The Patient’s Perspective on the Link Between ADHD and Substance Use

Abstract

Objective: The primary aim of this study was to investigate how adult individuals with ADHD perceive the role of alcohol and drugs in their lives. A secondary aim was to identify factors that those individuals consider useful in the treatment and prevention of co-occurring ADHD and substance use disorders (SUDs). Method: A qualitative interview study with ADHD outpatients (n = 14) at a psychiatric clinic. Data were analyzed based on pre-defined areas of interest using a deductive content analysis method. Results: The yearning for belongingness was identified as an important driving force underlying substance use. The participants felt that alcohol/drugs helped them being normal and thus respected and accepted. Early diagnosis of ADHD was perceived essential to avoid SUD. Conclusion: Adults with ADHD may have strong rational and emotional reasons for the use of alcohol and drugs. When planning for the treatment of adult ADHD, investigation of personal reasons for alcohol/drug use deserves a place.

Keywords

adult ADHD substance abuse reasons for co-occurrence qualitative

Introduction

The co-occurrence of ADHD and substance use disorder (SUD) is a prevalent phenomenon that has been demonstrated in numerous studies over the past decade (Arias et al., 2008; Bernardi et al., 2012; Gudjonsson, Sigurdsson, Sigfusdottir, & Young, 2012; Lee, Humphreys, Flory, Liu, & Glass, 2011; Nogueira et al., 2014; Ohlmeier et al., 2008; van Emmerik-van Oortmerssen et al., 2012). In individuals with ADHD, substance use problems are generally of a more serious character: Not only do the disorders have an earlier onset and a more severe course, but treatment outcomes are poorer as well (Arias et al., 2008; Kollins, 2008). Although highly co-occurring, the specific nature of the link between ADHD and SUD remains unclear. In one of the few studies in this area, persons with ADHD mainly used stimulants for other reasons than the euphoric effect, but the researchers were unable to present what those reasons were (Wilens et al., 2007).

Several explanations for the common co-occurrence have been suggested. Neurobiological research has observed a significant genetic predisposition for SUD in patients with ADHD in which the hyperactivity component in ADHD shares a common genetic background with that of alcohol dependence (Edwards & Kendler, 2012). Conduct disorder (CD), commonly associated with ADHD, has been suggested as a mediating factor for the increased risk of a SUD (Flory & Lynam, 2003; Nogueira et al., 2014; Serra-Pinheiro et al., 2013). Other studies, however, noted a direct link between ADHD and SUD when controlling for CD (Arias et al., 2008). Self-medication of ADHD symptoms and personality factors associated with ADHD such as impulsivity are other possible explanations (Arias et al., 2008; Wilens et al., 2007). A recent study investigating differences in the expression of impulsivity, anger, and aggression in ADHD, borderline personality disorder (BPD), and comorbid ADHD–BPD reported that ADHD and ADHD–BPD patients showed a higher level of impulsivity than BPD and controls (Prada et al., 2014). Furthermore, comorbid ADHD–BPD patients exhibited higher levels of SUD and more pronounced aggression than the other groups. Another study (Roberts, Peters, Adams, Lynam, & Milich, 2014) examined the relation among ADHD symptoms such as hyperactivity and impulsivity, substance use rates, and personality processes associated with impulsive behavior in a group of young adults. Here, hyperactive and impulsive symptoms were found to be associated with alcohol and nicotine use, whereas inattentive symptoms were only associated with alcohol use. Data suggesting that comorbid ADHD and SUD are associated with a more severe course of substance use and with social and psychiatric impairment have also been described (Moura et al., 2013).

Yet, the link between ADHD and substance use has not been studied from the patient’s perspective. There is a lack of studies focusing on experiences and thoughts of individuals with ADHD and SUD as expressed in their own words.

