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Alcohol usage and associated treatment outcomes for opiate users entering treatment in Ireland
Drug and Alcohol Dependence 107 (2010) 56–61
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Drug and Alcohol Dependence journal homepage: www.elsevier.com/locate/drugalcdep
Alcohol usage and associated treatment outcomes for opiate users entering treatment in Ireland R.D. Stapleton, C.M. Comiskey ∗ School of Nursing and Midwifery, Trinity College Dublin, 24 D’Olier St., Dublin 2, Ireland
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Article history: Received 31 October 2008 Received in revised form 11 September 2009 Accepted 11 September 2009 Available online 12 October 2009 Keywords: Alcohol use Opiates Treatment Cocaine Outcome
a b s t r a c t Evidence has shown that frequency and quantity of drug usage are reduced after treatment but the effect of opioid addiction treatment on alcohol consumption remains unclear. As part of the national Research Outcome Study in Ireland Evaluating drug treatment effectiveness (ROSIE, see www.nuim.ie/rosie) comprehensive drug and alcohol data on 404 opiate users were collected. This study recruited and followed up at 1 and 3 years a prospective cohort of 404 users entering a new treatment episode. Descriptive and inferential statistics were computed and logistic modelling was used to identify key factors effecting outcomes. The cohort represented 8.2% of all new treatments. Follow-up interview rate at 3 years was 88%. Analysis revealed that those who abstained from alcohol use at 3 years were less likely to be using heroin at 3 years than non-abstainers. In addition, those who abstained from alcohol use at 3 years were also less likely to be using methadone, benzodiazepines and cocaine at 3 years than alcohol users. Outcomes for medium and heavy drinkers were found not to be as good as alcohol abstainers. Finally males tended to reduce the frequency and level of alcohol usage after entering treatment more than females. Results demonstrate to clinicians that an alcohol strategy is a key component of opiate treatment planning and a comprehensive and regular assessment of the client’s alcohol and drug use profile is essential if treatment interventions are to have maximum impact on outcomes. © 2009 Elsevier Ireland Ltd. All rights reserved.
1. Introduction Ongoing alcohol misuse by clients in opiate drug treatment remains a compelling issue for clinicians and treatment providers. Within the drug misusing population, the misuse of alcohol is an important problem due to the increased health risks associated with alcohol misuse (Gossop et al., 2003). For example, the high rates of hepatitis B and C infection among opiate users is known to elevate the health risks of excessive drinking (Baffis et al., 1999). Further, when alcohol is taken consistently in large amounts over an extended period or taken to excess in any one period, this can lead to problems for the individual and for the wider community (National Alcohol Policy: Ireland, 1996) and when used with other sedative drugs alcohol consumption increases the risk of overdose (Gossop et al., 1996). Heavy drinking was found to be common among opiate users entering treatment in the United Kingdom (Gossop et al., 2000) and the United States (Lehman and Simpson, 1990; Lehman et al., 1990). In the Drug Abuse Treatment Outcome Study (DATOS), approximately 40% of the cohort was alcohol dependent at intake indicating the size of the problem in the US.
∗ Corresponding author. Tel.: +353 1 8962776; fax: +353 1 8963001. E-mail address: [email protected] (C.M. Comiskey). 0376-8716/$ – see front matter © 2009 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.drugalcdep.2009.09.007
Numerous articles have also investigated the effects of alcohol on various treatment outcomes for patients in methadone maintenance treatment programs. It was observed that that entrance into treatment did not lead to either increased or decreased alcohol misuse while those who did misuse alcohol whilst in treatment tended to have a history of alcohol misuse (Rounsaville et al., 1982). Other authors assessed the usage of cocaine, amphetamines, illegal methadone, tranquilizers, marijuana, and alcohol at follow-up and found a decline in the use of all substances except alcohol (Fairbank et al., 1993). Others reported that in general alcohol consumption at admission and throughout follow-up was not associated with more frequent use of opioids (Simpson and Sells, 1990). A comparison of active alcoholics and other patients in a methadone maintenance program found no significant differences with the exception of alcohol related hospitalizations (Stimmel et al., 1982), while others (Jackson et al., 1982) found that consumption of alcohol among a cohort of active alcoholic narcotic users which were in a methadone program decreased with time. The relationship between alcohol usage in veteran narcotic addicts in methadone maintenance programs was investigated and the authors found no changes in alcohol use (Marcovici et al., 1980). However, problem drinkers tended to be involved in more criminal activity, they showed more evidence of depression and anxiety, and were more likely to continue to use illicit drugs.
R.D. Stapleton, C.M. Comiskey / Drug and Alcohol Dependence 107 (2010) 56–61
The scale of the opiate use problem in Ireland is considerable and in a study of five European cities, Dublin was found to have one of the highest opiate using prevalence rates (Comiskey and Barry, 2001). Furthermore, the need for a coordinated drug and alcohol policy based on the current levels of prevalence and incidence of use in Ireland have been highlighted (Butler, 2002). The research presented here aimed to provide a prospective investigation into changes in the frequency of alcohol usage and quantity of usage at drug treatment intake and post-intake for an Irish population of opiate users. We investigated levels of alcohol usage, drug usage, criminal activity, medical service usage and change in drinking habits. The objective was to contribute to the evidence on the effects of alcohol usage among opioid users entering treatment. In this way, we sought to aid policy makers, clinicians and methadone maintenance treatment program providers by establishing whether the success rate of a program may be, in part, related to the alcohol using habits of the client. The data used in this paper were collected as part of the Research Outcome Study in Ireland Evaluating drug treatment effectiveness (ROSIE, see www.nuim.ie/rosie). The ROSIE study was the first national, prospective, longitudinal opiate drug treatment outcome study in Ireland.
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of approximately 17% of all new methadone treatments. Further, 682 of the 4900 cases commenced a detoxification programme. Eighty-one ROSIE participants were recruited from this modality, giving a national coverage of approximately 12%. 2.2. Statistical analysis The collected data were analysed through the provision of descriptive statistical analyses and comparisons among the three time points. Associations between quantity, frequency and classification of alcohol usage (abstain, medium, and heavy) with crime, employment, and medical service usage for intake, one year post-intake and three years post-intake were investigated. Factors associated with a change in status of alcohol usage between any two of the time points under consideration and changes in drug usage were investigated controlling for gender, age and drug usage at intake. Continuous variables were analysed using means, standard deviation and Student’s t-test for two different samples or for paired samples. Statistical analysis of categorical variables was conducted using frequencies and chi-square tests. Where applicable, analyses were conducted using logistic regression, controlling for the effects of the covariates age, gender and usage at treatment intake. All two-way interactions were considered initially in the model with backwards selection used to determine significant terms with a p-value of <0.05 termed significant. All statistical analysis was conducted using SPSS (version 14.0) for windows.
