Objective: We aimed to (i) describe the 10-year trend in admissions associated with amphetamine use, (ii) describe the distinguishing characteristics of people with an amphetamine-related diagnosis (ARD) and (iii) examine predictors of repeated admissions among people with an ARD. Method: We conducted a retrospective cohort study. We (i) counted the number of admissions with an ARD and evaluated any trends, and using univariate and multivariate tests, (ii) compared those who had an ARD with those who did not and (iii) compared those with an ARD who had one, two to four, and five or more admissions. Results: Admissions associated with amphetamine use increased between 2009 and 2015. Those with an ARD had significant differences in demographics, diagnosis and pattern of service use relative to those without an ARD. Amongst those with an ARD, a higher number of admissions was positively associated with a schizophrenia diagnosis but inversely associated with a transient psychotic disorder diagnosis. Conclusions: The increase in admissions associated with amphetamine use indicates that people with an ARD posed major demands on inpatient services. Targeting amphetamine treatment to those with psychotic disorders, both schizophrenia and transient psychotic disorders, may reduce hospital-related costs and re-admissions.

Results suggest that even where cleaning of needles and syringes is widespread, people who inject drugs may not engage in efficacious cleaning. The combination of the complexity of current cleaning messages and a lack of accurate information about efficacious techniques are likely to contribute to poor cleaning practice. Australia could benefit from the development of a nationally consistent cleaning message; however, the evidence would suggest that this would need to be accompanied by strategies designed to simplify and disseminate this information in order to increase the uptake of efficacious cleaning methods by people who inject drugs.