sample, predictor and outcome variables, and key study findings. The majority of research identified was cross-sectional in nature, and sex/gender differences and treatment effects were largely included as post-hoc analyses. Together, the results of this early work align with higher prevalence for OUD in men/males and chronic pain in women/females, while adding critical information with respect to potential sex/gender differences in the development and treatment of their co-occurrence across a range of biological and psychosocial factors. Findings underline the importance of considering sex and gender in the intersection of the development and treatment of OUD and chronic pain.

Mitigating Sociodemographic Bias in Opioid Use Disorder Prediction: Fairness-Aware Machine Learning Framework

BACKGROUND

Opioid use disorder (OUD) is a critical public health crisis in the United States, affecting >5.5 million Americans in 2021. Machine learning has been used to predict patient risk of incident OUD. However, little is known about the fairness and bias of these predictive models.

OBJECTIVE

The aims of this study are two-fold: (1) to develop a machine learning bias mitigation algorithm for sociodemographic features and (2) to develop a fairness-aware weighted majority voting (WMV) classifier for OUD prediction.

METHODS

We used the 2020 National Survey on Drug and Health data to develop a neural network (NN) model using stochastic gradient descent (SGD; NN-SGD) and an NN model using Adam (NN-Adam) optimizers and evaluated sociodemographic bias by comparing the area under the curve values. A bias mitigation algorithm, based on equality of odds, was implemented to minimize disparities in specificity and recall. Finally, a WMV classifier was developed for fairness-aware prediction of OUD. To further analyze bias detection and mitigation, we did a 1-N matching of OUD to non-OUD cases, controlling for socioeconomic variables, and evaluated the performance of the proposed bias mitigation algorithm and WMV classifier.

RESULTS

Our bias mitigation algorithm substantially reduced bias with NN-SGD, by 21.66% for sex, 1.48% for race, and 21.04% for income, and with NN-Adam by 16.96% for sex, 8.87% for marital status, 8.45% for working condition, and 41.62% for race. The fairness-aware WMV classifier achieved a recall of 85.37% and 92.68% and an accuracy of 58.85% and 90.21% using NN-SGD and NN-Adam, respectively. The results after matching also indicated remarkable bias reduction with NN-SGD and NN-Adam, respectively, as follows: sex (0.14% vs 0.97%), marital status (12.95% vs 10.33%), working condition (14.79% vs 15.33%), race (60.13% vs 41.71%), and income (0.35% vs 2.21%). Moreover, the fairness-aware WMV classifier achieved high performance with a recall of 100% and 85.37% and an accuracy of 73.20% and 89.38% using NN-SGD and NN-Adam, respectively.

CONCLUSIONS

The application of the proposed bias mitigation algorithm shows promise in reducing sociodemographic bias, with the WMV classifier confirming bias reduction and high performance in OUD prediction.

Racial and ethnic inequities in substance use treatment among women with opioid use disorder

Background: Research describes inequities in substance use treatment, but few studies focus specifically on racial and ethnic disparities in a range of aspects of substance use treatment among women with opioid use disorder (OUD).Objective: To examine whether substance use treatment (i.e. receipt, sources, barriers) differs by race and ethnicity among women with opioid use disorder (OUD) and to identify factors associated with treatment gap (i.e. needing treatment but not receiving it).Methods: We performed cross-sectional analyses using National Survey on Drug Use and Health 2015-2019 data, restricted to non-Hispanic Black, non-Hispanic White, and Hispanic women with past-year OUD (unweighted n = 1089). We estimated the prevalence of aspects of treatment among racial and ethnic groups, and used modified Poisson regression to estimate correlates of reported treatment gap.Results: Approximately 68% of White versus 87% of Black and 81% of Hispanic women with OUD had a treatment gap (p-value 0.0034). Commonly reported barriers to treatment included prioritization, affordability, and stigma. Older age was associated with lower prevalence of treatment gap among all women [prevalence ratio (PR) = 0.83, and 95% confidence interval (CI): 0.76, 0.92], while criminal legal involvement and healthcare coverage was associated with a lower prevalence of treatment gap among Hispanic and White women only (past year arrest: Hispanic women PR = 0.38, 95% CI: 0.17, 0.86; White women PR = 0.62, 95% CI: 0.47, 0.82).Conclusions: Receipt of treatment is low among women with OUD, especially Black and Hispanic women. Intersectional intervention approaches are needed to increase access and reduce inequities.

Delivery Outcomes Among Pregnant Women With Comorbid Psychiatric and Substance Use Disorders Receiving Comprehensive Treatment

BACKGROUND: Pregnant women with substance use disorders (SUDs) are at risk for adverse delivery outcomes, and some of these women have psychiatric comorbidities that increase this risk. AIMS: Although comprehensive care models offering prenatal care services and substance abuse treatment have been found to positively affect delivery outcomes for pregnant women with SUDs, there is a dearth of research to support such models for women who have psychiatric comorbidities. METHODS: A secondary data analysis was conducted to understand the relationship between pretreatment psychiatric comorbidity and delivery outcomes for pregnant clients with SUDs receiving comprehensive treatment. We analyzed two groups of pregnant women with SUDs and hypothesized that women with psychiatric comorbidities would have worse neonatal and maternal outcomes compared with those who did not have any pretreatment psychiatric comorbidity. Regression models were used to examine changes in delivery outcome criteria (birthweight, neonatal abstinence syndrome, maternal urine toxicology screens at delivery, and hospital length of stay) in relation to psychiatric comorbidity among a sample of 74 mother-baby dyads receiving comprehensive care treatment. RESULTS: Results did not support our hypothesis as delivery outcomes were statistically similar for both groups. CONCLUSION: Findings suggest comprehensive care can reduce the risk of negative delivery outcomes among women with SUDs who have psychiatric comorbidities. Treatment and research implications are provided.

Daily treatment with the dual orexin receptor antagonist DORA-12 during oxycodone abstinence decreases oxycodone conditioned reinstatement

Chronic opioid use disturbs circadian rhythm and sleep, encouraging opioid use and relapse. The orexin (OX) system is recruited by opioids and regulates physiological processes including sleep. Dual OX receptor antagonists (DORAs), developed for insomnia treatment, may relieve withdrawal-associated sleep disturbances. This study investigated whether DORA-12, a recently developed DORA, reduces physiological activity disturbances during oxycodone abstinence and consequently prevents oxycodone-seeking behavior. Male and female Wistar rats were trained to intravenously self-administer oxycodone (0.15 mg/kg, 21 sessions; 8 h/session) in the presence of a contextual/discriminative stimulus (SD). The rats were subsequently housed individually (22 h/day) to monitor activity, food and water intake. They received DORA-12 (0-30 mg/kg, p.o.) after undergoing daily 1-h extinction training (14 days). After extinction, the rats were tested for oxycodone-seeking behavior elicited by the SD. Hypothalamus sections were processed to assess oxycodone- or DORA-12-associated changes to the OX cell number. In males, oxycodone-associated increases in activity during the light-phase, reinstatement, and decreases in the number of OX cells observed in the vehicle-treated group were not observed with DORA-12-treatment. Oxycodone-associated increases in light-phase food and water intake were not observed by day 14 of 3 mg/kg DORA-12-treatment and dark-phase water intake was increased across treatment days. In females, OX cell number was unaffected by oxycodone or DORA-12. Three and 30 mg/kg DORA-12 increased females' day 7 dark-phase activity and decreased reinstatement. Thirty mg/kg DORA-12 reduced oxycodone-associated increases in light-phase food and water intake. The results suggest that DORA-12 improves oxycodone-induced disruptions to physiological activities and reduces relapse.

Guideline No. 443a: Opioid Use Throughout Women's Lifespan: Fertility, Contraception, Chronic Pain, and Menopause

OBJECTIVE

To provide health care providers with the best evidence on opioid use and women's health. Areas of focus include general patterns of opioid use and safety of use; care of women who use opioids; stigma, screening, brief intervention, and referral to treatment; hormonal regulation; reproductive health, including contraception and fertility; sexual function; perimenopausal and menopausal symptoms; and chronic pelvic pain syndromes.

TARGET POPULATION

The target population includes all women currently using or contemplating using opioids.

OUTCOMES

Open, evidence-informed dialogue about opioid use will lead to improvements in patient care and overall health.