3. Results 3.1. The cohort recruited and follow-up rates
2. Methods 2.1. Subjects For the ten-month period between September 2003 and July 2004, 404 new opiate drug-treatment clients completed baseline interviews for the ROSIE study. Only clients who were presenting for a new treatment episode were recruited, where new treatment episode was defined to be those who were never treated before and this was their first treatment, or, clients who had received treatment before but had not received their current treatment modality before, or, clients who had not received any form of treatment in the past six months. The distribution of treatment settings and modalities achieved in the ROSIE study reflected the known distribution at the time of recruitment. Similarly the gender ratios were planned to reflect the distribution of treated cases recorded in the national treatment register systems. Recruitment occurred in both inpatient (hospitals, residential programmes and prisons) and outpatient settings (community and health board clinics, and general practitioners), across four modalities; methadone (53%, n = 215), supervised detoxification programmes (20%, n = 81), abstinencebased programmes (20%, n = 82) and needle exchanges (7%, n = 26). The treatment agencies where clients were recruited from were sampled in a non-random basis to reflect the known geographical spread of provision and range of services. Finally the Maudsley Addiction Profile (MAP) instrument, which has been tested for validity and reliability, was used as the basic tool to measure the treatment outcomes (Marsden et al., 1998). At a national level, a database on all drug treatment episodes in a calendar year are maintained by the National Drug Treatment Reporting System (NDTRS) of the Drug Misuse Research Division of the Health Research Board. Compliance with this reporting system requires that one form be completed for each person who received treatment for problematic drug use at each treatment centre. NDTRS reports that there were 4900 cases commencing/recommencing treatment for problem drug use (not specifically opiate use) in 2003, giving the ROSIE study a minimum national coverage rate of 8.2% of all new treatments. In addition, 1265 of these cases commenced/recommenced methadone treatment. As 215 of the ROSIE participants were recruited within the methadone modality, the study has a national coverage rate
The mean age of the ROSIE sample at intake was 27.4 years (SD = 5.7). The gender grouping was 72% male and 28% female, with no significant difference between age for males and females. Of the sample, 81% had used heroin in the last ninety days at intake, 47% had used illicit methadone, 45% had used benzodiazepines and 45% had used cocaine. Full details on all intake characteristics are available elsewhere (Cox and Comiskey, 2007). Follow-up rates at 1 and 3 years were exceptionally high by international standards with 76% (n = 305) successfully completing their interview at 1 year and 88% (n = 357) successfully completing their final interview at 3 years. An analysis was conducted at 1 year to ascertain if there were any fundamental differences between those followed-up and those lost to follow-up and no differences were found. For the purposes of this analysis, only those who were interviewed at intake, one year post-intake (1 year) and three years post-intake (3 years) and not in needle exchange were considered for the sample (n = 271; 71.7%). Of these 271 subjects, 29 had missing or incomplete data for at least one of the variables under investigation and were consequently omitted. Thus, the remaining sample consisted of n = 242 (64%) subjects. 3.2. Alcohol usage at intake, 1 year and 3 years For the initial analysis, the sample was subdivided into three categories; ‘abstainers’ defined as not drinking in the last ninety days for both males and females, ‘medium drinkers’ defined as drinking more than 0 g and less than 70 g for males and more than 0 g and
Table 1 Descriptive analysis of alcohol usage in last ninety days. Male (n = 186): mean (SD)
Number of days used Grams used on a typical alcohol using day Grams used on a typical day
Female (n = 71): mean (SD)
Intake
1 year
3 years
Intake
1 year
3 years
14.7 (24.0) 75.8 (105.7) 24.1 (51.0)
9.2 (20.8) 52.0 (134.1) 11.6 (32.8)
8.9 (20.1) 43.1 (72.3) 12.2 (38.5)
10.7 (22.8) 52.0 (77.1) 18.1 (59.9)
11.2 (21.5) 59.9 (112.4) 19.1 (59.8)
10.6 (20.4) 43.5 (93.1) 18.1 (70.5)
Male (n = 175): n (%)
Abstainers Medium drinkers Heavy drinkers
Female (n = 67): n (%)
Intake
1 year
3 years
Intake
1 year
3 years
76 (43.4) 14 (8.0) 85 (48.6)
104 (59.4) 25 (14.3) 46 (26.3)
103 (58.9) 26 (14.9) 46 (26.3)
29 (43.3) 9 (13.4) 29 (43.3)
29 (43.3) 14 (20.9) 24 (35.8)
35 (52.5) 12 (17.9) 20 (28.2)
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Table 2 Comparison of alcohol related variables between intake, 1 year and 3 years. Male
Average change in number of days used Change in grams used on typical using day Change in grams used on typical day
Female
Intake vs. 1 year
Intake vs. 3 years
1 year vs. 3 years
Intake vs. 1 year
Intake vs. 3 years
1 year vs. 3 years
5.5** 23.8* 12.5**
5.8** 32.7*** 11.9**
0.3 8.9 −0.5
−0.5 −7.9 −1.0
0.1 8.5 0.0
0.7 16.4 1.0
‘Change’ for time point ‘A’ vs. time point ‘B’ equates to value for time point ‘A’ minus value for time point ‘B’. * p < 0.05. ** p < 0.01. *** p < 0.001. Table 3a Associations between alcohol use and crime, health and social variables at intake and 3 years. Period
Variable tested
Significant
p-Value
Acquisitive crime Drink and/or drug driving in the last ninety days Assault committed Selling drugs Earning money from crime or illegal activities
Borderline Yes Borderline No No
p = 0.073 p = 0.033 p = 0.064 – –
Acquisitive crime Drink and/or drug driving in the last ninety days Assault committed Selling drugs Earning money from crime or illegal activities
Yes No No No No
p = 0.035 – – – –
Crime
Intake
3 years
Period
Variable tested (number of days in last 90 days)
Significant
p-Value
Spending overnight in hospital Treated in accident and emergency Seen a GP Had outpatient appointments or community treatment
No No No Yes
– – – p = 0.041
Spending overnight in hospital Treated in accident and emergency Seen a GP Had outpatient appointments or community treatment
No No No No
– – – –
Variable tested
Significant
p-Value
Currently employed Had recent paid legal employment (in last 90 days) Currently experiencing financial difficulties
No No Yes
– – p = 0.038
Currently employed Had recent paid legal employment (in last 90 days) Currently experiencing financial difficulties
No No No
– – –
Health
Intake
3 years
Period Employment and finance Intake
3 years
less than 50 g for females per typical using day, and ‘heavy drinkers’ defined as drinking more than 70 g per typical using day for males with female heavy drinkers defined as drinking more than 50 g per typical using day. The use of grams was to ensure clarity in the quantity of alcohol consumed, particularly as the definition of a unit of alcohol can differ by country. The threshold values of 70 g and 50 g for males and females, respectively, are based on binge drinking levels described by the Health Promotion Unit (Mongan et al., 2007). In their article, binge drinking is defined as drinking seven or more drinks for males and five or more for females in a short period of time. As a standard drink in Ireland consists of 10 g, our threshold values are thus defined. Table 1 presents descriptive analysis of alcohol usage in last ninety days by gender. It is also worth noting that, after making a suitable adjustment in order to make comparisons with NTORS (more than 80 g (50 g) per drinking day is heavy for males (females)), there was a higher proportion of heavy drinkers among the ROSIE cohort with 38% defined as heavy drinkers based on this UK definition compared to about a quarter of the NTORS cohort (Gossop et al., 2000).
