Cannabis Cessation Research Articles

Abstinence phobia among adult African American/Black cannabis users

ObjectiveAfrican American/Black individuals experience significant health disparities, particularly as it relates to cannabis use. As such, there is a need to identify intrapersonal factors related to more severe patterns of use among this subpopulation. Worry about quitting or reducing cannabis as a result of the anticipated anxiety-related states during deprivation (i.e., abstinence phobia) is one factor that is theoretically important in the context of cannabis-related disparities. MethodThe current study sought to examine the cross-sectional association between abstinence phobia and cannabis use problems, perceived barriers for cannabis cessation, and cannabis withdrawal symptoms. Participants included 83 African American/Black cannabis users (31.3% female, Mage = 38.12, SD = 10.42). ResultsCannabis abstinence phobia was associated with greater severity of cannabis use problems, more perceived barriers for quitting cannabis use, and more severe cannabis withdrawal symptoms. ConclusionsAbstinence phobia may represent an underrecognized intervention target for addressing cannabis use problems and quit success.

Dual case study of continued use vs cessation of cannabis in psychosis: a theoretically informed approach to a hard problem

PurposeCannabis use in the context of psychosis has been shown to have a negative impact on prognosis and yet it is difficult to treat. Recent randomized controlled trials all have negative findings and novel approaches is sought after. This paper aims to use an embodied cognition framework to add to the understanding of cannabis use in psychosis.Design/methodology/approachThe paper presents longitudinal, qualitative data on two individuals diagnosed with schizophrenia and using cannabis at least twice weekly prior to inclusion in the study. Factors influencing cannabis use were mapped in dialogue with the participants. Each participant was interviewed six times over the course of a year. The analysis was informed theoretically to describe processes maintaining or ameliorating cannabis use over time.FindingsThis study shows that a systems approach for understanding changes in cannabis use is meaningful; the richness of observations add to the understanding of differences in outcomes. Findings suggest that reductions in cannabis use in psychosis could be dependent on synergistic effects between contextual conditions. Attending closer to the experience of patients may help inform future interventions. However, interventions focusing on single mechanisms may be futile, if an array of individual, formative experiences are a prerequisite for change. A systemic understanding of dual diagnosis calls for tailored, individualized interventions.Originality/valueThe research tests a novel systemic perspective on cannabis use in psychosis by applying it to qualitative longitudinal data. Adding a systemic perspective may help develop future interventions addressing cannabis use in psychosis, which has long been considered a “hard problem” in dual diagnosis treatment.

Medical cannabis use in Canadians with multiple sclerosis

Background: The extent of medical cannabis use by people with multiple sclerosis (MS) in Canada has not been evaluated for more than a decade since recreational cannabis was legalized. Legalization provided an avenue for those to whom legal cannabis was previously inaccessible to access it as an alternative therapy. Our objective was to evaluate the prevalence of medical cannabis use by Canadians with MS, the reasons it is used, adverse effects, as well as the context surrounding how it is obtained and where users learned about it. Methods: An anonymous questionnaire was distributed to prospective participants through various channels. The questionnaire included questions about participant characteristics and quality of life, their MS, and their medical cannabis use. It also employed two validated patient-reported outcome measures, the PDDS and the MSQOL-54. Results: Completed questionnaires were submitted by 344 individuals. Among respondents, 215/344 (64.5%) reported having used medical cannabis at least once, and 180 (52.3%) reported still currently using it. Based on disease and quality of life data, we found that respondents with more severe or progressive forms of MS were more likely to have tried medical cannabis. Medical cannabis was used most by current and former users to treat sleep problems (84.2%), pain (80.0%), and spasticity (68.4%), while the most reported adverse effects were drowsiness (57.2%), feeling quiet/subdued (48.8%), and difficulty concentrating (28.4%). Most current and former users obtained their cannabis from a legal, reliable source (76.1%) and many (74%) learned about medical cannabis from someone other than a healthcare provider. Conclusions: This study showed that nearly two-thirds of survey respondents, comprised of Canadians living with MS, have tried medical cannabis at least once and that those with a greater disease burden were more likely to have tried it. Users reported that cannabis is moderately to highly effective in treating several symptoms and that adverse effects are not generally severe, nor are they the main factor driving medical cannabis cessation. Our results support the need for more research examining medical cannabis use in MS and for evidence-based resources to be publicly available for those exploring it as a potential therapy.

