Methamphetamine use and emergency services in Australia: a scoping review

Step 1: Identifying the research question

Coverage of methamphetamine use in the mass media has been increasing, as has utilisation of emergency medical services for methamphetamine-related events (Hughes et al, 2011; Lim et al, 2014; Lloyd et al, 2014). The research team identified two broad research questions designed to identify relevant information about methamphetamine prevalence and its impact on emergency ambulance services: (a) Who is currently using methamphetamine in Australia and how has prevalence changed over time? (b) What is the impact of methamphetamine use on emergency ambulance services in Australia?

Step 2: Identifying the relevant studies

The search strategy used two separate engines OVID and Scopus. The OVID engine was used to search Medline, Embase, EBM Reviews and PsycARTICLES full text, while Scopus was searched separately. The MeSH terms used in the database search included psychostimulant*, amphetamine*, methamphetamine* and Australia. Grey literature such as government reports were located through online searches as well as examination of reference lists from relevant peer-reviewed publications.

Step 3: Study selection

Titles and abstracts of articles retrieved in Step 2 were screened independently by two authors using the inclusion and exclusion criteria outlined in Table 1. Articles selected by both researchers were collated and duplicates were removed. The full text of selected studies was then read in depth to ensure relevance to this study, and a final number of included articles was agreed upon by both researchers.

Step 4: Charting the data

Data from the included articles was placed into tables related to their study design (Tables 2–4). These tables include information about the article such as journal title, article title, aims, results and conclusions. The data was extracted by one researcher and reviewed by the other to ensure relevance to the research questions.

Step 5: Collating, summarising and reporting results

Relevant themes to address the research questions were established by the research team. The themes are explored in depth in the discussion portion of this paper.

Step 6: Consultation

The scoping methodology used in this study includes an optional sixth stage of consulting relevant parties external to the authors, such as experts in the area of interest or pertinent community organisations. Given the lack of previous research regarding the impact of methamphetamine on emergency ambulance services, this stage was omitted.

Demographics of methamphetamine users

Seven articles described the demographics of methamphetamine users as a whole (McKetin et al, 2006a; 2006b; Degenhardt et al, 2008; Quinn et al; 2013; Al-Obaidi and Fletcher, 2014; Lappin et al, 2016; Paratz et al, 2016). These articles reported that the average age of methamphetamine users was range of ages from 26.5–34 years, although one paper simply reported the median age to be <40 years (Lappin et al, 2016). The majority of users were male; however, the proportion varied considerably between studies from 57–76% (McKetin et al, 2006a; 2006b; Degenhardt et al, 2008; Quinn et al, 2013; Al-Obaidi and Fletcher, 2014; Lappin et al, 2016; Paratz et al, 2016). Unemployment was high, and equally variable between 52–85.6% (McKetin et al, 2006a; 2006b; Degenhardt et al, 2008; Quinn et al, 2013; Al-Obaidi and Fletcher, 2014; Lappin et al, 2016). The majority of users were Australian born (80–87%), and almost all users spoke English as their language of choice (McKetin et al, 2006a; 2006b; Degenhardt et al, 2008; Quinn et al, 2013; Al-Obaidi and Fletcher; 2014). Few users had finished high school education, with the average years of completed schooling in all studies being 10 years (McKetin et al, 2006a; 2006b; Degenhardt et al, 2008; Quinn et al, 2013; Al-Obaidi and Fletcher; 2014) Some form of tertiary education was completed by 46% of users while 6–11% had completed a university degree (McKetin et al, 2006a; 2006b; Degenhardt et al, 2008; Quinn et al, 2013; Al-Obaidi and Fletcher, 2014). Rates of dependence also varied between 45.6–60% (McKetin et al, 2006a; 2006b; Degenhardt et al, 2008; Quinn et al, 2013; Al-Obaidi and Fletcher, 2014; Lappin et al, 2016).

A number of articles sampled specific populations and their methamphetamine use. These specific populations show unique differences in particular areas of Australia. Wallace et al's study showed rural and regional users have a higher median age and a higher rate of homelessness than the other studies (Wallace et al, 2009). Roche et al's study of employed methamphetamine users showed that employed users were more likely to be younger, between 18-29 years of age (Roche et al, 2008). Another paper showed users of ecstasy who also used methamphetamine were more likely to be employed and be younger than those who primarily used methamphetamine (Kinner and Degenhardt, 2008).

Dependent users showed a number of unique statistics that differ from the general population. Four articles looked specifically at groups of methamphetamine dependent individuals. These articles showed a narrower age range of between 30–31.7 (McKetin and Kelly, 2007; McKetin et al, 2008; McKetin et al, 2013; McKetin et al, 2014). These individuals showed slightly higher unemployment rates of between 66–81% (McKetin and Kelly, 2007; McKetin et al, 2008; McKetin et al, 2013; McKetin et al, 2014). Interestingly, they had similar rates of education at both secondary and tertiary levels (McKetin and Kelly, 2007; McKetin et al, 2008; McKetin et al, 2013; McKetin et al, 2014). Periods of homelessness in the last 12 months were significantly higher in dependent methamphetamine users; 40% compared with non-dependent users at 29% (Quinn et al, 2013).