A comparison of alcohol related variables between intake and 1 year, intake and 3 years and 1 year and 3 years for males and females was also conducted (Table 2). 3.3. Alcohol and associations with, crime, health employment and finance at intake and 3 years Table 3a presents the analysis of a number of criminal, health and social related variables that were investigated for association with alcohol usage at intake and at 3 years. There was some evidence of associations between alcohol and crime at intake with a higher proportion of clients committing acquisitive crime in the medium alcohol users (55%) than in the heavy users (43%) or the abstainers (31%). Abstainers were also the lowest proportion of offenders (16%) in comparison to medium (30%) and heavy users (31%) in terms of drink and/or drug driving in the last ninety days. Finally, a larger proportion of heavy drinkers (11%) committed assault than either medium users (5%) or abstainers (3%). This association with acquisitive crime was also evident at 3 years with a lower proportion of abstainers commit-
R.D. Stapleton, C.M. Comiskey / Drug and Alcohol Dependence 107 (2010) 56–61
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Table 3b Drug usage and alcohol status at 3 years post-intake. Abstain vs. drinks alcohol (status at 3 years)
Using heroin at 3 years Days heroin used in last ninety at intake
Alcohol status at 3 years
0–9 10–49 50–90
Methadone used in last ninety days
Abstain (n = 138)
Drinks alcohol (n = 104)
13 (27%) 9 (45%) 35 (52%)
11 (39%) 15 (65%) 26 (49%)
10 (7%)
19 (18%)
Benzodiazepines used in last ninety days Age
Under 25 25 or over
Cocaine used in last ninety days
8 (18%) 27 (29%)
14 (41%) 18 (26%)
16 (12%)
32 (31%)
Significant alcohol effect
p-Value
Yes
p = 0.049
Yes
p = 0.018
Yes
p = 0.004
Yes
p < 0.001
Table 4 Drug usage and change in alcohol status between intake, 1 year and 3 years. 1 year alcohol change status from intake
Using heroin in last 90 days at 1 year
Male Female
p-Value
Worse (n = 38)
Same (n = 126)
Improved (n = 78)
9 (39%) 8 (53%)
50 (55%) 6 (17%)
30 (49%) 9 (53%)
3 years alcohol change status from intake Worse (n = 35) Using heroin in last 90 days at 3 years Days heroin used in last 90 at intake
p = 0.005
p-Value
Same (n = 119)
Improved (n = 85)
5 (50%) 6 (75%) 5 (29%)
12 (29%) 9 (53%) 36 (60%)
7 (29%) 9 (50%) 20 (47%)
2 (9%) 1 (8%)
12 (13%) 3 (10%)
6 (10%) 5 (20%)
p = 0.046
7 (47%) 8 (31%)
9 (27%) 27 (29%)
7 (21%) 16 (28%)
p = 0.044
11 (31%)
26 (22%)
11 (13%)
p = 0.014
p = 0.012 0–9 10–49 50–90
Methadone used in last 90 days at 3 years
Male Female
Benzodiazepines used in last 90 days at 3 years
Age under 25 Age 25 or over
Cocaine used in last 90 days at 3 years
ted crimes (9%) in comparison to medium (18%) and heavy users (21%). 3.4. Alcohol and drug usage at 3 years given drug usage at intake To investigate links between drinking and drug usage, a logistic regression approach was taken where drug usage in the last ninety days at 3 years was considered the response. Each of heroin, methadone, benzodiazepines and cocaine usage was modelled controlling for age, gender and drug usage at intake. The initial models that were considered included a term for abstaining or not abstaining from alcohol in the last ninety days at 3 years and investigated all possible two-way interactions, eliminating non-significant interactions through a backward selection process. Table 3b summarises the results. At 3 years, there was evidence that alcohol status had an effect on heroin usage at 3 years, with a lower proportion of alcohol abstainers being observed at 3 years among infrequent heroin users at intake. There was also an alcohol effect observed for the other drugs used at 3 years. 3.5. Investigation of those whose drinking habits change between intake, 1 and 3 years Links between change in drinking status between two time points, say A and B, and drug usage was investigated next. The subjects were divided into three groups; ‘worse’ which consisted of any clients whose drink status declined between time A and time B,
‘same’ which consisted of any clients whose drink status remained the same at time B as at time A, and ‘improved’ which consisted of any clients whose drink status improved between time A and time B. The models considered investigated links between drug usage at 1 year and change in alcohol status between intake and 1 year and also considered drug usage at 3 years and change in alcohol status between intake and 3 years. Drugs considered were heroin, methadone, benzodiazepines and cocaine. A summary of these results is provided in Table 4. At 1 year, in terms of using heroin in the last ninety days, a gender by change in alcohol status interaction effect was evident, with a much lower proportion of females who remained in the same alcohol category at 1 year as at intake using heroin. At 3 years, there was evidence that while alcohol status has an effect on heroin usage at 3 years among those using less frequently at intake, an increase in baseline usage results in a dampening of the alcohol effect confirming what was evident from the analysis detailed in Table 3a. In terms of methadone usage at 3 years, there was a significant interaction between gender and change in alcohol status. For benzodiazepine usage at 3 years, there was a significant interaction between age and change in alcohol status between intake and 3 years, again confirming the effect of alcohol as detailed in Table 3a. This interaction was highlighting that for those under 25 and worsening in terms of alcohol status between intake and 3 years, a higher proportion of users of benzodiazepines was evident than for the other groupings. Also for cocaine usage, a higher proportion of those in the worsening category were using cocaine than those in the other categories.