Abstract 14284: "Weeding" Out Wellens' Syndrome

Introduction: Wellens’ syndrome, most often associated with proximal left anterior descending coronary artery stenosis, is considered highly specific for impending myocardial infarction (MI). Its diagnosis relies on symmetric biphasic or deeply inverted T waves in leads V1-V4, normal precordial R wave progression and normal to slightly elevated cardiac markers. Pseudo-Wellens’ syndrome presents similarly, but in the absence of coronary artery disease (CAD). We present a challenging case of a patient with history of excessive recreational cannabis use and incidental electrocardiogram (ECG) findings concerning for Wellens’ syndrome who ultimately was diagnosed with Pseudo-Wellens’ syndrome. With familiarity of cannabis associated Pseudo-Wellens’ syndrome, unnecessary invasive diagnostic and therapeutic procedures were avoided. Case: A 20 year old male without significant past medical history presented for evaluation of vomiting and abdominal pain of 2 days duration. In view of his daily cannabis use, he was diagnosed with cannabis hyperemesis syndrome. An ECG to measure QTc prior to administration of ondansetron demonstrated ST elevation in lead V2. A repeat ECG showed T-wave inversions in leads V2-4. Troponin levels were negative. The patient denied chest pain or shortness of breath. An echocardiogram showed normal cardiac wall motion and an estimated ejection fraction of 55-60%. The diagnosis of Pseudo-Wellens’ syndrome secondary to cannabis use was made and the patient was subsequently discharged home following extensive cannabis cessation counseling. Discussion: The definitive treatment of Wellens’ Syndrome relies on cardiac catheterization even in patients without cardiac history or risk factors for CAD. This immediate intervention is required to halt the evolution of MI and is crucial for a positive outcome. In contrast, Pseudo-Wellens’ syndrome occurs in the absence of CAD and has been reported in younger, healthy patients in association with illicit drug use. In the era of increased legalized marijuana use, it is imperative that health care providers are familiar with cannabis induced Pseudo-Wellens’ syndrome as to avoid the potential for inappropriate invasive diagnostic modalities in otherwise healthy individuals.

Assessment of Withdrawal, Mood, and Sleep Inventories After Monitored 3-Week Abstinence in Cannabis-Using Adolescents and Young Adults.

Introduction: Among adolescents and young adults, cannabis use is prevalent. Prior studies characterizing withdrawal effects in this age range have primarily included treatment seeking or comorbid psychiatric samples; these studies have identified several affected domains, especially sleep, mood, and anxiety. The present study compared a community (i.e., nontreatment seeking) sample of cannabis-using and control participants on mood, anxiety, sleep, and withdrawal inventories during the course of a monitored 3-week cannabis abstinence period. Materials and Methods: Seventy-nine adolescent and young adult participants (cannabis-using group=37 and control group=42) were recruited from the community to undergo 3 weeks of confirmed abstinence (i.e., urine and sweat patch toxicology) and completion of Cannabis Withdrawal Symptom Criteria, State-Trait Anxiety Inventory, Beck's Depression Inventory, and Pittsburgh Sleep Quality Index across the study period. Repeated measures and cross-sectional regressions were used to examine main effects of group and interactions with time (where appropriate), while accounting for recent alcohol use and cotinine levels. Results: Cannabis-using participants reported higher mood (p=0.006), overall withdrawal (p=0.009), and sleep-related withdrawal (p<0.001) symptoms across abstinence compared to controls. Overall withdrawal severity (p=0.04) and sleep-related withdrawal symptoms (p=0.02) demonstrated a quadratic trajectory across the monitored abstinence periods, with an increase from baseline and subsequent decreases in symptom severity. No differences of anxiety scores (p=0.07) or trajectories (p=0.18) were observed. By study completion, groups did not differ among sleep quality components (all p's>.05). Conclusions: These findings revealed that nontreatment-seeking cannabis-using adolescents and young adults reported heightened total withdrawal symptoms during a 3-week sustained abstinence period relative to controls. Cannabis-using participants demonstrated an increase in withdrawal symptom trajectory during the first week followed by decreased symptoms from weeks 2 to 3, which contrasts with prior linear decreases observed in cannabis-using adolescent and young adults. More mood symptoms were observed in the cannabis-using group even while excluding for comorbid psychopathologies-along with significantly more sleep problems during the abstinence period. Implications include the necessity to provide psychoeducation for recreational, nontreatment-seeking cannabis-using individuals about cannabis withdrawal, mood symptoms, and sleep quality difficulties when cannabis cessation is attempted, to improve likelihood of long-term sustained abstinence.

