Cannabis Dependence (cannabis + dependence)

Distribution by Scientific Domains


Selected Abstracts


Prediction of twelve-month service disengagement from an early intervention in psychosis service

EARLY INTERVENTION IN PSYCHIATRY, Issue 3 2007
Mark Turner
Abstract Aim: The aim is to examine disengagement in an early psychosis treatment service and contrast clinical and demographic variables of patients who disengage against those who do not. Methods: Those with termination of treatment, despite therapeutic need within 12 months of entry (disengagers) (n = 57; 24.6%), were compared with those who remained in treatment at 12 months (n = 175) on a range of clinical and demographic variables collected at admission. After testing the difference between proportions, data analysis was conducted using methods of logistic regression. Results: Alcohol and/or cannabis abuse/dependence, initial diagnosisother than mood disorder, long duration of untreated psychosis, lower Positive and Negative Syndrome Scale total symptoms, and lower insight at referral accounted for 27% of variance in patient ,disengagement' within 12 months. Conclusion: A significant proportion of patients with first episode psychosis disengage from treatment within 12 months. Despite a number of factors being associated with disengagement, prediction using admission factors was poor. Early Intervention in Psychosis Services would benefit from increased attention to alcohol and drug problems, trying to reduce the duration of untreated psychosis, improving psychiatric symptoms and increasing insight in all patients to decrease service disengagement. [source]


GENETIC STUDY: 5-HTTLPR polymorphism, mood disorders and MDMA use in a 3-year follow-up study

ADDICTION BIOLOGY, Issue 1 2010
Rocío Martín-Santos
ABSTRACT A 3-year longitudinal prospective study was conducted to compare the incidence of substance use disorders (SUD) and non-substance use disorders (NSUD) among ecstasy users and two control groups: one of cannabis users and the other of non-drug users. The 5-HTTLPR polymorphism related to NSUD was also studied. A total of 94 subjects were included: 37 ecstasy users, 23 cannabis users and 34 non-drug users. SUD and NSUD disorders were diagnosed according to the fourth edition of the Diagnostic and Statistical Manual of Mental Health Disorders criteria using the Psychiatric Research Interview for Substance and Mental Disorders. Incidence Rates (IR) are presented. The 5-HTTLPR polymorphism was analyzed. Hardy,Weinberg equilibrium was studied. The results of the study showed that the highest IR of SUD was cannabis abuse/dependence in both the ecstasy (IR: 48.6/100 person,year) and cannabis (IR: 2.5/100 person,year) groups. There were no new cases of SUD in non-drug users at follow-up. The highest IR of NSUD was primary mood disorder in both the ecstasy (IR: 4.2/100 person,year) and in the non-drug (IR: 1.3/100 person,year) groups (P < 0.282). There were no new cases of NSUD in the cannabis group at follow-up. 5-HTTLPR polymorphism was associated with lifetime of primary mood disorders in ecstasy group (P = 0.018). Ecstasy use was associated with a higher rate of cannabis abuse/dependence disorders and mood disorders than cannabis use. In the ecstasy users, 5-HTTLPR polymorphism may result in a high vulnerability to primary mood disorders. [source]


Gender differences in bipolar disorder: age of onset, course, comorbidity, and symptom presentation

BIPOLAR DISORDERS, Issue 2 2005
Izabela Kawa
Objective:, To determine whether men and women with bipolar disorder differ in age of onset, course of illness, number of suicide attempts, comorbidity rates and symptom presentation. Method:, Data were collected from 211 (121 women; 90 men) adults using the Diagnostic Interview for Genetic Studies, medical records, and additional information gathered from relatives. Results:, Most gender comparisons showed no evidence of differences. Nonetheless, more men than women reported mania at the onset of bipolar I disorder. Men also had higher rates of comorbid alcohol abuse/dependence, cannabis abuse/dependence, pathological gambling and conduct disorder. Men were more likely to report ,behavioural problems' and ,being unable to hold a conversation' during mania. Women reported higher rates of comorbid eating disorders, and weight change, appetite change and middle insomnia during depression. Conclusions:, Men and women were generally similar in their symptom presentation, age of onset of bipolar disorder, and in the total number of mood episodes. However, they differed in the type of episode at onset and comorbidity patterns. [source]


First positive reactions to cannabis constitute a priority risk factor for cannabis dependence

ADDICTION, Issue 10 2009
Yann Le Strat
ABSTRACT Aim To assess the association between first reactions to cannabis and the risk of cannabis dependence. Design A cross-sectional population-based assessment in 2007. Setting A campus in a French region (Champagne-Ardennes). Participants A total of 1472 participants aged 18,21 years who reported at least one life-time cannabis consumption, of 3056 students who were screened initially [the Susceptibility Addiction Gene Environment (SAGE) study]. Measurements Positive and negative effects of first cannabis consumptions, present cannabis dependence and related risk factors were assessed through questionnaires. Findings The effects of first cannabis consumptions were associated dose-dependently with cannabis dependence at age 18,21 years, both according to the transversal approach of the SAGE study and to the prospective cohort of the Christchurch Health and Development Study (CHDS) assessed at the age of 25 years. Participants of the SAGE study who reported five positive effects of their first cannabis consumption had odds of life-time cannabis dependence that were 28.7 (95% confidence interval: 14.6,56.5) higher than those who reported no positive effects. This association remains significant after controlling for potentially confounding factors, including individual and familial variables. Conclusions This study suggests an association between positive reactions to first cannabis uses and risk of life-time cannabis dependence, this variable having a central role among, and through, other risk factors. [source]


Are adolescents who moderate their cannabis use at lower risk of later regular and dependent cannabis use?