BENEFITS, HARMS, AND COSTS

Exploring opioid use through a trauma-informed approach offers the health care provider and patient with an opportunity to build a strong, collaborative, and therapeutic alliance. This alliance empowers women to make informed choices about their own care. It also allows for the diagnosis and possible treatment of opioid use disorders. Use should not be stigmatized, as stigma leads to poor "partnered care" (i.e., the partnership between the patient and care provider). Therefore, health care providers and patients must understand the potential role of opioids in women's health (both positive and negative) to ensure informed decision-making.

EVIDENCE

A literature search was designed and carried out in PubMed and the Cochrane Library databases from August 2018 until March 2023 using following MeSH terms and keywords (and variants): opioids, illicit drugs, fertility, pregnancy, breastfeeding, and aging.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations).

INTENDED AUDIENCE

All health care providers who care for women.

TWEETABLE ABSTRACT

Opioid use can affect female reproductive function; health care providers and patients must understand the potential role of opioids in women's health to ensure informed decision-making.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Effects of selective dopamine D3 receptor partial agonist/antagonists on oxycodone self-administration and antinociception in monkeys

Recent studies suggest that dopamine D3 receptors (D3R) may be a therapeutic target for opioid use disorders (OUD). This study examined the effects of the D3R partial agonist (±)VK4-40 and the D3R-selective antagonist (±)VK4-116, compared to the mu-opioid receptor antagonist naltrexone (NTX), in nonhuman primate models of OUD and antinociception. Adult male and female (N = 4/sex) cynomolgus monkeys were trained to self-administer oxycodone (0.003-0.1 mg/kg/injection) first under a fixed-ratio (FR) and then a progressive-ratio (PR) schedule of reinforcement during daily 1- and 4-hr sessions, respectively. Under the FR schedule, intravenous NTX (0.01-0.1 mg/kg), (±)VK4-116 (1.0-10 mg/kg), and (±)VK4-40 (1.0-10 mg/kg) were studied in combination with the peak oxycodone dose and a dose on the descending limb of the dose-effect curve; NTX and (±)VK4-40 were also studied at the peak of the PR dose-response curve (N = 4). Following saline extinction, each compound was examined on oxycodone-induced reinstatement. Finally, these compounds were assessed in adult male rhesus monkeys (N = 3) in a warm-water (38 °C, 50 °C, 54 °C) tail withdrawal assay. NTX decreased responding on the peak of the FR oxycodone dose-response curve, but increased responding on the descending limb. (±)VK4-40, but not (±)VK4-116, significantly decreased peak oxycodone self-administration; (±)VK4-40 did not increase responding on the descending limb. NTX and (±)VK4-40, but not (±)VK4-116, attenuated oxycodone-induced reinstatement. Under PR responding, NTX and (±)VK4-40 decreased breakpoints. Oxycodone-induced antinociception was attenuated by NTX, but not by (±)VK4-40 or (±)VK4-116. Together, these results suggest that further research evaluating the effects of (±)VK4-40 as a novel pharmacotherapy for OUD is warranted.

Drug Safety and Suicidality Risk of Chronic Pain Medications

Chronic pain is one of the main leading causes of disability in the world at present. A variety in the symptomatology, intensity and duration of this phenomenon has led to an ever-increasing demand of pharmacological treatment and relief. This demand for medication, ranging from well-known groups, such as antidepressants and benzodiazepines, to more novel drugs, was followed by a rise in safety concerns of such treatment options. The validity, frequency, and diversity of such concerns are discussed in this paper, as well as their possible effect on future prescription practices. A specific caution is provided towards the psychological safety and toll of these medications, regarding suicidality and suicidal ideation. Most significantly, this paper highlights the importance of pharmacovigilance and underscores the necessity of surveillance programs when considering chronic pain medication.

Identifying the most common barriers to opioid agonist treatment in an Australian setting

BACKGROUND

Opioid use disorder is a public health concern in Australia. Opioid agonist treatment (OAT) is effective at treating and minimising harm from opioid use disorder, yet is underused in Australia due to client barriers. Although these barriers have been reported, the barriers that are most important to clients is unclear. The aim of this paper was to determine the most important OAT barriers to Australian clients.

METHODS

A cross-sectional, self-completed survey was given to 204 opioid-dependent clients who attended needle and syringe sites in Australia. Participants were given 15 OAT barrier statements, which they answered using a 5-point Likert scale (1=strongly disagree, 2=disagree, 3=neutral, 4=agree and 5=strongly agree). The Likert scale data are presented using the count method and the mean Likert scores (for the whole sample and for subgroups).

RESULTS

The two methods determined that the four most important barriers to OAT were stigma, lack of support services, no flexibility and enjoy using opioids. Furthermore, those who used prescription opioids (compared with heroin) were female or non-binary (compared with male), were not currently using OAT (compared with current OAT), were younger (compared with older) and had high dependence scores (compared with low dependence scores) were impacted more by certain OAT barriers.

CONCLUSIONS

Policies around improving support services, reducing stigma and increasing flexibility would be beneficial to reduce barriers to OAT in Australia. Second, certain groups were more vulnerable to OAT barriers, emphasising the importance to better tailor opioid treatment programs to these specific populations to increase treatment engagement.

Focus on fentanyl in females: Sex and gender differences in the physiological and behavioral effects of fentanyl

The prevalence of opioid use disorder and overdose continues to harm the U.S. population and is further exacerbated by the use of the synthetic opioid, fentanyl, and its analogs. Gender differences in the effects of fentanyl are not well understood. The present article reviews evidence for gender and sex differences in the physiological and behavioral effects of fentanyl in humans and animals. Biological sex seems to be a foundational driver in addiction vulnerability and affects mechanisms related to opioid use including fentanyl. Fentanyl has distinct pharmacodynamics and enhanced efficacy relative to other opioids that highlights the need to investigate how females may be uniquely altered by its use. Behavioral and physiological responses to fentanyl are found to differ by sex and gender in many cases, including outputs like affective symptoms, analgesia, tolerance, and withdrawal emphasizing the need for further research about the role of biological sex on fentanyl use.

Gender-Specific Interactions in a Visual Object Recognition Task in Persons with Opioid Use Disorder

Opioid use disorder (OUD)-associated overdose deaths have reached epidemic proportions worldwide over the past two decades, with death rates for men reported at twice the rate for women. Using a controlled, cross-sectional, age-matched (18-56 y) design to better understand the cognitive neuroscience of OUD, we evaluated the electroencephalographic (EEG) responses of male and female participants with OUD vs. age- and gender-matched non-OUD controls during a simple visual object recognition Go/No-Go task. Overall, women had significantly slower reaction times (RTs) than men. In addition, EEG N200 and P300 event-related potential (ERP) amplitudes for non-OUD controls were significantly larger for men, while their latencies were significantly shorter than for women. However, while N200 and P300 amplitudes were not significantly affected by OUD for either men or women in this task, latencies were also affected differentially in men vs. women with OUD. Accordingly, for both N200 and P300, male OUD participants exhibited longer latencies while female OUD participants exhibited shorter ones than in non-OUD controls. Additionally, robust oscillations were found in all participants during a feedback message associated with performance in the task. Although alpha and beta power during the feedback message were significantly greater for men than women overall, both alpha and beta oscillations exhibited significantly lower power in all participants with OUD. Taken together, these findings suggest important gender by OUD differences in cognitive processing and reflection of performance in this simple visual task.

Risk factors for opioid addiction in chronic non-cancer pain

Opioids are very effective pain medications, but they are not without complications. Its use in chronic cancer pain is clearly established, but not in chronic non-cancer pain. Opioid use has increased in recent years, but at the same time, it has been accompanied by an increase in side effects and related complications, including abuse, abuse and opioid addiction. If we look in the literature on the subject there is a global concern to make an adequate therapy with risk reduction, but the samples studied make it difficult to extrapolate results to the general population and even more so if we take into account factors such as psychiatric comorbidity. This leads us to consider the need to study our own population, its characteristics and see how it is being treated, to refine as much as possible on an appropriate prescription. The authors have carried out a cross-sectional study on patients with non-cancer chronic pain referred to psychiatry and the presence of opioid use disorder. We found risk factors related to the biopsychosocial characteristics of the patients and the characteristics of pain and its treatment. Knowing the risk factors, we can avoid yatrogeny, implement primary and secondary prevention and, ultimately, improve the quality of patient care.

Gender differences in physical morbidity in opioid agonist treatment patients: population-based cohort studies from the Czech Republic and Norway

BACKGROUND

Physical diseases represent a significant burden for opioid agonist treatment (OAT) patients. This study described physical morbidity in two national cohorts of OAT patients focusing on gender differences.