S2058 Three Rare Cases of Neuroendocrine Carcinoma of the Esophagus in a Rural Community

Introduction: The frequency of cannabis use has increased in the USA in the last few years. The prevalence of cannabis induced hyperemesis has also increased during this time. We present a case of presumed esophageal perforation in a patient with cannabis hyperemesis syndrome. Case Description/Methods: A 26 year old female with daily inhaled cannabis use presents with nausea, vomiting and epigastric pain for 3 weeks. She denies chest pain or fever. She has been told in the past that she has Cannabis Hyperemesis Syndrome. Typically, her bouts last for one week and her symptoms improve with hot showers. On initial physical exam she was in moderate distress and tachycardic with tenderness over the epigastrium. Her WBC count was elevated at 18.53. She was also COVID-19 positive. CT of the abdomen performed in the ED noted free air surrounding the distal esophagus consistent with pneumomediastinum concerning for esophageal rupture. She was managed conservatively with close monitoring for a presumed esophageal perforation with spontaneous closure. She was made NPO and started on IV antibiotics. Over the next 48 hours, she developed crepitus in her neck and chest wall. Repeat imaging confirmed progression of pneumomediastinum. 48 hours later, she underwent a water-soluble esophagram negative for perforation and her diet was advanced. She was counseled on cannabis cessation and provided community resources for rehabilitation and discharged. Discussion: Cannabis Hyperemesis Syndrome is a functional disorder marked by episodes of nausea and vomiting provoked by cannabis use. It is considered to be a variant of cyclical vomiting syndrome. These episodes of retching and vomiting can lead to complications including Mallory-Weiss tears and in rare cases esophageal rupture. The treatment for cannabis hyperemesis syndrome includes volume resuscitation, anti-emetics and cannabis cessation. Esophageal perforations often present a diagnostic challenge due to the variability in presentation. This patient was fortunate to present early. She remained clinically stable without evidence of systemic inflammation or pleural or peritoneal collections and therefore was able to be managed conservatively. With increasing legalization and popularity of cannabis use, it is important to recognize the potentially devastating complications of chronic marijuana use resulting in cannabinoid hyperemesis syndrome. Although esophageal perforation is rare, it has the potential for great morbidity.

Cannabinoid Hyperemesis Syndrome Survey and Genomic Investigation.

Background:Cannabinoid hyperemesis syndrome (CHS) is a diagnosis of exclusion with intractable nausea, cyclic vomiting, abdominal pain, and hot bathing behavior associated with ongoing tetrahydrocannabinol (THC) exposure. Increasing cannabis use may elevate CHS prevalence, exacerbating a public health issue with attendant costs and morbidity.Objective, Design, and Data Source:This study, the largest contemporaneous database, investigated genetic mutations underlying CHS. Patients with CHS diagnosis and ongoing symptoms were compared with current cannabis users lacking symptoms.Target Population:A screening questionnaire was posted online. Of 585 respondents, 205 qualified as the CHS pool and 54 as controls; a reduced pool of 28 patients and 12 controls ultimately completed genomic testing.Results:Patients and controls were high-frequency users of cannabis flower or concentrates (93%), using multiple grams/day of THC-predominant material. Among patients, 15.6% carried diagnoses of cannabis dependency or addiction, and 56.6% experienced withdrawal symptoms. About 87.7% of patients improved after cannabis cessation, most suffering recurrence rapidly after resumption. Findings in patients included mutations in genes COMT {odds ratio, 12 (95% confidence limit [CL], 1.3–88.1) p=0.012}, transient receptor potential vanilloid receptor 1 (TRPV1) (odds ratio, 5.8 [95% CL, 1.2–28.4] p=0.015), CYP2C9 (odds ratio, 7.8 [95% CL, 1.1–70.1] p=0.043), gene coding dopamine-2 receptor (DRD2) (odds ratio, 6.2 [95% CL, 1.1–34.7] p=0.031), and ATP-binding cassette transporter gene (ABCA1) (odds ratio, 8.4 [95% CL, 1.5–48.1] p=0.012).Limitations:Some participants were reluctant to undergo genetic testing; only 28 of 99 CHS patients who agreed to testing ultimately returned a kit.Conclusion:This is the largest patient cohort of CHS examined to date, and first to note associated mutations in genes affecting neurotransmitters, the endocannabinoid system, and the cytochrome P450 complex associated with cannabinoid metabolism. Although the sample size was smaller than desired, these preliminary findings may contribute to the growing body of knowledge, stimulate additional investigation, help elucidate the pathophysiology of CHS, and, ultimately, direct future treatment.

Association between preconception cannabis use and risk of postpartum depression: Findings from an Australian longitudinal cohort