ADDICTION, Issue 5 2009
Wendy Swift
ABSTRACT Aims To examine whether moderation of cannabis use among adolescent cannabis users is associated with reductions in cannabis use frequency and risk of dependence in young adulthood. Design Ten-year representative cohort study with six surveys in adolescence (mean age 14.9,17.4 years) and two in young adulthood (mean age 20.7 and 24.1 years). Participants Inception cohort of 1943 Victorian secondary school students (96% response rate), with 1520 (78% of adolescent participants) interviewed in the final wave. Measurements Participants were classified into six groups according to the maximum level of adolescent use and the extent of subsequent moderation in such use: non-users, occasional to abstinence, occasional persisting, weekly to abstinence, weekly to occasional and weekly persisting. Outcome measures were weekly+ cannabis use and DSM-IV cannabis dependence at 20 and 24 years. Findings Thirty-one per cent reported cannabis use during adolescence. Most adolescent users had moderated their use: from occasional to abstinence (71% of occasional users), weekly to abstinence or weekly to occasional (28% and 48% of weekly+ users, respectively). By age 24, both occasional use groups were at similar, elevated risk of regular and dependent cannabis use compared to non-users. Weekly+ adolescent users were at greatest risk of these outcomes, although the weekly to abstinence group exhibited lower risk than those in the weekly persisting and weekly to occasional groups, who were at similar risk. Conclusions While many young people have dynamic cannabis use patterns, a pattern of moderating adolescent cannabis use was associated with less risk of later problematic use than among those persisting, but risks were still elevated substantially compared with never-users. [source]


A longitudinal study of cannabis use and mental health from adolescence to early adulthood

ADDICTION, Issue 4 2000
Rob McGee
Aims. To examine the longitudinal association between cannabis use and mental health. Design. Information concerning cannabis use and mental health from 15 to 21 years was available for a large sample of individuals as part of a longitudinal study from childhood to adulthood. Participants. Participants were enrolled in the Dunedin Multidisciplinary Health and Development Study, a research programme on the health, development and behaviour of a large group of New Zealanders born between 1 April 1972 and 31 March 1973. Measurements. Cannabis use and identification of mental disorder was based upon self-report as part of a general assessment of mental health using a standard diagnostic interview. Daily smoking and alcohol use at age 15 were assessed by self-report. Indices of family socio-economic status, family climate and parent - child interaction were formed using information gathered from parent report and behavioural observations over early childhood. Childhood behaviour problems were assessed by parent and teacher report. Attachment to parents was assessed in adolescence. Findings. Cross-sectional associations between cannabis use and mental disorder were significant at all three ages. Both outcome variables shared similar pathways of low socio-economic status and history of behaviour problems in childhood, and low parental attachment in adolescence. Mental disorder at age 15 led to a small but significantly elevated risk of cannabis use at age 18; by contrast, cannabis use at age 18 elevated the risk of mental disorder at age 21. The latter association reflected the extent to which cannabis dependence and other externalizing disorders at age 21 were predicted by earlier level of involvement with cannabis. Conclusions. The findings suggest that the primary causal direction leads from mental disorder to cannabis use among adolescents and the reverse in early adulthood. Both alcohol use and cigarette smoking had independent associations with later mental health disorder. [source]


PRECLINICAL STUDY: FULL ARTICLE: Altered architecture and functional consequences of the mesolimbic dopamine system in cannabis dependence

ADDICTION BIOLOGY, Issue 3 2010
Saturnino Spiga
ABSTRACT Cannabinoid withdrawal produces a hypofunction of mesencephalic dopamine neurons that impinge upon medium spiny neurons (MSN) of the forebrain. After chronic treatment with two structurally different cannabinoid agonists, ,9 -tetrahydrocannabinol and CP55 940 (CP) rats were withdrawn spontaneously and pharmacologically with the CB1 antagonist SR141716A (SR). In these two conditions, evaluation of tyrosine hydroxylase (TH)-positive neurons revealed significant morphometrical reductions in the ventrotegmental area but not substantia nigra pars compacta of withdrawn rats. Similarly, confocal analysis of Golgi,Cox-stained sections of the nucleus accumbens revealed a decrease in the shell, but not the core, of the spines' density of withdrawn rats. Administration of the CB1 antagonist SR to control rats, provoked structural abnormalities reminiscent of those observed in withdrawal conditions and support the regulatory role of cannabinoids in neurogenesis, axonal growth and synaptogenesis by acting as eu-proliferative signals through the CB1 receptors. Further, these measures were incorporated into a realistic computational model that predicts a strong reduction in the excitability of morphologically altered MSN, yielding a significant reduction in action potential output. These pieces of evidence support the tenet that withdrawal from addictive compounds alters functioning of the mesolimbic system and provide direct morphological evidence for functional abnormalities associated with cannabinoid dependence at the level of dopaminergic neurons and their postsynaptic counterpart and are coherent with recent hypothesis underscoring a hypodopaminergic state as a distinctive feature of the ,addicted brain'. [source]


