The clinical course of comorbid substance use disorder and attention deficit/hyperactivity disorder: protocol and clinical characteristics of the INCAS study

Abstract Background: Substance use disorders (SUD) often co-occur with attention deficit hyperactivity disorder (ADHD). Although the short-term effects of some specific interventions have been investigated in randomized clinical trials, little is known about the long-term clinical course of treatment-seeking SUD patients with comorbid ADHD. Aims: This paper presents the protocol and baseline clinical characteristics of the International Naturalistic Cohort Study of ADHD and SUD (INCAS) designed and conducted by the International Collaboration on ADHD and Substance Abuse (ICASA) foundation. The overall aim of INCAS is to investigate the treatment modalities provided to treatment-seeking SUD patients with comorbid ADHD, and to describe the clinical course and identify predictors for treatment outcomes. This ongoing study employs a multicentre observational prospective cohort design. Treatment-seeking adult SUD patients with comorbid ADHD are recruited, at 12 study sites in nine different countries. During the follow-up period of nine months, data is collected through patient files, interviews, and self-rating scales, targeting a broad range of cognitive and clinical symptom domains, at baseline, four weeks, three months and nine months. Results: A clinically representative sample of 578 patients (137 females, 441 males) was enrolled during the recruitment period (June 2017-May 2021). At baseline, the sample had a mean age (SD) of 36.7 years (11.0); 47.5% were inpatients and 52.5% outpatients; The most prevalent SUDs were with alcohol 54.2%, stimulants 43.6%, cannabis 33.1%, Abstract Background: Substance use disorders (SUD) often co-occur with attention deficit hyperactivity disorder (ADHD). Although the short-term effects of some specific interventions have been investigated in randomized clinical trials, little is known about the long-term clinical course of treatment-seeking SUD patients with comorbid ADHD. Aims: This paper presents the protocol and baseline clinical characteristics of the International Naturalistic Cohort Study of ADHD and SUD (INCAS) designed and conducted by the International Collaboration on ADHD and Substance Abuse (ICASA) foundation. The overall aim of INCAS is to investigate the treatment modalities provided to treatment-seeking SUD patients with comorbid ADHD, and to describe the clinical course and identify predictors for treatment outcomes. This ongoing study employs a multicentre observational prospective cohort design. Treatment-seeking adult SUD patients with comorbid ADHD are recruited, at 12 study sites in nine different countries. During the follow-up period of nine months, data is collected through patient files, interviews, and self-rating scales, targeting a broad range of cognitive and clinical symptom domains, at baseline, four weeks, three months and nine months. Results: A clinically representative sample of 578 patients (137 females, 441 males) was enrolled during the recruitment period (June 2017-May 2021). At baseline, the sample had a mean age (SD) of 36.7 years (11.0); 47.5% were inpatients and 52.5% outpatients; The most prevalent SUDs were with alcohol 54.2%, stimulants 43.6%, cannabis 33.1%, and opioids 14.5%. Patients reported previous treatments for SUD in 71.1% and for ADHD in 56.9%. Other comorbid mental disorders were present in 61.4% of the sample: major depression 31.5%, post-traumatic stress disorder 12.1%, borderline personality disorder 10.2%. Conclusions: The first baseline results of this international cohort study speak to its feasibility. Data show that many SUD patients with comorbid ADHD had never received treatment for their ADHD prior to enrolment in the study. Future reports on this study will identify the course and potential predictors for successful pharmaceutical and psychological treatment outcomes

Barriers to implementation of treatment guidelines for ADHD in adults with substance use disorder

Attention deficit hyperactivity disorder (ADHD) is common among adult patients with a substance use disorder, yet often goes undetected. This is a qualitative study to explore implementation barriers to a guideline developed in Belgium for the recognition and treatment of ADHD in adult patients with substance use disorder and to gain a better understanding of the strategies to overcome these barriers. Focus groups were conducted with caregivers and patients to explore experiences with comorbid substance use disorder and ADHD. The barriers reported in these focus groups became the subject of further study in focus groups with addiction professionals (physicians, psychiatrists, and psychologists) who had tried the guideline and with psychiatrists specializing in addiction but without experience with ADHD. Our analysis revealed a number of barriers to the implementation of this guideline, including lack of information from the family, pressure from patients and caregivers to make an ADHD diagnosis, and the potential for abuse of ADHD medication. Furthermore, diagnostic instruments for ADHD have not been validated in people with substance use disorder. Although patients with ADHD are usually treated in an outpatient setting, patients with ADHD comorbid with substance use disorder are difficult to identify in an outpatient setting for various reasons. Finally, there is a lack of specific ADHD expertise in substance use treatment organizations. Despite the availability of an approved guideline for recognizing and treating adult ADHD in patients with a substance use disorder, underdiagnosis and inadequate treatment still persist. As in general substance use treatment, medication only plays a supportive role in the treatment of substance use disorder with comorbid ADHD. An integrated approach and further improvements in the competence of practitioners may help to reduce the resistance to diagnosing ADHD in substance use treatment centers. Practitioners who specialize in addiction medicine and therapists without medical education view the problem from different perspectives and therefore each group needs specific information and training. Targeted interventions need to be developed to keep these patients in treatmen

Guideline for screening, diagnosis and treatment of ADHD in adults with substance use disorders

Currently there is no guideline for the screening, diagnosis and treatment of adult attention deficit/hyperactivity disorder (ADHD) in patients with a substance use disorder (SUD). The aim was to develop such a guideline, starting out from a systematic review and based on the methodology of the Scottish Intercollegiate Guideline Network (SIGN). Due to the lack of scientific evidence on some of the topics, the guideline is a combination of evidence based and practice based recommendations. Given the high prevalence of ADHD in treatment seeking SUD patients and the availability of valid screening instruments, all treatment seeking SUD patients should be screened for ADHD. Diagnosis of ADHD should be based on clinical observation and history taking, including informant data. Integrated treatment of ADHD and SUD is recommended, including pharmacotherapy, psycho-education, coaching, and cognitive behavioral therapy (CBT). The lack of scientific data and the overall lack of expertise in the field are significant obstacles to the implementation of the guideline. Intensive training programs in the substance abuse sector need to be organized to implement these guideline