Background and aimEvidence suggests a positive association between cannabis use and depression however whether preconception cannabis use is associated with postpartum depression (PPD) remains unknown. This study examined the association using a longitudinal design. MethodsParticipants were from the Australian Longitudinal Study on Women’s Health (cohort born in 1989−95), a sample broadly representative of similarly aged Australian women. The association of past year cannabis use at 3–15 months prior to pregnancy with PPD at ages 19–24 to 22–27 was examined in 516 women with 570 singleton live births. The associations of chronicity, recency, and initiation of cannabis use before pregnancy with PPD at ages 21–26 to 24–29 were investigated in 538 women with 590 singleton live births. PPD was ascertained from self-report of doctor diagnosis for each birth. Relative risk (RR) and 95 % confidence interval (CI) were used to calculate the associations of interest. ResultsCompared with no cannabis use, any past-year cannabis use at 3–15 months before pregnancy may be associated with an increased risk of PPD (1.50, 0.99−2.28). Compared with no cannabis use in the first three annual surveys before pregnancy, chronic use (a past year user in ≥ 2 surveys) was associated with an 80 % higher risk of incident PPD for births in the following 1–4 years (1.80, 1.22−2.68). Compared to never users at ages 20–25, former users who had no use within the past year had no increased risk; past year users had 73 % higher risk (1.73, 1.07−2.81); and past year users who initiated cannabis use at or after age 18 had twice the risk of incident PPD for births in the following 1–4 years (2.02, 1.17−3.49). ConclusionThis study provides evidence that preconception cannabis use is associated with increased risk of PPD. More studies are warranted to confirm this finding before cannabis cessation policies can be reinforced on reducing the risk of PPD.

Increasing Cannabis Use Is Associated With Poorer Cigarette Smoking Cessation Outcomes: Findings From the ITC Four Country Smoking and Vaping Surveys, 2016-2018.

Concurrent use of tobacco and cannabis may impede successful cigarette smoking cessation. This study examined whether changes in cannabis use frequency were associated with smoking cessation. Nationally representative samples of adult cigarette smokers from Canada (n = 1455), the United States (n = 892), England (n = 1416), and Australia (n = 717) were surveyed in 2016 and 2018. In each year, smokers reported how often they used cannabis in the previous 12 months. Reports were compared to determine whether cannabis use increased, remained unchanged, or decreased. Smoking cessation outcomes, measured in 2018, were (1) any attempt to quit in the previous year, (2) currently quit, and (3) currently quit for at least 6 months. Weighted multivariable logistic regression estimated the association between changes in cannabis use and cessation outcomes. Cigarette smokers who increased their frequency of cannabis use were significantly less likely to be currently quit than noncannabis-using smokers (adjusted odds ratio (aOR) = 0.52, 95% CI = 0.31% to 0.86%); they were also less likely to have quit for at least 6 months (aOR = 0.30; 95% CI = 0.15% to 0.62%). Smokers who increase their frequency of cannabis use have poorer smoking cessation outcomes compared to noncannabis-using smokers. It will be important to monitor the impact of cannabis legalization on patterns of cannabis use, and whether this influences cigarette smoking cessation rates. Cigarette smokers who start using cannabis may be less likely to quit cigarettes compared with smokers who do not use cannabis at all. If smokers who also use cannabis are more likely to continue smoking, it is important to monitor these trends and understand the impact, if any, on smoking cessation in jurisdictions that have legalized cannabis for nonmedical use.

Cannabinoid Hyperemesis Syndrome: The Missed Diagnosis

Cannabis is the most cultivated and abused illicit drug worldwide. Paradoxically to the antiemetic properties attributed to cannabis, a relatively new cannabinoid hyperemesis syndrome (CHS) started to be recognized and is characterized by cyclic vomiting that are interspaced by asymptomatic phases. We present a case of a 36‑year‑old woman who repeatedly presented to the emergency room with cyclic vomiting that alleviated with hot showers. She was a long‑term cannabis user and the diagnosis was only established several years later after the onset of symptoms. The diagnostic work up was unremarkable, and the only effective treatment was cannabis cessation. Hot bathing behavior is a key characteristic of this syndrome. CHS is a new clinical condition that should be considered in a setting of recurrent and intractable vomiting in patients with a history of cannabis use.

Reduction and Cessation of Alcohol, Cannabis, and Stimulant Use: Prospective Associations With Changes in Depressive Symptoms Across Two Cohort Studies of Sexual and Gender Minorities

Sexual and gender minorities (SGM) are at increased risk for substance use and depression. However, little research has examined the directionality of associations between substance use and depression in this high-risk population, and we are not aware of any to parse associations between depression and changes in the frequency of substance use versus substance use cessation. Such research can help to inform the development of future interventions to address health disparities affecting SGM. We used data from two longitudinal cohorts of SGM assigned male at birth (SGM-AMAB; N = 1,418) to examine associations between changes in frequency of alcohol, cannabis, and stimulant use and depressive symptoms. Multilevel models tested whether changes in substance use predicted changes in depressive symptoms and vice versa. Results indicate that when SGM-AMAB decreased their alcohol use or ceased alcohol, cannabis, or stimulant use, they experienced concurrent decreases in depressive symptoms. Only reducing stimulant use (not alcohol or cannabis use) was associated with decreases in depressive symptoms over the subsequent 6 months. Depressive symptoms did not prospectively predict cessation or reduction in the use of any substance. These findings suggest that clinical interventions targeting substance use may simultaneously reduce depressive symptoms and that reductions in alcohol use (even in the absence of cessation) may simultaneously benefit mental health among SGM-AMAB. The limited evidence of prospective effects over 6 months suggests that studies with shorter lags may be better equipped to examine the directionality of the association between depressive symptoms and substance use/reduction.