METHODS

This population-based cohort study linking multiple health registers investigated physical diseases (ICD-10) in patients receiving OAT in the Czech Republic (N = 4,280) and Norway (N = 11,389) during 2010-2019. Gender-stratified analysis was performed.

RESULTS

Overall, we found a large burden of physical morbidity across gender groups in OAT patients. In the Czech Republic and Norway, women in OAT had a significantly higher prevalence of physical diseases across most diagnostic chapters, notably genitourinary diseases and neoplasms. Injuries/external causes and infectious/parasitic diseases were among the most common diseases in both women and men. Viral hepatitis accounted for over half of infectious morbidity in women and men in both cohorts.

CONCLUSIONS

Our findings support the need for early screening, detection, and treatment of diseases and conditions across organ systems and the integration of health promotion activities to reduce physical morbidity in OAT patients. The gender differences underline the need for a tailored approach to address specific medical conditions.

Effects of sex and estrous cycle on intravenous oxycodone self-administration and the reinstatement of oxycodone-seeking behavior in rats

Introduction

The increasing misuse of both prescription and illicit opioids has culminated in a national healthcare crisis in the United States. Oxycodone is among the most widely prescribed and misused opioid pain relievers and has been associated with a high risk for transition to compulsive opioid use. Here, we sought to examine potential sex differences and estrous cycle-dependent effects on the reinforcing efficacy of oxycodone, as well as on stress-induced or cue-induced oxycodone-seeking behavior, using intravenous (IV) oxycodone self-administration and reinstatement procedures.

Methods

In experiment 1, adult male and female Long-Evans rats were trained to self-administer 0.03 mg/kg/inf oxycodone according to a fixed-ratio 1 schedule of reinforcement in daily 2-h sessions, and a dose-response function was subsequently determined (0.003-0.03 mg/kg/inf). In experiment 2, a separate group of adult male and female Long-Evans rats were trained to self-administer 0.03 mg/kg/inf oxycodone for 8 sessions, followed by 0.01 mg/kg/inf oxycodone for 10 sessions. Responding was then extinguished, followed by sequential footshock-induced and cue-induced reinstatement tests.

Results

In the dose-response experiment, oxycodone produced a typical inverted U-shape function with 0.01 mg/kg/inf representing the maximally effective dose in both sexes. No sex differences were detected in the reinforcing efficacy of oxycodone. In the second experiment, the reinforcing effects of 0.01-0.03 mg//kg/inf oxycodone were significantly attenuated in females during proestrus/estrus as compared to metestrus/diestrus phases of the estrous cycle. Neither males nor females displayed significant footshock-induced reinstatement of oxycodone seeking, but both sexes exhibited significant cue-induced reinstatement of oxycodone seeking at magnitudes that did not differ either by sex or by estrous cycle phase.

Discussion

These results confirm and extend previous work suggesting that sex does not robustly influence the primary reinforcing effects of oxycodone nor the reinstatement of oxycodone-seeking behavior. However, our findings reveal for the first time that the reinforcing efficacy of IV oxycodone varies across the estrous cycle in female rats.

Effects of sex and estrous cycle on intravenous oxycodone self-administration and the reinstatement of oxycodone-seeking behavior in rats

The increasing misuse of both prescription and illicit opioids has culminated in a national healthcare crisis in the United States. Oxycodone is among the most widely prescribed and misused opioid pain relievers and has been associated with a high risk for transition to compulsive opioid use. Here, we sought to examine potential sex differences and estrous cycle-dependent effects on the reinforcing efficacy of oxycodone, as well as on stress-induced or cue-induced oxycodone-seeking behavior, using intravenous (IV) oxycodone self-administration and reinstatement procedures. In experiment 1, adult male and female Long-Evans rats were trained to self-administer 0.03 mg/kg/inf oxycodone according to a fixed-ratio 1 schedule of reinforcement in daily 2-hr sessions, and a dose-response function was subsequently determined (0.003-0.03 mg/kg/inf). In experiment 2, a separate group of adult male and female Long-Evans rats were trained to self-administer 0.03 mg/kg/inf oxycodone for 8 sessions, followed by 0.01 mg/kg/inf oxycodone for 10 sessions. Responding was then extinguished, followed by sequential footshock-induced and cue-induced reinstatement tests. In the dose-response experiment, oxycodone produced a typical inverted U-shape function with 0.01 mg/kg/inf representing the maximally effective dose in both sexes. No sex differences were detected in the reinforcing efficacy of oxycodone. In the second experiment, the reinforcing effects of 0.01-0.03 mg//kg/inf oxycodone were significantly attenuated in females during proestrus/estrus as compared to metestrus/diestrus phases of the estrous cycle. Neither males nor females displayed significant footshock-induced reinstatement of oxycodone seeking, but both sexes exhibited significant cue-induced reinstatement of oxycodone seeking at magnitudes that did not differ either by sex or by estrous cycle phase. These results confirm and extend previous work suggesting that sex does not robustly influence the primary reinforcing effects of oxycodone nor the reinstatement of oxycodone-seeking behavior. However, our findings reveal for the first time that the reinforcing efficacy of IV oxycodone varies across the estrous cycle in female rats.

Association of receiving opioid medication-assisted treatment with sexual identity and mental health/substance use disorder symptoms in a nationally representative sample of adults

Background

Although the literature suggests that medication-assisted treatment (MAT) is an effective treatment for opioid use disorder, limited studies have assessed the prevalence or the association between MAT use and sexual identity, mental health, or substance use disorder among a nationally representative sample. We assessed the prevalence and association of opioid MAT use between sexual identity, depressive disorder symptoms, alcohol use dependence, and marijuana use dependence in the United States.

Methods

We used the 2019 National Survey on Drug Use and Health public-use data on adults aged 18-64 years (N = 38,841) to conduct a weighted multivariable logistic regression analysis.

Results

A total of 4.80% and 2.32% of the population identified as bisexual and lesbian/gay, respectively. About 0.31% (612,750 people) of the population reported receiving opioid MAT, 3.73% had alcohol use dependence, 1.42% had marijuana use dependence, and 9.13% had major depressive episode (MDE) symptoms. Of those who had received opioid MAT, 0.57% were bisexuals and 1.07% were lesbians/gays, 0.65% were people with alcohol use dependence, 2.32% with marijuana use dependence, and 1.59% with MDE symptoms. Lesbian/gay individuals were more likely to receive opioid MAT (AOR = 3.43, 95% CI = 1.42, 8.25) compared to heterosexual individuals. The odds were higher for people with marijuana use dependence (AOR = 3.44, 95% CI = 1.47, 8.06) and MDE symptoms (AOR = 5.22, 95% CI = 3.46, 7.89) than their counterparts.

Conclusions

In this study, sexual minorities, people with MDE symptoms, and those dependent on marijuana use were more likely to receive opioid MAT, suggesting the need to investigate further opioid use disorder symptoms and their risk factors among these populations.

Orbitofrontal cortex microRNAs support long-lasting heroin seeking behavior in male rats

Recovery from opioid use disorder (OUD) and maintenance of abstinence from opioid use is hampered by perseverant drug cravings that may persist for months after cessation of drug use. Drug cravings can intensify during the abstinence period, a phenomenon referred to as the 'incubation of craving' that has been well-described in preclinical studies. We previously reported that animals that self-administered heroin at a dosage of 0.075 mg/kg/infusion (HH) paired with discrete drug cues displayed robust incubation of heroin craving behavior after 21 days (D) of forced abstinence, an effect that was not observed with a lower dosage (0.03 mg/kg/infusion; HL). Here, we sought to elucidate molecular mechanisms underlying long-term heroin seeking behavior by profiling microRNA (miRNA) pathways in the orbitofrontal cortex (OFC), a brain region that modulates incubation of heroin seeking. miRNAs are small noncoding RNAs with long half-lives that have emerged as critical regulators of drug seeking behavior but their expression in the OFC has not been examined in any drug exposure paradigm. We employed next generation sequencing to detect OFC miRNAs differentially expressed after 21D of forced abstinence between HH and HL animals, and proteomics analysis to elucidate miRNA-dependent translational neuroadaptations. We identified 55 OFC miRNAs associated with incubation of heroin craving, including miR-485-5p, which was significantly downregulated following 21D forced abstinence in HH but not HL animals. We bidirectionally manipulated miR-485-5p in the OFC to demonstrate that miR-485-5p can regulate long-lasting heroin seeking behavior after extended forced abstinence. Proteomics analysis identified 45 proteins selectively regulated in the OFC of HH but not HL animals that underwent 21D forced abstinence, of which 7 were putative miR-485-5p target genes. Thus, the miR-485-5p pathway is dysregulated in animals with a phenotype of persistent heroin craving behavior and OFC miR-485-5p pathways may function to support long-lasting heroin seeking.

