Drug and Alcohol Elsevier Scientific
Dependence, 31 (1992) 31-36 Publishers Ireland Ltd.
Benzodiazepine
Shane
31
use and HIV risk-taking injecting drug users
Darke”,
Wayne
Hall”, Michael
behaviour
Rossb and Alex Wodak”
aNational Drug and Alcohol Research Centre, bNational Centre in HIV Social Research, University ‘Alcohol and Drug Service, St Vincent’s Hospital, Kensington, NSW (Australia)
(Accepted
March
among
of Nm
South Wales,
5th, 1992)
This paper examines the prevalence of benzodiazepine use, and its relationship to other drug use and HIV risk-taking among a sample of 1245 injecting drug users (IDU). Approximately a third (36.6%) of the sample had used benzodiazepines during their last typical month of injecting. Benzodiazepine users had injected more frequently, injected more heroin and amphetamines, and had more poly-drug use than other IDU. They also had higher levels of HIV risk-taking, having shared injecting equipment more frequently and with more people. There were no differences between groups in number of sexual partners or condom use, although benzodiazepine users were more likely to have been paid for sex. The demographic and drug use variables indicate that benzodiazepine users are a more dysfunctional subgroup of IDU who require particular attention in HIV interventions. Key words: HIV; benzodiazepines,
injecting
drug
users;
behaviour;
Introduction
IDU are of particular interest in relation to HIV as they occupy a pivotal role in terms of virus transmission. IDU may transmit HIV to other IDU through shared injecting equipment or sexual behaviour, to their children through perinatal transmission and to the broader nonIDU heterosexual population by means of sexual transmission. As regards injecting behaviour, high incidences of needle sharing have been consistently reported in the United States, Europe and Australia (e.g., Darke, Hall and Carless 1990, Lishner and Look 1990, Rahman, Ditton and Forsyth 1989, Sasse, Contis et al. 1989). Despite the fact that IDU are at particular risk of sexual transmission of the virus, condom use among this group has been repeatedly found to be extremely low, particularly with regular sexual partners (e.g., Donoghoe, Stimsom and Dolan 1989, Feucht, Stephens and Roman 1990, Darke, Hall and Carless 1990, Klee et al. 1990a, Ross, Wodak, Gold and Miller, in press). A substantial proportion of IDU engage in prostitution to generate income for their continuing
The relationship between injecting drug users (IDU) and the Human Immunodeficiency Virus (HIV) is well documented. IDU are currently the second largest risk group of diagnosed AIDS cases in Europe and the United States (World Health Organization/Centers for Disease Control 1991, Des Jarlais, Friedman and Casriel 1990). Overall, 32% of AIDS cases reported in the United States by June 1991 had injecting drug use as an associated risk factor (WHO/CDC 1991). In Australia injecting drug use has been reported as a single or combined risk factor in 4% of AIDS cases (National Centre in HIV Epidemiology and Clinical Research 1991). The seroprevalence among IDU is estimated to be between 3-5% (Morlet, Darke, Guinan et al. 1989, Ross, Wodak, Gold and Miller, 1991). Correspondence to: Shane Darke, National Drug and Alcohol Research Centre, University of New South Wales, Kensington, NSW, Australia.
0376-8716/92/$05.00 Printed and Published
0 1992 Elsevier in Ireland
Scientific
Publishers
AIDS
Ireland
Ltd.
32
drug use, thus providing a conduit to the broader community (Philpot, Harcourt and Edwards 1989, Des Jarlais et al. 1987, Saxon et al. 1991). Recently, evidence is emerging that the prevalence of both risk-taking and HIV among IDU may, in part, be related to the type of drug(s) the person is using (e.g., Batki, Sorenson, Gibson and Maude-Griffin 1989, Chaisson, Bacchetti, Osmond et al. 1989, Darke, Baker, Dixon, Wodak and Heather, 1992; Klee, Faugier, Hayes, Bolton and Morris 1990b, Metzger, Woody, DePhillipis et al. 1991, Torrens, Sans, Peri and Olle, 1991). In particular, the use of two major drug classes, cocaine and benzodiazepines, have been associated with increased parenteral risk-taking behaviour and a higher seroprevalence. Chaisson et al. (1989) found cocaine use to be strongly associated with seropositivity, more frequent injections, more frequent sharing, and more frequent use of shooting galleries. Data consistent with the existence of an association between cocaine injecting and HIV risk taking has also been found in both Europe and Australia (Darke et al. 1992, Torrens et al. 1991). Two studies to date have related benzodiazepine use to HIV risk-taking behaviour in both Britain and the United States (Klee et al. 1990b, Metzger et al. 1991) found the use of the benzodiazepine temazepam to be associated with significantly more sharing (both lending and borrowing) equipment in the 6 months preceding interview and that users of temazepam had shared more recently than those IDU who had not used temazepam. The authors suggest that factors such as short-term memory loss and/or disinhibitionresulting from intoxication with the drug may be responsible for the observed relationship. Metzger et al. (1991) also reported a relationship between benzodiazepine use and HIV risk-taking among IDU, with those subjects who had shared equipment in the preceding 6 months having significantly higher rates of benzodiazepine use than non-sharers. The current study aimed to examine the relationship between injecting drug use and benzodiazepine use among a large Australian sample