S1997 Spontaneous Pneumomediastinum Secondary to Cannabinoid Hyperemesis Syndrome

INTRODUCTION: Marijuana use has been infrequently identified as a potential risk factor for the development of spontaneous pneumomediastinum, a rare condition characterized by free air in the mediastinum not preceded by medical or surgical trauma. We present the case of cannabinoid hyperemesis syndrome causing spontaneous pneumomediastinum. CASE DESCRIPTION/METHODS: A 23-year-old female with a history of cannabinoid hyperemesis syndrome presented to the emergency room with a 3-day history of chest pain associated with nausea and multiple episodes of vomiting. She confirmed a three-year history of daily inhaled marijuana use. A CT Chest revealed extensive pneumomediastinum with air tracking along the left hilum/bronchovascular sheath of an unclear source with no radiographic evidence of chest trauma. The patient was admitted to the intensive care unit for continued management. Subsequent water-soluble contrast esophageal revealed findings consistent with pneumomediastinum and no evidence of esophageal perforation, hence Boerhaave’s syndrome was excluded. Given her recurring cyclic vomiting in the setting of cannabis the patient was diagnosed with cannabinoid hyperemesis syndrome (CHS) with spontaneous pneumomediastinum. The patient was managed conservatively, with complete recovery and extensively counseled on cannabis cessation. DISCUSSION: Inhaled marijuana use has been infrequently identified as a potential risk factor for the development of spontaneous pneumomediastinum. Spontaneous pneumomediastinum is a rare clinical entity defined as the presence of free air within the mediastinal structures in the absence of thoracic trauma, surgery, or medical procedure. It is a self-limiting condition resulting from alveolar rupture secondary to an acute increase in intrathoracic pressure subsequently leading to dissection of air along the bronchovascular sheath towards the mediastinum. The hypothesized pathophysiology of marijuana related pneumomediastinum is barotrauma occurring during breathing movements. SPM is managed conservatively with analgesia and treatment of the underlying etiology. Long term prognosis depends on the etiology of the SPM and involves lifestyle modification especially in the setting CHS. Diagnosis of a SPM can often be overlooked as its presenting symptoms remains non-specific. A comprehensive history should be obtained including a detailed history of tobacco and cannabinoid use in patients with intractable nausea and vomiting with a low threshold for chest imaging.Image 1.: Air within the mediastinal structures with no evidence of perforation.Image 2.: Water-soluble contrast esophagram with no evidence of contrast extravasation into the mediastinum.

Frequent Cannabis Use and Cessation of Injection of Opioids, Vancouver, Canada, 2005-2018.

Objectives. To evaluate the impact of frequent cannabis use on injection cessation and injection relapse among people who inject drugs (PWID).Methods. Three prospective cohorts of PWID from Vancouver, Canada, provided the data for these analyses. We used extended Cox regression analysis with time-updated covariates to analyze the association between cannabis use and injection cessation and injection relapse.Results. Between 2005 and 2018, at-least-daily cannabis use was associated with swifter rates of injection cessation (adjusted hazard ratio [AHR] = 1.16; 95% confidence interval [CI] = 1.03, 1.30). A subanalysis revealed that this association was only significant for opioid injection cessation (AHR = 1.26; 95% CI = 1.12, 1.41). At-least-daily cannabis use was not significantly associated with injection relapse (AHR = 1.08; 95% CI = 0.95, 1.23).Conclusions. We observed that at-least-daily cannabis use was associated with a 16% increase in the hazard rate of injection cessation, and this effect was restricted to the cessation of injection opioids. This finding is encouraging given the uncertainty surrounding the impact of cannabis policies on PWID during the ongoing opioid overdose crisis in many settings in the United States and Canada.

Impact of 2 Weeks of Monitored Abstinence on Cognition in Adolescent and Young Adult Cannabis Users.

Previous research suggests recovery from cannabis-related deficits in verbal learning and memory functioning after periods of cannabis abstinence in adolescents. Here, we examine how cannabis cessation affects cognitive performance over 2 weeks of monitored abstinence compared to controls in adolescents and young adults. Seventy-four participants (35 cannabis users) aged 16-26 ceased all cannabis, alcohol, and other illicit substance consumption for a 2-week period; abstinence was monitored via weekly urinalysis, breath, and sweat patch testing. Starting at baseline, participants completed weekly abbreviated neuropsychological batteries. Measures included tests of attention, inhibition, verbal working memory, and learning. Repeated measures assessed within and between subject effects for time and group status, while controlling for past year alcohol and nicotine use. Cannabis users showed increased performance compared to controls on sustained attention tasks after 2 weeks of cannabis use. Deficits in attention, but not verbal learning and memory, recovered after 2 weeks of monitored abstinence. This differs from previous literature, suggesting that other cognitive domains may show signs of recovery after periods of cannabis cessation in adolescents and young adults.

