Poly drug use
Cannabis use is also highly correlated with the use of tobacco, alcohol and other drugs. This makes measuring the effects of cannabis alone difficult and potentially increases risks for users.
The 2019 NDSHS showed that alcohol was the most common substance used concurrently with cannabis. Of those recent cannabis users who also consumed alcohol, 62% exceeded the single occasion risk guidelines at least monthly and 39% exceeded the lifetime risk guidelines (Table S2.68).
The most common other drugs concurrently used by recent cannabis users were:
- tobacco (29%)
- cocaine (25%)
- ecstasy (19.7%),
- the non-medical use of pharmaceuticals (14.1%) (Table S2.68).
In 2019, there were 206 drug-induced deaths where cannabinoids were present (Table S1.1). Compared with other licit and illicit drugs, cannabinoids are less frequently present in drug-induced deaths (Table S1.1). However, cannabis was the second most common drug identified at toxicology for transport accident deaths (ABS 2017). The short-term effects of cannabis can increase the risk of road traffic crashes, largely due to diminished driving performance in response to emergencies (Hall & Degenhardt 2009).
Hospitalisations
The National Hospital Morbidity Database showed that in 2018–19, the rate of drug-related hospital separations for cannabinoids was similar for people usually residing in Major cities (22.8 per 100,000 population) and Regional and remote areas (26.5 per 100,000 population). However, the rate was highest for people usually residing in Remote and very remote areas (56.3 per 100,000 population (Table S1.8c).
Ambulance attendances
Data on alcohol and other drug-related ambulance attendances are sourced from the National Surveillance System for Alcohol and Other Drug Misuse and Overdose report. Data for 2019 are available for New South Wales, Victoria, Tasmania and the Australian Capital Territory. Data are presented for 4 snapshot months per year, specifically March, June, September and December. Please see the data quality statement for further information.
The rate of cannabis-related ambulance attendances ranged from 20.2 per 100,000 population in New South Wales to 28.1 per 100,000 population in Tasmania.
The majority of cannabis-related attendances were for males, ranging from 58% of attendances in the Australian Capital Territory to 66% of attendances in New South Wales. The median age for cannabis-related attendances was similar across jurisdictions, ranging from 28 years in New South Wales to 31 years in the Australian Capital Territory.
Higher rates for cannabis-related ambulance attendances were reported in regional areas for New South Wales (22.4 per 100,000 population compared with 19.2 for metropolitan areas) and Victoria (25.6 per 100,000 population compared with 20.7 for metropolitan areas). However, in Tasmania the rate for these attendances was higher for Greater Hobart (31.9 per 100,000) than for Regional Tasmania (25.1 per 100,000). Similar proportions of cannabis-related attendances were transported to hospital in metropolitan and regional areas for New South Wales (84% and 81%, respectively), Victoria (80% and 83%, respectively) and Tasmania (77% and 74%, respectively) (Table S2.81) (Moayeri et al. 2020).
Treatment
Data collected for the AODTS NMDS are released twice each year—a key findings report in April and a detailed report in June. Detailed information about closed treatment episodes for cannabis will be updated in June 2021.
The 2018–19 AODTS NMDS showed that cannabis was the principal drug of concern for clients’ own drug use in 19.8% of closed treatment episodes, and was the third most common principal drug overall (Table S2.76; Figure CANNABIS3).
- Client demographics where cannabis was the principal drug of concern:
- Almost 7 out of 10 clients were males (68%) (Table S2.77), and around 1 in 6 were Indigenous (18.8%) (Table S2.78).
- Indigenous Australians (927 per 100,000 population) were more likely to have received treatment than non-Indigenous Australians (116 per 100,000 population) (AIHW 2020a).
- Source of referral for treatment:
- The most common source of referral for treatment where cannabis was the principal drug of concern was diversion (that is, referred from the criminal justice system into AOD treatment for drug or drug-related offences) and self/family (both 28% of treatment episodes) (Table S2.79).
- Treatment type:
- Where cannabis was the principal drug of concern, counselling was the most common treatment type (38% of treatment episodes), followed by information and education only (20%) (Table S2.80).
- The median treatment length for closed treatment episodes where cannabis was the principal drug of concern was 17 days.