Limited research suggests a strong association between adult Attention Deficit Hyperactivity Disorder (ADHD) and substance use disorders (SUD), with adult ADHD over-represented among people with substance use problems (20-40% prevalence). ADHD complicates the course of SUD, such that substance dependence is likely to have an earlier onset and greater severity among those with ADHD, and be more difficult to treat, with higher rates of relapse. The harms associated with alcohol and other drug use may be increased when ADHD is present, due to the inattention, carelessness, and impulsive risk-taking that are associated with ADHD. The increased risk of alcohol and other drug-related harm is of particular concern among younger people with ADHD, who already engage in more high risk behaviour than their non-ADHD and older counterparts. Risk behaviours that are likely to compound the harms already inherent in drug and alcohol use per se include engaging in high frequency substance use, harmful routes of drug administration, blood-borne virus risk behaviours, and high-risk driving behaviours. This study is part of an international multi-site study, known as the International ADHD in Substance use disorders Prevalence (IASP) study, coordinated by the International Collaboration on ADHD and Substance Abuse (ICASA). The IASP study is currently being conducted in Australia, Belgium, Finland, France, Hungary, Norway, Spain, Sweden, Switzerland, The Netherlands and the US.
The aims of this project are to:
- Assess current ADHD symptomatology among adults entering treatment for drug or alcohol dependence;
- Test the performance of internationally used screening instruments for adult ADHD among this specific clinical population;
- Investigate the relationship between ADHD symptoms and the onset and course of SUD, by comparing psychiatric comorbidity, onset of SUD, and health and social functioning of patients with and without symptoms of ADHD;
- Assess the nature and level of risk-taking behaviour associated with ADHD symptomatology
This study employed a cross-sectional survey design. A structured interview designed to screen for adult ADHD and examine SUD, psychiatric history, and drug-related, sexual and driving risk behaviours was administered to 488 adult alcohol and/or illicit drug users entering a new episode of treatment for drug and/or alcohol dependence.
Recruitment of study participants, coordinated by Ms Joanne Cassar (NDARC), Dr Susan Carruthers (NDRI) and Mr Jesse Young (NDRI), continued until August 31, 2011, at which time 303 interviews in Sydney and 185 interviews in Perth had been conducted. Recruitment in other participating countries ceased on August 31, 2011. A total sample of 3558 cases, from 47 inpatient and outpatient treatment sites, was obtained. Data analysis is complete.
Four papers based on the international findings have been published
van Emmerik-van Oortmerssen, K. et al (2013). Psychiatric comorbidity in treatment-seeking substance use disorder patients with and without attention deficit hyperactivity disorder: results of the IASP study. Addiction, 109(2): 262-272. doi: 10.1111/add.12370, http://onlinelibrary.wiley.com/doi/10.1111/add.12370/abstract
van de Glind, G., et al (2013). The International ADHD in Substance Use Disorders Prevalence (IASP) study: background, methods and study population. International Journal of Methods in Psychiatric Research, 22: 232–244. doi: 10.1002/mpr.1397, http://onlinelibrary.wiley.com/doi/10.1002/mpr.1397/abstract
van de Glind, G. et al (2013). Validity of the Adult ADHD Self-Report Scale (ASRS) as a screener for adult ADHD in treatment seeking substance use disorder patients, Drug and Alcohol Dependence, 132 (3): 587-596, http://dx.doi.org/10.1016/j.drugalcdep.2013.04.010
van de Glind, G. et al (2013). Variability in the prevalence of adult ADHD in treatment seeking substance use disorder patients: Results from an international multi-center study exploring DSM-IV and DSM-5 criteria, Drug and Alcohol Dependence, 134: 158-166. http://dx.doi.org/10.1016/j.drugalcdep.2013.09.026
Papers based on the Australian findings are in preparation.
This was the first Australian study to contribute to internationally comparable estimates of adult ADHD among people with SUD and the largest study of adult ADHD among substance-dependent populations in Australia to date. It was also the first Australian study to examine risk behaviours associated with ADHD among SUD populations. Improved identification of adult ADHD among people with SUD will assist in the tailoring of substance dependence treatment to the specific needs of those with ADHD and in the management of ADHD treatment, where indicated, leading to a better treatment outcome for the patient. This research also has important implications for children and adolescents with ADHD, who are at greater risk of developing problematic substance use and comorbid psychiatric disorders and engaging in harmful risk-taking behaviours. Alcohol and other drug use prevention and intervention strategies specifically targeted toward young people with ADHD will be of critical importance in reducing the harm and public health burden associated with SUD complicated by ADHD. Moreover, the findings will inform the development of future trials of ADHD treatment among substance-dependent populations. The proposed study will, therefore, guide the development of programmes to detect, diagnose and manage ADHD in people with SUD, contribute to improved and effective treatment of SUD in patients with comorbid ADHD, and inform strategies for prevention and monitoring of SUD in children and adolescents with ADHD.