Underrepresentation of diverse populations and clinical characterization in opioid agonist treatment research: A systematic review of the neurocognitive effects of buprenorphine and methadone treatment

Gender disparities in neuropsychological assessment research in drug abuse populations: A systematic review

Objective: To systematically review the literature on the neurocognitive effects of drug use to determine if there are significant gender differences. Methods: In April 2023, we conducted a broad search in MEDLINE (via PubMed), PsycINFO, and Embase for original research studies that used objective neuropsychological assessment to evaluate neurocognition in persons with drug use. Data extraction was performed in a masked, duplicate fashion. Results: Our initial search returned 22,430 records, of which 273 articles were included in our analysis. We found significant underrepresentation of women as participants in the studies. Twenty-one percent of studies had exclusively male participants; when women were included, they averaged only 23% of the sample. Only 49 studies sufficiently documented an analysis of their results by gender; due to the heterogeneity in study characteristics, no conclusions about cognitive differences between women and men could be made. Conclusions: Women are significantly underrepresented in the research on cognition in drug use. Increased efforts to include more women participants and consistent analysis and reporting of data for potential gender differences will be required to close this gap in knowledge, which may lead to improved substance abuse treatment approaches for women.

Social and cognitive determinants of medications for opioid use disorder outcomes: A systematic review using a social determinants of health framework

Disparities exist in the engagement and success of individuals seeking medications for opioid use disorder (MOUD) treatment. Existing work suggests that individual-level factors such as cognitive functioning influence MOUD treatment, less is known about the role of environmental factors beyond the individual such as social determinants of health (SDOH). The aim of this systematic review was to summarize the literature of neuropsychological assessment in the context of MOUD treatment using an SDOH framework. We included peer-reviewed articles based in the United States and published in the English language that evaluated neuropsychological assessment on MOUD treatment outcomes. Three electronic databases were searched from January 2022 to September 2023 without restricting the date of publication for article inclusion. We identified 34 empirical articles that met inclusion criteria, the majority being nonrandomized clinical trials. Few studies examined differences in neuropsychological performance over time or in response to an adjunct intervention. Findings comparing cognitive functioning across MOUD and comparisons groups were mixed, as were findings from the studies that examined changes in cognitive functioning over time. Factors represented from the SDOH framework included educational attainment, premorbid intellectual functioning, and employment status. Neuropsychological domains and type of assessments varied, as did inclusion/exclusion and demographic characteristics. Existing literature is mixed on whether neuropsychological deficits in individuals with OUD are amenable to treatment, particularly among populations disproportionally disadvantaged by SDOH. More research is needed on the SDOH and other contextual factors that influence cognitive factors and MOUD treatment engagement and success.

Is there a disparity in medications for opioid use disorder based on race/ethnicity and gender? A systematic review and meta-analysis

BACKGROUND

Access to medications for opioid use disorder (MOUD) among racial/ethnic minorities is a growing concern.

OBJECTIVES

Inequalities in receiving MOUD among gender and racial/ethnic groups were examined in this systematic review.

METHODS

Studies were retrieved by searching various databases and reference lists of reviews and selected full texts. Adjusted Odds Ratios (AORs) comparing MOUDs among racial/ethnic minorities to Whites were extracted or estimated from their findings. Meta-analysis was performed using STATA 17.

RESULTS

After screening 2438 records, 19 studies were included in this review in two categories. The first category consists of 11 studies comparing receiving MOUD between different races/ethnicities and genders at the individual level. The meta-analysis regarding AORs comparing Blacks, Hispanics, Asians, Native Americans/Alaska-Natives, Hawaiians, and mixed-race patients with Whites were 0.56 (95 % CI: 0.45-0.68), 0.72 (95 % CI: 0.55-0.94), 0.85 (95 % CI: 0.72-0.99), 0.88 (95%CI: 0.73-1.04), 0.27 (95 % CI: 0.03-2.18), and 0.97 (95 % CI: 0.81-1.16), respectively. The AOR of receiving MOUD for all minorities compared to Whites was 0.70 (95 % CI: 0.61-0.80). Overall AOR comparing MOUD for females to males was 0.95 (95 % CI: 0.87-1.04). The second category of articles compared buprenorphine and methadone treatment among ethnic/racial minorities and Whites.

