Gender differences in mortality among treated opioid dependent patients

Increased cancer incidence and mortality among people with opioid use-related disorders: A nation-wide cohort study

BACKGROUND AND AIMS

Studies on cancer incidence and mortality among people with opioid use-related disorders are lacking. We aimed to measure cancer-specific incidence, mortality and survival among people diagnosed with opioid use-related disorders in Norway during 2010-18.

DESIGN AND SETTING

This was a cohort study conducted in Norway during 2010-18.

PARTICIPANTS

Individuals (n = 20 710) diagnosed with opioid use-related disorders.

MEASUREMENTS

We conducted a cohort study utilizing a data-linkage of national health and population registers. Information on opioid use-related disorders was extracted from specialized healthcare, malignancies from the Cancer Registry of Norway and deaths from Cause of Death Registry. Cancer incidence and mortality were compared with the general population by calculating sex-specific age-standardized incidence (SIR) and mortality (SMR) ratios. One-year survival rates were computed.

FINDINGS

Compared with the general population, people with opioid use-related disorders were at an increased risk of developing cancer overall [SIR = 1.2, 95% confidence interval (CI) = 1.1-1.3] with a higher than twofold cancer mortality rate (SMR = 2.3, 95% CI = 2.0-2.7). Excess risk was observed for liver (12.6, 95% CI = 9.1-17.0), larynx (4.7, 95% CI = 1.7-10.2), lung (3.5, 95% CI = 2.8-4.3) and pancreas cancer (2.6, 95% CI = 1.6-4.0), whereas reduced risk was found for melanoma (0.5, 95% CI = 0.3-0.9), breast (0.6, 95% CI = 0.4-0.9) and prostate cancers (0.3, 95% CI = 0.1-0.4). Site-specific SMRs were significantly elevated for liver (12.3, 95% CI = 8.5-17.2), lung (3.9, 95% CI = 3.0-5.0), pancreas (3.0, 95% CI = 1.7-4.8) and colon cancers (1.9, 95% CI = 1.1-3.1). The average 1-year survival rate after a cancer diagnosis was low in liver, pancreas and colon cancer, ranging from 10 to 15% less than that of the general population.

CONCLUSIONS

In Norway, cancer incidence and cancer-related mortality appear to be elevated among individuals with opioid use-related disorders.

Molecular Sex Differences and Clinical Gender Efficacy in Opioid Use Disorders: From Pain Management to Addiction

Opioids have been utilized for both medical and recreational purposes since their discovery. Primarily recognized for their analgesic properties, they are also associated with the development of tolerance and dependence, contributing to a significant public health concern worldwide. Sex differences in opioid use disorder reveal that while men historically exhibit higher rates of abuse, women may develop dependence more quickly and are more susceptible to the addictive nature of opioids. This narrative review explores sex differences in opioid response in both clinical and experimental models, focusing on opioid receptor mechanisms, pain modulation, and hormonal influences. Additionally, it discusses the complexities of opioid addiction and withdrawal, highlighting sex-specific responses and the role of opioid replacement therapies. Diverse experimental outcomes, together with observational data, underscore the need for further research into sex-specific opioid biological mechanisms in a wider context, including demographic, cultural, and health-related factors. A comprehensive understanding of these complexities holds the potential to enhance personalized opioid therapies.

Predictors of Death From Physical Illness or Accidental/Intentional Causes Among Patients With Substance-Related Disorders

OBJECTIVE

This study identified patient clinical and sociodemographic characteristics, and, more originally, service use patterns as predictors of death from physical illness or accidental/intentional causes.

METHODS

A cohort of 19,015 patients with substance-related disorders (SRD) from 14 addiction treatment centers was investigated using Quebec (Canada) health administrative databases. Death was studied over a 3-year period (April 1, 2013, to March 31, 2016), and most predictors from 4 years to 12 months prior to the time of death, using multinomial logistic regression.

RESULTS

Frequent emergency department (ED) use strongly predicted both causes of death, suggesting that outpatient care responded inadequately to patient needs. Only receipt of specialized SRD and psychiatric care significantly decreased the risk of death from physical illness, with trends toward significance for accidental/intentional death. Hospitalization, greater material deprivation and having SRD-chronic physical illnesses or alcohol-related disorders most strongly predicted risk of death from physical illness. Sociodemographic characteristics, mainly social deprivation, were more likely to predict accidental/intentional death.

CONCLUSIONS

Outpatient services could be improved by increasing outreach and motivational interventions and, for ED and hospital units, better screening, brief intervention, and referral to treatment, particularly for men and socially deprived patients at high risk of accidental/intentional death. Patients with more severe health conditions, notably older or materially deprived men at higher risk of death from physical illness, could benefit from programs like assertive community treatment or intensive case management that respond well to diverse and continuous patient needs. Collaborative care between SRD and health services could also be improved.

Effect of HCV or HIV infection on mortality among hospitalized persons who used opioids, 2000-2010

Mortality due to opioid misuse and overdose has increased substantially in the United States over the past two decades. The study objective was to describe the causes of death among persons with opioid-related hospitalizations and examine survival by Hepatitis C virus (HCV) or HIV. Opioid-related hospitalization records in Pennsylvania from 2000 to 2010 were linked to death registry files to assess cause of death, and survival from first hospital discharge date to death date, or December 31, 2010. Accelerated failure time models were used to compare survival between persons with and without HCV or HIV diagnoses. Among the 136,416 individuals with an opioid-related hospitalization, 13.0% died over a median of 56 months of follow-up; the most common causes of death were circulatory diseases (26.4%) and drug overdose (23.5%). There were 27,122 (19.9%) and 3662 (2.7%) persons who had an HCV and HIV diagnosis, respectively. Among patients aged ≥20 years, those with HCV had shorter survival time compared to those without HCV, with discrepancies more pronounced at older ages. Patients with HIV also had shorter survival time (time ratio: 0.29 [95% CI: 0.26, 0.34]) compared to without HIV. These findings show that in a cohort of patients with opioid-related hospitalizations, those with HCV or HIV diagnoses have shorter survival. This has public health implications, providing further evidence that medical providers should educate patients who use opioids about the risks of HCV and HIV infection and focus prevention and treatment to decrease mortality among patients hospitalized for opioid use.