Cannabis cessation among youth: rates, patterns and academic outcomes in a large prospective cohort of Canadian high school students.

Following cannabis legalization in Canada, a better understanding of the prevalence of unprompted cannabis use reduction and subsequent effects on youth academic outcomes is needed to inform harm reduction and health promotion approaches. We analyzed a longitudinally linked sample (n = 91774) from the COMPASS prospective cohort study of Canadian high school students attending Grades 9-12 in Ontario and Alberta between 2013-2014 and 2016-2017. We investigated the prevalence of spontaneous cannabis use reduction and cessation between grade transitions (Grades 9-10, 10-11, 11-12) and the effect of cessation on academic achievement (current or recent math and English course marks) and rigour (usual homework completion and past-month truancy). Only 14.8% of cannabis users decreased their use between grades. Of these, two-thirds made only incremental downward changes, a pattern which held true for all three transitions. Cessation rates from daily and weekly use decreased every year. After cessation, students had better odds than continuing users (OR = 1.23, 95% CI: 1.03- 1.48) and worse odds than never-users (OR = 0.55, 95% CI: 0.31-0.97) for some subcategories of math performance. Students who quit cannabis universally improved class attendance (OR = 2.48, 95% CI: 1.93-3.19) and homework completion (OR = 2.32, 95% CI: 1.85-2.92) compared to continuing users. Increased academic rigour may underlie any improvements seen in academic performance after cannabis cessation. High school students who use cannabis likely need targeted support to facilitate reduction or cessation and subsequent academic recovery. This indicates that a school-based focus on cannabis harm reduction is justified.

A systematic review and Bayesian meta-analysis of interventions which target or assess co-use of tobacco and cannabis in single- or multi-substance interventions.

Tobacco and cannabis are commonly co-used, and evidence for the influence of co-use on quit outcomes for either substance is mixed. We sought to determine the efficacy of tobacco and/or cannabis use interventions delivered to co-users on cannabis and tobacco use outcomes. Systematic review with meta-analysis and narrative review, using five databases and author requests for co-use data. Controlled and uncontrolled intervention studies focusing on treatment of tobacco and/or cannabis use assessing use of both pre- and post-intervention were included. Prevention interventions were excluded. Bayesian meta-analysis was used across four outcome measures: risk ratio for tobacco and cannabis cessation post-intervention separately; standardized mean change for tobacco and cannabis reduction post-intervention separately. Narrative reporting of the same outcome measures in non-randomized clinical trials (non-RCTs) and quality assessment of all included studies were conducted. Twenty studies (12 RCTs and eight uncontrolled) were included. Bayesian meta-analysis with informative priors based on existing data of 11 RCTs (six single-substance, five multi-substance interventions) delivered to co-users (n=up to 1117) showed weak evidence for an effect on cannabis cessation [risk ratio (RR)=1.48, credibility interval (CrI)=0.92, 2.49, eight studies] and no clear effect on tobacco cessation (RR=1.10, CrI=0.68, 1.87, nine studies). Subgroup analysis suggested that multi-substance interventions might be more effective than cannabis-targeted interventions on cannabis cessation (RR=2.19, CrI=1.10, 4.36 versus RR=1.39, CrI=0.75, 2.74). A significant intervention effect was observed on cannabis reduction (RR=0.25, CrI=0.03, 0.45, nine studies) but not on tobacco reduction (RR=0.06, CrI=-0.11, 0.23, nine studies). Quality of evidence was moderate, although measurement of co-use and cannabis use requires standardization. Uncontrolled studies targeting both cannabis and tobacco use indicated feasibility and acceptability. Single and multi-substance interventions addressing tobacco and/or cannabis have not shown a clear effect on either tobacco or cannabis cessation and reduction among co-users. However, dual substance interventions targeting tobacco and cannabis appear feasible.

Can a Smartphone App for Cannabis Cessation Gain a Broader User Group than Traditional Treatment Services?