Qualitative studies of persons with psychiatric disorders and SUD are scarce, but the few available studies have pointed out that alcohol/drug habits in persons with psychiatric disorders may be of a particular kind. In an interview study with severely mentally ill substance users, a number of unique high-risk situations for drug use were identified (Bradizza & Stasiewicz, 2003). Two of these high-risk situations were interpersonal conflicts and loss of appetite. In another interview study, patients with bipolar disorder and SUD reported that they trusted their own drug experiences more than they trusted the advice of staff members, suggesting that they will only accept advice if it fits with their own personal experiences (Healey, Peters, Kinderman, McCracken, & Morriss, 2009). In an interview study with young female psychiatric patients, drinking alcohol was presented as a means of self-harm (Nehlin, Fredriksson, & Öster, 2013).

One factor that is essential for successful treatment is that the patient feels that the caregiver understands his or her needs (Cooley & Lajoy, 1980). Thus, caregivers may take general benefits from studies in which individuals share their experiences and thoughts. From a scientific point of view, such information may lead to the forming of new hypotheses regarding the reasons for the strong link between ADHD and SUD.

The primary aim of this study was to investigate how adult individuals with ADHD perceive the role of alcohol and drugs in their lives, in particular in relation to their ADHD symptoms. A further aim was to identify factors that individuals with ADHD consider useful in the treatment and prevention of co-occurring ADHD and SUD.

Method

This study was explorative and descriptive with a qualitative approach. A qualitative content analysis may be executed in an inductive manner by which themes are created without the use of theories or concepts, or in a deductive manner whereby themes are pre-defined (Rhodes & Coomber, 2010). A semi-structured interview with open-ended questions was used to capture informants’ perceptions as well as their experiences and feelings (Patton, 2002). Areas of interest, based on theory and clinical expertise, were defined by the present authors. Those areas were as follows: (a) the role of alcohol/drugs in relation to ADHD symptoms, (b) wanted and unwanted effects of alcohol/drugs on ADHD symptoms, (c) risk situations for alcohol/drug use specific for persons with ADHD, and (d) recommendations for treatment and prevention of co-occurring alcohol/drug problems and ADHD as perceived by persons with ADHD. Because SUD normally is most intensive during the younger years, we aimed at interviewing young persons (<30 years of age) with recent SUD experiences.

Data Collection

Data were collected among individuals with an ongoing outpatient contact at the Department of Psychiatry, Uppsala University Hospital, Sweden. They were invited by their ordinary caregiver to take part in the study according to the following criteria: (a) ADHD diagnosis or under investigation because of severe ADHD symptoms, (b) ongoing or former alcohol/drug use as they themselves defined problematic, and (c) below 30 years of age.

Informants were offered to choose the location for the interview (all chose the researchers’ office at the hospital). All interviews, which lasted for 25 to 40 min, were recorded. The interview sessions were consciously kept short to avoid strain on core ADHD symptoms, such as attention problems. Participants were offered a break in the middle of the interview.

An interview guide was developed to ensure that the areas of interest be covered in all interviews. The interview guide was piloted on two persons, which led to minor adjustments. The included questions were related to the areas of interest previously described. The interviews were conducted on a subject-by-subject basis, and the areas of exploration were graphically drawn on a sheet of paper. The informants were asked during the interview to narrate their own story; in this regard, prompting questions were used to explore the informants’ perceptions, experiences, and feelings in more depth. The interview guide is available from the first author on request.

All interviews were carried out by the first author (C.N.), who has 25 years of experience from social work with problematic youth and within psychiatric outpatient care. C.N. has received advanced training in qualitative data collection. The interviews were transcribed verbatim and all were used in the analysis.

Data Analysis

In this study, deductive analysis, directed content analysis, was performed (Hsieh & Shannon, 2005). The analyses were performed in the following steps. First, key concepts as initial coding categories were identified from the pre-defined areas of interest. Second, operational definitions for each category were determined based on the areas of exploration in the interviews. Third, interviews were listened to and read through several times by the authors, always bearing in mind the aims of the study. Fourth, sentences or paragraphs containing information corresponding to the categories were identified, analyzed, and placed in the relevant category in the coding scheme. The co-authors discussed the coding of the data until consensus was achieved and the categories were confirmed. Fifth, to increase the rigor of the analysis, the interview texts were read again and the categories were compared and validated against the whole text. See Table 1 for an illustration of the analysis process.