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R.D. Stapleton, C.M. Comiskey / Drug and Alcohol Dependence 107 (2010) 56–61
4. Discussion In summary, from the research findings and analysis three points pertinent to service providers, clinicians and policy makers emerged. Firstly, it was observed that males tended to reduce the frequency and level of alcohol usage after entering treatment but little change was observed for females. Secondly, medium and heavy drinkers at intake were not doing as well as abstainers. Finally and perhaps most significantly, at 3 years less alcohol abstainers were observed among infrequent heroin users at intake but those who did abstain from alcohol at 3 years were less likely to be using heroin at 3 years than non-abstainers. In addition, for methadone, benzodiazepines and cocaine, alcohol abstainers at 3 years were also less likely to be using these drugs at 3 years than non-abstainers. The second conclusion above which states that medium and heavy drinkers were not doing as well as abstainers supports findings in the drug and alcohol treatment literature. However the results in terms of crime are interesting in that they indicate that heroin users who abstain from alcohol are committing less acquisitive crime and drink/drug driving than those who are not abstaining, while heavy drinkers are more likely to commit assault. The smaller proportion of heavy drinkers having outpatient appointments or community treatment at intake also support two separate studies of health maintenance organisations in the US both of which reported that heaviest drinkers had fewer outpatient visits than moderate drinkers and abstainers (Armstrong et al., 1998; Zarkin et al., 2004). A link between heavy drinking and drug misuse which suggested that those who remain heavy drinkers in the follow-up period or become heavy drinkers in the follow-up period were more likely to be using cocaine, amphetamines, and non-prescribed benzodiazepines has been reported (Gossop et al., 2003). However the authors did not find any association between heavy drinking and opiate use. Two post-treatment drinking patterns among drug have been proposed (Simpson and Lloyd, 1981). One pattern involved substitution of alcohol for opioids. This occurred among a minority (about 13%) of their sample. A more common pattern involved the misuse of multiple substances including alcohol and non-opioid drugs. This negative effect of alcohol on drug usage observed in other studies (Gossop et al., 2003; Simpson and Lloyd, 1981) was also evident in our study for non-prescribed methadone, benzodiazepines (among younger users) and cocaine. However, in addition the more comprehensive analysis presented here demonstrates a further effect of alcohol use at 3 years on heroin use at 3 years with higher proportions of alcohol use at 3 years being observed among those who used heroin less frequently at intake. This finding appears to support the findings observed in the minority case of other research (Simpson and Lloyd, 1981). While results presented support and expand the findings in these earlier studies all results must be interpreted in light of the limitations of the research. Clients were recruited from three separate treatment modalities with varying treatment philosophies and objectives. Furthermore, clients were distributed among a range of national treatment services and agencies and many of these services have different treatment facilities. Finally, while the overall follow-up rate was very high there was considerable missing data in the detailed client interviews. However in-spite of these limitations, the results clearly demonstrate, that the associations and links between alcohol and drug use are not straightforward and that the nature of the association can depend on the drug used at follow-up, the gender, the age group and in the case of heroin the level of use at baseline. Clearly in terms of treatment planning, service provision and policy it is not a simple case of ‘one size fits all’ and the inclusion of an alcohol strategy into
treatment is but a first step. A comprehensive and regular assessment of the client’s ongoing or changing drug and alcohol use profile is essential if treatment interventions are to be targeted effectively at improving client outcomes and the allocation of scarce resources. Role of funding source This research was funded by The National Advisory Committee for Drugs (NACD) of the Irish Government Department of Community, Rural and Gaeltacht Affairs. The NACD provided the support of a research advisory group consisting of volunteers who were professionals working in drug treatment services and policy in Ireland. The NACD had no role in the analysis and interpretation of this data; or in the writing of this paper but volunteers on the research advisory group did facilitate where appropriate access to treatment service facilites. Contributors Author Comiskey designed the study and wrote the protocol. Author Comiskey managed the literature searches and summaries of previous related work. Author Comiskey was responsible for all recruitment and follow-up data, data management and preliminary statistical analysis. Author Stapleton undertook the statistical analysis on alcohol use, and author Stapleton wrote the first draft of the manuscript. Author Comiskey revised the first draft. All authors contributed to and have approved the final manuscript. Conflict of interest Author Comiskey has consulted in the past prior to the preparation of this manuscript for the National Advisory Committee on Drugs. All authors declare that they have no conflicts of interest. Acknowledgement We thank the National Advisory Committee on Drugs who funded the ROSIE project (see www.nuim.ie/rosie) the project from which the data for this paper was obtained. References Armstrong, M.A., Midanik, L.T., Klatsky, A.L., 1998. Alcohol consumption and utilization of health services in a health maintenance organization. Med. Care 36, 1599–1605. Baffis, V., Shrier, I., Sherker, A.H., Szilagyi, A., 1999. Use of Interferon for prevention of hepatocellular carcinoma in cirrhotic patients with Hepatitis B or Hepatitis C infection. Ann. Intern. Med. 131, 696–701. Butler, S., 2002. Alcohol, Drugs and Health Promotion in Modern Ireland. Institute of Public Administration, Dublin, Ireland. Comiskey, C.M., Barry, J., 2001. The prevalence and health implications of opiate use in Dublin. Eur. J. Public Health 11 (2), 198–201. Cox, G., Comiskey, C.M., 2007. Characteristics of opiate users presenting for a new treatment episode: baseline data from the national drug treatment outcome study in Ireland (ROSIE). Drugs Ed. Prev. Policy 14 (3), 217–230. Fairbank, J.A., Dunteman, G.H., Condelli, W.S., 1993. Do methadone patients substitute other drugs for heroin? Predicting substance use at 1-year follow-up. Am. J. Drug Alcohol Abuse 19 (4), 465–474. Gossop, M., Griffiths, P., Powis, B., Williamson, S., Strang, J., 1996. Frequency of nonfatal overdose: survey of heroin users recruited in non-clinical settings. Br. Med. J., 313–402. Gossop, M., Marsden, J., Stewart, D., Rolfe, A., 2000. Patterns of drinking and drinking outcomes among drug misusers: one year follow-up results. J. Subst. Abuse Treat. 19, 45–50. Gossop, M., Browne, N., Stewart, D., Marsden, J., 2003. Alcohol use outcomes and heavy drinking at 4–5 years among a treatment sample of drug misusers. J. Subst. Abuse Treat. 25, 135–143. Jackson, G., Korts, D., Hanbury, R., Sturiano, V., Wolpert, L., Cohen, M., Stimmel, B., 1982. Alcohol consumption in persons in methadone maintenance therapy. Am. J. Drug Alcohol Abuse 9 (1), 69–76. Lehman, W.E., Simpson, D.D., 1990. Alcohol Use. In: Simpson, D.D., Bells, S.S. (Eds.), Opioid Addiction and Treatment: A 12-Year Follow-up. Krieger, Melbourne, FL.
R.D. Stapleton, C.M. Comiskey / Drug and Alcohol Dependence 107 (2010) 56–61 Lehman, W.E., Barrett, M.E., Simpson, D.D., 1990. Alcohol use by heroin addicts 12 years after drug abuse treatment. J. Stud. Alcohol 51, 233–244. Marcovici, M., McLellan, A.T., O’Bren, C.P., Rosenzweig, J., 1980. Risk for alcoholism and methadone treatment: a longitudinal study. J. Nerv. Ment. Dis. 168 (9), 556–558. Marsden, J., Gossop, M., Stewart, D., Best, D., Farrell, M., Lehmann, P., Edwards, C., Strang, J., 1998. The Maudsley Addiction Profile (MAP): a brief instrument for assessing treatment outcome. Addiction 93 (12), 1857– 1867. Mongan, D., Reynolds, S., Fanagan, S., Long, J., 2007. Health-related consequences of problem alcohol use. Overview 6. Health Research Board, Dublin. National Alcohol Policy: Ireland, 1996. Stationary Office, Dublin.