As a summary, most studies agree on a few key points. Users of methamphetamine in Australia are mostly male, aged late twenties to early thirties and born in Australia. They generally have a low level of education, high levels of unemployment and homelessness, and a high rate of dependence on the drug.

Health issues associated with methamphetamine use

An increasing number of individuals are using higher potency crystal methamphetamine compared with powdered methamphetamine and this has been associated with an increase in methamphetamine-related harms (Degenhardt et al, 2017). This is illustrated by a concomitant increase in related drug helpline calls, arrests, hospital admissions and treatment (Degenhardt et al, 2017). In 2013 alone, methamphetamine accounted for an extra 29 700–151 800 presentations to Australian emergency departments (McKetin et al, 2017).

A number of different health issues related to methamphetamine have been identified. Electrocardiograph abnormalities are more common in methamphetamine users (71.7%) than matched controls (32.1%). The drug may also cause other cardiac conditions such as cardiotoxicity, cardiomegaly, coronary vasospasm and aortic dissection (Darke et al, 2008). McKetin et al's paper on associated harms between injecting and smoking methamphetamine users showed that HIV is common in both of these populations (McKetin et al, 2008). It was shown that almost a quarter of injecting users shared or borrowed used needles and similar rates of unprotected casual sex were seen in this population (McKetin et al, 2008). While smoking, users did not experience the risk of infection from needle sharing, they did have significantly higher rates of unprotected sex (McKetin et al, 2008). Roche et al showed that rates of absenteeism in the workforce were significantly greater in methamphetamine users than any other illicit drug users. This trend was seen for injury and illness directly associated to drug use as well as unrelated illnesses (Roche et al, 2008).

Mental health issues are a significant harm linked to methamphetamine use and this was shown across a variety of the studies. Self-reported psychotic illness has a higher prevalence in crystal methamphetamine users (12.0%) compared with users of other forms of methamphetamine (3.9%) (Lappin et al, 2016). In 2013, methamphetamine was responsible for an extra 28 400–80 900 admissions to psychiatric hospitals (McKetin et al, 2017). Wallace et al showed that 43% of non-dependent and 80% of dependent users suffered from a mental disability (Wallace et al, 2009). Quinn et al showed 58% of users had sought professional help from mental health services and 42% were also currently prescribed medications for their mental illness (Quinn et al, 2013). McKetin et al stated that psychosis was common among dependent drug users with 27% experiencing clinically significant episodes (McKetin et al, 2006b). This study also excluded those who had a pre-existing psychiatric condition, thereby indicating the episodes were directly linked to the use of methamphetamine (35). Methamphetamine use in the context of mental health in ageing was explored in a 2015 study. With consideration of the aging population and the prevalence of methamphetamine use, the authors discussed potential challenges for healthcare of the aged in the future. These challenges included chronic neurophysiological and psychiatric conditions as well as issues regarding healthcare for those with a positive immunodeficiency virus status (Searby, 2015).

Causes of death linked to methamphetamine use were identified in a number of studies. Kaye et al released a study specifically focused on fatalities related to methamphetamine use (Kaye et al, 2008). This study identified that in almost all fatalities multiple drugs were used, the most common of which were benzodiazepines and morphine. Almost all deaths were accidental with only 14% being determined to be suicide. The majority of fatalities could be directly attributed to methamphetamine toxicity. Roxburgh and Burns (2015) reported on methamphetamine-related drug deaths in Australia in 2011. The rate of methamphetamine-related deaths for those aged 15–54 years was 8.1 per million persons, which was an increase from 7.1 in the previous year, with a projected increase in this rate for subsequent years. Fatovich, Davis and Bartu noted four deaths in their study of hospitalisations related to amphetamine use (Fatovich et al, 2012). The causes were due to drug toxicity, cardiomegaly, seizure disorder, and the final death was due to multiple organ failure secondary to pneumonia.

Pre-hospital and emergency presentations of methamphetamine use

Hospital presentations from methamphetamine use have increased in recent years and this is linked to a number of issues unique to methamphetamines (Stafford and Breen, 2016). Gray et al showed in 2007 that 1.2% of the workload of Royal Perth Hospital was causally related to amphetamine use (Gray et al, 2007). The most common reason for admission to hospital was agitated delirium and psychosis, followed by assault and other injury. These patients were often aggressive and 32% of the patients included in the study required sedation. A study by Fatovich, Davis and Bartu likewise found that mental disorders were the foremost reason for admission to hospital (Fatovich et al, 2012). This was followed by injury and poisoning, which mirrors Gray et al's findings. An article written by O'Neill, Rawlins and Wood outlined the dangers of methamphetamine lab explosions (O'Neill et al, 2011). While this was a small population, 9 patients over a 12-month period, it gave some important insights into patient behaviour in hospital. The study showed over half of the patients were discharged early due to threatening and antisocial behaviour which was compromising safety of hospital staff. This validates and highlights the findings from Gray et al that methamphetamine cases in hospital are associated with high rates of sedation (Gray et al, 2007). Ali et al similarly recommended judicious use of sedatives as a first line treatment for psychosis for methamphetamine users (Ali et al, 2010).