Psychiatric comorbidity in adults with attention-deficit/hyperactivity disorder (ADHD)

European Archives of Psychiatry and Clinical Neuroscience - Attention-deficit/hyperactivity disorder (ADHD) is a chronic, lifelong disorder with childhood-onset, which seriously impairs the...     

Psychiatric comorbidity in adults with attention-deficit/hyperactivity disorder (ADHD)

Attention-deficit/hyperactivity disorder (ADHD) is a chronic, lifelong disorder with childhood-onset, which seriously impairs the affected adults in a variety of daily living functions like educational and occupational functioning, partnership and parenting. ADHD is associated with a high percentage of comorbid psychiatric disorders in every lifespan. In adulthood between 65-89% of all patients with ADHD suffer from one or more additional psychiatric disorders, above all mood and anxiety disorders, substance use disorders and personality disorders, which complicates the clinical picture in terms of diagnostics, treatment and outcome issues. The present overview provides information of comorbid psychiatric disorders in adults with ADHD, underlying associations and clinical implications.     

Treatment of adults with attention-deficit/hyperactivity disorder

This review focuses on the treatment of attention deficit hyperactivity disorder (ADHD) in adults. It briefly addresses prevalence, diagnostic and differential diagnostic issues specific to adults. Stimulant medication, non-stimulant medication, and psychosocial treatments are thoroughly reviewed. For each class of medication possible mechanism of action, efficacy and side effects are summarized. Special attention is given to the pharmacological treatment for patients with adult ADHD and various comorbidities. In summary, stimulant medications are most effective and combined medication and psychosocial treatment is the most beneficial treatment option for most adult patients with ADHD.     

Treatment of adults with attention-deficit/hyperactivity disorder

This review focuses on the treatment of attention deficit hyperactivity disorder (ADHD) in adults. It briefly addresses prevalence, diagnostic and differential diagnostic issues specific to adults. Stimulant medication, non-stimulant medication, and psychosocial treatments are thoroughly reviewed. For each class of medication possible mechanism of action, efficacy and side effects are summarized. Special attention is given to the pharmacological treatment for patients with adult ADHD and various comorbidities. In summary, stimulant medications are most effective and combined medication and psychosocial treatment is the most beneficial treatment option for most adult patients with ADHD.     

Cognitive control in adults with attention-deficit/hyperactivity disorder

The objective of the present study was to investigate the ability of adults with Attention-Deficit/Hyperactivity Disorder (ADHD) to direct their attention and exert cognitive control in a forced instruction dichotic listening (DL) task. The performance of 29 adults with ADHD was compared with 58 matched controls from the Bergen Dichotic Listening Database (N > 1500). Participants in the Bergen DL task listen to and report from conflicting consonant-vowel combinations (two different syllables presented simultaneously, one to each ear). They are asked to report the syllable they hear (non-forced condition), or to focus and report either the right- or left-ear syllable (forced-right and forced-left condition). This procedure is presumed to tap distinct cognitive processes: perception (non-forced condition), orienting of attention (forced-right condition), and cognitive control (forced-left condition). Adults with ADHD did not show significant impairment in the conditions tapping perception and attention orientation, but were significantly impaired in their ability to report the left-ear syllable during the forced-left instruction condition, whereas the control group showed the expected left-ear advantage in this condition. This supports the hypothesis of a deficit in cognitive control in the ADHD group, presumably mediated by a deficit in a prefrontal neuronal circuitry. Our results may have implications for psychosocial adjustment for persons with ADHD in educational and work environments.     