CONCLUSIONS

Compared to Whites, Blacks, Hispanics, and Asians have limited access to MOUD. The findings suggest that methadone is the predominant medication for racial/ethnic minorities, while Whites and high-income communities receive buprenorphine more. It is crucial to re-design policies to bridge the gap in access to MOUD.

Predictors and motives of polydrug use in opioid users. A narrative review

PURPOSE OF REVIEW

To review the recent literature on predictors and personal motives of polydrug use in opioid users with a focus on combined use of opioids with stimulants, benzodiazepines and gabapentinoids.

RECENT FINDINGS

In North America, methamphetamine is now the most prevalent co-drug in opioid users and is responsible for high mortality rates. In Europe, opioids are rather combined with either cocaine, benzodiazepines or gabapentionoids, but recent data are lacking.Main personal motives of opioid users to combine opioids with methamphetamine or cocaine is to boost the opioid high, inhibit the withdrawal effects of heroin and have a cheaper alternative to maintain the opioid high. Risk factors of polydrug use by opioid users included being male, younger age, homelessness, high-risk sexual behavior, needle sharing, incarceration, poor mental health and recent use of cocaine or prescription opioids. The motives for co-use of opioids and gabapentinoids also include seeking a better high, lower price and to self-medicate pain/physical symptoms, including those resulting from withdrawal.

SUMMARY

When treating opioid users with polydrug drug use, special attention should be paid to dosing when in opioid agonist methadone/buprenorphine treatment and to the presence of physical pain. The validity of part of the personal motives seems questionable which deserves attention when counselling opioid users with polydrug use.

Social Cognition in Opioid Use Disorder

Background: Opioid use disorder (OUD) is associated with significant functional impairment and neurocognitive dysfunction, but only a handful of studies have investigated social cognitive abilities in this condition. This study aimed to investigate facial emotion recognition accuracy/biases and two different aspects of theory of mind (ToM) (ToM-decoding vs ToM-reasoning) in people with recovered OUD. Methods: The participants included 32 people with recovered OUD who were on Buprenorphine + Naloxone (B/N) maintenance treatment and 32 healthy controls. In addition to neurocognitive tasks, both groups were assessed by a facial emotion recognition task, the faux pas recognition task, and the reading the mind from the eyes task. Results: In comparison to healthy controls, people on B/N maintenance treatment showed deficits in facial emotion recognition (d = 1.32) and both aspects of ToM (d = 0.87-1.21). In analyses of individual emotions, people on B/N maintenance treatment had decreased accuracy in recognition of anger and fear and had a bias to identify other emotions as sad. The duration of opioid use was robustly associated with difficulties in the recognition of anger. Conclusion: People in B/N maintenance treatment have significant difficulties in recognizing the emotions and mental states of others. Deficits in social cognition might be important for understanding the difficulties in interpersonal and social functioning in people with OUD.

Predictors of Long-Term Opioid Use After Hospitalization for Traumatic Injury in a Racially and Ethnically Diverse Population: A 12-Month Prospective Observational Study

BACKGROUND

Long-term prescription opioid use is a significant risk factor for opioid morbidity and mortality, and severe traumatic injury is an important initiation point for prescription opioid use. This study examines predictors of long-term prescription opioid use among a racially and ethnically diverse population of patients hospitalized for traumatic injury.

METHODS

Study participants (N= 650) from two urban Level I trauma centers were enrolled. Baseline information on demographics, injury characteristics, self-reported pre-injury substance use and mental health, and personality characteristics and attitudes was collected through interviews during the initial hospitalization. Patients were interviewed again at 3 months and 12 months and asked about prescription opioid use in the prior 7 days. Multivariable logistic regressions assessed participants' baseline characteristics associated with opioid use at one or more follow-up interviews.

RESULTS

Pre-injury use of prescription painkillers had the strongest association with prescription opioid use at follow-up (adjusted odds ratio: 3.10; 95% confidence interval: 1.86-5.17). Older age, health insurance coverage at baseline, length of hospitalization, higher current pain level, pre-injury post-traumatic stress disorder symptoms, and discharge to a location other than home were also associated with significantly higher odds of prescription opioid use at follow-up.

CONCLUSIONS

Providers could consider screening for past use of prescription pain relievers and post-traumatic stress disorder before hospital discharge to identify patients who might benefit from additional resources and support. However, providers should ensure that these patients' pain management needs are still being met and avoid abrupt discontinuation of prescription opioid use among those with a history of long-term use.