of IDU. Specifically, the paper addressed the following questions: (1) What is the prevalence of benzodiazepine use among injecting drug users? (2) Can benzodiazepine users be distinguished from other IDU by their sociodemographics, patterns of injecting and other drug use? (3) Do benzodiazepine users engage in more risky injecting and sexual behaviour than other IDU? Method Subjects
A total of 1245 IDU were interviewed, consisting of 908 males, 331 females and 6 male to female transsexuals. The mean age of the sample was 27.5 years. IDU from all geographic regions of Sydney were represented in the sample, with the largest groups coming from the inner city and eastern suburbs (52.5%) and the western suburbs of Sydney (30.8%). Less than 1 in 5 (17.7%) of the sample were in full or parttime employment, with the majority (77.3%) deriving their income from social security. These demographic characteristics are similar to those of other Australian, British, European and American studies of injecting drug users (e.g., Klee et al., 1990a, Morlet et al., 1990, Sasse et al. 1989). The majority of the sample (62.3%) had been in some form of drug treatment. The most common form of service contact had been with detoxification or methadone withdrawal (47.9%), followed by methadone maintenance (20.2%), inpatient rehabilitation programs (11.6%), outpatient counselling (9.9%) and therapeutic communities (8.5%). The characteristics of the sample are more fully described elsewhere (Ross et al. 1991). Procedure
The study questions were addressed by using data collected during the Sydney arm of the Australian National AIDS and Injecting Drug Users Study (ANAIDUS), which surveyed IDU about their drug use, needle-sharing and sexual practices. In the Sydney arm of the study, injecting drug
33
users were solicited for interview by distributing cards with details about the study, advertisements in employment and social security exchanges, needle-exchanges, pharmacies which sold syringes and in a free popular inner city newspaper. Interviews took place in an unmarked building in an inner city neighbourhood associated with the Sydney drug using subculture. Subjects had direct and discreet access to the study off the street where they were seen by a receptionist who took their initials and date of birth and ensured that no double interviewing occurred. Interviews were conducted in private by interviewers who had extensive personal or professional experience with injecting drug use and who were trained and supervised by one of the authors (M.R.). Interviews were also conducted in the western suburbs of the city to obtain a broader geographic representation of injecting drug users. Subjects were paid A$20 for their participation in the study. The interview schedule, which had been pilot tested on 100 drug users, took approximately 75 min to complete. It contained sections on demographics; drug treatment and incarceration history; drug use behaviour (including drug types used, frequency of injection and ingestion of 18 drug types); patterns of needle use and reuse (including purchase, sharing, cleaning and disposal); the social context of injecting drug use; sexual history (including sexual practices and preference, STDs, prostitution); knowledge of and attitudes towards HIV; behaviour change in response to HIV (both sexual and injecting behaviour); and information sources (printed and electronic media) that were regularly used. Subjects’ pattern of drug use was assessed by asking how old they were when they first injected a drug, how long it had been since they last injected, how often they injected in a ‘typical month’ and how old they were when they began to inject once a month or more. They were then asked whether they had ever used each of 18 drug types: seven opioid drugs (heroin, methadone, morphine, opium, pethidine, codeine and palfium), amphetamines, LSD, ‘ecstasy’ (MDMA), cocaine, crank, crack, bar-
biturates, benzodiazepines, alcohol, cannabis and nicotine, whether they had injected, or ingested (smoked, snorted, or swallowed) them; and how often they had done so in a ‘typical using month’. For those currently in treatment, a ‘typical using month’ was that prior to the commencement of treatment. Results Benxodiaxepine
use
A total of 456 (36.6%) of subjects reported using benzodiazepines in their last typical month of injecting drug use, 266 (21.4%) reporting daily use during that period and 190 (15.3%) less than daily use. Demographic
comparisons
The mean age of benzodiazepine users was significantly younger than that of the rest of the sample (26.8 years vs. 27.9; t = 2.80, d.f. = 1240, P < 0.005). Females were more likely than males to report benzodiazepine use (odds ratio O.R. 1.32, 95% C.I. 1.02-1.71, P c 0.05).
Benzodiazepine users were also significantly more likely than other IDU to be currently unemployed (O.R. 1.80, 95% C.I. 1.41-2.30, P < O.OOl), more likely to have not completed high school (O.R. 1.38, 95% C.I. 1.09-1.75, P c 0.01) and more likely to have been imprisoned (O.R. 1.34, 95% C.I. 1.05-1.70, P < 0.05). Drug use comparisons
The mean age of first injecting drug use reported by benzodiazepine users was significantly younger than that of the rest of the sample (18.0 years vs. 18.4; t = 2.96, d.f. = 1241, P < 0.005), as was the age of first regular injecting drug use (19.3 vs. 20.0, t = 2.46, d.f. = 1199, P c 0.01) (Table I). Benzodiazepine users reported significantly more injections during the last typical month of use (60.3 vs. 51.8, t = 2.21, d.f. = 1227, P c 0.05). Benzodiazepine users also reported having used significantly more drug classes in their life than other IDU (12.2 vs. 11.5, t = 3.03,
34
Table I. Injecting other IDLJ.