Substance Misuse Themes Among Women Living in Transitional Housing: Effects on Children, Intimate Partner Relationships, and Social Relationships

ABSTRACT

Traditional substance misuse treatments have not always taken women or marginalized populations into consideration. A holistic approach that addresses how drugs may be used to cope with trauma caused by violence, poverty, and neglect as well as employment of engagement strategies that connect populations with culturally relevant support systems are key, especially in treating African American women. As substance misuse rates rise among African American women, characterizing how this may influence or be influenced by relationships (such as with children, intimate partners, and social relations) is especially important in the context of effective treatment. The purpose of this qualitative study was to examine the themes surrounding substance misuse and close relationships among women previously enrolled in a transitional housing treatment program grounded in social support. Many women discussed how the program itself was an impetus in addressing not only their own substance use but also intergenerational substance use within their families. Women also noted how relationships with their children were vastly different pretreatment compared with during and after treatment, specifically emphasizing a positive improvement. Regarding intimate relationships, African American women learned to establish assertiveness and navigate healthier social relationships, all while sustaining drug abstinence. It is important to acknowledge the role of the healthcare professional in ensuring effective and culturally relevant treatment for African American women; nursing curricula should include evidence-based practice education and training on mental health and substance misuse specific to marginalized communities to more deeply understand the complex intersections of substance misuse, poverty, and social relationships in the lives of women.

Effects of buprenorphine on opioid craving in comparison to other medications for opioid use disorder: A systematic review of randomized controlled trials

BACKGROUND

Craving is a distressing symptom of opioid use disorder (OUD) that can be alleviated with medications for OUD (MOUD). Buprenorphine is an effective MOUD that may suppress craving; however, treatment discontinuation and resumed opioid use is common during the early phases of treatment. More information on the craving response through the high-risk period of initiating buprenorphine may provide meaningful information on how to better target craving, which in turn may enhance outcomes. This systematic review investigated buprenorphine doses and formulations on craving during the induction and maintenance phases of treatment, and for context also compared the craving response to other MOUD (i.e., methadone, extended-release naltrexone [XR-NTX]).

METHODS

PubMed, PsycInfo, Embase, and Cochrane Central databases were searched for randomized trials of buprenorphine versus placebo, various buprenorphine formulations/doses, or other MOUD that included a measure of opioid craving.

RESULTS

A total of 10 studies were selected for inclusion. Buprenorphine and buprenorphine/naloxone (BUP/NAL) were each associated with lower craving than placebo over time. Craving was greater among those prescribed lower versus higher buprenorphine doses. In comparison to other MOUD, buprenorphine or BUP/NAL was linked to greater craving than methadone in 3 of the 6 studies. BUP/NAL was associated with greater reported craving than XR-NTX.

DISCUSSION

Craving is reduced over time with buprenorphine and BUP/NAL, although other MOUD may provide greater reductions in craving. Although there is currently considerable variability in the measurement of craving, it may be a valuable concept to address with individuals receiving MOUD, especially early in treatment.

Effects of neonatal fentanyl on late adolescent opioid-mediated behavior

Introduction

Because of the steady increase in the use of synthetic opioids in women of childbearing age, a large number of children are at risk of exposure to these drugs prenatally or postnatally through breast milk. While there is older literature looking at the effects of morphine and heroin, there are relatively few studies looking at the long-term effects of high-potency synthetic opioid compounds like fentanyl. Thus, in the present study, we assessed whether brief exposure to fentanyl in male and female rat pups during a period roughly equivalent to the third trimester of CNS development altered adolescent oral fentanyl self-administration and opioid-mediated thermal antinociception.

Methods

We treated the rats with fentanyl (0, 10, or 100 μg/kg sc) from postnatal day (PD) 4 to PD 9. The fentanyl was administered daily in two injections given 6 h apart. After the last injection on PD 9, the rat pups were left alone until either PD 40 where they began fentanyl self-administration training or PD 60 where they were tested for morphine- (0, 1.25, 2.5, 5, or 10 mg/kg) or U50,488- (0, 2.5, 5, 10, or 20 mg/kg) induced thermal antinociception.

Results

In the self-administration study, we found that female rats had more active nose pokes than male rats when receiving a fentanyl reward but not sucrose alone solution. Early neonatal fentanyl exposure did not significantly alter fentanyl intake or nose-poke response. In contrast, early fentanyl exposure did alter thermal antinociception in both male and female rats. Specifically, fentanyl (10 μg/kg) pre-treatment increased baseline paw-lick latencies, and the higher dose of fentanyl (100 μg/kg) reduced morphine-induced paw-lick latencies. Fentanyl pre-treatment did not alter U50,488-mediated thermal antinociception.

Conclusions

Although our exposure model is not reflective of typical human fentanyl use during pregnancy, our study does illustrate that even brief exposure to fentanyl during early development can have long-lasting effects on mu-opioid-mediated behavior. Moreover, our data suggest that females may be more susceptible to fentanyl abuse than males.

Sex-differences in anxiety, neuroinflammatory markers, and enhanced fear learning following chronic heroin withdrawal

Post-traumatic stress disorder (PTSD) and opioid use disorder (OUD) are comorbid in clinical populations. However, both pre-clinical and clinical studies of these co-occurring disorders have disproportionately represented male subjects, limiting the applicability of these findings. Our previous work has identified chronic escalating heroin administration and withdrawal can produce enhanced fear learning. This behavior is associated with an increase in dorsal hippocampal (DH) interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and glial fibrillary acidic protein (GFAP) immunoreactivity. Further, we have shown that these increases in IL-1β and TNF-α are mechanistically necessary for the development of enhanced fear learning. Although these are exciting findings, this paradigm has only been studied in males. The current studies aim to examine sex differences in the behavioral and neuroimmune effects of chronic heroin withdrawal and future enhanced fear learning. In turn, we determined that chronic escalating heroin administration can produce withdrawal in female rats comparable to male rats. Subsequently, we examined the consequence of heroin withdrawal on future enhanced fear learning and IL-1β, TNF-α, and GFAP immunoreactivity. Strikingly, we identified sex differences in these neuroimmune measures, as chronic heroin administration and withdrawal does not produce enhanced fear learning or immunoreactivity changes in females. Moreover, we determined whether heroin withdrawal produces short-term and long-term anxiety behaviors in both female and males. Collectively, these novel experiments are the first to test whether heroin withdrawal can sensitize future fear learning, produce neurobiological changes, and cause short-term and long-term anxiety behaviors in female rats.

Severity of emergency department presentations due to acute drug toxicity in Europe: a longitudinal analysis over a 6-year period (2014-2019) stratified by sex

OBJECTIVE

To investigate whether the severity of acute recreation drug toxicity presentations to emergency departments (EDs) in Europe has changed in recent years and to uncover potential sex differences.

DESIGN

We analysed presentations to 36 EDs in 24 European countries relating to acute recreational drug toxicity, with separate analysis for presentations involving lone use of cannabis, cocaine, and heroin. As severity markers, we calculated rates of hospitalization, admission to ICU, intubation, and death by annual quarters between 2014 and 2019. Trends on severity over time were estimated by logistic regression. Differences between men and women were assessed by interaction. Sensitivity analysis was performed including only EDs that provided data for all 24 quarters. Analyses of intoxications taken altogether were adjusted by age and sex, while of lone intoxications being also adjusted by ethanol co-ingestion.

RESULTS

There were 43 633 presentations (median age = 31 years, interquartile range = 25-40 years, men = 76.5%) resulting in 10 344 hospitalizations (23.9%), 2568 ICU admissions (5.9%), 1391 intubations (3.2%), and 171 deaths (0.39%). Hospitalization, ICU admission and death did not differ by sex, but intubation was more frequent in men (3.4% vs. 2.3%, P < 0.001). No significant changes in the severity of drug intoxications over time were found when considered altogether, neither for lone cannabis (n = 4264) nor cocaine (n = 3562). Conversely, significant increases in hospitalization [odds ratios (OR) = 1.023, 95% confidence interval (CI) = 1.004-1.041], ICU admission (OR = 1.080, 95% CI = 1.042-1.118) and in intubation (OR = 1.049, 95% CI = 1.001-1.099) were detected for lone heroin presentations (n = 1997). Sensitivity analysis (32 245 presentations, 14 EDs, 9 countries) confirmed the overall absence of changes in severity markers (except for death rate, which significantly decreased by quarter: OR = 0.968, 95% CI = 0.943-0.994). Additionally, it suggested an increased risk over time of intubation for cocaine (OR = 1.068, 95% CI = 1.009-1.130) and confirmed the increased risk of ICU admission for heroin (OR = 1.058, 95% CI = 1.013-1.105). Changes in severity over time did not differ according to sex in the main analysis of the whole cohort, while a significantly higher decrease in risk of death in men was found in the sensitivity analysis (OR = 0.894, 95% CI = 0.825-969 vs. OR = 0.949, 95% CI = 0.860-1.048; P interaction = 0.042).

