Contexte et objectifs: En 2018, le Canada légalisait la consommation de cannabis non médicale dans une perspective de protection de la santé publique. Au Québec, la vente légale de cannabis a été autorisée strictement dans le cadre d’un monopole public de succursales en ligne ou en personne (c.-à-d. la Société québécoise du cannabis – SQDC). Bien que la plupart des consommateurs ne subissent pas ou très peu d’impact négatif résultant de leur consommation, il existe certains risques et méfaits associés à la consommation aiguë ou chronique de cannabis pour la santé mentale et physique, et ce, en particulier chez des populations vulnérables. Plusieurs indicateurs-clés de vulnérabilité liées aux méfaits et aux risques de l’utilisation de cannabis ont été identifiés dans la littérature scientifique, par exemple ceux liés au profil d’utilisation, aux motifs de consommation et à la présence de comorbidités. Différents risques sont associés à l’approvisionnement illégal ou non contrôlé, notamment quant à la teneur et à l’impureté des substances illicites, et à l’exposition à des environnements criminels. La mise en place d’un réseau de distribution réglementé vise à encadrer la vente de cannabis afin de diminuer et prévenir les risques liés à la consommation. Afin d’atteindre les objectifs de santé publique visés, il sera nécessaire de tenir compte des de la réduction des méfaits particulièrement chez les individus vulnérables mais, également de mettre en place des plan de suivis de la consommation de cannabis et de ses impacts sur la santé des populations. Très peu d’informations sont actuellement disponibles au sujet des sources d’approvisionnement utilisées par les consommateurs et leurs possibles associations avec les indicateurs de vulnérabilité. L’objectif de cette étude est d’offrir une description populationnelle des consommateurs de cannabis en fonction de la source d'approvisionnement et d’explorer si l’approvisionnement est associé à des indicateurs clés de vulnérabilité aux méfaits et aux risques liés à cette substance. Méthode et démarche: Cette étude consiste en une analyse secondaire des résultats de l'Enquête québécoise sur le cannabis (EQC), une enquête populationnelle transversale menée auprès de Québécois (>15 ans, n=10,192) entre le 11 février et le 9 juin 2019. L’échantillon de recherche a été limité aux consommateurs majeurs ayant accepté de déclarer les sources d’approvisionnement utilisées (n=1799). Des poids populationnels ont été utilisés afin d’offrir des estimations représentatives de la population québécoise entière. Des régressions logistiques binaires ajustées incorporant les poids populationnels (appelés ‘bootstrap’) ont été utilisées afin d’estimer l’association entre l’approvisionnement en cannabis auprès de succursales réglementées (SQDC), comparativement à l’approvisionnement auprès d’autres sources, et sept indicateurs de vulnérabilité (c.-à-d. la consommation problématique, la fréquence de consommation, la détresse psychologique, la conduite automobile avec facultés affaiblies, la co-utilisation d’autres substances, le contenu du cannabis en cannabinoïdes ainsi que les motifs de consommation). Tous les modèles statistiques ont été ajustés pour les variables confondantes identifiées tel l’âge, le sexe et le statut socio-économique. Résultats et outil développés : Au cours de l’année précédant l’enquête de 2019, 47,8% des consommateurs québécois se sont approvisionnés auprès de la SQDC et 52,2% auprès d’autres sources. Les profils de vulnérabilité des consommateurs ne s’étant pas procuré le cannabis auprès de la SQDC, comparativement aux profils des consommateurs s’étant approvisionné à la SQDC, étaient similaires sur le plan de la détresse psychologique (rapport de cotes ajusté [RCA]=0,99; Intervalle de confiance [IC]=0,26-3,79; p=0,991), des comportements à risque reliés à la conduite automobile (RCA=0,93; IC=0,26-3.36; p=0,984), de la co-utilisation d’autres substances (RCA=0.80; IC=0,14-4.75; p=0,806), du risque de consommation problématique (RCA=0,46; IC=0,13-1,64; p=0,230), des motifs de consommation pour gérer les affects négatifs (RCA=0,62; IC=0,16-2,46; p=0,499) et de la fréquence de consommation (RCA=0,46; IC=0,12-1,67; p=0,238). Cependant, les consommateurs ne s’étant pas approvisionné à la SQDC présentaient un risque plus élevé d’ignorer le contenu en cannabinoïdes des produits consommés (RCA=4,12; IC=1,10-15,40; p=0,035). Conclusion et recommandations : La vulnérabilité aux méfaits reliés à l’utilisation du cannabis semble similaire entre les consommateurs s’approvisionnant à la SQDC et ceux s’approvisionnant d’autres sources. Cependant, les consommateurs de la SQDC connaissaient mieux le contenu en cannabinoïdes des produits achetés que les autres consommateurs. Il reste à déterminer si cette connaissance se traduit par une réduction des conséquences négatives liées à la consommation. / Background: In 2018, Canada legalized the recreational use of cannabis to reorient consumers to a new legal market. In Quebec, “the Société Québécoise du Cannabis” (SQDC) was created to manage cannabis sales with a focus on public health protection by offering controlled product, reaching a growing number of consumers. However, a significant proportion of them still purchase cannabis from other sources. It remains unknown how the cannabis supply source of consumers affects their vulnerability profile to cannabis-related harms. Objectives: To compare the vulnerability profile of consumers buying their cannabis from the SQDC with those getting their cannabis elsewhere. Methods: We used data from a cross-sectional, representative population survey (>15 years, n=10,192), the Enquête Québécoise sur le Cannabis, which was completed between February and June 2019. The research sample was limited to adult consumers who agreed to declare the sources of supply used (n=1799). Population weights were used to provide estimates representative of the entire Quebec population. We used adjusted binary logistic regressions, incorporating population weights, to assess seven indicators of vulnerability related to the risk of cannabis harms. Results: The profile of vulnerability of SQDC users (47.8%) and those purchasing their cannabis elsewhere (52.2%) was similar in terms of mental health distress (Adjusted odd ratio (AOR)=.99; CI=0.26-3.79), drug-impaired driving behaviors (AOR=0.93; CI=0.26-3.36), co-consumption of other substances (AOR=0.80; CI=.14-4.75), risk of problematic cannabis use (AOR=.46; CI=.13-1.64), use to cope (OR=.62; CI=.16-2.46) and frequency of cannabis use (AOR=.46; CI=.12-1.67). However, SQDC users were more likely to be aware of the cannabinoid content of the product purchased compared to other users (AOR=4.12; CI=1.10-15.40). Conclusion: Vulnerability profiles to cannabis related harms appeared similar between consumers purchasing at the SQDC and those purchasing elsewhere, but SQDC consumers were more aware of the cannabinoid content of the products purchased. Whether this knowledge translates into a reduction in the negative consequences related to consumption is still to be determined. Overall, this can also suggest that at-risk cannabis users are reached by the legal cannabis supply source in Quebec.

The purpose of this integrative literature review was to understand the effects of medical cannabis for chronic pain management in adults. Anecdotal reports suggest the use of medical marijuana as a pain management therapy could be an alternative to opioids and other medications which have long term consequences. Potential uses span the health care continuum, from prescribed outpatient symptom management, to acute care, extended care, home care, and hospice treatment settings. The methodology included a review and synthesis of relevant research articles from 2012 to 2018, written in the English language. The findings suggest medical cannabis has the potential of effectively managing chronic pain in older adults. Adverse effects, if present, are mild and resolve without intervention. Lower doses of medical cannabis were reported to be more effective in treating chronic pain compared to higher doses. Inconsistencies in the efficacy of THC were noted compared to CBD for managing neuropathic pain. Implication for nursing practice, policy, education, and recommendation for future research were discussed along with study limitations.

