SUMMARY AND IMPLICATIONS

Demographics
Findings from the 2011 WA IDRS demonstrate little change from last year’s sample in most areas and in others, some significant changes in drug use patterns and perceptions among IDU in Perth. Despite a smaller sample than in previous years, the demographic characteristics of the 2011 WA IDRS sample were mostly similar to the 2010 sample. However, there were significant differences observed in the average age of the 2011 sample, which has been significantly increasing since 2009; from 35 years in 2009, 37 years in 2010 and to an average age of 40 years in 2011. This trend suggests an ageing sample of regular injecting drug users in the WA IDRS, although this could in part reflect the high proportion of the sample recruited from the WA Substance Users Association (WASUA).;If the increasing age does reflect actual changes in the injecting population in Perth then this has implications for health strategies focused towards an aging cohort of injecting drug users. The implications of an ageing IDU population have been addressed in a number of countries (O’Kelly & O’Kelly, 2012) and we recommend further research is conducted on the ageing injecting drug users in WA.

There were also some notable changes between samples regarding tertiary education, with a greater proportion of the 2011 IDRS sample reporting completion of university/college qualifications than in 2010. . It is unknown why the current sample of IDU appears to be more tertiary educated than the 2010 sample.

Another noted demographic change in the 2011 IDU sample was that more than half (59%) of the current sample were currently engaging in drug treatment. Although this current treatment proportion was not significantly different to the 2010 sample, this proportion represented the greatest percentage currently engaging in drug treatment since WA IDRS data collection began. It may be important to note that prior to 2009, a maximum of one-third of the entire IDU sample recruited could be in drug treatment at the time of interview. However, since 2009, this treatment ceiling has been waived in all IDRS jurisdictions, allowing for no upper limit on the proportion of IDU in current drug treatment.

Heroin
Findings from previous years’ WA IDRS samples have observed changing trends in heroin use patterns, which has mostly been explained by continuous shifts in heroin availability and purity. In 2011 patterns of heroin use and frequency of use were mostly comparable to 2010 findings, suggesting some stability currently among IDU who use heroin. However, a significant increase was observed in the proportion reporting current heroin availability as ‘very difficult’ to obtain. In regards to homebake use in the 2011 IDRS sample, a significant increase was observed in the proportion of current IDU reporting recent use of homebake.

As homebake is often sourced as a substitute for heroin, it may be that fluctuations in heroin availability in 2011 may have led to increase homebake use. Further research on this issue is needed.

The median price of one quarter of a gram of heroin significantly increased in 2011; however, there was no significant difference in the price of any other quantity of the drug. Still, the price of heroin still remains more expensive in WA than prior to the heroin shortage in 2001. Heroin purity appears to have remained modest in WA, with perceptions of purity both currently and changes to purity remaining mostly stable in 2011. Overall, reports on heroin by 2011 WA IDU suggest that heroin use has been stable over the last two sample years’.

Methamphetamine
In 2011, there were no other significant differences in the proportion reporting lifetime and recent use of most methamphetamine forms, the only exception being recent use of crystal methamphetamine which significantly increased in 2011. Average number of days of use for any methamphetamine form significantly decreased from 2010 to 2011, as did the average number of days crystal was reportedly used in 2011. This suggests that more IDU in 2011 had used crystal in the past six months; however, the frequency of use was less than in 2010.

However, overall methamphetamine use among IDU samples recruited in Perth appears to be decreasing over time, a trend seen in a number of the indicators since 2007. The other methamphetamine price, purity and availability proportions remained mostly comparable to those observed in 2010; the only exception was a significant increase observed in the median price of a point of speed and in the perceived purity of speed as ‘high’ in 2011. This may suggest the presence of a higher purity and possibly more expensive form of speed methamphetamine available in the Perth drug market at the time of data collection.

Non-fatal overdose
In 2011, lifetime history of heroin overdose was reported by 64% of the 2011 sample, even though this was not a significant increase from 47% in 2010, this current proportion represents the greatest percentage reporting lifetime overdose on heroin since 2000. Additionally, the proportion reporting recently overdosed in the last 12 months significantly increased from 2010. Despite 2011 IDU reporting patterns of heroin use and markets as mostly unchanged since 2010, self-reported accidental lifetime and recent heroin overdose proportions increased. It is uncertain why this discrepancy has occurred, although the selfreport of overdoses by participants within the IDRS, may be more sensitive to trends in current heroin purity in Perth than the purity of a non-random selection of heroin seizures analysed by police in the same period. Supportive of this, a number of Key Experts who commented in 2011 reported on the presence of a number of high purity batches of heroin during the year and suggested that as a consequence, a greater number of regular heroin users were accidentally overdosing.

Further, ambulance data indicated that the number of ambulance callouts to narcotic overdoses in WA has increased significantly in the last five years. However, ambulance callout figures remain far lower than those prior to the heroin shortage. Overdose fatalities in WA remain low compared to the pre-shortage levels, which is probably because, overall, heroin purity appears to remain modest in WA, however there are indications that heroin purity has been fluctuating in recent times.