behaviour
Lifetime Age 1st injection Age regular injecting No. drug classes No. drug classes (injected) Typical month Heroin injections Amphetamines injections Cocaine injections Frequency shared Number shared with Intoxicated when used Never cleaned equipment Always cleaned equipment
of benzodiazepine
users
Benzodiazepine users
Other
18.0
19.3 12.2 4.8
18.4 20.0 11.5 4.7
46.3 13.4
29.4 7.5
6.7 21.3% 2.6 49.0% 6.5%
6.0 17.4% 1.3 43.2% 5.4%
83.6%
87.5%
and
IDU
df. = 1243, P < 0.005), although there was no significant difference in the mean number of drug classes which had been injected (4.8 vs. 4.7). Benzodiazepine users reported significantly more injections of heroin (46.3 vs. 29.4, t = 5.12, d.f. = 1243, P < 0.001) and amphetamines (13.4 vs. 7.5, t = 3.6, d.f. = 1242, P < 0.001) during the last typical month of use. There was no significant difference in the mean number of cocaine injections between the with both groups reporting a low groups, frequency of injection (6.7 vs. 6.0). HIV Risk-taking comparisons Benzodiazepine users reported a significantly greater frequency of injecting with borrowed equipment (21.3% of the time vs. 17.4%, t = 2.51, d.f. = 1165, P < 0.01) and had shared injecting equipment with significantly more people than other IDU in the 6 months preceding interview (2.6 vs. 1.3, t = 3.12, d.f. = 1295, P < 0.005). Benzodiazepine users were not significantly more likely than other IDU to have
ever shared equipment with a person they knew was HIV positive, although this comparison narrowly missed out on achieving significance (O.R. 1.97, 95% C.I. 0.97-3,97, P < 0.06). Benzodiazepine users reported a significantly higher proportion of injections as occurring while being ‘stoned, high, or drunk’ than other IDU (49.0% vs. 43.2%, t = 2.99, d.f. = 1224, P < 0.005). The proportions of benzodiazepine users and other IDU who never cleaned their injecting equipment (6.5% vs. 5.4%) and those who always cleaned (83.6 vs. 87.5) were not significantly different. The sample as a whole was sexually active, with 94.5% of subjects having had sex in the year preceding interview (Table II). The majority of subjects (72.9%) reported more than one partner during this time. The median number of partners for the sample was three. Benzodiazepine users were no more likely than other IDU to report multiple partners. Benzodiazepine users were, however, 1.76 times more likely
Table II. Sexual other IDU.
behaviour
of benzodiazepine
Benzodiazepine users Number of partners 0 1 >1 Median
25
(5.5%)
93 (20.4%) 570 (74.1%) 4
Condom use (all partners) Vaginal sex: Never 149 (38.4Yu) Always 48 (12.4%) Anal sex: Never 41 (46.1%) Always 15 (16.9%) (Regular partners) Vaginal sex: Never Always Anal sex: Never Always
users
Other
and
IDU
43 (5.5%) 176 (22.3%) 570 (72.2%) 3
242 (36.6%) 65 (9.8%) 15 (16.9%) 28 (20.0’10)
157 (47.9%) 26 (7.9%)
293 (49.4%) 41 (6.9%)
36 (55.3%) 7 (10.8%)
66 (51.6%) 19 (14.9%)
35
than other IDU to report having engaged in prostitution (95% C.I. 1.24-2.48, P < 0.001). Condom use was extremely low among both groups (Table II). There were no significant differences in the frequency of condom use between groups for either vaginal or anal sex. There was a small but significant difference between the groups in the number of sexually transmissible diseases ever reported, with benzodiazepine users reporting more diseases (0.7 vs. 0.5, t = 2.38, d.f. = 1235, P < 0.05). Despite their generally higher levels of risktaking behaviour, seronegative benzodiazepine likely than other were no more users seronegative IDU to state that they had a reasonably good chance of contracting HIV (defined as 10% or greater): 25.4% of benzodiazepine users vs. 22.0% of other IDU. Large proportions of both groups thought that they had either no chance of a one in a million chance of contracting HIV (27.5% of benzodiazepine users vs. 28.5% of other IDU). The groups were not significantly different in this perception. Discussion
Benzodiazepine use was widespread amongst subjects in this sample of IDU. Overall, 36.6% of IDU in this study reported using benzodiazepines during their last typical month of injecting drug use, with a fifth of subjects reporting daily use. Given the associations between benzodiazepine use and injecting drug use found in this study, the high prevalence of benzodiazepine use is cause for concern. Benzodiazepine users injected more frequently in a typical month, injected heroin more often and, surprisingly given contradictory pharmacological effects, injected amphetamines more frequently than other IDU. They had also had significantly more poly-drug use than other IDU. This pattern of use may suggest that benzodiazepine users are seeking intoxication as such, rather than the effects of a particular drug. In addition to injecting more frequently than other IDU, benzodiazepine users also engaged in significantly more HIV risk-taking. In relation to injecting behaviour, benzodiazepine users
shared injecting equipment more frequently and shared with more people than did other IDU. These findings from an Australian sample are consistent with those of studies conducted in the United States (Metzger et al. 1991) and Britain (Klee et al. 1990b). One possible factor which may be related to these behaviours is the finding that benzodiazepine users reported being ‘stoned, high or drunk’ more often when they were injecting than did other IDU. This may contribute to either disinhibition or short-term memory loss, increasing the probability of risky behaviour . In contrast to injecting behaviour, benzodiazepine users did not differ from other IDU in number of sexual partners or condom use. For both groups multiple partners were the norm and condom use was extremely low. The latter finding is consistent with other studies (e.g., Klee et al. 1990a; Sasse et al., 1989). Benzodiazepine users were, however, 1.76 times more likely than other IDU to have engaged in prostitution. This may be a reflection of the cost of their more frequent drug use, thus increasing the likelihood of prostitution to support continued drug use. Despite the fact that benzodiazepine users were engaging in more risk-taking behaviour than other IDU, they did not see themselves at more risk for contracting HIV than other IDU. In fact, over a quarter of benzodiazepine users rated their risk at zero or one in a million. Clearly, the risk perception of this group does not accord with their actual behaviour. If behaviour change is to be achieved amongst this group, attention must be paid to altering their risk perception. Overall, the demographic and drug use profiles benzodiazepine users would appear to indicate that they are a more dysfunctional sub-group of IDU. They commenced injecting earlier than other IDU, were more likely to be unemployed, are less educated and more likely to have been imprisoned, inject more frequently, have more poly-drug use, share needles more frequently and with more people. Clearly interventions aimed at reducing risk-taking among IDU need to pay particular attention to this sub-group.