Posttraumatic stress disorder (PTSD) and substance use disorder (SUD) frequently co-occur. Comorbid PTSD+SUD confers heightened risk of other mental health concerns, suicidality, mortality, and functional impairment. Current treatments for comorbid PTSD+SUD show inconsistent results, highlighting the need for a more comprehensive understanding of the associations between PTSD and SUD symptoms. The current dissertation aimed to characterize the associations between PTSD and SUD using structural equation modelling among three different samples with differing clinical severity and presentation: (1) concurrent disorders sample with a high prevalence of PTSD; (2) an in-patient sample seeking treatment for PTSD; and (3) a subclinical sample of healthcare workers and public safety personnel. Data were extracted from multiple clinical databases across different studies to evaluate the associations between PTSD symptoms and alcohol/cannabis/substance use-related problems. Furthermore, the role of underlying mechanisms such as dissociation and emotion dysregulation, which are associated with both PTSD and SUD, were analyzed. All analyses used a structural equation modelling framework to represent the complex clinical presentation of comorbid PTSD+SUD analytically. A relatively consistent pattern of results was observed across the three samples. Global PTSD symptoms were significantly associated with cannabis-related problems, alcohol-related problems, and other illicit substance-related problems. Among PTSD symptoms, the reactivity symptom cluster (characterized by symptoms of hypervigilance, irritability, reckless behaviour, problems with concentration and sleep disturbances) was significantly associated with alcohol/cannabis/substance-related v problems across among the three samples. Furthermore, underlying mechanisms such as dissociation and emotion dysregulation significantly mediated the relations between PTSD symptoms and alcohol/cannabis/substance-related problems. Overall, the current results contribute to the limited literature examining the associations between PTSD and SUD symptoms. Lastly, the current results have important clinical implications for identifying efficacious treatment targets for comorbid PTSD+SUD. / Dissertation / Doctor of Philosophy (PhD) / Psychological distress following a traumatic event, known as traumatic stress, is often associated with problematic alcohol and/or substance use. The co-occurrence of these two confers a heightened risk of other mental health problems. As such, studying how these phenomena are associated with one another and what about each thing is more important to the association is important to understand. The purpose was to examine the connection between these phenomena among three different groups of people: two treatment-seeking groups and non-treatment seeking group one group. Traumatic stress was associated with problematic substance use in all three groups. In addition, other factors like mentally escaping from your body and having difficulties with regulating your emotions explained how traumatic stress and problematic substance use were connected to each other. These findings can help clinicians hone their treatment programs to better help individuals struggling with traumatic stress and problematic substance use.

No description available.

Background: Cannabis use is highly prevalent among adolescents in Germany, and chronic cannabis use (CCU) during this developmental stage raises significant public health concerns due to its potential impact on neurodevelopment. Adolescents with CCU are at a major risk of developing Cannabis use Disorder (CUD), particularly when co-occurring psychiatric disorders are present, which can negatively affect treatment outcomes for CUD. Among these co-occurring disorders, psychotic and depressive disorders have frequently been associated with adolescent CCU. Moreover, CCU in adolescence is associated with cognitive impairment, with impaired verbal learning ability being a common manifestation. These cognitive impairments and co-occurring disorders are rooted in underlying neurobiological alterations that may disrupt normal brain development during adolescence. The psychoactive effects of cannabis primarily stem from Δ⁹-trans-Tetrahydrocannabinol, and it is suspected that cannabis use affects the signaling of the endocannabinoid system (ECS). The ECS, known for its regulatory role in various physiological systems such as stress and immune responses, has been implicated in the neurobiological processes underlying certain psychiatric disorders. In recent years, there has been a growing interest in understanding the factors contributing to neurobiological