Women-Reported Barriers and Facilitators of Continued Engagement with Medications for Opioid Use Disorder

Opioid-related fatalities increased exponentially during the COVID-19 pandemic and show little sign of abating. Despite decades of scientific evidence that sustained engagement with medications for opioid use disorders (MOUD) yields positive psychosocial outcomes, less than 30% of people with OUD engage in MOUD. Treatment rates are lowest for women. The aim of this project was to identify women-specific barriers and facilitators to treatment engagement, drawing from the lived experience of women in treatment. Data are provided from a parent study that used a community-partnered participatory research approach to adapt an evidence-based digital storytelling intervention for supporting continued MOUD treatment engagement. The parent study collected qualitative data between August and December 2018 from 20 women in Western Massachusetts who had received MOUD for at least 90 days. Using constructivist grounded theory, we identified major themes and selected illustrative quotations. Key barriers identified in this project include: (1) MOUD-specific discrimination encountered via social media, and in workplace and treatment/recovery settings; and (2) fear, perceptions, and experiences with MOUD, including mental health medication synergies, internalization of MOUD-related stigma, expectations of treatment duration, and opioid-specific mistrust of providers. Women identified two key facilitators to MOUD engagement: (1) feeling "safe" within treatment settings and (2) online communities as a source of positive reinforcement. We conclude with women-specific recommendations for research and interventions to improve MOUD engagement and provide human-centered care for this historically marginalized population.

Systematic review of guidelines for managing physical health during treatment for substance use disorders: Implications for the alcohol and other drug workforce

ISSUES

Substance use disorders are associated with significant physical health comorbidities, necessitating an integrated treatment response. However, service fragmentation can preclude the management of physical health problems during addiction treatment. The aim of this systematic review was to synthesise the recommendations made by clinical practice guidelines for addressing the physical health of people attending alcohol and other drug (AOD) treatment.

APPROACH

An iterative search strategy of grey literature sources was conducted from September 2020 to February 2021 to identify clinical practice guidelines. Content pertaining to physical health care during AOD treatment was extracted. Quality of guidelines were appraised using the Appraisal of Guidelines Research and Evaluation II (AGREE-II) tool.

FINDINGS

Thirty-three guidelines were included for review. Fourteen guidelines were considered high quality based on AGREE-II scores. Neurological conditions (90.9%) and hepatitis (81.8%) were the most frequent health problems addressed. Most guidelines recommended establishing referral pathways to address physical health comorbidities (90.9%). Guidance on facilitating these referral pathways was less common (42.4%). Guidelines were inconsistent in their recommendations related to oral health, tobacco use, physical activity, nutrition and the use of standardised assessment tools.

IMPLICATIONS AND CONCLUSIONS

Greater consistency and specificity in the recommendations made for integrating physical health care within addiction treatment is needed. Ensuring that recommendations are applicable to the AOD workforce and to treatment services limited by funding and resource constraints should enhance implementation. Future guideline development groups should consider increased consultation with the AOD workforce and inclusion of clinical tools and decision aids to facilitate referral pathways.

Gender-specific correlates of nonmedical use of prescription medications in a diverse primary care sample

BACKGROUND

Nonmedical use of prescription medications (NUPM) is a growing problem but little is known about its gender-specific mechanisms despite NIDA's call for gender-stratified research over a decade ago. We explored gender differences in NUPM in a diverse sample of primary care patients.

METHODS

N = 4458 participants participated in an anonymous health survey in urban primary care clinics. The primary outcome was past month NUPM. All analyses were stratified by gender. Bivariate relationships among NUPM and demographic, medical, psychological, and substance use-related variables were analyzed. Stepwise multivariate logistic regression models (LRMs) were estimated by gender.

RESULTS

More men (9.5%) reported NUPM than women (7.4%). The final LRM among men included age (OR=0.98), race (OR=0.49), chronic pain diagnosis (OR=1.73), hepatitis (OR=1.78), depression diagnosis (OR=1.77), positive alcohol misuse screen (OR=1.58), and mood disturbance (OR=1.04). Among women, the model included mood disturbance (OR=1.04), illicit drug use (OR=2.22), family history of drug problems (OR=1.41), and heart disease diagnosis (OR=0.48). Effect sizes ranged from small to moderate.

CONCLUSIONS

Among a sample of primary care patients, gender-stratified analyses indicated differential presentation of NUPM by gender. Demographic factors were more relevant correlates among men, with younger, White men at higher risk. Chronic pain and depression were more notable risk factors for men. Recent illicit drug use and family history of drug problems were uniquely associated among women, while recent distress was a strong correlate among both men and women. A better understanding of gender-specific correlates of NUPM can inform gender-tailored prevention and treatment efforts.

Polysubstance Use Among Patients Treated With Buprenorphine From a National Urine Drug Test Database

IMPORTANCE

Polysubstance use is a concern for patients treated for opioid use disorder (OUD). While buprenorphine can curtail harmful opioid use, co-occurring use of nonprescribed substances, such as cocaine, methamphetamine, and other opioids, may negatively affect treatment outcomes.

OBJECTIVE

To characterize factors associated with urine drug positivity for nonprescribed substances among patients prescribed buprenorphine.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study included patients who had been prescribed buprenorphine and who provided urine specimens for urine drug testing (UDT), as ordered by clinicians in primary care or behavioral health or at substance use disorder treatment centers, from 2013 to 2019. Specimens were analyzed by liquid chromatography-tandem mass spectrometry to assess positivity for several commonly used substances.

EXPOSURES

Buprenorphine prescription.

MAIN OUTCOMES AND MEASURES

Positivity for buprenorphine and several nonprescribed substances. Unadjusted trends in positivity for each nonprescribed substance were compared between specimens that did and did not test positive for buprenorphine. Multivariable logistic regression was used to examine factors associated with positivity; factors included patient age, sex, setting of care, payer, collection year, and census division.

RESULTS

The study included first UDT specimens from 150 000 patients, of whom 82 107 (54.74%) were men and 77 300 (51.53%) were aged 18 to 34 years. Across all specimens, 128 240 (85.49%) were positive for buprenorphine, and 71 373 (47.58%) were positive for 1 or more nonprescribed substances. From 2013 to 2019, positivity rates increased for most substances (eg, fentanyl: from 131 of 21 412 [0.61%] to 1464 of 13 597 [10.77%]). Factors associated with positivity varied widely by substance; for example, fentanyl positivity was highest for men (OR, 1.13; 95% CI, 1.06-1.21), patients aged 18 to 24 years (OR for patients ≥55 years, 0.46; 95% CI, 0.39-0.54), patients living in New England (OR, 1.19; 95% CI, 1.07-1.33), and patients with Medicaid (OR, 1.20; 95% CI, 1.11-1.31), whereas oxycodone positivity was greatest for women (OR for men, 0.84; 95% CI, 0.79-0.89), patients older than 55 years (OR, 1.42; 95% CI, 1.22-1.64), patients living in the South Atlantic (OR, 1.45, 95% CI, 1.33-1.58), and patients with private insurance (OR for Medicaid, 0.78; 95% CI, 0.73-0.84). Patients whose specimens were positive for buprenorphine were significantly less likely to be positive for other opioids (eg, fentanyl: OR for buprenorphine-negative samples, 6.71; 95% CI, 6.29-7.16; heroin: OR for buprenorphine-negative samples, 9.93; 95% CI, 9.31-10.59).