Disentangling deficits in adults with attention-deficit/hyperactivity disorder

CONTEXT: A lack of inhibitory control has been suggested to be the core deficit in attention-deficit/hyperactivity disorder (ADHD), especially in adults. This means that a primary deficit in inhibition mediates a cascade of secondary deficits in other executive functions, such as attention. Impaired stopping has been claimed to support the inhibition hypothesis. However, executive functions such as inhibition and attention are hard to disentangle. OBJECTIVE: To use event-related potentials in adult patients with ADHD to show that impaired stopping is associated with abnormalities of attention. DESIGN: The stop signal task was presented to 24 adults with ADHD combined subtype and 24 controls. Stop event-related potentials are distorted by overlap from event-related potentials to other stimuli in close temporal proximity, but we applied a method (Adjar level 2) to effectively remove this overlap. RESULTS: In line with an inhibitory control deficit, the stop signal reaction time was longer in adults with ADHD (F(1,46) = 7.12, P<.01) whereas there was no significant difference for go stimulus reaction time. Overlap-free stop event-related potentials revealed smaller stop P3s in adults with ADHD (F(1,44) = 4.20, P<.05). In children with ADHD, this has been interpreted to reflect deficient inhibitory control. However, controls were also found to have larger early responses in the auditory cortex (N1) when stop signals resulted in successful stops, relative to failed stops, signifying increased attention (F(1,23) = 11.88, P<.01). This difference was completely absent in adults with ADHD. CONCLUSIONS: Disturbed attentional processing of the stop signal contributed to impaired stopping in adults with ADHD. This finding may have implications for treatment.     

The diagnostic validity of attention-deficit/hyperactivity disorder

Despite considerable research, the validity of attention-deficit/hyperactivity disorder (ADHD) remains controversial. This paper summarizes the results of a comprehensive review of the internal and external validity of ADHD as defined in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Results indicate that for most individuals DSM-IV ADHD is a valid disorder in the sense that it is associated with significant impairment in social, academic, and occupational functioning and increased risk of accidental injury across the life span. Additional research is needed, however, to clarify the diagnostic validity of the hyperactive-impulsive type and the discriminant validity of the combined and inattentive subtypes. Other areas in need of further study include potential modifications to the diagnostic conceptualization of the inattentive subtype, developmental trajectories of the subtypes, and methods to address cross-informant diagnostic inconsistencies. Such research is likely to benefit from an etiologically informed approach to examining heterogeneity both across and within subtypes.     

Physiological and psychological stress responses in adults with attention-deficit/hyperactivity disorder (ADHD)

According to self-report and unsystematic observational data adult patients with attention-deficit/hyperactivity disorder suffer from increased vulnerability to daily life stressors. The present study examined psychological and physiological stress responses in adult ADHD subjects in comparison to healthy controls under laboratory conditions. Thirty-six subjects (18 patients with DSM-IV ADHD diagnosis, 18 sex- and age-matched healthy controls) underwent the Trier Social Stress Test (TSST; Kirschbaum, C., Pirke, K.-M., Hellhammer, D.H., 1993. The “Trier Social Stress Test”—a tool for investigating psychobiological stress responses in a laboratory setting. Neuropsychobiology 28, 76–81), a standardized psychosocial stress protocol which contains a stress anticipation phase and a stress phase with a free speech assignment and subsequent performance of a mental arithmetic. Physiological stress measures were salivary cortisol as an indicator of the HPA axis, heart rate (HR), and time- and frequency-domain heart rate variability (HRV) parameters. Subjective stress experience was measured via self-report repeatedly throughout the experimental session. In line with previous theoretical and empirical work in the field of childhood ADHD, it was hypothesized that the ADHD and control group would exhibit comparable baseline levels in all dependent variables. For ADHD subjects, we expected attenuated responses of the physiological parameters during anticipation and presence of the standardized stressor, but elevated subjective stress ratings. Hypotheses were confirmed for the baseline condition. Consistent with our assumptions in regard to the psychological stress response, the ADHD group experienced significantly greater subjective stress. The results for the physiological variables were mixed.