CONCLUSIONS

The severity of presentations to European EDs remained mainly unchanged during 2014-2019, but the risk of death may have decreased. Conversely, intubation in lone cocaine and ICU admission in lone heroin intoxications have increased. Although men and women exhibited a similar pattern over the period for the majority of comparisons, our data suggest that women exhibited a smaller decrease of the overall risk of death.

Sex differences in the neuroadaptations associated with incubated cocaine-craving: A focus on the dorsomedial prefrontal cortex

Introduction

Women have a shorter course from initial cocaine use to meeting the criteria for cocaine use disorder as compared to men. Preclinical findings similarly indicate that females develop key features of an addiction-like phenotype faster than males, including an enhanced motivation for cocaine and compulsive use, indicating that this phenomenon is biologically based. The goals of this study were to determine whether cocaine-craving, another key feature of addiction, also develops sooner during withdrawal in females than males and to determine whether there are sex differences in the molecular mechanisms associated with its development focusing on markers known to mediate cocaine-craving in males (i.e., dorsomedial prefrontal cortex, dmPFC, expression of brain-derived neurotrophic factor exon-IV, Bdnf-IV, and NMDA receptor subunits, Grin2a, Grin2b, and Grin1).

Methods

Cocaine-craving was assessed following extended-access cocaine self-administration and 2, 7, or 14 days of withdrawal using an extinction/cue-induced reinstatement procedure. Tissue was obtained from the dmPFC immediately after reinstatement testing and gene expression changes were analyzed using real-time qPCR.

Results

In males, cocaine-craving (total extinction and cue-induced reinstatement responding) progressively increased from early to later withdrawal time-points whereas in females, cocaine-craving was already elevated during early withdrawal (after 2 days) and did not further increase at later withdrawal time-points. Levels of cocaine-craving, however, were similar between the sexes. Gene expression changes differed markedly between the sexes such that males showed the expected relapse- and withdrawal-associated changes in Bdnf-IV, Grin2a, Grin2b, and Grin1 expression, but females only showed a modest increase Grin1 expression at the intermediate withdrawal timepoint.

Discussion

These findings indicate that cocaine-craving is similarly expressed in males and females although the time-course for its incubation appears to be accelerated in females; the molecular mechanisms also likely differ in females versus males.

Suvorexant, an FDA-approved dual orexin receptor antagonist, reduces oxycodone self-administration and conditioned reinstatement in male and female rats

Background: The Department of Health and Human Services reports that prescription pain reliever (e.g., oxycodone) misuse was initiated by 4,400 Americans each day in 2019. Amid the opioid crisis, effective strategies to prevent and treat prescription opioid use disorder (OUD) are pressing. In preclinical models, the orexin system is recruited by drugs of abuse, and blockade of orexin receptors (OX receptors) prevents drug-seeking behavior. The present study sought to determine whether repurposing suvorexant (SUV), a dual OX receptor antagonist marketed for the treatment of insomnia, can treat two features of prescription OUD: exaggerated consumption and relapse. Methods: Male and female Wistar rats were trained to self-administer oxycodone (0.15 mg/kg, i. v., 8 h/day) in the presence of a contextual/discriminative stimulus (S^D) and the ability of SUV (0-20 mg/kg, p. o.) to decrease oxycodone self-administration was tested. After self-administration testing, the rats underwent extinction training, after which we tested the ability of SUV (0 and 20 mg/kg, p. o.) to prevent reinstatement of oxycodone seeking elicited by the S^D. Results: The rats acquired oxycodone self-administration and intake was correlated with the signs of physical opioid withdrawal. Additionally, females self-administered approximately twice as much oxycodone as males. Although SUV had no overall effect on oxycodone self-administration, scrutiny of the 8-h time-course revealed that 20 mg/kg SUV decreased oxycodone self-administration during the first hour in males and females. The oxycodone S^D elicited strong reinstatement of oxycodone-seeking behavior that was significantly more robust in females. Suvorexant blocked oxycodone seeking in males and reduced it in females. Conclusions: These results support the targeting of OX receptors for the treatment for prescription OUD and repurposing SUV as pharmacotherapy for OUD.

Sex Differences in Comorbid Mental and Substance Use Disorders Among Primary Care Patients With Opioid Use Disorder

OBJECTIVE

The authors sought to characterize the 3-year prevalence of mental disorders and nonnicotine substance use disorders among male and female primary care patients with documented opioid use disorder across large U.S. health systems.

METHODS

This retrospective study used 2014-2016 data from patients ages ≥16 years in six health systems. Diagnoses were obtained from electronic health records or claims data; opioid use disorder treatment with buprenorphine or injectable extended-release naltrexone was determined through prescription and procedure data. Adjusted prevalence of comorbid conditions among patients with opioid use disorder (with or without treatment), stratified by sex, was estimated by fitting logistic regression models for each condition and applying marginal standardization.

RESULTS

Females (53.2%, N=7,431) and males (46.8%, N=6,548) had a similar prevalence of opioid use disorder. Comorbid mental disorders among those with opioid use disorder were more prevalent among females (86.4% vs. 74.3%, respectively), whereas comorbid other substance use disorders (excluding nicotine) were more common among males (51.9% vs. 60.9%, respectively). These differences held for those receiving medication treatment for opioid use disorder, with mental disorders being more common among treated females (83% vs. 71%) and other substance use disorders more common among treated males (68% vs. 63%). Among patients with a single mental health condition comorbid with opioid use disorder, females were less likely than males to receive medication treatment for opioid use disorder (15% vs. 20%, respectively).

CONCLUSIONS

The high rate of comorbid conditions among patients with opioid use disorder indicates a strong need to supply primary care providers with adequate resources for integrated opioid use disorder treatment.

Sex differences in the medial prefrontal cortical glutamate system

BACKGROUND

Dysregulation in the prefrontal cortex underlies a variety of psychiatric illnesses, including substance use disorder, depression, and anxiety. Despite the established sex differences in prevalence and presentation of these illnesses, the neural mechanisms driving these differences are largely unexplored. Here, we investigate potential sex differences in glutamatergic transmission within the medial prefrontal cortex (mPFC). The goal of these experiments was to determine if there are baseline sex differences in transmission within this region that may underlie sex differences in diseases that involve dysregulation in the prefrontal cortex.

METHODS

Adult male and female C57Bl/6J mice were used for all experiments. Mice were killed and bilateral tissue samples were taken from the medial prefrontal cortex for western blotting. Both synaptosomal and total GluA1 and GluA2 levels were measured. In a second set of experiments, mice were killed and ex vivo slice electrophysiology was performed on prepared tissue from the medial prefrontal cortex. Spontaneous excitatory postsynaptic currents and rectification indices were measured.

RESULTS

Females exhibit higher levels of synaptosomal GluA1 and GluA2 in the mPFC compared to males. Despite similar trends, no statistically significant differences are seen in total levels of GluA1 and GluA2. Females also exhibit both a higher amplitude and higher frequency of spontaneous excitatory postsynaptic currents and greater inward rectification in the mPFC compared to males.

CONCLUSIONS

Overall, we conclude that there are sex differences in glutamatergic transmission in the mPFC. Our data suggest that females have higher levels of glutamatergic transmission in this region. This provides evidence that the development of sex-specific pharmacotherapies for various psychiatric diseases is important to create more effective treatments.