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Rounsaville, B.J., Weissman, M.M., Kleber, H.D., 1982. The significance of alcoholism in treated opiate addicts. J. Nerv. Ment. Dis. 170 (8), 479–488. Simpson, D.D., Lloyd, M.R., 1981. Alcohol use following treatment for drug addiction: a four year follow-up. J. Stud. Alcohol 42, 323–335. Simpson, D.D., Sells, S.B., 1990. Opioid Addiction and Treatment: A 12 Year Followup. Krieger Publishing Company, Malabar, FL. Stimmel, B., Hanbury, R., Sturiano, V., Korts, D., Jackson, G., Cohen, M., 1982. Alcoholism as a risk factor in methadone maintenance. A randomized controlled trial. Am. J. Med. 73 (5), 631–636. Zarkin, G.A., Bray, J.W., Babor, T.F., Higgins-Biddle, J.C., 2004. Alcohol drinking patterns and health care utilization in a managed care organization. Health Serv. Res. 39, 553–570.
Contents lists available at ScienceDirect
Drug and Alcohol Dependence journal homepage: www.elsevier.com/locate/drugalcdep
Alcohol usage and associated treatment outcomes for opiate users entering treatment in Ireland R.D. Stapleton, C.M. Comiskey ∗ School of Nursing and Midwifery, Trinity College Dublin, 24 D’Olier St., Dublin 2, Ireland
a r t i c l e
i n f o
Article history: Received 31 October 2008 Received in revised form 11 September 2009 Accepted 11 September 2009 Available online 12 October 2009 Keywords: Alcohol use Opiates Treatment Cocaine Outcome
a b s t r a c t Evidence has shown that frequency and quantity of drug usage are reduced after treatment but the effect of opioid addiction treatment on alcohol consumption remains unclear. As part of the national Research Outcome Study in Ireland Evaluating drug treatment effectiveness (ROSIE, see www.nuim.ie/rosie) comprehensive drug and alcohol data on 404 opiate users were collected. This study recruited and followed up at 1 and 3 years a prospective cohort of 404 users entering a new treatment episode. Descriptive and inferential statistics were computed and logistic modelling was used to identify key factors effecting outcomes. The cohort represented 8.2% of all new treatments. Follow-up interview rate at 3 years was 88%. Analysis revealed that those who abstained from alcohol use at 3 years were less likely to be using heroin at 3 years than non-abstainers. In addition, those who abstained from alcohol use at 3 years were also less likely to be using methadone, benzodiazepines and cocaine at 3 years than alcohol users. Outcomes for medium and heavy drinkers were found not to be as good as alcohol abstainers. Finally males tended to reduce the frequency and level of alcohol usage after entering treatment more than females. Results demonstrate to clinicians that an alcohol strategy is a key component of opiate treatment planning and a comprehensive and regular assessment of the client’s alcohol and drug use profile is essential if treatment interventions are to have maximum impact on outcomes. © 2009 Elsevier Ireland Ltd. All rights reserved.
1. Introduction Ongoing alcohol misuse by clients in opiate drug treatment remains a compelling issue for clinicians and treatment providers. Within the drug misusing population, the misuse of alcohol is an important problem due to the increased health risks associated with alcohol misuse (Gossop et al., 2003). For example, the high rates of hepatitis B and C infection among opiate users is known to elevate the health risks of excessive drinking (Baffis et al., 1999). Further, when alcohol is taken consistently in large amounts over an extended period or taken to excess in any one period, this can lead to problems for the individual and for the wider community (National Alcohol Policy: Ireland, 1996) and when used with other sedative drugs alcohol consumption increases the risk of overdose (Gossop et al., 1996). Heavy drinking was found to be common among opiate users entering treatment in the United Kingdom (Gossop et al., 2000) and the United States (Lehman and Simpson, 1990; Lehman et al., 1990). In the Drug Abuse Treatment Outcome Study (DATOS), approximately 40% of the cohort was alcohol dependent at intake indicating the size of the problem in the US.
∗ Corresponding author. Tel.: +353 1 8962776; fax: +353 1 8963001. E-mail address: [email protected] (C.M. Comiskey). 0376-8716/$ – see front matter © 2009 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.drugalcdep.2009.09.007
Numerous articles have also investigated the effects of alcohol on various treatment outcomes for patients in methadone maintenance treatment programs. It was observed that that entrance into treatment did not lead to either increased or decreased alcohol misuse while those who did misuse alcohol whilst in treatment tended to have a history of alcohol misuse (Rounsaville et al., 1982). Other authors assessed the usage of cocaine, amphetamines, illegal methadone, tranquilizers, marijuana, and alcohol at follow-up and found a decline in the use of all substances except alcohol (Fairbank et al., 1993). Others reported that in general alcohol consumption at admission and throughout follow-up was not associated with more frequent use of opioids (Simpson and Sells, 1990). A comparison of active alcoholics and other patients in a methadone maintenance program found no significant differences with the exception of alcohol related hospitalizations (Stimmel et al., 1982), while others (Jackson et al., 1982) found that consumption of alcohol among a cohort of active alcoholic narcotic users which were in a methadone program decreased with time. The relationship between alcohol usage in veteran narcotic addicts in methadone maintenance programs was investigated and the authors found no changes in alcohol use (Marcovici et al., 1980). However, problem drinkers tended to be involved in more criminal activity, they showed more evidence of depression and anxiety, and were more likely to continue to use illicit drugs.
R.D. Stapleton, C.M. Comiskey / Drug and Alcohol Dependence 107 (2010) 56–61
The scale of the opiate use problem in Ireland is considerable and in a study of five European cities, Dublin was found to have one of the highest opiate using prevalence rates (Comiskey and Barry, 2001). Furthermore, the need for a coordinated drug and alcohol policy based on the current levels of prevalence and incidence of use in Ireland have been highlighted (Butler, 2002). The research presented here aimed to provide a prospective investigation into changes in the frequency of alcohol usage and quantity of usage at drug treatment intake and post-intake for an Irish population of opiate users. We investigated levels of alcohol usage, drug usage, criminal activity, medical service usage and change in drinking habits. The objective was to contribute to the evidence on the effects of alcohol usage among opioid users entering treatment. In this way, we sought to aid policy makers, clinicians and methadone maintenance treatment program providers by establishing whether the success rate of a program may be, in part, related to the alcohol using habits of the client. The data used in this paper were collected as part of the Research Outcome Study in Ireland Evaluating drug treatment effectiveness (ROSIE, see www.nuim.ie/rosie). The ROSIE study was the first national, prospective, longitudinal opiate drug treatment outcome study in Ireland.