Table 1.

Examples of the Coding Scheme in the Directed Content Analysis.

Sentences, paragraphs	Operational definition	Category
“(when on drugs) I could run my daily life. I was accepted, I felt normal.”	Role of alcohol/drugs in life	Reasons for alcohol/drug use
“I felt . . . whole, in a way. I could act more as a human being.”
“I think, in some way you want to push away all these thoughts that are spinning.”	Positive sides of alcohol/drugs	Wanted effects
“I could sit down and crochet and such things.”
“Just because I can. If there were any (alcohol), I wanted it.”	Specific risk situations for the intake of alcohol/drugs	Particular risk situations

The study was approved by the Research Ethics Committee of Uppsala County (Dnr 2012/376).

Results

In all, 16 persons accepted to take part in the study. Two of them never turned up for the interview, leaving a final sample of 14 participants of which 8 were women and 6 were men. Their mean age was 29.6 ± 7.8 years. None was married but five were currently in a relationship. Five had children and two of those who had children were in a relationship. None lived with the other parent of their child/children. The participants’ demographics are further described in Table 2.

Table 2.

Demographic Characteristics of the Participants.

Variable
Female/male, n	8/6
Mean age ± SD (years)	29.6 ± 7.8
Median age (years)	25.5
Currently in a relation, n	5
Have children, n	5
ADHD diagnosis	12
Under investigation	1
ADD	1
Employment status
Study or work	9
Unemployed	3
Sick leave	2
Additional diagnoses
Bipolar disorder	1
Depression	1
Borderline PD + PTSD	1
Anorexia + OCD	1
Drug of choice
Alcohol	10
Amphetamine	3
Cannabis	1

Note. ADD = attention deficit disorder; PD = personality disorder; PTSD = post-traumatic stress disorder; OCD = obsessive-compulsive disorder.

The results are presented under the coding categories with verbatim quotes to illustrate the findings.

Role of Alcohol/Drugs

In this category, information about the key function of alcohol/drugs was collected. Participants emphasized the important impact alcohol/drugs had had in their life:

All my life I felt there is something missing. I always craved for something. And when I tried alcohol for the first time . . . ah, that was the last piece of the puzzle. (A1)

Everything changed . . . I became another person. (A12)

It (amphetamine) meant everything. It was my husband, sort of. (A7)

Using alcohol/drugs was described not just as a way of minimizing symptoms and normalizing thoughts, emotions, and behavior. The participants talked of a way of becoming “normal.” When being able to perform everyday activities, participants reached a feeling of belonging and acceptance from those in their immediate environment. Being normal helped attain acceptance that had long been sought after:

Above all, it helped me to become patient. I did normal things, at a normal speed. I could work, I could read books for the kids . . . It was all about getting accepted. To belong and to be accepted as you are. I never felt accepted anywhere, neither in my family nor at school or anywhere. (A10)

About belonging . . . I wasn’t that nice girl my parents wanted, I always messed things up. I always heard “We can’t go anywhere with you” . . . all that. And when on drugs I could sit still, I was normal, like people wanted me to be. I have never been accepted by my family, but then I thought, maybe now they want to be with me. (A7)

Wanted Effects

All participants described a number of wanted effects from alcohol/drugs, particularly regarding their ADHD symptoms. The major desired effect was a sense of calm and a relief from restlessness and agitation. Activities of normal daily life, such as working, taking care of children, and cleaning, could be executed in a better way.

Everything worked much better . . . I mean, I could read a book. I could fill in the papers as I should, I could take care of my job, I could do anything. (A8)

Although many participants felt that they were quite outgoing, alcohol/drugs were perceived to improve social interaction by the filtering of unwanted sensations. The participants described the shift as instant, from experiencing a “chaos of mind” into feeling socially capable when reaching intoxication.

