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Michael Lynskey

Publications and source records attributed to Michael Lynskey.

26 records · Page 2Linked to original sources
PubMed2002

The structure of cannabis dependence in the community.

BACKGROUND: Cannabis is the most widely used illicit drug in developed countries, and has a significant impact on mental and physical health in the general population. However, the validity of common diagnostic schemes and their applicability to cannabis abuse and dependence is poorly understood. This paper describes a confirmatory factor analysis of the DSM-IV cannabis abuse and dependence criteria, using general population data. METHODS: Data from cannabis users (n=722) were obtained from a cross-sectional study of a large and representative sample of the Australian general population. The DSM-IV criteria for cannabis abuse and dependence were assessed using the CIDI-AUTO. RESULTS: Approximately, one in 12 Australians (7.1%) had used cannabis more than five times in the past 12 months and 56.5% of these reported at least one DSM-IV cannabis abuse or dependence criteria. Within the adult population, 2.2% met criteria for a cannabis use disorder (0.7% abuse and 1.5% dependence). Confirmatory factor analysis indicated that both a one- and two-factor model for cannabis use disorder provided an adequate fit to the data. However, the estimated correlation between the abuse and dependence factors in the two-factor model was extremely high (0.99). CONCLUSIONS: A one-factor model provided the most parsimonious model of the cannabis abuse and dependence criteria.

Australia↗
PubMed2002

Cannabis use and mental health in young people: cohort study.

OBJECTIVE: To determine whether cannabis use in adolescence predisposes to higher rates of depression and anxiety in young adulthood. DESIGN: Seven wave cohort study over six years. SETTING: 44 schools in the Australian state of Victoria. PARTICIPANTS: A statewide secondary school sample of 1601 students aged 14-15 followed for seven years. MAIN OUTCOME MEASURE: Interview measure of depression and anxiety (revised clinical interview schedule) at wave 7. RESULTS: Some 60% of participants had used cannabis by the age of 20; 7% were daily users at that point. Daily use in young women was associated with an over fivefold increase in the odds of reporting a state of depression and anxiety after adjustment for intercurrent use of other substances (odds ratio 5.6, 95% confidence interval 2.6 to 12). Weekly or more frequent cannabis use in teenagers predicted an approximately twofold increase in risk for later depression and anxiety (1.9, 1.1 to 3.3) after adjustment for potential baseline confounders. In contrast, depression and anxiety in teenagers predicted neither later weekly nor daily cannabis use. CONCLUSIONS: Frequent cannabis use in teenage girls predicts later depression and anxiety, with daily users carrying the highest risk. Given recent increasing levels of cannabis use, measures to reduce frequent and heavy recreational use seem warranted.

Adolescent↗
PubMed2002

'Diagnostic orphans' among young adult cannabis users: persons who report dependence symptoms but do not meet diagnostic criteria.

OBJECTIVE: To examine the characteristics of 'diagnostic orphans' among cannabis users-those who report one or two symptoms of DSM-IV dependence but do not meet diagnostic criteria for DSM-IV abuse or dependence. METHOD: Data were collected from a representative population cohort of 1601 young adults aged 20-21 years. Those who reported that they had used cannabis at least weekly at some point within the past year were assessed for symptoms of DSM-IV cannabis abuse and dependence using the Composite International Diagnostic Interview. RESULTS: Approximately 2.8% of the cohort could be classified as diagnostic orphans, with another 3.0 and 7.5% meeting criteria for abuse and dependence, respectively. Diagnostic orphans were: similar to those who met criteria for cannabis abuse or dependence in terms of demographic characteristics; similar to those who met criteria for cannabis abuse in terms of cannabis use patterns; and similar to those who met criteria for abuse and dependence in their rates of heavy alcohol use and DSM-IV alcohol dependence. However, they did not appear to have elevated rates of illicit drug use or mental health problems compared to non users. CONCLUSIONS: Diagnostic orphans reported using cannabis in a manner similar to persons meeting criteria for cannabis abuse, and had similar rates of alcohol dependence and other illicit drug use. Strict adherence to DSM-IV diagnoses of abuse and dependence may overlook a substantial proportion of young persons who experience cannabis-related problems. There is a need to consider (a) subthreshold levels of cannabis-related problems among those seeking treatment for other problems; and (b) interventions for this group to prevent escalation of such problems.

Adult↗
PubMed2002

Cannabis dependence in young adults: an Australian population study.

OBJECTIVES: The symptomatology of cannabis dependence remains ill-defined and its importance controversial. Compared with alcohol dependence, the symptom profile of cannabis dependence has received little attention. We aimed to (a) report cannabis use in a representative population of young adults, (b) examine cannabis dependence symptoms according to frequency in the dependence syndrome and (c) contrast the symptomatology of cannabis and alcohol syndromes. METHODS: 1601 young adults (mean age 20.7 years) from an Australian longitudinal cohort study (N=2032) were surveyed in 1998. Regular substance users were assessed for DSM-IV cannabis and alcohol dependence. Prevalence estimates allowed for sampling variation and attrition. RESULTS: Fifty-nine per cent reported life-time use of cannabis, 17% used at least weekly and 7% (11% males, 4% females) met criteria for cannabis dependence. Symptom prevalence in dependent cannabis users was: persistent desire 91%; unintentional use 84%; withdrawal 74%; excessive time obtaining/using 74%; continued use despite health problems 63%; tolerance 21%; and social consequences 18%. The combination of withdrawal, persistent desire and unintentional use was reported by 57%. Dependent cannabis users reported compulsive and out-of-control use more frequently than dependent alcohol users, withdrawal similarly and tolerance considerably less often. CONCLUSIONS: Cannabis use appears to be normative behaviour in young Australians. Progression beyond weekly use of cannabis carries a significant risk of dependence that should be considered in the public health response. The differing profiles of cannabis and alcohol dependence, particularly with regard to craving, draws attention to the need for further study of cannabis dependence as an important and distinct disorder in young adults.

Adolescent↗
PubMed2002

Substance use disorders in an Australian community survey.

A community survey of the common mental disorders in a geographically defined treatment service area was used to explore the socio-demographic correlates and service utilization of people with alcohol and drug use disorders living in the area. These data represent the most comprehensive data on substance use disorders in a defined geographic region in Australia. Alcohol and drug use disorders were most likely to be found in the young, with those aged 18-34 years being three times more likely to have an alcohol use disorder than those aged 55 years and over. A third (33%) of those people with an alcohol use disorder and 42% of those with a drug use disorder had consulted a health professional in the past 12 months for their substance use disorder.

Adolescent↗
PubMed2002

Mental health of teenagers who use cannabis. Results of an Australian survey.

BACKGROUND: There is concern in the community about increasing cannabis use and its potential effect on health. AIMS: To ascertain the prevalence of cannabis use among Australian adolescents, associations with mental health problems, risk behaviours and service use. METHOD: Examination of data from a national representative sample of households comprising 1261 adolescents aged 13-17 years. Parents completed a psychiatric interview and questionnaires while adolescents completed questionnaires. RESULTS: One-quarter of the adolescents in the sample had used cannabis. There were no gender differences. Use increased rapidly with age, was more common in adolescents living with a sole parent and was associated with increased depression, conduct problems and health risk behaviours (smoking, drinking) but not with higher use of services. CONCLUSIONS: Cannabis use is very prevalent. The association with depression, conduct problems, excessive drinking and use of other drugs shows a malignant pattern of comorbidity that may lead to negative outcomes.

Adolescent↗