Background:Treatment demand for cannabis use disorders is increasing in Europe. Mobile phone– and internet-based interventions for cannabis users can possibly help meet the need. The purpose of this study was to examine whether a recently developed Norwegian Cannabis Cessation app reaches a broader or different user group compared to community-based Cannabis Cessation programs (CCP, Nordic abbreviation: HAP).Method:The app respondents (n = 148) were recruited through an online link in the app. A comparative sample (n = 102) was recruited in three municipally based CCPs in Norway. We examined whether app users differed from the CCP population in sociodemographics, substance use, mental health, and well-being.Result:The app group included more women than the CCP group (46% versus 26%, χ2 = 10.9, P = .001), but otherwise the groups were similar for sociodemographic variables. Severity of cannabis use did not differ between groups, but the app sample exhibited a higher depressiveness score on the Hopkins Symptom Checklist (mean difference, 0.24; 95% CI 0.04–0.44; P = .018) and lower perceived well-being (3.4 point lower score on the Outcome Rating Scale; 95% CI −5.7 to −1.2; P = .003). Well-being was negatively associated with being in the app group, being older, and having higher levels of mental distress, and was positively associated with the perceived ability to make changes (‘self-efficacy of quitting’).Conclusion:The higher proportion of women in the app group indicated that the app did capture an expanded segment of the cannabis-using population. The app can be an alternative for those who are not yet prepared to seek treatment in formal healthcare services. The high level of depressive symptoms and lower levels of well-being among the app respondents suggest that some app users might need additional support.

The use of cannabis and perceptions of its effect on fertility among infertility patients.

STUDY QUESTIONWhat is the prevalence of cannabis use and the perceptions of its impact on fertility among infertility patients?SUMMARY ANSWERA total of 13% of infertility patients used cannabis within the last year, and current usage is associated with patient perceptions of negative effects of cannabis on fertility and pregnancy.WHAT IS KNOWN ALREADYCannabis use is increasing among the general population and pregnant women, particularly in places where cannabis use is legal despite having known and potential negative effects on fertility and pregnancy.STUDY DESIGN, SIZE, DURATIONA cross-sectional patient survey study was performed between July 2017 and September 2017. Patients attending a university-affiliated hospital-based fertility clinic (n = 290) were invited to complete a written survey. Inclusion criteria were limited to the ability to read English. There were no exclusion criteria.PARTICIPANTS/MATERIALS, SETTING, METHODSOf the 290 patients approached, 270 (93%) agreed to participate. The questions covered demographics, cannabis usage, perceptions of the effect of cannabis on fertility and pregnancy, cessation of use due to infertility and personal history of disclosing cannabis use to healthcare providers (HCP).MAIN RESULTS AND THE ROLE OF CHANCEThe results showed that 13% of respondents disclosed use of cannabis in the past year (past year users) and 38% had not used cannabis in the past year but had previously used cannabis (>1 year users) while 49% had never used cannabis (never users). Baseline demographics were similar for the three groups, but across four measures of fertility and pregnancy health, past-year users perceived less of a negative effect compared to >1 year users, and never users (P values of 0.02, 0.03, 0.01, <0.001 for questions on pregnancy, offspring health, male fertility and female fertility, respectively). Of past year users, 72% said they had or would disclose use to their HCP, but only 9.4% reported that their HCP had actually instructed them to discontinue use.LIMITATIONS, REASONS FOR CAUTIONSelf-reported patient surveys are subject to reporting bias and may not reflect actual use and perceptions.WIDER IMPLICATIONS OF THE FINDINGSThis study suggests that cannabis use is common among infertility patients. Given the known negative impacts of cannabis on pregnancy, the authors would have expected informed infertility patients to cease cannabis use as part of their efforts to conceive. As the prevalence of cannabis use in the last year among infertility patients is similar to that in the general Canadian population, it is unclear whether the prevalence of cannabis use in the sample population merely reflects the average usage in society or, after taking into account those who reduced their usage to improve their fertility, is a factor contributing to infertility and thus prompting fertility referral. Given concern about the potential negative impact of cannabis use on fertility, and that only 9% of past year users had been instructed by an HCP to cease cannabis use, HCPs should consider the benefits of counselling about cannabis cessation for patients who are attempting to conceive. Future research should focus on analysing the effects of cannabis use on female fertility and determining whether a reduction in use among patients with infertility can improve conception rates.STUDY FUNDING/COMPETING INTEREST(S)Michelle Shin, Clinical Research Associate, is supported by the University of Toronto GREI Fellowship Fund, which is sponsored by unrestricted research grants from EMD Serono, Merck Canada and Ferring Pharmaceuticals. The authors have no potential conflicts of interest to disclose.

P.744 Is N-acetylcysteine a promising pharmacological treatment for cannabis and cocaine cessation?