36
In summary, this study found a high prevalence of benzodiazepine use among IDU and that the use of benzodiazepines was associated with more HIV risk-taking. The demographic and drug use profiles of this group indicate them to be a more dysfunctional group of IDU. In terms of HIV risk-taking and the consequent spread of HIV, benzodiazepine users are a group which require particular attention. Acknowledgments
This research was funded by a Commonwealth AIDS Research Grant and the National Campaign Against Drug Abuse. References Batki, S.L., Sorenson, J.L., Gibson, D.R. and Maude-Griffin, P. (1989) HIV infected IV drug users in methadone treatment: outcome and psychological correlates. In: A Preliminary Report: Problems of Drug Dependence (Harris, L.S., ed.), NIDA Research Monogr. 95. Chaisson, R.E., Bacchetti, P., Osmond, D., Brodie, B., Sande, M.A. and Moss, A.R. (1989) Cocaine use and HIV infection in intravenous drug users in San Francisco. J. Am. Med. Assoc. 261, 561- 565. Darke, S., Baker, A., Dixon, J., Wodak, A. and Heather, N. (1992) Drug use and HIV risk-taking behaviour among clients in methadone maintenance treatment. Drug Alcohol Depend. 29, 263-268. Darke, S., Hall, W. and Carless, J. (1990) Drug use, injecting practices and sexual behaviour of opioid users in Sydney, Australia. Br. J. Addict. 85, 1603 - 1609. Des Jarlais, D.C., Friedman, S.R. and Casriel, C. (1990) Target groups for preventing AIDS among intravenous drug users: 2. The hard data studies. J. Consult. Clin. Psychol. 58, 50-56. Des Jar&s, D.C., Wish, E., Friedman, S.R., Stoneburner, R.L., Yankovitz, F., Mildban, D., El-Sadr, W., Brady, E. and Cuadrado, M. (1987) Intravenous drug users and the sexual transmission of the acquired immunodeficiency syndrome. N.Y. State J. Med. 87, 283-286. Donoghoe, MC., Stimson, G. and Dolan, H.A. (1989) Sexual behaviour of injecting drug users and associated risks of HIV infection for non-injecting sexual partners. AIDS Care 1, 51-58.
Feucht, T.E., Stephens, R.C and Roman, S.W. (1990) The sexual behaviour of intravenous drug users: assessing the risk of the sexual transmission of HIV. J. Drug Issues 20, 195-213. Klee, H., Faugier, J., Hayes, C., Boulton, T. and Morris, J. (1990a) Sexual partners of injecting drug users: the risk of HIV infection. Br. J. Addict. 85, 413-418. Klee, H., Faugier, J., Hayes, C., Boultcn, T. and Morris, J. (1990b) AIDS-related risk behaviour, polydrug use and temazepam. Br. J. Addict. 85, 1125-1132. Lishner, D.M. and Look, M.S. (1990) Needle sharing practices and risk for AIDS transmission among intravenous drug users in Seattle. Int. J. Addict. 25, 1475 - 1483. Metzger, D., Woody, G., DePhilipis, D., McLellan, A.T., O’Brien, C.P. and Platt, J.J. (1991) Risk factors for needle sharing among methadone treated patients. Am. J. Psychiatr. 48, 636 - 640. Morlet, A., Darke, S., Guinan, J.J., Wolk, J. and Gold, J. (1990) Intravenous drug users who present to the Albion St. (AIDS) Centre for diagnosis and management of human immunodeficiency virus infection. Med. J. Australia 152, 78 - 80. National Centre in HIV Epidemiology and Clinical Research (1991) Cumulative analysis of AIDS cases in Australia. Philpot, C.R., Harcourt, C.L. and Edwards, J.M. (1989) Drug use by prostitutes in Sydney. Br. J. Addict. 84, 499 - 505. Rahman, M.Z., Ditton, J. and Forsyth, J.M. (1989) Variations in needle sharing practices among intravenous drug users in Possil (Glasgow). Br. J. Addict. 84, 923-927. Ross, M.W., Gold, J., Wodak, A.D. and Miller, M.E. (1991) Sexually transmissible diseases in injecting drug users. Genitourinary Med. 67, 32 - 36. Ross, M.W., Wodak, A.D., Gold, J. and Miller, M.E. Sexual behaviour in injecting drug users. J. Psychol. Human Sexuality (in press). Sasse, H., Salmaso, S., Contis, S. and the First Drug User Multicentre Study Group (1989) Risk behaviours for HIV-I in Italian drug users: report from a multicentre study. J. AIDS 2, 486-496. Saxon, A.J., Calsyn, D.A., Whittaker, S. and Freeman, G. (1991) Sexual behaviours of intravenous drug users in treatment. J. AIDS 4, 938-944. Torrens, M., San, L., Peri, J.M. and Olle, J.M. (1991) Cocaine abuse among heroin addicts in Spain. Drug Alcohol Depend. 27, 29-34. World Health Organization and the Centers for Disease Control (1991) Statistics from the World Health Organization and the Centers for Disease Control. J. AIDS, 5, 1399-1403.