The Impact of Individual Counseling on Treatment for Opioid Use

ABSTRACT

In 2018, more than 67,000 people died because of drug overdoses, and of that number, approximately 69.5% involved an opioid, making it a leading cause of death in the United States. Additionally concerning is that 40 states have reported increased overdose deaths and opioid-related deaths since the start of the COVID-19 global pandemic. Presently, many insurance companies and healthcare providers require patients to receive counseling during medication treatment for opioid use disorder (OUD), despite the lack of evidence that it is necessary for all patients. To inform policy and improve quality of treatment, this nonexperimental, correlational study examined the relationship between individual counseling status and treatment outcomes in patients receiving medication treatment for OUD. Treatment outcome variables (treatment utilization, medication use, and opioid use) were extracted from the electronic health records of 669 adults who received treatment between January 2016 and January 2018. Study findings suggest women in our sample were more likely to test positive for benzodiazepines (t = -4.3, p < .001) and amphetamines (t = -4.4, p < .001), whereas men used alcohol at higher rates than women (t = 2.2, p = .026). In addition, women were more likely to report having experienced Post-Traumatic Stress Disorder/trauma (χ2 = 16.5, p < .001) and anxiety (χ2 = 9.4, p = .002). Regression analyses revealed concurrent counseling was unrelated to medication utilization and ongoing opioid use. Patients who had prior counseling utilized buprenorphine more frequently (β = 0.13, p < .001) and used opioids less often (β = -0.14, p < .001); however, both relationships were weak. These data do not provide evidence that counseling during OUD outpatient has a significant impact on treatment outcomes. These findings provide further evidence that barriers to medication treatment such as mandatory counseling can and should be removed.

Gender differences among persons entering medication treatment for opioid use disorder in the community

BACKGROUND AND OBJECTIVES

We evaluated gender differences among persons initiating medications for opioid use disorder (MOUD).

METHODS

Analyses of baseline assessments for a study evaluating the impact of MOUD on outcomes included: demographics, DSM-5 diagnoses, depression severity, quality of life (QoL), and medication history (N = 125).

RESULTS

When compared to men, women had a greater prevalence of generalized anxiety and posttraumatic stress disorders; and worse psychological QoL. Women were less likely to be prescribed psychiatric medications.

DISCUSSION AND CONCLUSIONS

Women may benefit from tailored multidisciplinary programs with MOUD.

SCIENTIFIC SIGNIFICANCE

This study identified that women with OUD seeking MOUD in the community had greater sedative hypnotic nonprescribed medication use and psychiatric comorbidity than men, all of which can contribute to poorer retention on MOUD and higher risk of morbidity and mortality. Thus, concurrent psychiatric disorder screening and treatment integrated with MOUD may improve retention on MOUD, opioid relapse and overdose for women.

Unique and joint associations of polygenic risk for major depression and opioid use disorder with endogenous opioid system function

Major depressive disorder (MDD) and opioid use disorder (OUD) are common, potentially fatal, polygenic disorders that are moderately heritable and often co-occur. We examined the unique and shared associations of polygenic risk scores (PRS) for these disorders with µ-opioid receptor (MOR) concentration and endogenous opioid response during a stressful stimulus. Participants were 144 healthy European-ancestry (EA) subjects (88 females) who underwent MOR quantification scans with [11C]carfentanil and PET and provided DNA for genotyping. MOR non-displaceable binding potential (BPND) was measured in 5 regions of interest (ROIs) related to mood and addiction. We examined associations of PRS both at baseline and following opioid release calculated as the ratio of baseline and stress-challenge scans, first in the entire sample and then separately by sex. MOR availability at baseline was positively associated with MDD PRS in the amygdala and ventral pallidum. MDD and OUD PRS were significantly associated with stress-induced opioid system activation in multiple ROIs, accounting for up to 14.5% and 5.4%, respectively, of the variance in regional activation. The associations were most robust among females, where combined they accounted for up to 25.0% of the variance among the ROIs. We conclude that there is a pathophysiologic link between polygenic risk for MDD and OUD and opioid system activity, as evidenced by PRS with unique and overlapping regional associations with this neurotransmitter system. This link could help to explain the high rate of comorbidity of MDD and OUD and suggests that opioid-modulating interventions could be useful in treating MDD and OUD, both individually and jointly.

Sex differences in the impact of pain, morphine administration and morphine withdrawal on quality of life in rats

The disruptive effects of pain on quality of life are greater in men than in women, but the disruptive effects of opioid administration and withdrawal tend to be greater in women. These sex differences in pain, acute opioid effects, and opioid withdrawal tend to be opposite to sex differences reported in laboratory rats. We hypothesized that sex differences in humans and rats would more closely align if animal research measured quality of life as opposed to traditional evoked behaviors of pain (e.g., nociceptive reflexes) and opioid withdrawal (e.g., wet dog shakes). The present study assessed quality of life in adult female and male rats by measuring voluntary wheel running in the rat's home cage. Hindpaw inflammation induced by administration of Complete Freund's Adjuvant (CFA) into the right hindpaw caused a greater depression of wheel running in male compared to female rats. Twice daily injections of high morphine doses (5-20 mg/kg) and the subsequent morphine withdrawal caused a greater depression of wheel running in female compared to male rats. These sex differences are consistent with human data that shows the impact of pain on quality of life is greater in men than women, but the negative effects of opioid administration and withdrawal are greater in women. The present data indicate that the clinical significance of animal research would be enhanced by shifting the endpoint from pain and opioid evoked behaviors to measures of quality of life such as voluntary wheel running.

Shared Decision-Making Tool for Opioid Prescribing After Ambulatory Orthopedic Surgery in Veterans: A Randomized Controlled Clinical Trial

Purpose

We examined whether an educational, shared-decision-making tool designed to empower patients, individualize pain management, and maximize use of nonopioid, over-the-counter analgesics reduces opioid use and waste while maintaining adequate pain relief.

Methods

We developed an educational, shared-decision-making tool regarding postoperative pain medication for outpatient hand surgery. Patients randomized to groups with and without the tool were surveyed for 4 weeks after surgery. Survey variables included Patient-Reported Outcomes Measurement Information System pain intensity and pain interference scores, as well as the number of oxycodone or over-the-counter pills taken. Results were compared using chi-squared, Wilcoxon rank-sum, and Welch’s t tests.

Results

Fifty-three patients participated: 25 in the shared-tool group and 28 in the no-tool group. The mean age was 60 years, with more women in the no-tool group than the shared-tool group (n =17 versus 11, respectively). The shared-tool group averaged 6.4 prescribed oxycodone pills, versus 10 for the no-tool group (P < .01). The median numbers of oxycodone pills taken the first week after surgery were 2 (interquartile range, 6) for the shared-tool group and 3 (interquartile range, 6) for the no-tool group (P = .97). Patient-reported outcome measures for pain intensity and pain interference were not significantly different for weeks 1, 3, and 4 after surgery. Pain interference was significantly lower in week 2 in the shared-tool group (difference, −4.4; 95% confidence interval, −8.57 to −0.30; P = .04).

Conclusions

The shared-tool group had equivalent or better pain control and were prescribed a lower number of opioid pain pills than the no-tool group. Both groups used nonopioid medications, with no difference in the types of over-the-counter medications used. Shared decision-making strategies could be applied to other outpatient orthopedic surgical settings, and may reduce the amount of opioids prescribed without compromising pain control.

Type of study/level of evidence

Therapeutic II.

Sex, gender, and the opioid epidemic: Crucial implications for acute care

Introduction

The opioid epidemic continues to escalate in the United States, exacerbated significantly by the COVID-19 pandemic. Necessary steps in acute care medicine to expand efforts to combat this epidemic involve increased emergency department engagement of patients with opioid use disorder (OUD) and an incorporation of evolving sex- and gender-based factors that affect this disease presentation and management course.

Methods & Aims

An ever-increasing amount of peer-reviewed, evidence-based literature has shed light on the important biologic and sociocultural variables, specifically sex and gender, which impact OUD trajectory and outcomes. As a collaborative effort of the Sex and Gender in Emergency Medicine (SGEM) Interest Group, a community within the Society for Academic Emergency Medicine (SAEM), we sought to consider, review, and summarize clinically pertinent information as a comprehensive introduction to this topic for the emergency medicine (EM) clinician and educator.

Results

A selected overview of current evidence-based data and publications, to include current epidemiologic trends, opioid-based physiology and pathophysiology, as well as opioid use disorder management and outcomes, through a sex- and gender-based lens, was reviewed and included in this summary. Also discussed are implications and recommendations for EM educators seeking insight and resources for continuing, graduate, and/or undergraduate education on this topic.

Conclusion

Incorporation of emerging sex- and gender-specific scientific knowledge into clinical context represents a critical link to effective management of the OUD patient in the ED. Similarly, integration of this information into EM education represents an essential step for both sex- and gender-based medicine and opioid-specific training.