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, patterns of nonprescribed substance positivity among patients prescribed buprenorphine varied widely. This study highlights the utility of UDT in public health surveillance efforts related to patients treated with buprenorphine for OUD.

Chronic Pain, Opioid Use Disorder, and Clinical Management Among Older Adults

Because of unique factors related to physiological changes and altered metabolism in advanced age, special attention is needed concerning chronic pain, opioid use, and opioid use disorder among older adults. Clinicians need to follow the most updated clinical guidelines regarding opioid prescribing. Routine screening and awareness are the keys to identifying opioid use disorder. Comprehensive assessments often require both pain assessment (including functional status) and substance use assessment, including the use of urine toxicological testing and structured, validated screening tools and instruments. Comprehensive, interdisciplinary efforts are critical in managing the care of older adults with chronic pain and opioid use disorder. A collaborative approach that includes substance abuse treatment and pain management (including pain subspecialty care) is often recommended. Medications for opioid use disorder have been extensively studied and have the most convincing evidence to date, and psychosocial treatments may be beneficial in some circumstances.

Competing risks of women and men who use fentanyl: "The number one thing I worry about would be my safety and number two would be overdose"

BACKGROUND

Standard public health approaches to risk communication do not address the gendered dynamics of drug use. The aim of this study was to explore perceptions of fentanyl-related risks among women and men to inform future risk communication approaches.

METHODS

We conducted a qualitative study, purposively sampling English-speaking women and men, aged 18-25 or 35+ years, with past 12-month illicitly manufactured fentanyl use. In-depth individual interviews explored experiences of women and men related to overdose and fentanyl use. We conducted a grounded content analysis examining specific codes related to overdose and other health or social risks attributed to drug use. Using a constant comparison technique, we explored commonalities and differences in themes between women and men.

RESULTS

The study enrolled twenty-one participants, 10 women and 11 men. All participants had personal overdose experiences. Both women and men described overdosing as a "chronic" condition and expressed de-sensitization to the risk of overdose. Women and men described other risks around health, safety, and state services that often superseded their fear of overdose. Women feared physical and sexual violence and prioritized caring for children and maintaining relations with child protective services, while men feared violence arising from obtaining and using street drugs and incarceration. Only women reported that fear of violence prevented their utilization of harm reduction services.

CONCLUSIONS

Experiences with overdose and risk communication among people who use fentanyl-containing opioids varied by gender. The development of gender-responsive programs that address targeted concerns may be an avenue to enhance engagement with harm reduction and treatment services and create safe spaces for women not currently accessing available services.

Opioid Exposures Reported to U.S. Poison Centers

OBJECTIVE

Opioid-related deaths are a leading cause of accidental deaths in the United States (U.S.). This study aims to examine the national trends in opioid exposures reported to U.S. poison centers (PCs).

METHODS

The National Poison Data System (NPDS) was queried for opioid exposures between 2011 and 2018. We descriptively assessed the demographic and clinical characteristics. Trends in opioid frequencies and rates were analyzed using Poisson regression. Independent predictors of serious adverse events in opioid exposures were studied.

RESULTS

There were a total of 604,183 opioid exposure calls made to the PCs during the study period. The frequency of opioid exposures decreased by 28.9% (95% CI: -29.6%, -28.1%; p < 0.001), and the rate of opioid exposures decreased by 21.2% (95% CI: -24.7%, -16.9%; p < 0.001). Multiple substance exposures accounted for 48.9% cases. The most frequent age group was 20-29 years (19.3%). Suspected suicides accounted for 34.9% cases. There were 7,246 deaths in our study sample, with 6.8% of cases demonstrating major effects. Hydrocodone was the most frequently observed opioid causing a toxic exposure and naloxone was used in 20.6% cases. Important predictors of a serious adverse event were age, gender, multi-substance exposures, and reasons for exposure.

CONCLUSIONS

Analysis of calls to PCs indicated a decreasing trend of opioid exposures. However, the proportion of SAEs due to such exposures increased. There was a high proportion of intentional exposures and occurred in older age groups. PCs are a vital component of real-time public health surveillance of overdoses in the current opioid crisis.

Gender Differences on Methadone Maintenance Treatment Outcome among Patients with Opioid use Disorder: A Systematic Review

OBJECTIVES

The objective of this study was to review the significant differences of MMT outcomes related to drug use behavior, health status, and social behavioral functioning between genders.

MATERIALS AND METHODS

A search of publication was conducted in PubMed/MEDLINE, Embase, CINAHL, PsycINFO, and Scopus database. Two reviewers independently screened the titles, abstracts, and keyword use for the search. Inclusion of studies was based on randomized controlled trials (RCTs) or observational studies that report the difference of opioid addiction treatment outcomes between genders. Any conflict between the two reviewers was resolved through discussion and consensus. The systematic review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines and was registered in PROSPERO with a registration number CRD42019116261.

RESULTS

A total of 25 studies were evaluated as part of qualitative synthesis. The review resulted in three main themes, which are (1) improving well-being and methadone-related outcome (five subthemes), (2) impact on social and behavioral (four subthemes), and (3) illicit drug use pattern-related behavior (four subthemes).

CONCLUSION

This review will highlight how men and women differ in methadone treatment outcomes for further application and improvement in the clinical setting.

Severe intimate partner violence is associated with all-cause mortality among women living with HIV

OBJECTIVE

To examine the independent association between intimate partner violence (IPV) severity and all-cause mortality among women living with HIV (WLHIV).

DESIGN

Cross-sectional questionnaire linked to longitudinal vital statistics data.

METHODS

We examined the lifetime prevalence of IPV and age-standardized all-cause mortality rates by IPV severity reported by WLHIV. Lifetime IPV (emotional/verbal, physical, or sexual) severity was assessed as a categorical variable: no history of any IPV (none); experienced one or two forms of IPV (moderate); or experienced all three forms of IPV (severe IPV). Two separate logistic regression models examined associations between any IPV (vs. none) as well as IPV severity (none vs. moderate, severe) and all-cause mortality.

RESULTS

At the time of interview (2007-2010), 260 participants self-identified as women with a median (Q1-Q3) age of 41 years (35-46). Of these women, the majority were unemployed (85%), 59% reported any IPV and 24% reported severe IPV. Of the 252 women followed until 31 December 2017, 25% (n = 63) died. Age-standardized all-cause mortality rates for WLHIV who experienced severe IPV were two-times higher than women with no history of IPV (44.7 per 1000 woman-years vs. 20.9 per 1000 woman-years). After adjustment for confounding, experiences of severe IPV (vs. none) were significantly associated with all-cause mortality (aOR = 2.42, 95% CI = 1.03-5.70).

CONCLUSION

Although we found that any lifetime experience of IPV was not associated with all-cause mortality, women ever experiencing severe IPV were significantly more likely to die during the study period. This may suggest a need for increased trauma- and violence-aware approaches.