Little is known about the health and health-care patterns of patients with diabetes according to their estimated glomerular filtration rates, especially within a publicly funded health-care system.Using linked health-care databases in Ontario, Canada, we performed a population-based study of adults 50 years of age and older (mean age, 68 years) with prevalent diabetes on January 1, 2014. We categorized patients according to their levels of kidney function (estimated glomerular filtration rate ≥90, 60 to 89, 30 to 59, 15 to 29 or <15 mL/min/1.73 m2, or the receipt of ongoing maintenance dialysis). We then followed patients for 2 years to determine: 1) their level of contact with health-care providers (i.e. visits to family doctors, specialists); 2) their use and repeated use of acute medical services (i.e. hospitalizations and emergency department encounters; 3) diabetes-related monitoring and screening (i.e. glycated hemoglobin and cholesterol tests, vision screening); 4) glycemic and lipid control; and 5) diabetes-related outcomes.There were 569,384 patients in our study. Most had estimated glomerular filtration rates between 60 and 89 mL/min/1.73 m2. At baseline, patients with lower kidney function had longer durations of diabetes and more comorbidities. Over 2 years of follow up, they had higher burdens of medical care, excessive diabetes monitoring and were underscreened for diabetes-related complications. Although metabolic control was reasonable across groups, patients with low kidney function had more hospital encounters and more diabetes-related complications.Patients with diabetes and low kidney function are a vulnerable population that faces health system challenges and care gaps. Suggestions for policy and practice are discussed.On en connaît peu sur les profils de santé et de soins de santé des patients diabétiques pour ce qui est de l'estimation des débits de filtration glomérulaire, notamment dans le système public de soins de santé.À partir des banques de données liées des soins de santé de l'Ontario, au Canada, nous avons réalisé une étude de population auprès d'adultes de 50 ans et plus (âge moyen, 68 ans) atteints de diabète le 1er janvier 2014. Nous avons réparti les patients selon leur niveau de fonctionnement rénal (estimation du débit de filtration glomérulaire≥90, de 60 à 89, de 30 à 59, de 15 à 29 ou<15 ml/min/1,73 m2, ou l'administration continue d'une dialyse d'entretien). Nous avons ensuite suivi les patients durant 2 ans pour déterminer : 1) leur fréquence de contact avec les prestataires de soins de santé (c.–à–d. les rendez-vous chez les médecins de famille et les spécialistes); 2) leur utilisation et leur utilisation récurrente des services de soins médicaux aigus (c.–à–d. les hospitalisations et les rendez-vous au service des urgences; 3) la surveillance et le dépistage du diabète (c.–à–d. les analyses de l'hémoglobine glyquée et du cholestérol, le dépistage des troubles de la vue); 4) la régulation du métabolisme des glucides et des lipides; 5) les résultats liés au diabète.Notre étude regroupait 569 384 patients. L'estimation des débits de filtration glomérulaire se situait entre 60 et 89 ml/min/1,73 m2 chez la plupart des patients. Au début, les patients qui montraient une diminution du fonctionnement des reins avaient un diabète depuis plus longtemps et plus de maladies associées. Pendant les 2 années de suivi, ils portaient un fardeau de soins médicaux plus lourd et démontraient une surveillance excessive de leur diabète, en plus de subir un sous-dépistage des complications liées au diabète. Bien que tous les groupes aient montré une régulation satisfaisante du métabolisme, les patients qui accusaient une diminution du fonctionnement rénal avaient plus de consultations à l'hôpital et plus de complications liées au diabète.Les patients diabétiques dont le fonctionnement rénal est diminué constituent une population vulnérable qui fait face aux enjeux du système de soins de santé et aux lacunes en matière de soins. Des suggestions de politiques et de pratiques font l'objet de discussions.

Depressive symptoms and cannabis use in a placebo-controlled trial of N-Acetylcysteine for adult cannabis use disorder.

Depression is common among individuals with cannabis use disorder (CUD), particularly individuals who present to CUD treatment. Treatments that consider this comorbidity are essential. The goal of this secondary analysis was to examine whether N-acetylcysteine (NAC) reduced depressive symptoms among adults (age 18-50) with CUD (N = 302) and whether the effect of NAC on cannabis cessation varied as a result of baseline levels of depression. Bidirectional associations between cannabis use amount and depression were also examined. Data for this secondary analysis were from a National Drug Abuse Treatment Clinical Trials Network (NIDA CTN) multi-site clinical trial for CUD. Adults with CUD (N = 302) were randomized to receive 2400mg of NAC daily or matched placebo for 12weeks. All participants received abstinence-based contingency management. Cannabis quantity was measured by self-report, and weekly urinary cannabinoid levels (11-nor-9-carboxy-Δ9-tetrahydrocannabinol) confirmed abstinence. Depressive symptoms were measured by the Hospital Anxiety and Depression Scale. Depressive symptoms did not differ between the NAC and placebo groups during treatment. There was no significant interaction between treatment and baseline depression predicting cannabis abstinence during treatment. Higher baseline depression was associated with decreased abstinence throughout treatment and a significant gender interaction suggested that this may be particularly true for females. Cross-lagged panel models suggested that depressive symptoms preceded increased cannabis use amounts (in grams) during the subsequent month. The reverse pathway was not significant (i.e., greater cannabis use preceding depressive symptoms). Results from this study suggest that depression may be a risk factor for poor CUD treatment outcome and therefore should be addressed in the context of treatment. However, results do not support the use of NAC to concurrently treat co-occurring depressive symptoms and CUD in adults. Clinicaltrials.gov: NCT01675661.