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of approximately 17% of all new methadone treatments. Further, 682 of the 4900 cases commenced a detoxification programme. Eighty-one ROSIE participants were recruited from this modality, giving a national coverage of approximately 12%. 2.2. Statistical analysis The collected data were analysed through the provision of descriptive statistical analyses and comparisons among the three time points. Associations between quantity, frequency and classification of alcohol usage (abstain, medium, and heavy) with crime, employment, and medical service usage for intake, one year post-intake and three years post-intake were investigated. Factors associated with a change in status of alcohol usage between any two of the time points under consideration and changes in drug usage were investigated controlling for gender, age and drug usage at intake. Continuous variables were analysed using means, standard deviation and Student’s t-test for two different samples or for paired samples. Statistical analysis of categorical variables was conducted using frequencies and chi-square tests. Where applicable, analyses were conducted using logistic regression, controlling for the effects of the covariates age, gender and usage at treatment intake. All two-way interactions were considered initially in the model with backwards selection used to determine significant terms with a p-value of <0.05 termed significant. All statistical analysis was conducted using SPSS (version 14.0) for windows.
3. Results 3.1. The cohort recruited and follow-up rates
2. Methods 2.1. Subjects For the ten-month period between September 2003 and July 2004, 404 new opiate drug-treatment clients completed baseline interviews for the ROSIE study. Only clients who were presenting for a new treatment episode were recruited, where new treatment episode was defined to be those who were never treated before and this was their first treatment, or, clients who had received treatment before but had not received their current treatment modality before, or, clients who had not received any form of treatment in the past six months. The distribution of treatment settings and modalities achieved in the ROSIE study reflected the known distribution at the time of recruitment. Similarly the gender ratios were planned to reflect the distribution of treated cases recorded in the national treatment register systems. Recruitment occurred in both inpatient (hospitals, residential programmes and prisons) and outpatient settings (community and health board clinics, and general practitioners), across four modalities; methadone (53%, n = 215), supervised detoxification programmes (20%, n = 81), abstinencebased programmes (20%, n = 82) and needle exchanges (7%, n = 26). The treatment agencies where clients were recruited from were sampled in a non-random basis to reflect the known geographical spread of provision and range of services. Finally the Maudsley Addiction Profile (MAP) instrument, which has been tested for validity and reliability, was used as the basic tool to measure the treatment outcomes (Marsden et al., 1998). At a national level, a database on all drug treatment episodes in a calendar year are maintained by the National Drug Treatment Reporting System (NDTRS) of the Drug Misuse Research Division of the Health Research Board. Compliance with this reporting system requires that one form be completed for each person who received treatment for problematic drug use at each treatment centre. NDTRS reports that there were 4900 cases commencing/recommencing treatment for problem drug use (not specifically opiate use) in 2003, giving the ROSIE study a minimum national coverage rate of 8.2% of all new treatments. In addition, 1265 of these cases commenced/recommenced methadone treatment. As 215 of the ROSIE participants were recruited within the methadone modality, the study has a national coverage rate
The mean age of the ROSIE sample at intake was 27.4 years (SD = 5.7). The gender grouping was 72% male and 28% female, with no significant difference between age for males and females. Of the sample, 81% had used heroin in the last ninety days at intake, 47% had used illicit methadone, 45% had used benzodiazepines and 45% had used cocaine. Full details on all intake characteristics are available elsewhere (Cox and Comiskey, 2007). Follow-up rates at 1 and 3 years were exceptionally high by international standards with 76% (n = 305) successfully completing their interview at 1 year and 88% (n = 357) successfully completing their final interview at 3 years. An analysis was conducted at 1 year to ascertain if there were any fundamental differences between those followed-up and those lost to follow-up and no differences were found. For the purposes of this analysis, only those who were interviewed at intake, one year post-intake (1 year) and three years post-intake (3 years) and not in needle exchange were considered for the sample (n = 271; 71.7%). Of these 271 subjects, 29 had missing or incomplete data for at least one of the variables under investigation and were consequently omitted. Thus, the remaining sample consisted of n = 242 (64%) subjects. 3.2. Alcohol usage at intake, 1 year and 3 years For the initial analysis, the sample was subdivided into three categories; ‘abstainers’ defined as not drinking in the last ninety days for both males and females, ‘medium drinkers’ defined as drinking more than 0 g and less than 70 g for males and more than 0 g and
Table 1 Descriptive analysis of alcohol usage in last ninety days. Male (n = 186): mean (SD)
Number of days used Grams used on a typical alcohol using day Grams used on a typical day
Female (n = 71): mean (SD)
Intake
1 year
3 years
Intake
1 year
3 years
14.7 (24.0) 75.8 (105.7) 24.1 (51.0)
9.2 (20.8) 52.0 (134.1) 11.6 (32.8)
8.9 (20.1) 43.1 (72.3) 12.2 (38.5)
10.7 (22.8) 52.0 (77.1) 18.1 (59.9)
11.2 (21.5) 59.9 (112.4) 19.1 (59.8)
10.6 (20.4) 43.5 (93.1) 18.1 (70.5)
Male (n = 175): n (%)
Abstainers Medium drinkers Heavy drinkers
Female (n = 67): n (%)
Intake
1 year
3 years
Intake
1 year
3 years
76 (43.4) 14 (8.0) 85 (48.6)
104 (59.4) 25 (14.3) 46 (26.3)
103 (58.9) 26 (14.9) 46 (26.3)
29 (43.3) 9 (13.4) 29 (43.3)
29 (43.3) 14 (20.9) 24 (35.8)
35 (52.5) 12 (17.9) 20 (28.2)
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Table 2 Comparison of alcohol related variables between intake, 1 year and 3 years. Male
Average change in number of days used Change in grams used on typical using day Change in grams used on typical day
Female
Intake vs. 1 year
Intake vs. 3 years
1 year vs. 3 years
Intake vs. 1 year
Intake vs. 3 years
1 year vs. 3 years
5.5** 23.8* 12.5**
5.8** 32.7*** 11.9**
0.3 8.9 −0.5
−0.5 −7.9 −1.0
0.1 8.5 0.0
0.7 16.4 1.0
‘Change’ for time point ‘A’ vs. time point ‘B’ equates to value for time point ‘A’ minus value for time point ‘B’. * p < 0.05. ** p < 0.01. *** p < 0.001. Table 3a Associations between alcohol use and crime, health and social variables at intake and 3 years. Period
Variable tested
Significant
p-Value
Acquisitive crime Drink and/or drug driving in the last ninety days Assault committed Selling drugs Earning money from crime or illegal activities
Borderline Yes Borderline No No
p = 0.073 p = 0.033 p = 0.064 – –
Acquisitive crime Drink and/or drug driving in the last ninety days Assault committed Selling drugs Earning money from crime or illegal activities
Yes No No No No
p = 0.035 – – – –
Crime
Intake
3 years
Period
Variable tested (number of days in last 90 days)
Significant
p-Value
Spending overnight in hospital Treated in accident and emergency Seen a GP Had outpatient appointments or community treatment
No No No Yes
– – – p = 0.041
Spending overnight in hospital Treated in accident and emergency Seen a GP Had outpatient appointments or community treatment
No No No No
– – – –
Variable tested
Significant
p-Value
Currently employed Had recent paid legal employment (in last 90 days) Currently experiencing financial difficulties
No No Yes
– – p = 0.038
Currently employed Had recent paid legal employment (in last 90 days) Currently experiencing financial difficulties
No No No
– – –
Health
Intake
3 years
Period Employment and finance Intake
3 years
less than 50 g for females per typical using day, and ‘heavy drinkers’ defined as drinking more than 70 g per typical using day for males with female heavy drinkers defined as drinking more than 50 g per typical using day. The use of grams was to ensure clarity in the quantity of alcohol consumed, particularly as the definition of a unit of alcohol can differ by country. The threshold values of 70 g and 50 g for males and females, respectively, are based on binge drinking levels described by the Health Promotion Unit (Mongan et al., 2007). In their article, binge drinking is defined as drinking seven or more drinks for males and five or more for females in a short period of time. As a standard drink in Ireland consists of 10 g, our threshold values are thus defined. Table 1 presents descriptive analysis of alcohol usage in last ninety days by gender. It is also worth noting that, after making a suitable adjustment in order to make comparisons with NTORS (more than 80 g (50 g) per drinking day is heavy for males (females)), there was a higher proportion of heavy drinkers among the ROSIE cohort with 38% defined as heavy drinkers based on this UK definition compared to about a quarter of the NTORS cohort (Gossop et al., 2000).