While ADHD subjects revealed an attenuated HR during the stress phase, no significant group differences were found for the other parameters, although a trend was observed for both the low frequency/high frequency (LF/HF) ratio of the HRV power spectral analysis and salivary cortisol (the latter possibly indicating generally lower cortisol levels in ADHD subjects). In summary, the present findings are the first to demonstrate a significant alteration of a specific physiological stress measure (HR) and, more clearly, of psychological aspects of the stress response in adults suffering from ADHD. In regard to the physiological stress response, it is recommended that future studies employ larger sample sizes and a more comprehensive range of physiological stress parameters. Additionally, the issue of transferability of laboratory results to real life stressors needs to be addressed.     

Impact of comorbidity in adults with attention-deficit/hyperactivity disorder

Persistence of attention-deficit/hyperactivity disorder (ADHD) into adulthood and male-to-female ratios of this disorder in childhood and adulthood have been controversial issues in the ADHD diagnosis in adults. Research has resolved these controversies and in turn provided support for the validity of the diagnosis in adults. Support for the diagnosis can also be found in data that show the lifetime prevalence rate for comorbid conditions such as antisocial disorders, mood and anxiety disorders, and substance abuse disorders to be consistent across pediatric and adult populations with ADHD. These coexisting conditions add not only to the impairment associated with ADHD in adults but also to the disorder's economic burden, the extent of which is currently unknown. However, adults with the disorder, like children, probably have higher health care use and costs than people without the disorder. Little, too, is known about the social cost of ADHD, but if left untreated, the impact may be substantial. Research to determine the occupational costs associated with ADHD is ongoing, but until that and other cost-of-illness data are available, studies on the economic costs of the comorbid conditions depression, anxiety, and substance abuse and dependence may be used to make suppositions about the economic impact of ADHD in adults. More studies are needed on the outcomes of adults with this disorder, especially cost-of-illness studies.     

Neuropsychological function in adults with attention-deficit/hyperactivity disorder.

This article reviews the current state of the literature pertaining to the neuropsychological dysfunctions that are found in children and adults with attention-deficit/hyperactivity disorder (ADHD). Be-cause considerable controversy has existed about the nature and validity of adult ADHD, this article will aid clinicians in develop-ing a better understanding of the empirical literature on neuropsychological function in ADHD throughout the lifespan.     

Characteristics of adults with attention-deficit/hyperactivity disorder and past conduct disorder

Objective: DSM‐IV Attention‐deficit/hyperactivity disorder (ADHD) comorbid with DSM‐IV conduct disorder (CD) in childhood/adolescence has been proposed as a ‘distinct subtype’. The present study investigated subsequent psychopathological characteristics of this proposed subtype in adults. Method: Questionnaires were completed by 71 adults (mean age 29.6 years) with ADHD and their informants. Results: The 39 subjects with a history of past CD, when compared with the remaining subjects, were associated with significantly increased ratings of aspects of ADHD‐related impulsivity, with features of all three DSM‐IV ‘Clusters’ of personality disorders (PDs) (in particular of ‘Cluster B’ PDs) and with other psychopathology. Also, there were significant correlations between the number of endorsed past CD criteria and various self‐ratings of psychopathology. Conclusion: The results indicate the psychopathological characteristics of adults with a history of the proposed ‘ADHD with CD’ subtype. The findings are relevant to future studies of ADHD subtypes in adults.     

Assessment and diagnosis of attention-deficit/hyperactivity disorder

ADHD is the most common psychiatric disorder of childhood (3% to 5% of children) with continued morbidity into adolescence (85%) and adulthood (50% to 70%). It is a condition associated with widespread significant impairment in academic, occupational, social, and emotional functioning. It is also a condition with a broad extensive differential diagnosis as well as a high rate of comorbidity. There is no diagnostically definitive test for ADHD. Therefore, assessments for ADHD need to be comprehensive and should involve multiple domains, informants, methods, and settings. The comprehensive assessment needs to determine whether the subject has ADHD or another disorder. Thus, evaluation of various organic conditions, functional disorders, developmental status, situational, environmental, and family problems should all be explored. The clinical interview of the child and family is one of the cornerstones of the assessment process. A comprehensive medical history and examination, psychoeducational tests, and school-related evaluation, as well as a view of the child's social and emotional functioning, are also crucial. A wide array of rating scales, tests, and measures have been developed (see Table 1) to aid in the systematic standardized assessment of the various deficits associated with ADHD. None of these tests is definitive, however. Recent development of tests of executive functioning, neuroimaging, and genetics may provide more exact diagnostic guidelines in the future. Current DSM-IV criteria are phenomenologic rather than etiologic and are much more relevant and appropriate for children with ADHD compared with adolescents and adults. A comprehensive assessment involving various domains of functioning (academic, social, emotional, physical, and familial) provide not only more accurate diagnosis but also directions as to what difficulties exist and what multifaceted treatment plan is needed to produce current improvement and long-term positive outcome.     

