Research project DR/55 (Research action DR)
BACKGROUND AND SITUATION OF THE STUDY
In Europe as well as in the United States, poly drug use has become the rule rather than the exception. In a society in which a diversity of psychoactive substances is available, it is easy for drug users to experiment with various combinations or to look for other substances that replace their primary drug of choice. Several researchers have demonstrated an increase in poly drug use over the past years. This evolution has also been observed among persons who ask for treatment in drug treatment services. Still, experts do not agree on how ‘poly drug use’ should be exactly defined. In the early seventies, this phenomenon was given a name for the first time. Later, several definitions have been used for this phenomenon. ‘Simultaneous’ as well as ‘consecutive’ use of substances can be considered as poly drug use. Therefore, it is important to verify how poly drug use has been conceptualized. Moreover, some authors suggest to differentiate within the group of poly drug users, e.g. based on the number of substances used or on the specific combination of substances that people use.
Poly drug use, and ‘simultaneous’ use in particular, may cause aggravated (physical and mental) health consequences. It is assumed that the prevalence of co-morbid psychiatric disorders is higher among poly drug users than among persons who just use one substance. Based on the literature, it further appears that poly drug use may affect treatment retention, c.q. the effectiveness of treatment. It makes treatment more difficult and professionals are challenged by a number of problems: poly drug users tend to drop-out early and more often and may show more behavioural problems (e.g., disinhibition, impulsivity and aggression) during treatment. The presence of co-occurring substance use problems – which are not recognised as such – may also be detrimental for the treatment outcome of the primary substance use disorder. Finally, adequate assessment and treatment of persons with so-called ‘dual dependence’ (alcohol and drugs) brings along new challenges for professionals.
Given the relative lack of information about the prevalence of poly drug use and the specific characteristics of poly drug users and given the unclear association between poly drug use and mental health, this study will focus on the prevalence of poly drug use and the profile of poly drug users as compared with problem drug users who use one single drug.
OBJECTIVES OF THE STUDY
The research objectives are threefold:
- First, we want to map the prevalence of poly drug use and the characteristics of poly drug users in outpatient and inpatient substance abuse treatment in Belgium;
- Second, we will explore the extent and type of psychiatric disorders among persons following substance abuse treatment in Belgium and the prevalence and type of DSM Axis I and II-disorders in this population;
- Third, we will compare the characteristics and psychiatric profile of poly drug users with that of persons who only use one substance.
RESEARCH METHODOLOGY
In order to realize these research objectives, the study consists of three parts: 1) literature review; 2) quantitative analysis of available databases; 3) presentation and discussion of the research findings and formulation of recommendations.
The study of the literature will start with an overview of the conceptualization of poly drug use in the international literature. The literature review on poly drug use will focus on the history and origins of this phenomenon: is poly drug use increasing, or is it rather the recognition of how it always was? Furthermore, we will look at the prevalence of poly drug use among alcohol and drug users and at factors and variables associated with it. The second part of the literature study will focus on ‘dual diagnosis’ and more specifically on the link between poly drug use (c.q. abuse or dependence) and psychopathology.
For the quantitative analyses, we will initially analyse data from all EuropASI-interviews administered in 2007-2008 in one of the treatment centres of De Sleutel (large network of drug treatment services in Flanders) and from the Sentinelle-network (network of specialized and non-specialized services that help drug users) in the region of Charleroi. Based on these analyses, we will study the prevalence of poly drug use and the characteristics of poly drug users. In addition, factors and variables asscoiated with poly drug use will be studied. The data from De Sleutel allow to estimate the prevalence and severity of pscyological problems among poly drug users. The Sentinelle-data will be analysed in order to assess changes in poly drug use between 1997 and 2007.
Although the data from De Sleutel and Sentinelle allow to analyse poly drug use and its correlates, information concerning psychological problems is rather weak. Therefore, we plan a secondary analysis of the data from two PhD-studies. Both studies have used the ASI to measure the severity of alcohol and drug related problems and used a valid instrument for assessing psychiatric disorders (i.e. the MINI and ADP-IV). Data from both studies will be merged into one database. Given the instruments used and the selection of a representative sample of alcohol and drug users treated in psychiatric hospitals, both studies offer the most reliable source to assess the association between poly drug use and psychopathology. However, since the majority of subjects in this sample are primary alcohol abusers and since an extensive network of specialized services for drug abusers is available in Belgium, we plan an extension of the two above-mentioned studies. Using the same assessment instruments, we intend to collect data among a sample of 180 persons entering drug treatment in Belgium. We will collect these data in 3 types of treatment services (methadone maintenance, detox and long-term residential treatment) in Flanders, Brussels and Walloonia. In each of these services, we aim to interview 30 persons, resulting in a total of 180 interviews.
In order to explore whether poly drug use is an increasing phenomenon or rather a constant observation, we will analyse EuropASI-data from three time-periods (1995-1997; 2000-2002; 2007-2009) for two therapeutic communities in Flanders regarding the number of poly drug users and the prevalence of psychological problems. Consequently, we will have an indication of any substantial shifts in poly drug use during the last 15 years in therapeutic communities. Finally, the Federal Service of Public Health will deliver a secondary analysis of the ‘Minimal Psychiatric Data’ (MPG), including (cross-sectional and longitudinal) data on the prevalence of substance dependence and psychopathology among patients admitted in psychiatric hospitals or at psychiatric wards of general hospitals in Belgium. For privacy reasons, the Federal Service of Public Health will only provide aggregated data regarding the research questions.
EXPECTED RESULTS AND PRODUCTS
The present research proposal aims at estimating the prevalence of poly drug use among drug abusers who ask for treatment. Moreover, we want to describe the specific characteristics of this population regarding their socio-economic status, financial situation, employment, social support, history of use and service utilisation, legal status, ... For this purpose, we will make use of data collected by De Sleutel, the Sentinelle–network and the MPG-data.
The second research question will be answered based on the EuropASI data collected by De Sleutel and on the data from Phd-studies of Kathy Colpaert (Deparment of Orthopedagogics, Ghent University) and Bieke De Wilde (CAPRI, University of Antwerp). These data will allow to estimate prevalence of ‘dual diagnosis’ among (poly) drug users who ask for treatment. Using valid and reliable assessment instruments for DSM IV-axis I and axis II–disorders, we will accurately assess the nature of these disorders. Moreover, the specific characteristics of these persons will be compared with those of substance abusers who don’t have psychological problems.
Finally, based on the EuropASI data and data from previous research, we will be able to estimate the prevalence of psychological problems among polydrug users and to assess whether there is a link between both constructs and which influence gender has on patterns of polydrug use. Given the combination of various quantitative databases, we will be able to answer the research questions in a differentiated way. Consequently, specific recommendations will be formulated to better meet the needs of poly drug users in treatment. Also, recommendations for further research will be suggested. Our findings and recommendations will be presented in a research report and in publications in (inter)national journals. Results will also be presented to potentially interested consumers through lectures and presentations at national and international conferences.
Poly substance use and mental health among individuals presenting for substance abuse treatment (Polymeh): final report
Vanderplasschen, Wouter - De Maeyer, Jessica - Colpaert, Kathy ... et al Brussels : Federal Science Policy, 2013 (SP2563)
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Poly substance use and mental health among individuals presenting for substance abuse treatment (Polymeh): Discussion and conclusions
Vanderplasschen, Wouter - De Maeyer, Jessica - Colpaert, Kathy ... et al Brussels : Federal Science Policy, 2013 (SP2564)
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