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Wayne Hall

Publications and source records attributed to Wayne Hall.

At least 55 records · Page 3Linked to original sources
PubMed2003

Decreased heroin availability in Sydney in early 2001.

AIM: To examine the veracity of reports of a substantial decrease in the availability of heroin in Sydney in January 2001. DESIGN: Cross-sectional survey. SETTING: Sydney, Australia. PARTICIPANTS: Forty-one injecting drug users (IDUs) and 10 key informants (KIs). FINDINGS: Almost all IDUs (93%) reported that heroin was harder to obtain at the time of interview (mid-February 2001) than it was before Christmas 2000 and KIs concurred. IDUs (83%) and KIs (70%) also reported that the price of heroin had increased since Christmas, and that the purity of heroin had decreased (IDUs 73%; KIs 80%). Almost all IDUs reported a reduction in their heroin use and a subsequent increase in other drug use, particularly cocaine, benzodiazepines and cannabis. Similar reports about IDUs came from nine of the 10 KIs. Over half the KIs reported an increase in both property and violent crime as a result of the heroin shortage. This crime was reportedly occurring mainly between heroin suppliers and/or IDUs. Reports from other Australian jurisdictions suggest that the shortage was not specific to Sydney. CONCLUSIONS: The reduction in the availability of heroin provides a unique opportunity to investigate the impact of supply reduction.

Adolescent↗
PubMed2003

Exploring the association between cannabis use and depression.

AIM: To examine the evidence on the association between cannabis and depression and evaluate competing explanations of the association. METHODS: A search of Medline, Psychinfo and EMBASE databases was conducted. All references in which the terms 'cannabis', 'marijuana' or 'cannabinoid', and in which the words 'depression/depressive disorder/depressed', 'mood', 'mood disorder' or 'dysthymia' were collected. Only research studies were reviewed. Case reports are not discussed. RESULTS: There was a modest association between heavy or problematic cannabis use and depression in cohort studies and well-designed cross-sectional studies in the general population. Little evidence was found for an association between depression and infrequent cannabis use. A number of studies found a modest association between early-onset, regular cannabis use and later depression, which persisted after controlling for potential confounding variables. There was little evidence of an increased risk of later cannabis use among people with depression and hence little support for the self-medication hypothesis. There have been a limited number of studies that have controlled for potential confounding variables in the association between heavy cannabis use and depression. These have found that the risk is much reduced by statistical control but a modest relationship remains. CONCLUSIONS: Heavy cannabis use and depression are associated and evidence from longitudinal studies suggests that heavy cannabis use may increase depressive symptoms among some users. It is still too early, however, to rule out the hypothesis that the association is due to common social, family and contextual factors that increase risks of both heavy cannabis use and depression. Longitudinal studies and studies of twins discordant for heavy cannabis use and depression are needed to rule out common causes. If the relationship is causal, then on current patterns of cannabis use in the most developed societies cannabis use makes, at most, a modest contribution to the population prevalence of depression.

Adolescent↗
PubMed2003

Alcohol and other drug use disorders among older-aged people.

In Australia people aged 65 years or older currently comprise 12.1% of the population. This has been estimated to rise to 24.2% by 2051. Until recently there has been relatively little research on alcohol and other drug use disorders among these individuals but, given the ageing population, this issue is likely to become of increasing importance and prominence. Epidemiological research shows a strong age-related decline in the prevalence of alcohol and other drug use disorders with age. Possible reasons for this include: age-related declines in the use and misuse of alcohol and other drugs; increased mortality among those with a lifetime history of alcohol and other drug use disorders; historical differences in exposure to and use of alcohol and other drugs. Despite the age-related decline in the prevalence of these disorders, they do still occur among those aged 65 years or older and, given historical changes in exposure to and use of illicit drugs, it likely that the prevalence of these disorders among older-aged individuals will rise. Specific issues faced by older-aged individuals with alcohol and other drug use problems are discussed. These include: interactions with prescribed medications, under-recognition and treatment of alcohol and drug problems, unintentional injury and social isolation. Finally, a brief discussion of treatment issues is provided.

Aged↗
PubMed2003

Patterns of co-morbidity between alcohol use and other substance use in the Australian population.

The present study describes patterns of co-morbidity between alcohol use and other substance use problems in the Australian population using data from the 1997 National Survey of Mental Health and Well-Being. Multiple regression analyses examined whether the observed associations between alcohol and other drug use disorders were explained by other variables, including demographic characteristics and neuroticism. We also assessed whether the presence of co-morbid substance use disorders affected treatment seeking for a mental health problem. Alcohol use was related strongly to the use of other substances. Those who did not report alcohol use within the past 12 months were less likely to report using tobacco, cannabis, sedatives, stimulants or opiates. Higher rates again were observed among those with alcohol use disorders: half (51%) of those who were alcohol-dependent were regular tobacco smokers, one-third had used cannabis (32%); 15% reported other drug use; 15% met criteria for a cannabis use disorder and 7% met criteria for another drug use disorder. These associations were not accounted for by the demographic and other variables considered here. Co-morbid substance use disorders (sedatives, stimulants or opioids) predicted a high likelihood of seeking treatment for a mental health problem among alcohol-dependent people.