changes associated with psychiatric disorders. Epigenetic processes, which describe the interplay between environmental factors and genetic regulation of phenotypic expression, have gained particular attention. DNA methylation (DNAm), the most extensively studied epigenetic mechanism, has emerged as a central focus in identifying epigenetic changes that underlie the neurobiological processes involved in psychiatric disorders. The present dissertation aims to investigate the psychological, neurobiological, and epigenetic correlates associated with CCU in adolescent outpatients with CUD. By exploring these dimensions, this work seeks to enhance our understanding of the multifaceted factors contributing to CCU and its impact on adolescent mental health. Methods: This thesis consists of five studies presented in chapters 2 to 6. Chapter 2 provides a description of the sample of adolescent outpatients who sought treatment at the SUD outpatient center. The chapter focuses on the prevalence of cannabis and other substance use, the occurrence of cannabis and other substance use disorders (SUDs), and the presence of co-occurring psychiatric disorders. In chapter 3, a study examines the association between cannabis use, additional 3,4-methylenedioxymethamphetamine (MDMA) use and attenuated psychotic symptoms (APS). Chapter 4 presents a study that investigates the relationship between CCU and DNAm. Additionally, it explores the potential mediating effects of DNAm on the association between CCU and impaired cognitive performance. The focus of chapter 5 is on the relationship between depressive symptoms and DNAm in target genes related to depression. The study also examines the association between DNAm of depression-related genes and CCU, while exploring the mediating effects of DNAm on the relationship between CCU and depressive symptoms. Finally, in chapter 6, a study analyzes site-specific DNAm to estimate the proportions of circulating white blood cell types in adolescents with CCU compared to non-using controls (NCU). The study also investigates the DNAm profiles of selected immune cell markers and determines their gene expression levels. Results: In a first step, the prevalence of cannabis use and CUD among treatment seeking adolescents with suspected SUD was examined. Cannabis use and CUD was highly prevalent in the sample. The results indicated no effects of gender or age on cannabis use and CUD prevalence rates. Further, co-occurring conduct disorders, attention deficit hyperactivity disorders and depressive disorder were also highly prevalent in this sample. In chapter 3, the results did not indicate a relationship between APS and cannabis use, which was contrary to the predictions. MDMA use additional to cannabis however was associated with increased APS. However, as described in Chapter 4, CCU was associated with impairment in a verbal learning task. Furthermore, six CpG sites were identified whose DNAm levels showed a significant mediating effect on the relationship between CCU and verbal learning impairment. The results presented in Chapter 5 indicate that CCU is associated with increased depressive symptoms, and both depressive symptoms and CCU are associated with DNAm of one key gene in the stress system. Moreover, the findings in the last chapter, Chapter 6, suggest that CCU has immune-modulatory effects and affects the proportion of B-cells in adolescents with CCU, potentially acting through the alteration of DNAm of related genes. Discussion: The studies conducted in this thesis have produced several significant findings. Firstly, it was observed that cannabis use and CUD are highly prevalent among adolescents with SUDs. While there was no cross-sectional association between cannabis use and increased APS, it was associated with higher levels of depressive symptoms, poorer performance in verbal learning tasks, and a higher prevalence of co-occurring psychiatric disorders. Additionally, it was found that adolescent CCU may have an impact on the epigenome through alterations in DNAm. Specifically, these alterations may affect the regulation of cognitive processes by influencing neurogenerative processes. Adolescent CCU may also interfere with the stress axis through DNAm-related changes. Furthermore, there is evidence to suggest that adolescent CCU may impair parts of the immune system. However, it is important to note that the studies presented in this thesis are based on cross-sectional data, and therefore, causal interpretations cannot be made. The relationships discussed, which imply causality, are speculative and require examination in longitudinal studies.:Statement for a publication-based dissertation List of Tables List of Figures