Overall, these findings reinforces the need to continue to implement the prudent steps already commenced in WA (Rainsford, Lenton & Fetherston, 2010) to prevent heroin overdoses and fatalities. These have included continued monitoring of overdose trend data; reviewing and updating resources and training materials; considering targeting those most at risk of overdose, including people leaving prison and abstinence oriented treatment programs; reviewing protocols regarding police attendance at overdoses; and considering expanding access to naloxone for peer administration (Lenton, Dietze et al. 2009; Lenton, Dietze et al. 2009).

Other opioids and drugs
Significant increases were observed in proportion of the 2011 WA IDRS reporting recent use of illicitly obtained methadone syrup. All other use of illicit pharmacotherapy treatments was reported as comparable to last year, although a significant decrease was observed in the average number of days illicit Suboxone was used in the last six months. This finding may be due to the higher proportion of the 2011 WA IDRS sample currently engaged in drug treatment. It is important to recall that the individuals participating in the IDRS are selected on the basis of their regular injection of drugs and, as such, are not representatives of all those enrolled in maintenance pharmacotherapy programs. Overall, development and implementation of strategies to reduce diversion of and non-adherence with prescribed pharmaceutical opioids are warranted.

There was a significant increase in the proportion of the sample who had used oxycodone in the last six months in the 2011 sample compared to the previous year’s sample. Conversely, the average number of day’s illicit oxycodone was injected in the last six months significantly decreased from last year. In 2011, all participants reporting use of illicit oxycodone in the last six months reported injecting. Clearly, there are potential risks associated with illicit, intravenous use of prescribed medications intended for oral administration. In particular, problems with oxycodone use have been well documented in North America and elsewhere, and this needs to continue to be closely monitored in Australia (Drugs and Crime Prevention Committee, 2007).

In 2011, only one participant reported recent use of ecstasy, which was a significant decrease from 21% in 2010, which is consistent with other indicators that ecstasy use and availability was low in Perth during time of interview. Although, the IDRS is not designed to monitor trends in ecstasy and related drug use as the frequency and prevalence of use among IDU has always been low. For more information on ecstasy trends in Perth, see the 2011 WA EDRS report.

Injecting risk behaviours
Self-reported rates of sharing of needles and syringes among IDU participants have steadily declined over time, with 7% of the current cohort reported use of another person’s used needle/syringe in the month prior to interview. Similarly, the number of participants reporting providing their used equipment to another person was 36% in 2010 compared to 17% in 2011; however, this was not a significant decrease. In 2011, participants were asked for the first time what injecting equipment they had re(?)-used in the last month, of those who commented (n=60), 42% reported the re-use of 1ml needles and syringes and 37% reported cleaning then re-using 1ml needle/syringes. Re-use of injecting equipment increases the risk of inadvertent sharing of other’s equipment. Given these levels of injection-related risk-taking behaviour, risk of transmission of HCV and HIV remains a concern. Therefore, continuing education is necessary to inform IDU of the dangers of sharing injecting equipment. Furthermore, further exploration of the reasons why people re-use their own equipment needs to be identified. In the past cost of equipment was identified as a significant contributor to decisions to re-use. In general terms, the results also reinforce the ongoing need for readily available access to clean needles.

Mental health problems and psychological distress
Just under half (44%) of the current sample reported having experienced a mental health problem in the six months prior to interview. As in previous years, depression and anxiety were the most commonly reported mental health problems. Participants were considerably more likely to score in the ‘high’ or ‘very high distress’ categories than the general Australian population as measured by the Kessler Psychological Distress Scale (K10) (38% vs. 9%). In 2011, the SF-12 was included to assess the mental and physical health of IDU. Participants in the 2011 WA IDRS scored a significantly lower mental component score and physical component score than the Australian population, indicating that IDRS participants had poorer mental and physical health then the average population. These data suggest the need for strategies to improve the mental and physical health of people who inject drugs.

Driving risk behaviour
The vast majority of IDU reported driving under the influence of illicit drugs and most perceived this to have no impact on their driving ability. Thus, the provision of accurate information about the impact of drugs on driving ability is needed. Providing information through needle exchanges, and on fitpacks sold through community pharmacies as well as at the point of roadside drug testing may be some opportunities for addressing this issue.

Heavy smoking index for nicotine dependence
Among those who reported daily smoking (77%), just over one-third of daily smokers scored 5 or above indicating high nicotine dependence. Within health care or treatment settings, nicotine addiction is sometimes overlooked as a primary drug of concern among injecting drug users, despite the fact that tobacco use is the largest preventable cause of death and disease in Australia. An increased emphasis on providing targeted interventions and suited pharmacological management for IDU who smoke tobacco is warranted to help drug injectors quit smoking.