Dependence, 31 (1992) 31-36 Publishers Ireland Ltd.
Benzodiazepine
Shane
31
use and HIV risk-taking injecting drug users
Darke”,
Wayne
Hall”, Michael
behaviour
Rossb and Alex Wodak”
aNational Drug and Alcohol Research Centre, bNational Centre in HIV Social Research, University ‘Alcohol and Drug Service, St Vincent’s Hospital, Kensington, NSW (Australia)
(Accepted
March
among
of Nm
South Wales,
5th, 1992)
This paper examines the prevalence of benzodiazepine use, and its relationship to other drug use and HIV risk-taking among a sample of 1245 injecting drug users (IDU). Approximately a third (36.6%) of the sample had used benzodiazepines during their last typical month of injecting. Benzodiazepine users had injected more frequently, injected more heroin and amphetamines, and had more poly-drug use than other IDU. They also had higher levels of HIV risk-taking, having shared injecting equipment more frequently and with more people. There were no differences between groups in number of sexual partners or condom use, although benzodiazepine users were more likely to have been paid for sex. The demographic and drug use variables indicate that benzodiazepine users are a more dysfunctional subgroup of IDU who require particular attention in HIV interventions. Key words: HIV; benzodiazepines,
injecting
drug
users;
behaviour;
Introduction
IDU are of particular interest in relation to HIV as they occupy a pivotal role in terms of virus transmission. IDU may transmit HIV to other IDU through shared injecting equipment or sexual behaviour, to their children through perinatal transmission and to the broader nonIDU heterosexual population by means of sexual transmission. As regards injecting behaviour, high incidences of needle sharing have been consistently reported in the United States, Europe and Australia (e.g., Darke, Hall and Carless 1990, Lishner and Look 1990, Rahman, Ditton and Forsyth 1989, Sasse, Contis et al. 1989). Despite the fact that IDU are at particular risk of sexual transmission of the virus, condom use among this group has been repeatedly found to be extremely low, particularly with regular sexual partners (e.g., Donoghoe, Stimsom and Dolan 1989, Feucht, Stephens and Roman 1990, Darke, Hall and Carless 1990, Klee et al. 1990a, Ross, Wodak, Gold and Miller, in press). A substantial proportion of IDU engage in prostitution to generate income for their continuing
The relationship between injecting drug users (IDU) and the Human Immunodeficiency Virus (HIV) is well documented. IDU are currently the second largest risk group of diagnosed AIDS cases in Europe and the United States (World Health Organization/Centers for Disease Control 1991, Des Jarlais, Friedman and Casriel 1990). Overall, 32% of AIDS cases reported in the United States by June 1991 had injecting drug use as an associated risk factor (WHO/CDC 1991). In Australia injecting drug use has been reported as a single or combined risk factor in 4% of AIDS cases (National Centre in HIV Epidemiology and Clinical Research 1991). The seroprevalence among IDU is estimated to be between 3-5% (Morlet, Darke, Guinan et al. 1989, Ross, Wodak, Gold and Miller, 1991). Correspondence to: Shane Darke, National Drug and Alcohol Research Centre, University of New South Wales, Kensington, NSW, Australia.
0376-8716/92/$05.00 Printed and Published
0 1992 Elsevier in Ireland
Scientific
Publishers
AIDS
Ireland
Ltd.
32
drug use, thus providing a conduit to the broader community (Philpot, Harcourt and Edwards 1989, Des Jarlais et al. 1987, Saxon et al. 1991). Recently, evidence is emerging that the prevalence of both risk-taking and HIV among IDU may, in part, be related to the type of drug(s) the person is using (e.g., Batki, Sorenson, Gibson and Maude-Griffin 1989, Chaisson, Bacchetti, Osmond et al. 1989, Darke, Baker, Dixon, Wodak and Heather, 1992; Klee, Faugier, Hayes, Bolton and Morris 1990b, Metzger, Woody, DePhillipis et al. 1991, Torrens, Sans, Peri and Olle, 1991). In particular, the use of two major drug classes, cocaine and benzodiazepines, have been associated with increased parenteral risk-taking behaviour and a higher seroprevalence. Chaisson et al. (1989) found cocaine use to be strongly associated with seropositivity, more frequent injections, more frequent sharing, and more frequent use of shooting galleries. Data consistent with the existence of an association between cocaine injecting and HIV risk taking has also been found in both Europe and Australia (Darke et al. 1992, Torrens et al. 1991). Two studies to date have related benzodiazepine use to HIV risk-taking behaviour in both Britain and the United States (Klee et al. 1990b, Metzger et al. 1991) found the use of the benzodiazepine temazepam to be associated with significantly more sharing (both lending and borrowing) equipment in the 6 months preceding interview and that users of temazepam had shared more recently than those IDU who had not used temazepam. The authors suggest that factors such as short-term memory loss and/or disinhibitionresulting from intoxication with the drug may be responsible for the observed relationship. Metzger et al. (1991) also reported a relationship between benzodiazepine use and HIV risk-taking among IDU, with those subjects who had shared equipment in the preceding 6 months having significantly higher rates of benzodiazepine use than non-sharers. The current study aimed to examine the relationship between injecting drug use and benzodiazepine use among a large Australian sample