It was difficult for me to meet several people at the same time . . . I said the wrong things although I meant something else . . . So I took a minimum dose of amphetamine in order to do my job and manage meetings with my clients. (A13)

When several others talk, I can’t filter what one says from what someone else says. Everything is like a blur. I have to talk with one person at a time and concentrate on that person. And with alcohol, all that got easier, to follow all conversations. (A1)

Unwanted Effects

The participants’ descriptions of unwanted effects of alcohol/drug use were mainly of a social character (e.g. unemployment, debts, criminality) and not specifically related to ADHD symptoms. Many of the participants, however, reported problems with lowered impulse control and increased aggression. The more alcohol/drug consumed, the more acute the impulse control problems were.

I get very strong impulses, I always have. So, I know I have to keep my plan. And when I’m drunk, I can’t do that, and so my ADHD takes over. (A2)

I am always sort of wound up. And if I drink too much, I get even worse. And then I take too much medication, although I’m not supposed to. (A5)

Risk Situations

There were few specific situations that triggered alcohol and drug intake; it was rather described as a way of handling feelings of boredom or feelings of well-being. Impulsivity in general was often mentioned as a risk factor although not connected with a specific risk situation:

When you have ADHD and you are a person that gets easily bored, basically, anything could be a risk factor. (A11)

Well-being. It’s a terribly dangerous thing. If I feel good, I want to feel better. It’s automatic. (A10)

Impulsivity is really a great part of ADHD, you just don’t think about what might happen if you do things. (A3)

Participants with co-occurring mood disorders exemplified a need for relief from depressive thoughts as a risk situation:

Drinking was more about my other disorder (bipolar disorder). When I felt really low, I started to drink. And then things got a bit easier. (A4)

Factors Considered Useful for Treatment and Prevention

A number of factors of importance for treatment and prevention of co-occurring ADHD and SUD were presented. In retrospect, many participants believed that they could have avoided SUD if their ADHD had been diagnosed in early age. It would have helped them become understood as individuals with resources, not just misfits. Medication, building a structured daily life, and information about ADHD were interventions mentioned that could have helped them avoid situations leading to the development of SUD:

If you know from early on that you have ADHD, then maybe you can get a different kind of support. (A9)

If only I had gotten my diagnosis much earlier. And if all this had been stopped earlier, maybe I hadn’t come to go so far. Since I got my medication, everything has changed substantially. (A8)

Medication was perceived by some participants as an important help in dealing with substance use problems:

I didn’t have medication before. And then it easily happens that you get off the track, come into the wrong scene. (A4)

Nowadays, my medicine does exactly what alcohol used to do for me. So I don’t need that any more. (A1)

Others reported medium effects or were reluctant to using medication.

It helps, but only up to a certain limit. But it does do something, absolutely, and it helps me. (A13)

I used to take medicine for my ADHD. I didn’t feel well from it. I think it is of importance that I have abused amphetamine. So I get some feeling of that back, and it gives me a lot of anguish. (A11)

The participants regarded a well-structured everyday life, including a meaningful occupation, as essential. Learning about ADHD could be of great help:

I didn’t have routines to follow at all. I mean—in the morning you first do this, then that . . . I think you need to have something to follow, it makes you calmer. Then you don’t need to drink. (A5)

It was important to learn to understand it and to process the information. Maybe not to medicate, but to understand it. Those lectures have given me a better picture of myself. I have begun to understand myself, for real. The lectures were the best of it all. (A13)

Psychiatric caregivers were advised to ask for individual motives for alcohol and drug use instead of ignoring such problems or make them a reason for exclusion from ADHD treatment:

If you get the word “abuse” in your patient records, you’re out. They judge you from that, and then you can’t get your necessary medication. Instead, they should incorporate it in the treatment . . . You can’t just break off the behavior and believe it’s going to disappear. You have to take care of the reasons, too . . . They should have asked me about my reasons, about the history of my life. Then they should have based my treatment on that. (A1)

You should ask the person why he does it. Everyone has his reasons. (A4)

The Link Between ADHD and Substance Use

The participants described how they used alcohol/drugs as a means to regulate feelings and thoughts and to filter unwanted sensations. This had positive consequences such as the ability to perform activities of daily life and being more socially capable, expressed by the participants as being normal. To achieve normality was a way to become accepted by others and through that reach a feeling of belonging. In Figure 1, suggested associations are graphically illustrated.