Prediction of methylphenidate treatment outcome in adults with attention-deficit/hyperactivity disorder (ADHD)

Compulsory admission to psychiatric inpatient treatment can be experienced as disempowering and stigmatizing by people with serious mental illness. However, quantitative studies of stigma-related emotional and cognitive reactions to involuntary hospitalization and their impact on people with mental illness are scarce. Among 186 individuals with serious mental illness and a history of recent involuntary hospitalization, shame and self-contempt as emotional reactions to involuntary hospitalization, the cognitive appraisal of stigma as a stressor, self-stigma, empowerment as well as quality of life and self-esteem were assessed by self-report. Psychiatric symptoms were rated by the Brief Psychiatric Rating Scale. In multiple linear regressions, more self-stigma was predicted independently by higher levels of shame, self-contempt and stigma stress. A greater sense of empowerment was related to lower levels of stigma stress and self-contempt. These findings remained significant after controlling for psychiatric symptoms, diagnosis, age, gender and the number of lifetime involuntary hospitalizations. Increased self-stigma and reduced empowerment in turn predicted poorer quality of life and reduced self-esteem. The negative effect of emotional reactions and stigma stress on quality of life and self-esteem was largely mediated by increased self-stigma and reduced empowerment. Shame and self-contempt as reactions to involuntary hospitalization as well as stigma stress may lead to self-stigma, reduced empowerment and poor quality of life. Emotional and cognitive reactions to coercion may determine its impact more than the quantity of coercive experiences. Interventions to reduce the negative effects of compulsory admissions should address emotional reactions and stigma as a stressor.     

The consequences of attention-deficit/hyperactivity disorder in adults

Until recently, attention-deficit/hyperactivity disorder (ADHD) was a diagnosis reserved for children and adolescents as it was believed to dissipate before adulthood. New evidence, however, supports the persistence of ADHD beyond adolescence, and it is now recognized as a chronic neurobehavioral disorder in adults. Adults with ADHD have difficulties with school, work, family interactions, and social activities. Although treatments are available for adult ADHD, many patients never receive an accurate diagnosis that would afford them appropriate therapeutic intervention. If left untreated, adult ADHD can cause significant personal, social, and economic burdens that can have a negative impact on overall quality of life. This article discusses how ADHD presents in adults and the effects of the disorder on educational, occupational, interpersonal, and social functioning. Currently available treatments for ADHD in adults are also reviewed.     

Discriminant validity of the Wender Utah Rating Scale for attention-deficit/hyperactivity disorder in adults

The authors examined the factor structure and discriminant validity of the Wender Utah Rating Scale (WURS) in adults seeking evaluation for attention-deficit/hyperactivity disorder (ADHD). Three factors (Dysthymia, Oppositional/Defiant Behavior, and School Problems) accounted for 59.4% of the variance. In a stepwise discriminant function analysis, age and childhood school problems emerged as significant variables. The classification procedure correctly classified 64.5% of patients. Among those who did not have ADHD, only 57.5% were correctly classified compared with 72.1% among those with ADHD. The WURS is sensitive in detecting ADHD, but it misclassifies approximately half of those who do not have ADHD.     

Psychosocial treatments for adults with attention-deficit/hyperactivity disorder.