Sex-Related Differences in Pharmacological Response to CNS Drugs: A Narrative Review

In the last decades, both animal and human studies have neglected female subjects with the aim of evading a theorized intricacy of feminine hormonal status. However, clinical experience proves that pharmacological response may vary between the two sexes since pathophysiological dissimilarities between men and women significantly influence the pharmacokinetics and pharmacodynamics of drugs. Sex-related differences in central nervous system (CNS) medication are particularly challenging to assess due to the complexity of disease manifestation, drugs’ intricate mechanisms of action, and lack of trustworthy means of evaluating the clinical response to medication. Although many studies showed contrary results, it appears to be a general tendency towards a certain sex-related difference in each pharmacological class. Broadly, opioids seem to produce better analgesia in women especially when they are administered for a prolonged period of time. On the other hand, respiratory and gastrointestinal adverse drug reactions (ADRs) following morphine therapy are more prevalent among female patients. Regarding antidepressants, studies suggest that males might respond better to tricyclic antidepressants (TCAs), whereas females prefer selective serotonin reuptake inhibitors (SSRI), probably due to their tolerance to particular ADRs. In general, studies missed spotting any significant sex-related differences in the therapeutic effect of antiepileptic drugs (AED), but ADRs have sex variations in conjunction with sex hormones’ metabolism. On the subject of antipsychotic therapy, women appear to have a superior response to this pharmacological class, although there are also studies claiming the opposite. However, it seems that reported sex-related differences regarding ADRs are steadier: women are more at risk of developing various side effects, such as metabolic dysfunctions, cardiovascular disorders, and hyperprolactinemia. Taking all of the above into account, it seems that response to CNS drugs might be occasionally influenced by sex as a biological variable. Nonetheless, although for each pharmacological class, studies generally converge to a certain pattern, opposite outcomes are standing in the way of a clear consensus. Hence, the fact that so many studies are yielding conflicting results emphasizes once again the need to address sex-related differences in pharmacological response to drugs.

Health Care Utilization Patterns for Patients With a History of Substance Use Requiring OPAT

Background

Uninsured people who use drugs (PWUD) require extended parenteral antibiotic therapy when diagnosed with complex infections such as osteomyelitis. They are ineligible to enroll in our self-administered outpatient antimicrobial therapy (S-OPAT) program and instead sent to a skilled nursing facility (SNF). We aim to retrospectively assess clinical outcomes of PWUD discharged from our safety net hospital to complete OPAT in an SNF.

Methods

Using our hospital electronic medical record, PWUD discharged to an SNF for extended antibiotic therapy were identified for the study period, 1/1/17–4/30/18. Demographics, drug use, discharge diagnosis, antibiotic therapy, discharge disposition from SNF (AMA, early non-AMA, completed), 30-day emergency department (ED) utilization, and 30-day readmission were collected for the study cohort. ED utilization and 30-day readmission rates were analyzed by disposition group.

Results

While the majority of patients completed treatment (83), a sizeable number left AMA (26) or early non-AMA (20). Patients who left early, AMA or non-AMA, had increased rates of 30-day readmission or ED utilization (P=.01) and increased rates of 30-day readmission alone (P=.01), but not ED utilization alone (P=.43), compared with patients who completed treatment.

Conclusions

In our cohort, many PWUD discharged to an SNF to receive parenteral antibiotics did not complete treatment. These patients were observed to have increased health care utilization compared with patients completing therapy.

Acting with awareness moderates the association between lifetime exposure to interpersonal traumatic events and craving via trauma symptoms: a moderated indirect effects model

BACKGROUND

History of exposure to traumatic events (ETE) is common among women in substance use disorder (SUD) treatment and is related to craving. We examined whether ETE (i.e., emotional, physical, sexual abuse) in childhood, adulthood, or both is related to craving via trauma symptoms and how trait mindfulness might attenuate this association.

METHODS

Baseline data from a larger randomized clinical trial of a mindfulness-based intervention for women (N = 245) in SUD treatment were used. Inclusion criteria were: 18-65 years of age, SUD diagnosis, English fluency, no cognitive impairment, and willingness to be audio recorded and provide consent. Demographics and validated measures of ETE, posttraumatic stress symptoms, trait mindfulness, and substance use craving were collected via in-person interviews. Descriptive statistics, correlational analysis, and relative direct, indirect, and conditional indirect effects models were run.

RESULTS

Most participants identified as Hispanic (58.5%), had at least a high school education (52.2%), with a mean age of 32.2. Women reported ETE in childhood only (20.4%), adulthood only (17.5%), both childhood and adulthood (50.0%), and never (11.4%). Compared to women with ETE in both childhood and adulthood, those with exposure in adulthood only (β = -.10, 95% CI = -.20, -.02) or no exposure (β = -.11, 95% CI = -.23, -.03; [∆R2= .347, F(8, 245) = 15.7, p < .001) had lower craving via lower trauma symptomatology but no difference when compared to those with ETE only in childhood. Acting with awareness moderated this indirect effect (∆R2 = .04, F(3, 245) = 4.66, p = .004. At low levels of awareness, women with ETE during both childhood and adulthood reported higher craving via trauma symptomatology than women with no exposure or only adulthood exposure.

CONCLUSIONS

Low levels of acting with awareness may worsen trauma symptoms after ETE, which in turn may lead to more craving for women in substance use treatment. Despite a small moderating effect size, acting with awareness may have clinical significance due to the prevalence of trauma symptoms among women in SUD treatment.

Sex- and Dose-Dependent Differences in the Development of an Addiction-Like Phenotype Following Extended-Access Fentanyl Self-Administration

Opioid use disorder (OUD) is a major epidemic in the United States, and fentanyl is a major culprit. The National Institute on Drug Abuse has highlighted an urgent need for research on the risks and outcomes of OUD with fentanyl; a better understanding of sex/gender differences is also critically needed given that the opioid epidemic has been particularly impactful on women. In response to this need, we developed a rat model of OUD with fentanyl and showed that sex impacts relapse vulnerability following extended-access self-administration under a low fentanyl dose. Here, our goal was to determine sex differences across a broad dose range, including high doses expected to maximize the expression of addiction-like features (e.g., vulnerability to relapse and physical dependence). Male and female rats were assigned to self-administer one of four fentanyl doses (0.25, 0.75, 1.5, and 3.0 µg/kg/infusion), and once they acquired, they were given extended (24-h/day), intermittent access (2, 5 min trials/h, fixed-ratio 1) to fentanyl for 10 days. Physical dependence (spontaneous weight loss) was assessed during early withdrawal, and relapse vulnerability was assessed on withdrawal day 15 using an extinction/cue-induced reinstatement procedure. Despite markedly higher intake in the high- versus low-dose groups, each group responded similarly during relapse testing (extinction and cue-induced reinstatement). However, number of infusions, or frequency of use, during extended access was predictive of later vulnerability to relapse, whereas total intake impacted physical dependence given that weight loss only occurred following the discontinuation of fentanyl self-administration at the three highest doses. Females self-administered more fentanyl each day and within each binge (active trial), and had longer lasting weight loss during withdrawal than males. Relapse vulnerability was also higher in females than males and highest in females tested during estrus. These findings indicate that sex is an important risk factor for patterns and levels of fentanyl intake, relapse, and physical dependence, and while fentanyl intake predicts physical dependence, frequency of use predicts relapse.

Intimate partner violence as a predictor of substance use outcomes among women: A systematic review

Although the correlation between experience of intimate partner violence (IPV) and substance use among women has been well-established, there is no consensus on whether or how IPV impacts subsequent substance use behaviors or treatment success. To identify research gaps and implications for substance use treatment, we conducted a systematic review to identify and examine evidence on IPV as a predictor of subsequent substance use behaviors, substance use disorders (SUD), and treatment outcomes among women. We included studies published between 2010 and 2020 that assessed IPV experiences as a predictor of subsequent substance use behaviors (i.e., use initiation, increased use), SUD diagnosis, or treatment outcomes (i.e., incomplete treatment, relapse) among women. From 576 unique records, we included 10 studies (4 longitudinal, 4 cross-sectional, 2 qualitative). Alcohol use and alcohol use disorder were the most commonly studied outcomes (n = 6); findings were mixed regarding the significance of IPV being associated with subsequent alcohol outcomes. Three studies examined illicit drug use, finding that physical and sexual IPV predicted crack/cocaine use and were associated with SUD diagnoses. Four studies examining SUD treatment outcomes found IPV to impede treatment engagement and completion, increasing the likelihood of relapse. To our knowledge, this is the first systematic review of the literature on IPV as a predictor of substance use behaviors and treatment outcomes among women. Findings highlight the need for diverse SUD treatment modalities to incorporate IPV screening and referral to appropriate services into their programming to improve SUD management and the overall health and wellbeing of women.