Important Abbreviations Abstract 1. General Introduction 1.1 Prevalence of Cannabis Use and Cannabis Use Disorder (CUD) 1.2 CCU associated cognitive and behavioral changes 1.3 Neurobiological changes associated with CCU in adolescence 1.4. Epigenetic regulations and DNA methylation 1.5 Research Aims and Hypotheses 1.6 Sample Population and Measurements 2. Prevalence of cannabis use and CUD in an outpatient clinic 2.1 Background 2.2 Methods 2.3 Results 2.4 Discussion 2.5 Conclusion 2.6 Acknowledgements, Funding, Conflicts of Interest 3. Cannabis use and psychotic symptoms 3.1 Background 3.2 Methods 3.3 Results 3.4 Discussion 3.5 Conclusion 3.6 Acknowledgements, Funding, Conflicts of Interest 4. CCU, cognitive impairment and shared epigenetic associations 4.1 Background 4.2 Methods 4.3 Results 4.4 Discussion 4.5 Conclusion 4.6 Acknowledgements, Funding, Conflicts of Interest 5. CCU, depressive symptoms and shared epigenetic associations 5.1 Background 5.2 Methods 5.3 Results 5.4 Discussion 5.5 Conclusion 5.6 Acknowledgements, Funding, Conflicts of Interest 6. Immunological alterations associated with CCU 6.1 Background 6.2 Methods 6.3 Results 6.4 Discussion 6.5 Conclusion 6.6 Acknowledgements, Funding, Conflicts of Interest 7. General Discussion 7.1 Summary 7.2. Implications for DNAm mediated disruption of cognitive systems due to adolescent CCU 7.3 Implications for DNAm mediated disruption of immunological systems and its interactions with depression in chronic cannabis users 7.4 Neurobiological and epigenetic alteration may be affected by CCU 7.5. Clinical Implications 7.6. Limitations & Future Research 8. References 9. Appendices 9.1 Appendix A (chapter 2) 9.2 Appendix B (chapter 3) 9.3 Appendix C (chapter 4) 9.4 Appendix D (chapter 5) 9.5 Appendix E (chapter 6) 10. Erklärung gemäß der Promotionsordnung

Background: Canada continues to face an opioid epidemic with 5,368 opioid apparent related deaths occurring between January and September of 2021. Methadone Maintenance Treatment (MMT), a form of Medication Assisted Treatment used to treat Opioid Use Disorder (OUD), has been reported to decrease opioid cravings and opioid use, however, individual differences exist in the effective dose of methadone. Further, individuals living with an OUD have higher rates of substance use including cannabis. A genetic component has been suggested to exist for both cannabis use and MMT outcomes, however inconsistent findings have been reported. Methods: Knowledge synthesis and primary genetic association studies were conducted. A protocol was prepared for the planning of a systematic review for Genome-Wide Association Studies (GWASs) of cannabis use. The full systematic review was then conducted, providing an assessment of the literature and a description of studies quality. A GWAS and Polygenic Risk Score (PRS) was then conducted for cannabis use and MMT outcomes, separately, in Europeans only. The top Single Nucleotide Polymorphisms (SNPs) were then analyzed separately by sex and sex interactions were conducted. Results: The systematic review included 6 studies, identifying 96 genetic variants associated with cannabis use. The GWASs for both cannabis use and MMT outcomes did not identify any significant results. A significant PRS was found for regular cannabis use and methadone dose. No sex-specific results were identified. Discussion: This thesis summarised the evidence on the genetics of cannabis use as well as employed GWASs and PRSs to investigate cannabis use and MMT outcomes within a European population. We were able to highlight gaps within the genetic literature of cannabis and MMT outcomes as well as identify areas of interest for future research. / Dissertation / Doctor of Philosophy (PhD) / Cannabis use rates in Canada are increasing, with Opioid Use Disorder (OUD) patients having high rates of cannabis use despite inconsistent findings on the impacts. To combat the opioid crisis, Methadone Maintenance Treatment (MMT) is utilized to reduce opioid cravings and use. However, individuals on MMT are likely to use other substances, including cannabis. This thesis explores the genetic literature on cannabis use and conducts a Genome-Wide Association Study (GWAS) and a Polygenetic Risk Score (PRS). The GWAS investigates genetic variants throughout the whole genome associated with a trait, while the PRS creates a genetic weight risk score. GWAS and PRS methods were used to investigate cannabis use and MMT outcomes within Europeans with OUD. While no significant GWAS results were found, a statistically significant PRS was found for regular cannabis use and methadone dose, suggesting each respective score can estimate an individual’s risk of that trait.