Place, poverty and prescriptions: a cross-sectional study using Area Deprivation Index to assess opioid use and drug-poisoning mortality in the USA from 2012 to 2017

OBJECTIVE

To identify the relationships between county-level area deprivation and patterns of both opioid prescriptions and drug-poisoning mortality.

DESIGN, SETTING AND PARTICIPANTS

For this retrospective cross-sectional study, we used the IQVIA Xponent data to capture opioid prescriptions and Centres for Disease Control and Prevention National Vital Statistics System to assess drug-poisoning mortality. The Area Deprivation Index (ADI) is a composite measure of social determinants of health comprised of 17 US census indicators, spanning four socioeconomic domains. For all US counties with available opioid prescription (2712 counties) and drug-poisoning mortality (3133 counties) data between 2012 and 2017, we used negative binomial regression to examine the association between quintiles of county-level ADI and the rates of opioid prescriptions and drug-poisoning mortality adjusted for year, age, race and sex.

PRIMARY OUTCOME MEASURES

County-level opioid prescription fills and drug-poisoning mortality.

RESULTS

Between 2012 and 2017, overall rates of opioid prescriptions decreased from 96.6 to 72.2 per 100 people, while the rates of drug-poisoning mortality increased from 14.3 to 22.8 per 100 000 people. Opioid prescription and drug-poisoning mortality rates were consistently higher with greater levels of deprivation. The risk of filling an opioid prescription was 72% higher, and the risk of drug-poisoning mortality was 36% higher, for most deprived compared with the least deprived counties (both p<0.001).

DISCUSSION

Counties with greater area-level deprivation have higher rates of filled opioid prescriptions and drug-poisoning mortality. Although opioid prescription rates declined across all ADI quintiles, the rates of drug-poisoning mortality continued to rise proportionately in each ADI quintile. This underscores the need for individualised and targeted interventions that consider the deprivation of communities where people live.

Living a normal life? Follow-up study of women who had been in opioid maintenance treatment during pregnancy

BACKGROUND

There are few longitudinal follow-up studies of patients in opioid maintenance treatment (OMT). For this reason we performed a follow-up study of a cohort of 67 women who had used OMT-medications during pregnancy an average of ten years earlier. The aim of our study was to explore how the women were doing over time regarding OMT medication adherence and use of other legal and illegal substances, as well as to evaluate the mortality for the women and custody situation for the children in the cohort.

METHODS

Participants were recruited from two cohorts in our previous pregnancy study covering women who gave birth from 2004 to 2009. Sixty-seven women agreed to be interviewed, which is 73% of the eligible women from our original study. We developed a questionnaire, which we used in the interview, that focused primarily on these women's current life situation (custody of child they had delivered, the use of medications in OMT and other legal and illegal substances, and several other health and social aspects of the participants' lives).

RESULTS

Two women had died prior to the follow-up. Eighty-one percent of the women had custody of the child they had delivered in our pregnancy study and half the women were single parents. Fifty-four percent of the women were employed. At follow-up, 42% of the women were in methadone maintenance treatment (MMT), 39% were in buprenorphine maintenance treatment (BMT), and 19% had left OMT. One-third of the women had changed their OMT medication during the follow-up period. The majority (77%) were satisfied with their current OMT medication. The women in MMT seemed to be more severe substance dependent than the rest of the participants. There was little use of legal and illegal substances at follow-up, especially among women with custody of their child. The frequency of substance use was low. Fourteen percent of the women were in the process of leaving OMT and another half of the women wanted to leave OMT, but had no plan for how and when.

CONCLUSION

This follow-up study describes a predominantly well rehabilitated cohort of women who had given birth while in OMT ten years earlier. The majority of the women had custody of their children and used very few legal and illegal drugs. Our findings may be explained partly from a life course perspective, with the women having experienced turning points when starting OMT or becoming mothers.

Substance Use and Co-occurring Physical Health Problems: File Review of a Residential Drug and Alcohol Treatment Service

Objectives: Physical health conditions cause significant disability and mortality among people living with alcohol and other drug problems. There has been limited research on the prevalence of health problems among clinical samples of people with substance use disorders, particularly among those in residential treatment. Yet residential settings provide unique opportunity for responding to health needs. To better understand the health of people attending treatment for substance use disorders, this study conducted a file review to examine the prevalence of physical health problems as identified during routine residential care. Methods: A retrospective review of client files collected between 2013 and 2017 (N = 172) was completed at a residential treatment service in NSW, Australia. Data were extracted to examine the prevalence of physical health problems recorded at entry into treatment. Correlates of health problems were estimated using bivariate descriptive analyses and logistic regression. Results: The majority of clients in treatment for substance use had a comorbid physical health problem (80.7%). Musculoskeletal problems were the most frequently reported medical issue (38.6%). Odds for some physical health problems were related to client gender, age, and primary substance of concern. Male gender remained the strongest predictor of dental health problems when controlling for age and substance type (odds ratio [OR] = 3.60). Primary alcohol use remained the strongest predictor of nutritional deficiencies when controlling for client age (OR = 4.43). Among clients with a physical health problem and who had a treatment episode of at least 14 days (n = 110), just over half (55.5%) were referred to a health-related practitioner or service during their treatment episode. Conclusions: This study contributes to the literature by reporting on the incidence of physical health problems among people in residential treatment for substance use disorders. The high prevalence of physical health morbidity iterates the role of non-medical staff working within drug and alcohol services in the identification of client health needs. The findings support calls for systematic screening of physical health as part of routine care for substance use disorders improved integration of substance treatment and the broader primary health care system.

Interaction effects in the association between methadone maintenance therapy and experiences of racial discrimination in U.S. healthcare settings

BACKGROUND

Disparities in methadone maintenance therapy (MMT) outcomes have received limited attention, but there are important negative outcomes associated with MMT that warrant investigation. Racial discrimination is common in healthcare settings and affects opioid use disorder (OUD) treatment and comorbidities. However, race/ethnicity alone may not fully explain experiences of discrimination. MMT remains highly stigmatized and may compound the effect of race/ethnicity on discrimination in healthcare settings. We sought to quantify differential associations between MMT and experiences of racial discrimination between racial/ethnic groups in a U.S. national sample.

METHODS

We used the National Epidemiologic Survey on Alcohol and Related Conditions-III (2012-2013) to identify a subset of individuals with a lifetime OUD who had ever used MMT (survey n = 766; weighted population n = 5,276,507). We used multivariable logistic regression to model past-year experience of racial discrimination in a healthcare setting. We included an interaction term between race/ethnicity and MMT status to identify the odds of discrimination (MMT vs. no MMT [referent]) within racial/ethnic groups. We used survey procedures with weights to account for the parent study's complex survey design.