This article discussed some ways in which a history of failure experiences can enhance negative affect and cognitive avoidance and further impair attentional and organizational abilities associated with ADHD. Accordingly,psychosocial interventions have two targets: providing training in organizational and attentional skills while addressing patterns that motivate demand-related distress and avoidance of these skills. The authors conceptualized these interventions as creating the conditions where patients best can use existing abilities and the benefits offered by medication treatment. As rep-resented by a small but growing literature, there are encouraging signs that structured skill-building treatments of this kind offer benefit to adults with ADHD. Further research on these strategies in the context of well-controlled trials is an essential step for helping reduce disability and distress among this cohort of patients.     

Diagnosis and evaluation of adults with attention-deficit/hyperactivity disorder.

Although some areas of adult ADHD knowledge remain unclear, there isa strong sense of how to proceed with diagnosis using current DSM-IV criteria as a guide. Thorough clinical interview, aided by the use of rating scales for current symptoms and collateral information about childhood from parents or siblings, forms the backbone of the assessment. The poor psychosocial outcomes of patients with ADHD. often a consequence of unrecognized,untreated disorder manifestation, also can serve as a diagnostic indicator. Diagnostic and symptom assessment scales also can be a significant helpin diagnosing and establishing the symptoms of ADHD in adults. It is important to remember that according to DSM-IV, the cardinal criteria for making the diagnosis are the presence of sufficient current symptoms and impairment in two realms (home, school/work, and social interactions). Accordingly, adult ADHD remains a clinical diagnosis, and the clinician-administered interview remains the cornerstone of diagnostic evaluation.     

Quantitative EEG analysis in dexamphetamine-responsive adults with attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder (AD/HD) is recognized as a disorder affecting children and adolescents and has more recently been documented to continue into adulthood in a proportion of patients. One of the common treatments for AD/HD is the use of stimulant medications. Numerous studies have examined the therapeutic effects of stimulant medications in children, adolescents and adults with the disorder, reporting improvements in attention, concentration, and hyperactive and impulsive behaviours. Several studies have also examined the effects of stimulants on the electroencephalograph (EEG) of children and adolescents with the disorder, but to date, there have been no studies examining the effects of stimulant medication on the EEG of adults with AD/HD. In the present study, we aimed to replicate previous EEG findings in adults with AD/HD relative to controls and to examine whether there was any change in this profile following treatment with dexamphetamine. The EEG was recorded at rest in an eyes-open condition from 50 adults diagnosed with AD/HD and assessed as good responders to treatment, both before and after treatment with dexamphetamine, and 50 control subjects. The pre-medication results are similar to those found in previous research that compared the EEGs of adults with AD/HD and control subjects. Following medication, there was a significant reduction in slow wave activity in the AD/HD group to levels similar to those in the control group. These results suggest that changes in brain function of good responders to dexamphetamine, as reflected in the EEG, may underlie the behavioural improvements observed in the clinical setting.     

Clinical assessment and diagnosis of adults with attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder (ADHD) is a prevalent disorder in adult psychiatry, particularly in out-patient settings. There are no objective, laboratory-based tests that can establish this diagnosis. Present diagnostic criteria for ADHD are formulated primarily according to behavior in childhood, based on age inappropriate and impairing levels of hyperactivity, impulsivity and inattention. Other symptoms, such as mood instability and frustration intolerance, are not included in current criteria for ADHD, but are very prevalent in this patient group. ADHD is often comorbid with alcohol and substance abuse and other psychiatric disorders, in particular anxiety and personality disorders. Thus, the diagnostic assessment should both include a comprehensive clinical interview, rating scales for past and present symptoms and collateral information from multiple informants, as well as assessment of a broader spectrum of psychiatric and somatic conditions. As ADHD is associated with changes in brain function mediating different aspects of neuropsychological functions, assessment of those functions is important to understand the symptom patterns and to develop targeted treatment programs. Some topics for further research and for future developments of diagnostic criteria and tools are highlighted.