A comparison of alcohol related variables between intake and 1 year, intake and 3 years and 1 year and 3 years for males and females was also conducted (Table 2). 3.3. Alcohol and associations with, crime, health employment and finance at intake and 3 years Table 3a presents the analysis of a number of criminal, health and social related variables that were investigated for association with alcohol usage at intake and at 3 years. There was some evidence of associations between alcohol and crime at intake with a higher proportion of clients committing acquisitive crime in the medium alcohol users (55%) than in the heavy users (43%) or the abstainers (31%). Abstainers were also the lowest proportion of offenders (16%) in comparison to medium (30%) and heavy users (31%) in terms of drink and/or drug driving in the last ninety days. Finally, a larger proportion of heavy drinkers (11%) committed assault than either medium users (5%) or abstainers (3%). This association with acquisitive crime was also evident at 3 years with a lower proportion of abstainers commit-
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Table 3b Drug usage and alcohol status at 3 years post-intake. Abstain vs. drinks alcohol (status at 3 years)
Using heroin at 3 years Days heroin used in last ninety at intake
Alcohol status at 3 years
0–9 10–49 50–90
Methadone used in last ninety days
Abstain (n = 138)
Drinks alcohol (n = 104)
13 (27%) 9 (45%) 35 (52%)
11 (39%) 15 (65%) 26 (49%)
10 (7%)
19 (18%)
Benzodiazepines used in last ninety days Age
Under 25 25 or over
Cocaine used in last ninety days
8 (18%) 27 (29%)
14 (41%) 18 (26%)
16 (12%)
32 (31%)
Significant alcohol effect
p-Value
Yes
p = 0.049
Yes
p = 0.018
Yes
p = 0.004
Yes
p < 0.001
Table 4 Drug usage and change in alcohol status between intake, 1 year and 3 years. 1 year alcohol change status from intake
Using heroin in last 90 days at 1 year
Male Female
p-Value
Worse (n = 38)
Same (n = 126)
Improved (n = 78)
9 (39%) 8 (53%)
50 (55%) 6 (17%)
30 (49%) 9 (53%)
3 years alcohol change status from intake Worse (n = 35) Using heroin in last 90 days at 3 years Days heroin used in last 90 at intake
p = 0.005
p-Value
Same (n = 119)
Improved (n = 85)
5 (50%) 6 (75%) 5 (29%)
12 (29%) 9 (53%) 36 (60%)
7 (29%) 9 (50%) 20 (47%)
2 (9%) 1 (8%)
12 (13%) 3 (10%)
6 (10%) 5 (20%)
p = 0.046
7 (47%) 8 (31%)
9 (27%) 27 (29%)
7 (21%) 16 (28%)
p = 0.044
11 (31%)
26 (22%)
11 (13%)
p = 0.014
p = 0.012 0–9 10–49 50–90
Methadone used in last 90 days at 3 years
Male Female
Benzodiazepines used in last 90 days at 3 years
Age under 25 Age 25 or over
Cocaine used in last 90 days at 3 years
ted crimes (9%) in comparison to medium (18%) and heavy users (21%). 3.4. Alcohol and drug usage at 3 years given drug usage at intake To investigate links between drinking and drug usage, a logistic regression approach was taken where drug usage in the last ninety days at 3 years was considered the response. Each of heroin, methadone, benzodiazepines and cocaine usage was modelled controlling for age, gender and drug usage at intake. The initial models that were considered included a term for abstaining or not abstaining from alcohol in the last ninety days at 3 years and investigated all possible two-way interactions, eliminating non-significant interactions through a backward selection process. Table 3b summarises the results. At 3 years, there was evidence that alcohol status had an effect on heroin usage at 3 years, with a lower proportion of alcohol abstainers being observed at 3 years among infrequent heroin users at intake. There was also an alcohol effect observed for the other drugs used at 3 years. 3.5. Investigation of those whose drinking habits change between intake, 1 and 3 years Links between change in drinking status between two time points, say A and B, and drug usage was investigated next. The subjects were divided into three groups; ‘worse’ which consisted of any clients whose drink status declined between time A and time B,
‘same’ which consisted of any clients whose drink status remained the same at time B as at time A, and ‘improved’ which consisted of any clients whose drink status improved between time A and time B. The models considered investigated links between drug usage at 1 year and change in alcohol status between intake and 1 year and also considered drug usage at 3 years and change in alcohol status between intake and 3 years. Drugs considered were heroin, methadone, benzodiazepines and cocaine. A summary of these results is provided in Table 4. At 1 year, in terms of using heroin in the last ninety days, a gender by change in alcohol status interaction effect was evident, with a much lower proportion of females who remained in the same alcohol category at 1 year as at intake using heroin. At 3 years, there was evidence that while alcohol status has an effect on heroin usage at 3 years among those using less frequently at intake, an increase in baseline usage results in a dampening of the alcohol effect confirming what was evident from the analysis detailed in Table 3a. In terms of methadone usage at 3 years, there was a significant interaction between gender and change in alcohol status. For benzodiazepine usage at 3 years, there was a significant interaction between age and change in alcohol status between intake and 3 years, again confirming the effect of alcohol as detailed in Table 3a. This interaction was highlighting that for those under 25 and worsening in terms of alcohol status between intake and 3 years, a higher proportion of users of benzodiazepines was evident than for the other groupings. Also for cocaine usage, a higher proportion of those in the worsening category were using cocaine than those in the other categories.