FINDINGS

Twenty-two percent of our sample experienced racial discrimination in a healthcare setting in the past year. Discrimination was more common among those who had ever used MMT (x2 = 10.00, p = 0.001) and racial/ethnic minorities (x2 = 23.15, p<0.001). The interaction effect was much stronger than the main effects of race/ethnicity and MMT status. MMT status (versus no MMT) was positively associated with discrimination among Blacks (aOR = 3.93, 95% CI = 3.87-3.98, p<0.001), Whites (aOR = 2.25, 95% CI = 2.23-2.27, p<0.001), and Latino/Latinas (aOR = 1.59, 95% CI = 1.55-1.62, p<0.001). Among American Indian/Alaska Natives (AI/AN), those who had used MMT had over thirty times the odds of racial discrimination, compared to their non-MMT counterparts (aOR = 32.78, 95% CI = 31.16-34.48, p<0.001).

CONCLUSION

Race/ethnicity alone did not sufficiently account for racial discrimination in healthcare settings among those with a lifetime OUD. MMT status was strongly associated with racial discrimination among AI/AN. Our strong interaction effect is indicative of an additional barrier to health services utilization among AI/AN, which has important implications for OUD treatment outcomes and comorbidities. Health promotion programs aimed at increased adoption of MMT are promising, but should be considered in the context of racial/ethnic disparities, drug use and MMT stigma, and implicit biases in clinical settings.

Increases in methamphetamine use among heroin treatment admissions in the United States, 2008-17

BACKGROUND AND AIMS

Due to their small sample sizes, geographic specificity and limited examination of socio-demographic characteristics, recent studies of methamphetamine use among people using heroin in the United States are limited in their ability to identify national and regional trends and to characterize populations at risk for using heroin and methamphetamine. This study aimed to examine trends and correlates of methamphetamine use among heroin treatment admissions in the United States.

DESIGN

Longitudinal analysis of data from the 2008 to 2017 Treatment Episode Data Set. Descriptive statistics, trend analyses and multivariable logistic regression were used to examine characteristics associated with methamphetamine use among heroin treatment admissions.

SETTING

United States.

PARTICIPANTS

Treatment admissions of people aged ≥ 12 years whose primary substance of use is heroin.

MEASUREMENTS

Primary measurement was heroin treatment admissions involving methamphetamine. Secondary measurements were demographics of sex, age, race/ethnicity, US census region, living arrangement and employment status.

FINDINGS

The percentage of primary heroin treatment admissions reporting methamphetamine use increased each year from 2.1% in 2008 to 12.4% in 2017, a relative percentage increase of 490% and an annual percentage change (APC) of 23.4% (P < 0.001). During the study period, increases were seen among males and females and among all demographic and geographic groups examined. Among primary heroin treatment admissions reporting methamphetamine use in 2017, 47.1% reported injecting, 46.0% reported smoking, 5.1% reporting snorting and 1.8% reported oral/other as their usual route of methamphetamine use.

CONCLUSIONS

Methamphetamine use among heroin treatment admissions in the United States increased from one in 50 primary heroin treatment admissions in 2008 to one in 8 admissions in 2017.

Racial/Ethnic and Gender Differences in Associations of Medication-Assisted Therapy and Reduced Opioid Use between Outpatient Treatment Admission and Discharge

Medication-assisted therapy (MAT) for opioid use disorders is an effective treatment strategy. Racial/ethnic and gender disparities in MAT utilization have been documented, but less is known about disparities in MAT outcomes. We used the Treatment Episodes Dataset-Discharges (TEDS-D; 2015- 2017) to identify outpatient treatment episodes with heroin or illicit opioids indicated at admission (n = 232,547). We used multivariate logistic regression to model the association between MAT and a reduction in opioid use between treatment admission and discharge. We explored moderation by race/ethnicity and gender by including an interaction term. We identified a strong moderating effect of race/ethnicity and gender. American Indian/Alaska Native (AI/AN) women demonstrated the strongest association between MAT (versus no MAT) and a reduction in opioid use (aOR = 6.05, 95% CI = 4.81- 7.61), while White men demonstrated the weakest association (aOR = 2.78, CI = 2.70- 2.87). Our findings could inform changes in clinical MAT settings that are based on harm reduction and the incremental transition from illicit opioids to medication-assistance among a diverse opioid use disorder population.

Unmet substance use disorder treatment need among reproductive age women

BACKGROUND

Substance use disorder (SUD) is a chronic medical condition in need of long-term treatment. The objective of the study is to describe the current unmet SUD treatment need among reproductive age women living in the United States with a focus on pregnancy and parenting status.

METHODS

Data were drawn from the 2007-2014 National Survey of Drug Use and Health for women 18-44 years old. The primary outcomes were past year SUD treatment need and receipt. Women with a SUD treatment need included those with a SUD and/or expressing a need for SUD treatment. Women were classified as pregnant, parenting (living with their children) or not pregnant nor parenting. Multivariable logistic regression determined if pregnancy/parenting status was associated with treatment need and receipt controlling for demographic factors.

RESULTS

Among reproductive age women with a past year SUD treatment need, only 9.3 % (95 % CI 8.4-10.2 %) received treatment. Pregnant and parenting women were not more likely to receive treatment (pregnant AOR 0.9; 95 % CI 0.5-1.8 & parenting AOR 0.7; 95 % CI 0.5-0.9) compared to not pregnant nor parenting women. Black (AOR 0.3; 95 % CI 0.2-0.5) and Hispanic women (AOR 0.6; 95 % CI 0.4-0.9) were less likely to receive treatment.

CONCLUSIONS

Few reproductive age women who need SUD treatment receive it in the US. Although pregnant women are considered a priority population, they are not receiving priority services. Racial disparities in unmet SUD treatment need exist. Barriers to SUD treatment, such as expanding gender informed services, must be addressed.

Reduction in mortality risk with opioid agonist therapy: a systematic review and meta-analysis

INTRODUCTION

Opioid agonist therapies are effective medications that can greatly improve the quality of life of individuals with opioid use disorder. However, there is significant uncertainty about the risks of cause-specific mortality in and out of treatment.

OBJECTIVE

This systematic review and meta-analysis explored the association between methadone and buprenorphine with cause-specific mortality among opioid-dependent persons.

METHODS

We searched six online databases to identify relevant cohort studies, calculating all-cause and overdose-specific mortality rates during periods in and out of treatment. We pooled mortality estimates using multivariate random effects meta-analysis of the crude mortality rate per 1000 person-years of follow-up as well as relative risks comparing mortality in vs. out of treatment.

RESULTS

A total of 32 cohort studies (representing 150 235 participants, 805 423.6 person-years, and 9112 deaths) met eligibility criteria. Crude mortality rates were substantially higher among methadone cohorts than buprenorphine cohorts. Relative risk reduction was substantially higher with methadone relative to buprenorphine when time in-treatment was compared to time out-of-treatment. Furthermore, the greatest mortality reduction was conferred during the first 4 weeks of treatment. Mortality estimates were substantially heterogeneous and varied significantly by country, region, and by the nature of the treatment provider.