GENETIC STUDY: Heritability and a genome-wide linkage analysis of a Type II/B cluster construct for cannabis dependence in an American Indian community

ADDICTION BIOLOGY, Issue 3 2009
Cindy L. Ehlers
ABSTRACT Subtyping of substance dependence disorders holds promise for a number of important research areas including phenotyping for genetic studies, characterizing clinical course, and matching treatment and prevention strategies. This study sought to investigate whether a dichotomous construct similar to Babor's Types A/B and Cloninger's Types I/II for alcohol dependence can be identified for cannabis dependence in a Native American sample. In addition, heritability of this construct and its behavior in a genetic linkage analyses were evaluated. Information on cannabis use and dependence symptoms and other psychiatric disorders was obtained using the Semi-Structured Assessment for the Genetics of Alcoholism from a community sample of 606 American Indians. Hierarchical average linkage and K means cluster analysis was used, and a three-cluster solution was found to generate the best separation of variables. Ninety-one per cent of cannabis-dependent participants fell into one of the two subtypes: Type A/I cluster (n = 114, 56%) and Type B/II cluster (n = 70, 35%). Heritability (estimated using Sequential Oligogenic Linkage Analysis Routines) was only significant for the Type B/II cluster (h2 = 0.44, SE = 0.18, P < 0.01). Evidence for linkage was found for the Type B/II cluster (versus no diagnosis) on chromosome 16 [at 139 centimorgans (cM), Log of the Odds (LOD) score = 4.4], and on chromosome 19 (at 74 cM, LOD score = 6.4). Regions of interest for this phenotype (LOD > 1.5) were also located on chromosomes 14, 21, 22. These findings suggest that a Type B/II cannabis dependence phenotype can be identified in this population and that it is in part heritable and linked to areas of the genome identified previously for drug dependence phenotypes in this population as well as in other studies. [source]


Treatment of Cannabis Use Disorders: A Review of the Literature

THE AMERICAN JOURNAL ON ADDICTIONS, Issue 5 2007
Benjamin R. Nordstrom MD
Cannabis is the most widely used illicit drug in the United States. Despite the fact that there are large numbers of people with cannabis dependence, relatively little attention has been paid to the treatment of this condition. This article seeks to critically review the existing literature about the various psychosocial and pharmacologic treatments of cannabis dependence. We begin with a discussion of the early treatment literature which draws primarily from anecdotal experience and open, uncontrolled trials and proceed through two recent, large, randomized controlled trials of psychotherapies for the treatment of cannabis dependence. We conclude that while a number of psychotherapies have been found to be effective in treating this disorder, with the exception of adding vouchers to reinforce negative urine toxicology screens, no form of psychotherapy has been found to be more effective than any other. In addition, we review the only two clinical pharmacotherapy trials for cannabis dependence as well as the pre-clinical laboratory pharmacotherapy trials in cannabis dependent individuals. We also review pertinent dual-diagnosis pharmacotherapy trials and discuss potential future directions in treatment research for the pharmacotherapy of cannabis dependence. [source]


Approach to treatment of mental illness and substance dependence in remote Indigenous communities: Results of a mixed methods study

AUSTRALIAN JOURNAL OF RURAL HEALTH, Issue 4 2009
Tricia Nagel
Abstract Objective:,To develop and evaluate a culturally adapted brief intervention for Indigenous people with chronic mental illness. Design:,A mixed methods design in which an exploratory phase of qualitative research was followed by a nested randomised controlled trial. Setting:,Psycho-education resources and a brief intervention, motivational care planning (MCP), were developed and tested in collaboration with aboriginal mental health workers in three remote communities in northern Australia. Participants:,A total of 49 patients with mental illness and 37 carers were recruited to a randomised controlled trial that compared MCP (n = 24) with a clinical control condition (treatment as usual, n = 25). Intervention:,The early treatment group received MCP at baseline and the late treatment group received delayed treatment at six months. Main outcome measures:,The primary outcome was mental health problem severity as measured by the health of the nation outcome scales. Secondary measures of well-being (Kessler 10), life skills, self-management and substance dependence were chosen. Outcome assessments were performed at baseline, six-month, 12-month and 18-month follow up. Results:,Random effects regression analyses showed significant advantage for the treatment condition in terms of well-being with changes in health of the nation outcome scales (P < 0.001) and Kessler 10 (P = 0.001), which were sustained over time. There was also significant advantage for treatment for alcohol dependence (P = 0.05), with response also evident in cannabis dependence (P = 0.064) and with changes in substance dependence sustained over time. Conclusions:,These results suggest that MCP is an effective treatment for Indigenous people with mental illness and provide insight into the experience of mental illness in remote communities. [source]