of IDU. Specifically, the paper addressed the following questions: (1) What is the prevalence of benzodiazepine use among injecting drug users? (2) Can benzodiazepine users be distinguished from other IDU by their sociodemographics, patterns of injecting and other drug use? (3) Do benzodiazepine users engage in more risky injecting and sexual behaviour than other IDU? Method Subjects
A total of 1245 IDU were interviewed, consisting of 908 males, 331 females and 6 male to female transsexuals. The mean age of the sample was 27.5 years. IDU from all geographic regions of Sydney were represented in the sample, with the largest groups coming from the inner city and eastern suburbs (52.5%) and the western suburbs of Sydney (30.8%). Less than 1 in 5 (17.7%) of the sample were in full or parttime employment, with the majority (77.3%) deriving their income from social security. These demographic characteristics are similar to those of other Australian, British, European and American studies of injecting drug users (e.g., Klee et al., 1990a, Morlet et al., 1990, Sasse et al. 1989). The majority of the sample (62.3%) had been in some form of drug treatment. The most common form of service contact had been with detoxification or methadone withdrawal (47.9%), followed by methadone maintenance (20.2%), inpatient rehabilitation programs (11.6%), outpatient counselling (9.9%) and therapeutic communities (8.5%). The characteristics of the sample are more fully described elsewhere (Ross et al. 1991). Procedure
The study questions were addressed by using data collected during the Sydney arm of the Australian National AIDS and Injecting Drug Users Study (ANAIDUS), which surveyed IDU about their drug use, needle-sharing and sexual practices. In the Sydney arm of the study, injecting drug
33
users were solicited for interview by distributing cards with details about the study, advertisements in employment and social security exchanges, needle-exchanges, pharmacies which sold syringes and in a free popular inner city newspaper. Interviews took place in an unmarked building in an inner city neighbourhood associated with the Sydney drug using subculture. Subjects had direct and discreet access to the study off the street where they were seen by a receptionist who took their initials and date of birth and ensured that no double interviewing occurred. Interviews were conducted in private by interviewers who had extensive personal or professional experience with injecting drug use and who were trained and supervised by one of the authors (M.R.). Interviews were also conducted in the western suburbs of the city to obtain a broader geographic representation of injecting drug users. Subjects were paid A$20 for their participation in the study. The interview schedule, which had been pilot tested on 100 drug users, took approximately 75 min to complete. It contained sections on demographics; drug treatment and incarceration history; drug use behaviour (including drug types used, frequency of injection and ingestion of 18 drug types); patterns of needle use and reuse (including purchase, sharing, cleaning and disposal); the social context of injecting drug use; sexual history (including sexual practices and preference, STDs, prostitution); knowledge of and attitudes towards HIV; behaviour change in response to HIV (both sexual and injecting behaviour); and information sources (printed and electronic media) that were regularly used. Subjects’ pattern of drug use was assessed by asking how old they were when they first injected a drug, how long it had been since they last injected, how often they injected in a ‘typical month’ and how old they were when they began to inject once a month or more. They were then asked whether they had ever used each of 18 drug types: seven opioid drugs (heroin, methadone, morphine, opium, pethidine, codeine and palfium), amphetamines, LSD, ‘ecstasy’ (MDMA), cocaine, crank, crack, bar-
biturates, benzodiazepines, alcohol, cannabis and nicotine, whether they had injected, or ingested (smoked, snorted, or swallowed) them; and how often they had done so in a ‘typical using month’. For those currently in treatment, a ‘typical using month’ was that prior to the commencement of treatment. Results Benxodiaxepine
use
A total of 456 (36.6%) of subjects reported using benzodiazepines in their last typical month of injecting drug use, 266 (21.4%) reporting daily use during that period and 190 (15.3%) less than daily use. Demographic
comparisons
The mean age of benzodiazepine users was significantly younger than that of the rest of the sample (26.8 years vs. 27.9; t = 2.80, d.f. = 1240, P < 0.005). Females were more likely than males to report benzodiazepine use (odds ratio O.R. 1.32, 95% C.I. 1.02-1.71, P c 0.05).
Benzodiazepine users were also significantly more likely than other IDU to be currently unemployed (O.R. 1.80, 95% C.I. 1.41-2.30, P < O.OOl), more likely to have not completed high school (O.R. 1.38, 95% C.I. 1.09-1.75, P c 0.01) and more likely to have been imprisoned (O.R. 1.34, 95% C.I. 1.05-1.70, P < 0.05). Drug use comparisons
The mean age of first injecting drug use reported by benzodiazepine users was significantly younger than that of the rest of the sample (18.0 years vs. 18.4; t = 2.96, d.f. = 1241, P < 0.005), as was the age of first regular injecting drug use (19.3 vs. 20.0, t = 2.46, d.f. = 1199, P c 0.01) (Table I). Benzodiazepine users reported significantly more injections during the last typical month of use (60.3 vs. 51.8, t = 2.21, d.f. = 1227, P c 0.05). Benzodiazepine users also reported having used significantly more drug classes in their life than other IDU (12.2 vs. 11.5, t = 3.03,
34
Table I. Injecting other IDLJ.