CONCLUSION

Precautions are necessary for the safer implementation of opioid agonist therapy, including baseline assessments of opioid tolerance, ongoing monitoring during the induction period, education of patients about the risk of overdose, and coordination within healthcare services.

A latent class analysis of the past-30-day substance use patterns among lifetime cocaine users: Findings from a community sample in North Central Florida

Objectives

Cocaine use is increasing and many cocaine users engage in polysubstance use. Within polysubstance use, relationships among use of individual substances are necessarily complex. To address this complexity, we used latent class analysis (LCA) to identify patterns of polysubstance use among lifetime cocaine users and examine associations among these patterns, demographics, and risk profiles.

Methods

Members of HealthStreet, an ongoing community engagement program, were asked about lifetime and past 30-day use of cocaine, alcohol, tobacco, marijuana, and prescription medications, mental health conditions, recent Emergency Department (ED) visits and demographics. LCA was used to identify classes of past 30-day polysubstance use among individuals who endorsed lifetime cocaine use. Multinomial logistic regression identified factors associated with these classes.

Results

Among 1797 lifetime cocaine users, a five-class LCA model was identified: 1) past 30-day tobacco use only (45%), 2) past 30-day alcohol, marijuana and tobacco use (31%), 3) past 30-day tobacco, prescription opioid and sedative use (13%), 4) past 30-day cocaine, alcohol, marijuana and tobacco use (9%), 5) past 30-day cocaine and multiple polysubstance use (2%). Demographics, ED visits and mental health conditions were associated with class membership.

Conclusions

Approximately 11% of lifetime cocaine users used cocaine in the past 30 days with two different concurrent substance use patterns. Prescription medication (opioids and sedatives) and complex polysubstance use patterns were stronger indicators of negative outcomes than current cocaine use. Cocaine was not used frequently with other stimulants. In addition to polysubstance use, prescription medication use should be targeted for intervention among lifetime cocaine users.

Cost-effectiveness of hydromorphone for severe opioid use disorder: findings from the SALOME randomized clinical trial

BACKGROUND AND AIMS

Previous research has found diacetylmorphine, delivered under supervision, to be cost-effective in the treatment of severe opioid use disorder, but diacetylmorphine is not available in many settings. The Study to Assess Long-term Opioid Maintenance Effectiveness (SALOME) randomized controlled trial provided evidence that injectable hydromorphone is non-inferior to diacetylmorphine. The current study aimed to compare the cost-effectiveness of hydromorphone directly with diacetylmorphine and indirectly with methadone maintenance treatment.

DESIGN

A within-trial analysis was conducted using the patient level data from the 6-month, double-blind, non-inferiority SALOME trial. A life-time analysis extrapolated costs and outcomes using a decision analytical cohort model. The model incorporated data from a previous trial to include an indirect comparison to methadone maintenance.

SETTING

A supervised clinic in Vancouver, British Columbia, Canada.

PARTICIPANTS

A total of 202 long-term street opioid injectors who had at least two attempts at treatment, including one with methadone (or other substitution), were randomized to hydromorphone (n = 100) or diacetylmorphine (n = 102).

MEASUREMENTS

We measured the utilization of drugs, visits to health professionals, hospitalizations, criminal activity, mortality and quality of life. This enabled us to estimate incremental costs, quality-adjusted life years (QALYs) and cost-effectiveness ratios from a societal perspective. Sensitivity analyses considered different sources of evidence, assumptions and perspectives.

FINDINGS

The within-trial analysis found hydromorphone provided similar QALYs to diacetylmorphine [0.377, 95% confidence interval (CI) = 0.361-0.393 versus 0.375, 95% CI = 0.357-0.391], but accumulated marginally greater costs [$49 830 ($28 401-73 637) versus $34 320 ($21 780-55 998)]. The life-time analysis suggested that both diacetylmorphine and hydromorphone provide more benefits than methadone [8.4 (7.4-9.5) and 8.3 (7.2-9.5) versus 7.4 (6.5-8.3) QALYs] at lower cost [$1.01 million ($0.6-1.59 million) and $1.02 million ($0.72-1.51 million) versus $1.15 million ($0.71-1.84 million)].

CONCLUSIONS

In patients with severe opioid use disorder enrolled into the SALOME trial, injectable hydromorphone provided similar outcomes to injectable diacetylmorphine. Modelling outcomes during a patient's life-time suggested that injectable hydromorphone might provide greater benefit than methadone alone and may be cost-saving, with drug costs being offset by costs saved from reduced involvement in criminal activity.

Differences in mortality in a cohort of cocaine use disorder patients with concurrent alcohol or opiates disorder

AIMS

To study mortality in a cohort of cocaine use disorder patients, and compare results in those with concurrent alcohol or opiates disorder.

DESIGN, SETTING AND PARTICIPANTS

A cohort of 10 539 cocaine use disorder individuals entering drug treatment in public out-patient centres in the city of Barcelona was followed from 1997 to 2011. Participants were divided at baseline into three groups: those with only cocaine use disorder (CUD), those with cocaine and alcohol use disorder but not opioid (CAUD) and those with cocaine and opioid use disorder (COUD). Mortality was assessed through the Spanish National Mortality Register.

MEASUREMENTS

Crude mortality rates (CMR), standardized mortality ratios (SMR) and rate ratios (RR) were calculated for each group. A multivariable Cox regression model was fitted to obtain adjusted mortality hazard ratios (aHR) of CAUD and COUD with respect to CUD. Specific mortality causes were also examined.

FINDINGS

The total of 716 deaths registered resulted in a CMR = 6.0/1000 person-years (PY); 95% confidence interval (CI) = 5.1-7.0 for CUD, CMR = 5.8/1000 PY (95% CI = 4.9-6.7) for CAUD and CMR = 20.7/1000 PY (95% CI = 18.8-22.8) for COUD, with no significant differences among sexes. Compared with the general population, mortality was four times higher (SMR = 4.1, 95% CI = 3.5-4.8) among CUD, more than three times among CAUD (SMR = 3.4, 95% CI = 2.9-3.9) and more than 10 times among COUD (SMR = 11.6, 95% CI = 10.5-12.8), being always higher in women. External injuries, led by overdose, accumulated the biggest percentage of deaths among the three groups, but infectious diseases showed the highest excess mortality. Some differences regarding causes of death were observed between the three groups.

CONCLUSIONS

Mortality risk and excess mortality are significantly greater among those with cocaine and opiates use disorder than among people with only cocaine use disorder or cocaine and alcohol use disorder.

Veiled Truths: Iranian Women and Risky Sexual Behavior in the Context of Substance Use

BACKGROUND

Substance use disorders and risky sexual behavior coexist for some women. Explanatory models of women's sexuality in the context of substance use are under study. This study aimed to explore how women's sexual behavior can become risky in the context of substance use.