Background With the impending legalization of recreational cannabis in Canada, it is important to examine the strength of association between cannabis use and common mental health concerns including depression, anxiety, and suicide and the extent to which these associations have changed over time. It is also important to examine the moderating effects of developmental age and biological sex on these associations. Methods This study uses Statistics Canada data from the 2002 and 2012 Canadian Community Health Survey’s Mental Health Component (CCHS-MH) which represent repeated cross-sectional surveys from nationally representative samples of Canadians 15 years of age and older (2002 n=36,984; 2012 n=25,113). Stepwise multivariate analyses were performed using linear regression for psychological distress and binary logistic regression for Major Depressive Episode (MDE) and suicidal thoughts and attempts. Time was accounted for as a binary indicator (2002 vs. 2012) and an interaction term between cannabis use and time was added to all the models. Additional interaction terms were added to the models to test the moderating effects of cannabis frequency, developmental age, and biological sex. Sensitivity analyses were performed to adjust for other substance use and socioeconomic covariates. Weighting and bootstrapping was utilized to present results reflective of the Canadian population. Results Cannabis use was positively associated with emotional problems, and this association strengthened over time, particularly for depression and suicidal thoughts and attempts. These temporal associations were similar across age groups and for males and females, and remained after controlling for other substance use and socioeconomic status. Conclusions Findings provide a baseline assessment of the Canadian population prior to legalization and direction for health promotion and prevention campaigns. Results highlight the need for awareness and regular monitoring of the cooccurrence of cannabis use and emotional problems and offer guidance for future research. / Thesis / Master of Health Sciences (MSc) / Using Statistics Canada data from the 2002 and 2012 Canadian Community Health Survey’s Mental Health Component, this dissertation determines the strength of association between cannabis use and common mental health concerns including depression, anxiety, and suicide and the extent to which these associations have changed over time. Cannabis use was positively associated with emotional problems, and this association strengthened over time, particularly for depression and suicidal thoughts and attempts. These temporal associations were similar across age groups and for males and females, and remained after controlling for other substance use and socioeconomic status. These results add novel insights to the existing literature about the changing relationship between cannabis use and emotional problems over time and potential mechanisms of this change are discussed. Given the impending legalization of recreational cannabis in Canada, clinical and research implications of results are discussed at length.

Introduction: The homeostatic role of the endocannabinoid system (ECS) is mediated through the actions of endocannabinoids. Intake of exogenous cannabinoids found in Cannabis sativa alter the function of the ECS which may then impact other organ systems. Use of cannabis has been inconsistently linked to adverse cardiometabolic outcomes. Rates of cannabis use are high among patients with psychiatric conditions who are already at higher risk of cardiometabolic diseases when compared to the general population. Cannabis use patterns and cardiometabolic risk variables in this population need further study to clarify the links between use and outcomes. Methods: Patients with psychiatric conditions from the St. Joseph’s Healthcare Hamilton Hospital were enrolled into the Cannabis and Physical Health study. Sociodemographic data, medical history, cigarette use, and cannabis use patterns were collected. In addition, cardiometabolic profile data were collected including body mass index, blood pressure, lipids, and HbA1c. Multivariable regression analyses were conducted, and a Bonferroni correction applied. Results: This cross-sectional study enrolled 200 patients (female: n=86, 43.0%), 18 years of age and older. Among 79 cannabis users (female: n=34, 43.0%), the majority (n=53, 67.1%) consumed cannabis daily and had a diagnosis of a moderate cannabis use disorder (CUD; n=57, 72.2%, CUD score = 4.3 ± 3.4). Use of cannabis was initiated on average at 15.2 ± 3.5 years of age and used for an average of 13.5 ± 11.0 years. There was no association between cannabis use and cardiometabolic risk factors when adjusted for age, sex, psychiatric diagnosis, antipsychotic medication use, and cigarette smoking (P>0.006 for all outcomes). Conclusions: Our findings indicate that in this sample of patients with psychiatric diagnoses, patients who use cannabis had a similar cardiometabolic profile to non-users. Patterns of cannabis use highlight the importance of reducing cannabis consumption and preventing or slowing the progression of CUD in this population, as well as limiting adolescent exposure to cannabis. / Thesis / Master of Science (MSc) / The endocannabinoid system regulates several processes in the body via endocannabinoid signaling, and cannabinoids found in cannabis can change endocannabinoid system function. Cardiovascular events and changes in appetite have been noted with cannabis use, and this is especially important in some vulnerable populations at risk of increased cannabis use; one of these groups include patients with psychiatric conditions who tend to use cannabis but also already have an increased cardiometabolic risk. In this thesis, the relationship between cannabis use and cardiometabolic risk was examined in 200 patients, and patterns and determinants of cannabis use explored. Our results demonstrated that of the 79 cannabis users, most consumed cannabis daily, and had a moderate cannabis use disorder. On average, users began cannabis consumption at 15 years of age and for an average duration of 14 years. Moderate cannabis use was not related to cardiometabolic risk in these patients. Our data demonstrate the need to prevent or slow the progression of cannabis use disorder in these patients and the importance of reducing early exposure of adolescents to cannabis.