behaviour
Lifetime Age 1st injection Age regular injecting No. drug classes No. drug classes (injected) Typical month Heroin injections Amphetamines injections Cocaine injections Frequency shared Number shared with Intoxicated when used Never cleaned equipment Always cleaned equipment
of benzodiazepine
users
Benzodiazepine users
Other
18.0
19.3 12.2 4.8
18.4 20.0 11.5 4.7
46.3 13.4
29.4 7.5
6.7 21.3% 2.6 49.0% 6.5%
6.0 17.4% 1.3 43.2% 5.4%
83.6%
87.5%
and
IDU
df. = 1243, P < 0.005), although there was no significant difference in the mean number of drug classes which had been injected (4.8 vs. 4.7). Benzodiazepine users reported significantly more injections of heroin (46.3 vs. 29.4, t = 5.12, d.f. = 1243, P < 0.001) and amphetamines (13.4 vs. 7.5, t = 3.6, d.f. = 1242, P < 0.001) during the last typical month of use. There was no significant difference in the mean number of cocaine injections between the with both groups reporting a low groups, frequency of injection (6.7 vs. 6.0). HIV Risk-taking comparisons Benzodiazepine users reported a significantly greater frequency of injecting with borrowed equipment (21.3% of the time vs. 17.4%, t = 2.51, d.f. = 1165, P < 0.01) and had shared injecting equipment with significantly more people than other IDU in the 6 months preceding interview (2.6 vs. 1.3, t = 3.12, d.f. = 1295, P < 0.005). Benzodiazepine users were not significantly more likely than other IDU to have
ever shared equipment with a person they knew was HIV positive, although this comparison narrowly missed out on achieving significance (O.R. 1.97, 95% C.I. 0.97-3,97, P < 0.06). Benzodiazepine users reported a significantly higher proportion of injections as occurring while being ‘stoned, high, or drunk’ than other IDU (49.0% vs. 43.2%, t = 2.99, d.f. = 1224, P < 0.005). The proportions of benzodiazepine users and other IDU who never cleaned their injecting equipment (6.5% vs. 5.4%) and those who always cleaned (83.6 vs. 87.5) were not significantly different. The sample as a whole was sexually active, with 94.5% of subjects having had sex in the year preceding interview (Table II). The majority of subjects (72.9%) reported more than one partner during this time. The median number of partners for the sample was three. Benzodiazepine users were no more likely than other IDU to report multiple partners. Benzodiazepine users were, however, 1.76 times more likely
Table II. Sexual other IDU.
behaviour
of benzodiazepine
Benzodiazepine users Number of partners 0 1 >1 Median
25
(5.5%)
93 (20.4%) 570 (74.1%) 4
Condom use (all partners) Vaginal sex: Never 149 (38.4Yu) Always 48 (12.4%) Anal sex: Never 41 (46.1%) Always 15 (16.9%) (Regular partners) Vaginal sex: Never Always Anal sex: Never Always
users
Other
and
IDU
43 (5.5%) 176 (22.3%) 570 (72.2%) 3
242 (36.6%) 65 (9.8%) 15 (16.9%) 28 (20.0’10)
157 (47.9%) 26 (7.9%)
293 (49.4%) 41 (6.9%)
36 (55.3%) 7 (10.8%)
66 (51.6%) 19 (14.9%)
35
than other IDU to report having engaged in prostitution (95% C.I. 1.24-2.48, P < 0.001). Condom use was extremely low among both groups (Table II). There were no significant differences in the frequency of condom use between groups for either vaginal or anal sex. There was a small but significant difference between the groups in the number of sexually transmissible diseases ever reported, with benzodiazepine users reporting more diseases (0.7 vs. 0.5, t = 2.38, d.f. = 1235, P < 0.05). Despite their generally higher levels of risktaking behaviour, seronegative benzodiazepine likely than other were no more users seronegative IDU to state that they had a reasonably good chance of contracting HIV (defined as 10% or greater): 25.4% of benzodiazepine users vs. 22.0% of other IDU. Large proportions of both groups thought that they had either no chance of a one in a million chance of contracting HIV (27.5% of benzodiazepine users vs. 28.5% of other IDU). The groups were not significantly different in this perception. Discussion
Benzodiazepine use was widespread amongst subjects in this sample of IDU. Overall, 36.6% of IDU in this study reported using benzodiazepines during their last typical month of injecting drug use, with a fifth of subjects reporting daily use. Given the associations between benzodiazepine use and injecting drug use found in this study, the high prevalence of benzodiazepine use is cause for concern. Benzodiazepine users injected more frequently in a typical month, injected heroin more often and, surprisingly given contradictory pharmacological effects, injected amphetamines more frequently than other IDU. They had also had significantly more poly-drug use than other IDU. This pattern of use may suggest that benzodiazepine users are seeking intoxication as such, rather than the effects of a particular drug. In addition to injecting more frequently than other IDU, benzodiazepine users also engaged in significantly more HIV risk-taking. In relation to injecting behaviour, benzodiazepine users
shared injecting equipment more frequently and shared with more people than did other IDU. These findings from an Australian sample are consistent with those of studies conducted in the United States (Metzger et al. 1991) and Britain (Klee et al. 1990b). One possible factor which may be related to these behaviours is the finding that benzodiazepine users reported being ‘stoned, high or drunk’ more often when they were injecting than did other IDU. This may contribute to either disinhibition or short-term memory loss, increasing the probability of risky behaviour . In contrast to injecting behaviour, benzodiazepine users did not differ from other IDU in number of sexual partners or condom use. For both groups multiple partners were the norm and condom use was extremely low. The latter finding is consistent with other studies (e.g., Klee et al. 1990a; Sasse et al., 1989). Benzodiazepine users were, however, 1.76 times more likely than other IDU to have engaged in prostitution. This may be a reflection of the cost of their more frequent drug use, thus increasing the likelihood of prostitution to support continued drug use. Despite the fact that benzodiazepine users were engaging in more risk-taking behaviour than other IDU, they did not see themselves at more risk for contracting HIV than other IDU. In fact, over a quarter of benzodiazepine users rated their risk at zero or one in a million. Clearly, the risk perception of this group does not accord with their actual behaviour. If behaviour change is to be achieved amongst this group, attention must be paid to altering their risk perception. Overall, the demographic and drug use profiles benzodiazepine users would appear to indicate that they are a more dysfunctional sub-group of IDU. They commenced injecting earlier than other IDU, were more likely to be unemployed, are less educated and more likely to have been imprisoned, inject more frequently, have more poly-drug use, share needles more frequently and with more people. Clearly interventions aimed at reducing risk-taking among IDU need to pay particular attention to this sub-group.