METHODS

In this ethnographic inquiry, 25 women with substance use disorders (SUDs) were included at two Drop-In-Centers (DICs) in South Tehran. Observation, semi-structured interviews and field notes were used to collect data. Qualitative content analysis was used to attain the explanatory model of women's sexual behaviors in the context of substance use.

RESULTS

Three major themes emerged from the data analysis regarding their lives in the context of substance use; 1) life in the context of drug abuse, 2) negative self-perception, and 3) strive to survive. Subthemes were identified as loss of contact with family, social stigma, self-forgetfulness, worthlessness, low self-efficacy, and unsafe sexual context.

CONCLUSION

Findings suggest that women with SUDs are highly interwoven with women's sexual health, facilitating a shift towards risky behaviors. Integration of safe sexual skills building programs with substance use treatment is needed.

The impact of cannabis use on patients enrolled in opioid agonist therapy in Ontario, Canada

Background

With the Canadian government legalizing cannabis in the year 2018, the potential harms to certain populations—including those with opioid use disorder—must be investigated. Cannabis is one of the most commonly used substances by patients who are engaged in medication-assisted treatment for opioid use disorder, the effects of which are largely unknown. In this study, we examine the impact of baseline and ongoing cannabis use, and whether these are impacted differentially by gender.

Methods

We conducted a retrospective cohort study using anonymized electronic medical records from 58 clinics offering opioid agonist therapy in Ontario, Canada. One-year treatment retention was the primary outcome of interest and was measured for patients who did and did not have a cannabis positive urine sample in their first month of treatment, and as a function of the proportion of cannabis-positive urine samples throughout treatment.

Results

Our cohort consisted of 644 patients, 328 of which were considered baseline cannabis users and 256 considered heavy users. Patients with baseline cannabis use and heavy cannabis use were at increased risk of dropout (38.9% and 48.1%, respectively). When evaluating these trends by gender, only female baseline users and male heavy users are at increased risk of premature dropout.

Interpretation

Both baseline and heavy cannabis use are predictive of decreased treatment retention, and differences do exist between genders. With cannabis being legalized in the near future, physicians should closely monitor cannabis-using patients and provide education surrounding the potential harms of using cannabis while receiving treatment for opioid use disorder.

Adverse childhood experience effects on opioid use initiation, injection drug use, and overdose among persons with opioid use disorder

INTRODUCTION

Adverse childhood experiences are associated with the development of substance use disorders. With opioid use disorder, a growing concern in the United States, we were interested in examining the relationship between adverse experiences and three landmarks of opioid use: age of opioid initiation, injection drug use, and lifetime overdose.

METHODS

Between May and December 2015, we interviewed consecutive persons seeking inpatient opioid detoxification. Participants were asked about age of opioid initiation, last month injection drug use, and lifetime history of overdose, and completed the ten-item Adverse Childhood Experience (ACE) questionnaire.

RESULTS

Participants (n=457) averaged 32.2 (±8.64) years of age, 71.3% were male, and 82.5% were non-Hispanic White. The mean score on the ACE scale was 3.64 (±2.75). Mean age at time of initiating opioid use was 21.7 (±7.1) years, 68.7% had injected drugs within the past month, and 39.0% had overdosed. After adjusting for age, gender, and ethnicity, the ACE score was inversely associated with age of initiating opioid use (b=-0.50, 95% CI -0.70; -0.29, p<.001), and positively associated with recent injection drug use (OR=1.11, 95% CI 1.02; 1.20, p=0.014) and the likelihood of experiencing an overdose (OR=1.10, 95% CI 1.02; 1.20, p=0.015) in a graded dose response manner.

CONCLUSION

Greater adverse childhood experiences are associated with three landmarks of opioid use risk. ACE screening may be useful in identifying high-risk subsets of opioid-using populations.

Sex differences in prescription opioid use

PURPOSE OF REVIEW

Recent literature focused on prescription opioids has neglected sex differences in use. Here, we evaluated the recent literature (since 2015) examining sex differences in prescription opioid use.

RECENT FINDINGS

Between 2015 and 2016, our review found only eight articles addressing sex differences in prescription opioid use mostly opioid misuse in North America among individuals with chronic pain. Risk factors included depression, pain, and polydrug use. In addition to that review, we had the opportunity to further address sex differences in, and risk factors for, prescription opioid use through a community engagement program, HealthStreet. Among the sample (n = 8525, Mage = 43.7 years, 58.6% women), approximately half reported use of prescription opioids. Women were significantly more likely to report lifetime use (54.9 vs. 42.2%; P < 0.0001) and report cancer compared with men, yet, women with cancer had a significantly reduced risk of using opioids compared with men with cancer (odds ratio: 0.46; 95% confidence interval, 0.36-0.59).

SUMMARY

Only a few recently published studies analyzed sex differences related to prescription opioid use. Findings from the literature and our data suggest women are more likely to use prescription opioids compared with men. There is limited information on sex differences in opioid use risk factors and outcomes and more research in this area is warranted.

Estimating State Transitions for Opioid Use Disorders

AIM

The aim was to estimate transitions between periods in and out of treatment, incarceration, and legal supervision, for prescription opioid (PO) and heroin users.

METHODS

We captured all individuals admitted for the first time for publicly funded treatment for opioid use disorder (OUD) in California (2006 to 2010) with linked mortality and criminal justice data. We used Cox proportional hazards and competing risks models to assess the effect of primary PO use (v. heroin) on the hazard of transitioning among 5 states: (1) opioid detoxification treatment; (2) opioid agonist treatment (OAT); (3) legal supervision (probation or parole); (4) incarceration (jail or prison); and (5) out-of-treatment. Transitions were conditional on survival, and death was modeled as an absorbing state.

RESULTS

Both primary PO (n = 11,733) and heroin (n = 19,926) users spent most of their median 2.3 y of observation out of treatment. Primary PO users were significantly younger (median age 30 v. 34 y), and a higher percentage were female (43.1% v. 31.5%; P < 0.001), white (74.6% v. 63.1%; P < 0.001), and had completed high school (31.8% v. 18.9%; P < 0.001). When compared to primary heroin users, PO users had a higher hazard of transitioning from detoxification to OAT (Hazard Ratio (HR), 1.65; 95% CI, 1.54 to 1.77), and had a lower hazard of transitioning from out-of-treatment to either detoxification (0.75 [0.70, 0.81]) or OAT (0.90 [0.85, 0.96]).

CONCLUSION

Our findings can be applied directly in state transition modeling to improve the validity of health economic evaluations. Although PO users tended to remain in treatment for longer durations than heroin users, they also tended to remain out of treatment for longer after transitioning to an out-of-treatment state. Despite the proven effectiveness of time-unlimited treatment, individuals with OUD spend most of their time out of treatment.