Sex differences in opioid receptor mediated effects: Role of androgens

An abundance of data indicates there are sex differences in endogenous opioid peptides and opioid receptors, leading to functional differences in sensitivity to opioid receptor mediated behaviors between males and females. Many of these sex differences are mediated by the effects of gonadal hormones on the endogenous opioid system. Whereas much research has examined the role of ovarian hormones on opioid receptor mediated endpoints, comparatively less research has examined the role of androgens. This review describes what is currently known regarding the influence of androgens on opioid receptor mediated endpoints and how androgens may contribute to sex differences in these effects. The review also addresses the clinical implications of androgenic modulation of opioid receptor mediated behaviors and suggests future lines of research for preclinical and clinical investigators. We conclude that further investigation into androgenic modulation of opioid receptor mediated effects may lead to new options for addressing conditions such as chronic pain and substance use disorders.

Short communication: Relationship between social determinants and opioid use disorder treatment outcomes by gender

BACKGROUND

Social determinants of health (SDoH) influence health outcomes differentially across gender. Gender differences in SDoH have been identified at baseline in opioid use disorder (OUD) treatment studies, but less is known about how SDoH and gender intersect with OUD treatment trajectories. This study aims to identify social correlates of OUD treatment outcomes from five key areas of social determinants separately for men and women receiving buprenorphine for OUD.

METHODS

This is a secondary data analysis of a cross-sectional survey with medical record review conducted with patients recruited from an office based opioid treatment clinic. Participants completed surveys between July-September 2019. A 6-month prospective medical record review was conducted to determine treatment retention, substance use recurrence, and buprenorphine continuation. Chi square, T-tests, and Mann Whitney U tested differences in social factors and OUD outcomes by gender. Gender-stratified multivariable logistic and negative binomial regressions assessed predictors of OUD outcomes.

RESULTS

Among study participants (n = 142), women were significantly younger (p < 0.001), more likely to live in a safe neighborhood (p = 0.046), and less likely to be employed (p = 0.005) or have substance use recurrence during the study period (p = 0.033) than men. For women, employment (AOR=0.19, p = 0.031) and education (AOR=0.08, p = 0.040) were negatively associated with treatment retention. For men, no social factors were associated with OUD outcomes.

CONCLUSIONS

SDoH may impact OUD treatment outcomes differently by gender. Addressing MOUD stigma and implementing patient-centered care strategies may facilitate OUD treatment continuation among employed women in recovery. Gender-related social factors should be considered in OUD treatment research.

A systematic review of post-release programs for women exiting prison with substance-use disorders: assessing current programs and weighing the evidence

BACKGROUND

The rising rates of women in prison is a serious public health issue. Unlike men, women in prison are characterised by significant histories of trauma, poor mental health, and high rates of substance use disorders (SUDs). Recidivism rates of women have also increased exponentially in the last decade, with substance related offences being the most imprisoned offence worldwide. There is a lack of evidence of the effectiveness of post-release programs for women. The aim of this systematic review is to synthesise and evaluate the evidence on post-release programs for women exiting prison with SUDs.

METHODS

We searched eight scientific databases for empirical original research published in English with no date limitation. Studies with an objective to reduce recidivism for adult women (⩾18 years) with a SUD were included. Study quality was assessed using the revised Cochrane Risk of Bias tool for randomized trials (RoB2) and the Risk of Bias in Non-randomized Studies - of Interventions (ROBINS-I) tools.

RESULTS

Of the 1493 articles, twelve (n = 3799 women) met the inclusion criteria. Recidivism was significantly reduced in five (42%) programs and substance-use was significantly reduced in one (8.3%) program. Common attributes among programs that reduced recidivism were: transitional, gender-responsive programs; provision of individualised support; providing substance-related therapy, mental health and trauma treatment services. Methodological and reporting biases were common, which impacted our ability to synthesize results further. Recidivism was inconsistently measured across studies further impacting the ability to compare results across studies.

CONCLUSIONS

Recidivism is a problematic measure of program efficacy because it is inconsistently measured and deficit-focused, unrecognising of women's gains in the post-release period despite lack of tailored programs and significant health and social disadvantages. The current evidence suggests that women benefit from continuity of care from prison to the community, which incorporated gender-responsive programming and individualised case management that targeted co-morbid mental health and SUDs. Future program design should incorporate these attributes of successful programs identified in this review to better address the unique challenges that women with SUDs face when they transition back into the community.

Sex Differences in Opioid and Psychostimulant Craving and Relapse: A Critical Review

A widely held dogma in the preclinical addiction field is that females are more vulnerable than males to drug craving and relapse. Here, we first review clinical studies on sex differences in psychostimulant and opioid craving and relapse. Next, we review preclinical studies on sex differences in psychostimulant and opioid reinstatement of drug seeking after extinction of drug self-administration, and incubation of drug craving (time-dependent increase in drug seeking during abstinence). We also discuss ovarian hormones' role in relapse and craving in humans and animal models and speculate on brain mechanisms underlying their role in cocaine craving and relapse in rodent models. Finally, we discuss imaging studies on brain responses to cocaine cues and stress in men and women.The results of the clinical studies reviewed do not appear to support the notion that women are more vulnerable to psychostimulant and opioid craving and relapse. However, this conclusion is tentative because most of the studies reviewed were correlational, not sufficiently powered, and not a priori designed to detect sex differences. Additionally, imaging studies suggest sex differences in brain responses to cocaine cues and stress. The results of the preclinical studies reviewed provide evidence for sex differences in stress-induced reinstatement and incubation of cocaine craving but not cue- or cocaine-induced reinstatement of cocaine seeking. These sex differences are modulated in part by ovarian hormones. In contrast, the available data do not support the notion of sex differences in craving and relapse/reinstatement for methamphetamine or opioids in rodent models. SIGNIFICANCE STATEMENT: This systematic review summarizes clinical and preclinical studies on sex differences in psychostimulant and opioid craving and relapse. Results of the clinical studies reviewed do not appear to support the notion that women are more vulnerable to psychostimulant and opioid craving and relapse. Results of preclinical studies reviewed provide evidence for sex differences in reinstatement and incubation of cocaine seeking but not for reinstatement or incubation of methamphetamine or opioid seeking.

Sex Differences in Injection Drug Risk Behaviors Among Hospitalized Persons

OBJECTIVES

As opioid use increases, it remains important to assess factors that contribute to injection drug risk behaviors, as sharing needles and other drug use equipment contributes to the spread of human immunodeficiency virus and hepatitis C virus. Such risks may differ by sex and injecting with others. The current study examined factors that contribute to increased injection drug risk separately for men and women.

METHODS

People who inject drugs were recruited at an academic safety-net hospital that reported recent injection drug use. Two main injection outcomes were assessed: (1) human immunodeficiency virus drug risk behaviors as assessed by the Risk Assessment Battery and (2) the number of times participants injected drugs with a needle used by someone else. For each outcome, different models for women and men were conducted to detect differences by sex.

RESULTS

Both men and women were more likely to inject with a needle used by someone else if they used drugs within a sexual relationship (incidence rate ratio (IRR) = 14.61, P < 0.01; IRR = 7.17, P < 0.05). Being employed was associated with lower risk assessment battery scores among men, and lower mean rates of using a needle used by someone else among women (IRR = 0.22, P < 0.05). Women with post-traumatic stress disorder (PTSD) and men with higher depression scores had higher rates of injecting with a needle used by someone else.

CONCLUSIONS

People who inject drugs who are in intimate relationships report higher injection drug risk behaviors. We found benefits to employment among both men and women. Identifying factors associated with increased injection risk behaviors can be useful for creating interventions tailored by sex.

Gender Dynamics in Substance Use and Treatment: A Women's Focused Approach

Gender impacts substance use initiation, substance use disorder development, engagement with treatment, and harms related to drug and alcohol use. Using the biopsychosocial model of addiction, this review provides a broad summary of barriers and facilitators to addiction services among women. It also reviews substance use among pregnant and parenting women and approaches to care. Given the increasing rates of substance use among women, there is a need to implement and scale-up gender-responsive addiction programming and pursue advocacy at the policy level that addresses the root drivers of substance use inequities among women.