Figure 1.

An illustration of the perceived reasons for substance use.

Discussion

This is the first study to focus on the link between ADHD and SUD as perceived and expressed by persons with ADHD. The yearning for belongingness was identified as an important driving force underlying the use of alcohol and drugs among adults with ADHD. Using alcohol/drugs helped participants become normal, that is, capable of performing the stuff of normal adult life as expected from any responsible and social person. Performing activities, such as taking care of children, being able to work, and to pay bills was the most essential component of perceived normality. In performing such activities, participants felt that they were normal and thus were respected and accepted as a part of their society. By feeling normal, they experienced belongingness and acceptance. In a focus group study of persons with ADHD, a desire to become normal was also mentioned as a reason for alcohol and drug use (Brod, Pohlman, Lasser, & Hodgkins, 2012). In contrast to young boys with ADHD expressing a desperate wish to belong and blaming themselves for being excluded from social life (Young, Chesney, Sperlinger, Misch, & Collins, 2009), the adult participants in our study described efforts that could have helped them during early years. Those efforts could have helped them avoid alcohol/drug problems and thus given them a greater opportunity to experience belonging. The need to belong is considered one of the most fundamental of all personality processes, of which the present findings are an illustration (DeWall, Deckman, Pond, & Bonser, 2011).

Impulsivity as a personality trait has been presented as a major cause in the development of SUD (Edwards & Kendler, 2012). Impulsivity, a core symptom of ADHD, could lead the individual to try substances without considering their consequences. In our interviews, various aspects of impulsivity leading to substance use were described, among them the impatience when just feeling well. Similar commentaries were found in the focus group study previously mentioned (Brod et al., 2012).

Experienced clinicians have suggested that self-medication is a major explanation for co-occurring ADHD and SUD (Kalbag & Levin, 2005; Söderpalm, 2012). In search of support for the self-medication hypothesis, Wilens et al. used questionnaires in adolescents with and without ADHD (Wilens & Upadhyaya, 2007). The researchers found partial support for this hypothesis with 34% of their participants reporting the use of drugs to help alleviate mood or sleep problems. It could not be pointed out, however, that such reasons were specific for adolescents with ADHD. In our study, self-medication was reported in the sense that participants used alcohol/drugs to attenuate their ADHD symptoms and hence felt more normal. In cases of co-existing mood disorders, the alcohol/drugs were also used to alleviate those symptoms.

The present results underline the importance of early diagnosis and treatment of ADHD in the prevention of co-occurring problems, as has previously been noted (Ohlmeier et al., 2008). The participants perceived that if their ADHD had been dealt with early in their life, for example, by receiving medication, training, or simply understanding, many of their subsequent problems could have been avoided. This was also evident in a qualitative study where adults, newly diagnosed with ADHD, felt that they had wasted years of their lives without a diagnosis (Young, Bramham, Gray, & Rose, 2008). Still, medication may not be as efficient as wished for. Participants in this study reported having medium effects or that they were reluctant to use it, for example, because it reminded them of their previous, problematic period of intensive drug use. For others, again, medication had provided an important platform for a new direction in life. Participants with ADHD in focus groups were generally satisfied with their medication, but a majority took their medication based upon their own interpretation of their symptoms and not in compliance with their prescriptions (Brod et al., 2012).