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4. Discussion In summary, from the research findings and analysis three points pertinent to service providers, clinicians and policy makers emerged. Firstly, it was observed that males tended to reduce the frequency and level of alcohol usage after entering treatment but little change was observed for females. Secondly, medium and heavy drinkers at intake were not doing as well as abstainers. Finally and perhaps most significantly, at 3 years less alcohol abstainers were observed among infrequent heroin users at intake but those who did abstain from alcohol at 3 years were less likely to be using heroin at 3 years than non-abstainers. In addition, for methadone, benzodiazepines and cocaine, alcohol abstainers at 3 years were also less likely to be using these drugs at 3 years than non-abstainers. The second conclusion above which states that medium and heavy drinkers were not doing as well as abstainers supports findings in the drug and alcohol treatment literature. However the results in terms of crime are interesting in that they indicate that heroin users who abstain from alcohol are committing less acquisitive crime and drink/drug driving than those who are not abstaining, while heavy drinkers are more likely to commit assault. The smaller proportion of heavy drinkers having outpatient appointments or community treatment at intake also support two separate studies of health maintenance organisations in the US both of which reported that heaviest drinkers had fewer outpatient visits than moderate drinkers and abstainers (Armstrong et al., 1998; Zarkin et al., 2004). A link between heavy drinking and drug misuse which suggested that those who remain heavy drinkers in the follow-up period or become heavy drinkers in the follow-up period were more likely to be using cocaine, amphetamines, and non-prescribed benzodiazepines has been reported (Gossop et al., 2003). However the authors did not find any association between heavy drinking and opiate use. Two post-treatment drinking patterns among drug have been proposed (Simpson and Lloyd, 1981). One pattern involved substitution of alcohol for opioids. This occurred among a minority (about 13%) of their sample. A more common pattern involved the misuse of multiple substances including alcohol and non-opioid drugs. This negative effect of alcohol on drug usage observed in other studies (Gossop et al., 2003; Simpson and Lloyd, 1981) was also evident in our study for non-prescribed methadone, benzodiazepines (among younger users) and cocaine. However, in addition the more comprehensive analysis presented here demonstrates a further effect of alcohol use at 3 years on heroin use at 3 years with higher proportions of alcohol use at 3 years being observed among those who used heroin less frequently at intake. This finding appears to support the findings observed in the minority case of other research (Simpson and Lloyd, 1981). While results presented support and expand the findings in these earlier studies all results must be interpreted in light of the limitations of the research. Clients were recruited from three separate treatment modalities with varying treatment philosophies and objectives. Furthermore, clients were distributed among a range of national treatment services and agencies and many of these services have different treatment facilities. Finally, while the overall follow-up rate was very high there was considerable missing data in the detailed client interviews. However in-spite of these limitations, the results clearly demonstrate, that the associations and links between alcohol and drug use are not straightforward and that the nature of the association can depend on the drug used at follow-up, the gender, the age group and in the case of heroin the level of use at baseline. Clearly in terms of treatment planning, service provision and policy it is not a simple case of ‘one size fits all’ and the inclusion of an alcohol strategy into
treatment is but a first step. A comprehensive and regular assessment of the client’s ongoing or changing drug and alcohol use profile is essential if treatment interventions are to be targeted effectively at improving client outcomes and the allocation of scarce resources. Role of funding source This research was funded by The National Advisory Committee for Drugs (NACD) of the Irish Government Department of Community, Rural and Gaeltacht Affairs. The NACD provided the support of a research advisory group consisting of volunteers who were professionals working in drug treatment services and policy in Ireland. The NACD had no role in the analysis and interpretation of this data; or in the writing of this paper but volunteers on the research advisory group did facilitate where appropriate access to treatment service facilites. Contributors Author Comiskey designed the study and wrote the protocol. Author Comiskey managed the literature searches and summaries of previous related work. Author Comiskey was responsible for all recruitment and follow-up data, data management and preliminary statistical analysis. Author Stapleton undertook the statistical analysis on alcohol use, and author Stapleton wrote the first draft of the manuscript. Author Comiskey revised the first draft. All authors contributed to and have approved the final manuscript. Conflict of interest Author Comiskey has consulted in the past prior to the preparation of this manuscript for the National Advisory Committee on Drugs. All authors declare that they have no conflicts of interest. Acknowledgement We thank the National Advisory Committee on Drugs who funded the ROSIE project (see www.nuim.ie/rosie) the project from which the data for this paper was obtained. References Armstrong, M.A., Midanik, L.T., Klatsky, A.L., 1998. Alcohol consumption and utilization of health services in a health maintenance organization. Med. Care 36, 1599–1605. Baffis, V., Shrier, I., Sherker, A.H., Szilagyi, A., 1999. Use of Interferon for prevention of hepatocellular carcinoma in cirrhotic patients with Hepatitis B or Hepatitis C infection. Ann. Intern. Med. 131, 696–701. Butler, S., 2002. Alcohol, Drugs and Health Promotion in Modern Ireland. Institute of Public Administration, Dublin, Ireland. Comiskey, C.M., Barry, J., 2001. The prevalence and health implications of opiate use in Dublin. Eur. J. Public Health 11 (2), 198–201. Cox, G., Comiskey, C.M., 2007. Characteristics of opiate users presenting for a new treatment episode: baseline data from the national drug treatment outcome study in Ireland (ROSIE). Drugs Ed. Prev. Policy 14 (3), 217–230. Fairbank, J.A., Dunteman, G.H., Condelli, W.S., 1993. Do methadone patients substitute other drugs for heroin? Predicting substance use at 1-year follow-up. Am. J. Drug Alcohol Abuse 19 (4), 465–474. Gossop, M., Griffiths, P., Powis, B., Williamson, S., Strang, J., 1996. Frequency of nonfatal overdose: survey of heroin users recruited in non-clinical settings. Br. Med. J., 313–402. Gossop, M., Marsden, J., Stewart, D., Rolfe, A., 2000. Patterns of drinking and drinking outcomes among drug misusers: one year follow-up results. J. Subst. Abuse Treat. 19, 45–50. Gossop, M., Browne, N., Stewart, D., Marsden, J., 2003. Alcohol use outcomes and heavy drinking at 4–5 years among a treatment sample of drug misusers. J. Subst. Abuse Treat. 25, 135–143. Jackson, G., Korts, D., Hanbury, R., Sturiano, V., Wolpert, L., Cohen, M., Stimmel, B., 1982. Alcohol consumption in persons in methadone maintenance therapy. Am. J. Drug Alcohol Abuse 9 (1), 69–76. Lehman, W.E., Simpson, D.D., 1990. Alcohol Use. In: Simpson, D.D., Bells, S.S. (Eds.), Opioid Addiction and Treatment: A 12-Year Follow-up. Krieger, Melbourne, FL.
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