36
In summary, this study found a high prevalence of benzodiazepine use among IDU and that the use of benzodiazepines was associated with more HIV risk-taking. The demographic and drug use profiles of this group indicate them to be a more dysfunctional group of IDU. In terms of HIV risk-taking and the consequent spread of HIV, benzodiazepine users are a group which require particular attention. Acknowledgments
This research was funded by a Commonwealth AIDS Research Grant and the National Campaign Against Drug Abuse. References Batki, S.L., Sorenson, J.L., Gibson, D.R. and Maude-Griffin, P. (1989) HIV infected IV drug users in methadone treatment: outcome and psychological correlates. In: A Preliminary Report: Problems of Drug Dependence (Harris, L.S., ed.), NIDA Research Monogr. 95. Chaisson, R.E., Bacchetti, P., Osmond, D., Brodie, B., Sande, M.A. and Moss, A.R. (1989) Cocaine use and HIV infection in intravenous drug users in San Francisco. J. Am. Med. Assoc. 261, 561- 565. Darke, S., Baker, A., Dixon, J., Wodak, A. and Heather, N. (1992) Drug use and HIV risk-taking behaviour among clients in methadone maintenance treatment. Drug Alcohol Depend. 29, 263-268. Darke, S., Hall, W. and Carless, J. (1990) Drug use, injecting practices and sexual behaviour of opioid users in Sydney, Australia. Br. J. Addict. 85, 1603 - 1609. Des Jarlais, D.C., Friedman, S.R. and Casriel, C. (1990) Target groups for preventing AIDS among intravenous drug users: 2. The hard data studies. J. Consult. Clin. Psychol. 58, 50-56. Des Jar&s, D.C., Wish, E., Friedman, S.R., Stoneburner, R.L., Yankovitz, F., Mildban, D., El-Sadr, W., Brady, E. and Cuadrado, M. (1987) Intravenous drug users and the sexual transmission of the acquired immunodeficiency syndrome. N.Y. State J. Med. 87, 283-286. Donoghoe, MC., Stimson, G. and Dolan, H.A. (1989) Sexual behaviour of injecting drug users and associated risks of HIV infection for non-injecting sexual partners. AIDS Care 1, 51-58.
Feucht, T.E., Stephens, R.C and Roman, S.W. (1990) The sexual behaviour of intravenous drug users: assessing the risk of the sexual transmission of HIV. J. Drug Issues 20, 195-213. Klee, H., Faugier, J., Hayes, C., Boulton, T. and Morris, J. (1990a) Sexual partners of injecting drug users: the risk of HIV infection. Br. J. Addict. 85, 413-418. Klee, H., Faugier, J., Hayes, C., Boultcn, T. and Morris, J. (1990b) AIDS-related risk behaviour, polydrug use and temazepam. Br. J. Addict. 85, 1125-1132. Lishner, D.M. and Look, M.S. (1990) Needle sharing practices and risk for AIDS transmission among intravenous drug users in Seattle. Int. J. Addict. 25, 1475 - 1483. Metzger, D., Woody, G., DePhilipis, D., McLellan, A.T., O’Brien, C.P. and Platt, J.J. (1991) Risk factors for needle sharing among methadone treated patients. Am. J. Psychiatr. 48, 636 - 640. Morlet, A., Darke, S., Guinan, J.J., Wolk, J. and Gold, J. (1990) Intravenous drug users who present to the Albion St. (AIDS) Centre for diagnosis and management of human immunodeficiency virus infection. Med. J. Australia 152, 78 - 80. National Centre in HIV Epidemiology and Clinical Research (1991) Cumulative analysis of AIDS cases in Australia. Philpot, C.R., Harcourt, C.L. and Edwards, J.M. (1989) Drug use by prostitutes in Sydney. Br. J. Addict. 84, 499 - 505. Rahman, M.Z., Ditton, J. and Forsyth, J.M. (1989) Variations in needle sharing practices among intravenous drug users in Possil (Glasgow). Br. J. Addict. 84, 923-927. Ross, M.W., Gold, J., Wodak, A.D. and Miller, M.E. (1991) Sexually transmissible diseases in injecting drug users. Genitourinary Med. 67, 32 - 36. Ross, M.W., Wodak, A.D., Gold, J. and Miller, M.E. Sexual behaviour in injecting drug users. J. Psychol. Human Sexuality (in press). Sasse, H., Salmaso, S., Contis, S. and the First Drug User Multicentre Study Group (1989) Risk behaviours for HIV-I in Italian drug users: report from a multicentre study. J. AIDS 2, 486-496. Saxon, A.J., Calsyn, D.A., Whittaker, S. and Freeman, G. (1991) Sexual behaviours of intravenous drug users in treatment. J. AIDS 4, 938-944. Torrens, M., San, L., Peri, J.M. and Olle, J.M. (1991) Cocaine abuse among heroin addicts in Spain. Drug Alcohol Depend. 27, 29-34. World Health Organization and the Centers for Disease Control (1991) Statistics from the World Health Organization and the Centers for Disease Control. J. AIDS, 5, 1399-1403.