Non-medical opioid use and sources of opioids among pregnant and non-pregnant reproductive-aged women

BACKGROUND

The morbidity and mortality burden of the US opioid epidemic falls heavily on reproductive-age women. Information on the patterns of and sources for non-medical use of prescription opioids among reproductive age women, including pregnant women, will inform public health and prevention efforts to mitigate the effects of the opioid epidemic. This study characterized non-medical use of prescription opioids among reproductive-age U.S. women, with a focus on pregnancy status.

METHODS

We used nationally-representative data from the National Survey of Drug Use and Health (2005-2014) to examine non-medical use (NMU) of prescription opioids in the past 30days among females ages 18-44 (N=154,179), distinguishing pregnant women (N=8069). We used multivariable logistic regression to describe reported sources of opioids, including opioids obtained from a doctor, friend or relative, dealer, or other source.

RESULTS

Nearly 1% of pregnant women and 2.3% of non-pregnant reproductive-age women reported opioid NMU in the past 30days. Forty-six percent of pregnant women identified a doctor as their source compared with 27.6% of non-pregnant women reporting NMU. Pregnant women reported a friend or relative as their source of opioids less frequently than non-pregnant women (53.8% versus 75.0%), and some pregnant and non-pregnant women acquired opioids from a dealer (14.6% and 10.6%).

CONCLUSION

Opioid NMU among reproductive-age women is a complex public health challenge affecting a vulnerable population. Pregnant women were more likely than non-pregnant women to list a doctor as their source of opioids for NMU, suggesting the need for targeted policies to address physician prescribing during pregnancy.

Gender and race/ethnic differences in the persistence of alcohol, drug, and poly-substance use disorders

AIMS

To examine gender and racial/ethnic differences in the effect of substance use disorder (SUD) type on SUD persistence.

METHODS

Data were provided by 1025 women and 1835 men from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) to examine whether gender and race/ethnicity (Non-Hispanic White, Black, Hispanic) moderate the effects of DSM-IV defined past-12 month SUD type (alcohol, drug, poly-substance) on SUD persistence at 3-year follow-up, controlling for covariates. Using gender-stratified weighted binary logistic regression, we examined predictors of SUD persistence, tested an SUD type by race/ethnicity interaction term, and calculated and conducted Bonferroni corrected pairwise comparisons of predicted probabilities.

RESULTS

SUD persistence rates at 3-year follow-up differed for SUD type by gender by race/ethnicity sub-group, and ranged from 31% to 81%. SUD persistence rates were consistently higher among poly-substance users; patterns were mixed in relation to gender and race/ethnicity. Among women, alcohol disordered Hispanics were less likely to persist than Whites. Among men, drug disordered Hispanics were less likely to persist than Whites. Also, Black men with an alcohol or drug use disorder were less likely to persist than Whites, but Black men with a poly-substance use disorder were more likely to persist than Hispanics.

CONCLUSIONS

The effect of SUD type on SUD persistence varies by race/ethnicity, and the nature of these relationships is different by gender. Such knowledge could inform tailoring of SUD screening and treatment programs, potentially increasing their impact.

Causes of death and expected years of life lost among treated opioid-dependent individuals in the United States and Taiwan

AIMS

This study compared the cause-specific standardized mortality ratios (SMRs) and expected years of life lost (EYLL) among opioid-dependent individuals in the United States and Taiwan.

METHODS

Survival data came from two cohorts followed until 2014: The U.S. data were based on a randomized trial of 1267 opioid-dependent participants enrolled between 2006 and 2009; the Taiwan data were from a study of 983 individuals that began in 2006, when opioid agonist treatment (OAT) was implemented in Taiwan. SMRs were calculated for each national cohort and compared. Kaplan-Meier estimation was performed on the survival data, then lifespans were extrapolated to 70 years (840 months) to estimate life expectancy using a semi-parametric method. EYLLs for both cohorts were estimated by subtracting their life expectancies from the age- and gender-matched referents within the general population of their respective country.

RESULTS

Compared with age- and gender-matched referents, the SMRs were 3.2 for the U.S. sample and 7.8 for the Taiwan sample; the EYLLs were 7.7 and 16.4 years, respectively. Half of decedents died of unnatural causes in both cohorts; overdose deaths predominated in the U.S. and suicide in Taiwan.

CONCLUSIONS

Our study identified differences by country in EYLL and causes of deaths. These findings suggest that intervention strategies to reduce mortality risk by overdose (particularly in the U.S.) and suicide (particularly in Taiwan) are urgently needed in these countries.

A Hazard Analysis of Risk Factors of Mortality in Individuals Who Inject Drugs in Denver CO

Despite multiple risk factors for mortality among People Who Inject Drugs (PWID), more research is warranted that examines sub-populations within PWID. Mortality data from PWID participating in longitudinal HIV prevention research in Denver were obtained from The Colorado Department of Public Health and Environment. Risk factors for both all-cause and acute-toxicity related mortality were analyzed using Cox proportional hazards regression. Two-thousand seven individuals were interviewed at baseline. Eighty-six individuals died during the time frame of the study, 58 of which were due to acute-toxicity. Disabled (HR = 3.3, p < 0.001), gay/lesbian-identified (HR = 2.6, p = 0.03), white race/ethnicity (HR = 2.4, p = 0.003), and use of a shared cooker (HR = 2.1, p = 0.01) were important adjusted risk factors. These suggest that drug and HIV interventions should utilize techniques that can address the needs of marginalized populations in addition to HIV drug risk behaviors.

Association between cannabis use and methadone maintenance treatment outcomes: an investigation into sex differences

Background

Cannabis will soon become legalized in Canada, and it is currently unclear how this will impact public health. Methadone maintenance treatment (MMT) is the most common pharmacological treatment for opioid use disorder (OUD), and despite its documented effectiveness, a large number of patients respond poorly and experience relapse to illicit opioids. Some studies implicate cannabis use as a risk factor for poor MMT response. Although it is well established that substance-use behaviors differ by sex, few of these studies have considered sex as a potential moderator. The current study aims to investigate sex differences in the association between cannabis use and illicit opioid use in a cohort of MMT patients.

Methods

This multicentre study recruited participants on MMT for OUD from Canadian Addiction Treatment Centre sites in Ontario, Canada. Sex differences in the association between any cannabis use and illicit opioid use were investigated using multivariable logistic regression. A secondary analysis was conducted to investigate the association with heaviness of cannabis use.

Results

The study included 414 men and 363 women with OUD receiving MMT. Cannabis use was significantly associated with illicit opioid use in women only (OR = 1.82, 95% CI 1.18, 2.82, p = 0.007). Heaviness of cannabis use was not associated with illicit opioid use in men or women.

Conclusions

This is the largest study to date examining the association between cannabis use and illicit opioid use. Cannabis use may be a sex-specific predictor of poor response to MMT, such that women are more likely to use illicit opioids if they also use cannabis during treatment. Women may show improved treatment outcomes if cannabis use is addressed during MMT.