Adolescent↗
PubMed2003

Heroin overdose: research and evidence-based intervention.

Drug overdose is a major cause of premature death and morbidity among heroin users. This article examines recent research into heroin overdose to inform interventions that will reduce the rate of overdose death. The demographic characteristics of overdose cases are discussed, including factors associated with overdose: polydrug use, drug purity, drug tolerance, routes of administration, and suicide. Responses by heroin users at overdoses are also examined. Potential interventions to reduce the rate of overdose and overdose-related morbidity are examined in light of the emerging data in this field.

Australia↗
PubMed2003

Medical marijuana initiatives : are they justified? How successful are they likely to be?

The principal constituent of cannabis, Delta(9)-tetrahydrocannabinol (THC), is moderately effective in treating nausea and vomiting, appetite loss, and acute and chronic pain. Oral THC (dronabinol) and the synthetic cannabinoid, nabilone, have been registered for medical use in the US and UK, but they have not been widely used because patients find it difficult to titrate doses of these drugs. Advocates for the medical use of cannabis argue that patients should be allowed to smoke cannabis to relieve these above-mentioned symptoms. Some US state governments have legislated to allow the medical prescription of cannabis, but the US federal government has tried to prevent patients from obtaining cannabis and threatened physicians who prescribe it with criminal prosecution or loss of their licence to practise. In the UK and Australia, committees of inquiry have recommended medical prescription (UK) and exemption from criminal prosecution (New South Wales, Australia), but governments have not accepted these recommendations. The Canadian government allows an exemption from criminal prosecution to patients with specified medical conditions. It has recently legislated to provide cannabis on medical prescription to registered patients, but this scheme so far has not been implemented. Some advocates argue that legalising cannabis is the only way to ensure that patients can use it for medical purposes. However, this would be contrary to international drug control treaties and is electorally unpopular. The best prospects for the medical use of cannabinoids lie in finding ways to deliver THC that do not involve smoking and in developing synthetic cannabinoids that produce therapeutic effects with a minimum of psychoactive effects. While awaiting these developments, patients with specified medical conditions could be given exemptions from criminal prosecution to grow cannabis for their own use, at their own risk.

Antiemetics↗
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

Cannabis and psychosis.

There has been considerable debate about the reasons for the association observed between cannabis use and psychosis in both clinical and general population samples. Among the hypotheses proposed to explain the association are the following: 1) common factors explain the co-occurrence; 2 cannabis causes psychosis that would not have occurred in the absence of cannabis use; 3) cannabis precipitates psychosis among persons who were vulnerable to developing the disorders; 4) cannabis use worsens or prolongs psychosis among those who have already developed the disorder; and 5) that persons with psychosis are more likely to become regular or problematic cannabis users than persons without psychosis. This article evaluates the evidence on each of these hypotheses, including recent research on the role of the cannabinoid receptor system in schizophrenia. The evidence suggests that common factors do not explain the comorbidity between cannabis use and psychosis, and it is unlikely that cannabis use causes psychosis among persons who would otherwise not have developed the disorder. The evidence is more consistent with the hypotheses that cannabis use may precipitate psychosis among vulnerable individuals, increase the risk of relapse among those who have already developed the disorder, and may be more likely to lead to dependence in persons with schizophrenia.

Adult↗
PubMed2002

Heroin use in New South Wales, Australia, 1996-2000: 5 year monitoring of trends in price, purity, availability and use from the Illicit Drug Reporting System (IDRS).

AIMS: To document trends in the price, purity, availability and use of heroin in New South Wales detected by the Illicit Drug Reporting System (IDRS) between 1996 and 2000, and to demonstrate the utility of the IDRS in identifying such trends. DESIGN: The IDRS compares information derived from interviews with injecting drug users, key informants who work in the illicit drugs field, and key indicator data on illicit drug trends. SETTING: New South Wales, Australia. FINDINGS: The price of heroin approximately halved over this period, from a median of A$400 per gram in 1996 to A$220 per gram in 2000. While the price of heroin fell dramatically over the study period, the purity of police seizures of the drug was high across all years, ranging between 62% and 71%. In all years heroin was considered easy to obtain by both heroin users who purchased the drug, and by key informants from the law enforcement and health fields. Concurrent with the large fall in heroin prices, there appeared to have been an increase in the number of heroin users. Between 1997 and 1998 there was a sharp increase in the injecting use of cocaine by heroin users in NSW, a pattern that has persisted. CONCLUSIONS: Regular and formal monitoring of illicit drug trends provides timely data in a systematic way to inform health and law enforcement policies towards current and emerging illicit drug problems.

Adolescent↗