The participants in this study recommended caregivers to actively ask for alcohol/drug use and the individual’s reasons for using it. In a recent review, the need is underscored for a systematic and comprehensive assessment of any substance use in ADHD patients to improve the assessment, diagnosis, and management of dual problems (Martinez-Raga, Szerman, Knecht, & de Alvaro, 2013). It is common for ADHD treatment programs to exclude patients with ongoing SUD. There is little evidence from randomized controlled trials of the efficacy of stimulant pharmacotherapy to treat co-occurring ADHD and SUD. Yet, a recent review of the current literature concludes that medication with methylphenidate has been well tolerated in this group of patients (although not effective in reducing SUD) and that no trials report worsening of drug use (Konstenius, 2013). In this study, patients reported that the risk of losing ADHD treatment led them to conceal their substance use problems rather than to actively deal with them. They recommended caregivers to include treatment of SUD as part of ADHD treatment. We believe that receiving ADHD treatment may constitute a window of opportunity for dealing also with substance use problems. Our results suggest that asking about the role of alcohol/drugs in the patient’s life would be of help, particularly in the early phases of treatment. Asking about the role of alcohol/drugs can introduce discussions of alternative strategies.

A somewhat unexpected finding is that, for some individuals, alcohol was effective in reducing ADHD symptoms of inattention, described as the filtering of impressions. Normally, amphetamine is described as having this function. However, studies have shown that alcohol may affect attentional bias in social drinkers (Nikolaou, Field, & Duka, 2013). An acute alcohol dose was also shown to increase attentional bias in adults with ADHD (Roberts, Fillmore, & Milich, 2012). Why alcohol attenuates ADHD symptoms in some individuals needs further study, including neurobiological aspects.

Strengths and Limitations

This is an exploratory study and therefore interpretations of the data should be considered within the context of qualitative research. The findings cannot be generalized but rather can contribute to new insights concerning the link between adults with ADHD and their use of alcohol and drugs. The insider perspective, describing experiences of persons with ADHD in relation to alcohol and drugs, is a strength of this study. The participants were not given the questions before the interview and thus could not prepare in advance. Still, they had no difficulties expressing their thoughts and feelings, which provided a source of information-rich data. The interviewer’s (C.N.) many years of experience from social work and psychiatric care, together with the form of the interviews (i.e., question areas graphically drawn and questioning on a subject-by-subject basis), helped facilitate data collection. These procedures strengthen the validity and credibility of the study (Graneheim & Lundman, 2004).

We are aware of some limitations. The use of directed content analysis with the pre-determined codes might result in finding evidence that is supportive rather than nonsupportive of the codes. Thus, to achieve confirmability of trustworthiness, the co-authors were involved in alternative coding and discussions of the data. Pre-defined areas of interest may also have prevented the participants to tell their own story by getting cues to answer. Another limitation is that alcohol was the main drug of choice among the participants, and it is possible that responses would have differed had we actively recruited, for example, cannabis users. Furthermore, interviews with significant others could have contributed to a broader understanding of the situations in daily life (Young, Gray, & Bramham, 2009). However, the focus in this study was the insider perspective, how persons with ADHD describe their own experiences and thoughts.

Conclusion

Adults with ADHD may have strong rational and emotional reasons for the use of alcohol and drugs. Using alcohol and drugs might help them perform everyday life tasks, which makes them feel normal and gives them a sense of belonging. When planning for the treatment of ADHD in adults, the investigation of personal reasons for alcohol/drug use deserves a place.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received financial support from the Municipal Research Fund of Uppsala County and the Nasvell Fund for Psychiatric Research for the research of this article.

Author Biographies

Christina Nehlin, PhD, is a researcher at Uppsala University, Department of Neuroscience, Psychiatry. Her research focuses on co-occurring mental health and substance use problems.

Fred Nyberg, professor at Uppsala University, Department of Pharmaceutical Biosciences, conducts biological research on drug dependence.

Caisa Öster, PhD, is a senior lecturer and researcher at Uppsala University, Department of Neuroscience, Psychiatry. Her research focuses on impact of psychiatric morbidity in adaptation after injury and relationships between mental health and quality of life.

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