No description available.

For the first time in many decades, a hemp pilot program was initiated in Virginia in 2016. Outdoor surveys were conducted in the 2017 and 2018 field seasons to record insect presence and feeding injury to plants. Multiple insect pests were present, including corn earworm (Helicoverpa zea [Boddie]) (Lepidoptera: Noctuidae), brown marmorated stink bug (Halyomorpha halys [Stål]) (Hemiptera: Pentatomidae), and cannabis aphid (Phorodon cannabis) (Hemiptera: Aphididae). In 2019, indoor production surveys revealed that cannabis aphid, twospotted spider mite (Tetranychus urticae Koch) (Acari: Tetranychidae), and hemp russet mite (Aculops cannabicola [Farkas]) (Acari: Eriophyidae) would likely cause production issues. Very little is known about the impact of insect defoliation in hemp so studies were conducted in 2018-2020 to determine impacts on yield and cannabinoid content of grain and cannabinoid variety hemp due to leaf surface area loss. In Virginia over two growing seasons, manual removal of leaf tissue in grain and CBD cultivars did not significantly impact observable effects on physical yield (seed or bud weight) or cannabinoid content (CBD or THC) at time of harvest. Corn earworm is the major pest of hemp produced outdoors and studies occurred to evaluate monitoring and management strategies. Pheromone traps may be valuable in determining when corn earworm moths are present in the vicinity of hemp fields but are not useful in predicting larval presence in buds or final crop damage. Larval presence and final crop damage are related. Brown marmorated stink bug does not appear to be a concern in hemp, at least at this time. / Doctor of Philosophy / For the first time in many decades, a hemp pilot program was initiated in Virginia in 2016. Outdoor surveys were conducted in the 2017 and 2018 field seasons to record insect presence and feeding injury to plants. Multiple insect pests were present, including corn earworm, brown marmorated stink bug, and cannabis aphid. In 2019, indoor production surveys revealed that cannabis aphid, twospotted spider mite, and hemp russet mite would likely cause production issues. Very little is known about the impact of leaf area loss due to insect feeding in hemp so studies were conducted in 2018-2020 to determine impacts on yield and cannabinoid content of grain and cannabinoid variety hemp due to leaf surface area loss. In Virginia over two growing seasons, manual removal of leaf tissue in grain and CBD cultivars did not significantly impact observable effects on physical yield (seed or bud weight) or cannabinoid content (CBD or THC) at time of harvest. Corn earworm is the major pest of hemp produced outdoors and studies occurred to evaluate monitoring and management strategies. Pheromone traps may be valuable in determining when corn earworm moths are present in the vicinity of hemp fields but are not useful in predicting larval presence in buds or final crop damage. Larval presence and final crop damage are related. Brown marmorated stink bug does not appear to be a concern in hemp, at least at this time.