Network-Based Differences in Top-Down Multisensory Integration between Adult ADHD and Healthy Controls-A Diffusion MRI Study.

Prospective Follow-up Studies of ADHD: Helping Establish a Valid Diagnosis in Adults

Treatment Controversies in Adult ADHD.

FIGURE 1. Changes in cortical thickness provide one measure of brain maturation. A large longitudinal study found that for most areas of cortex, children with attention deficit hyperactivity disorder (ADHD) reach peak cortical thickness several years later than typically developing children, supporting presence of developmental delay. The rate of cortical thinning also differed between the group who continued to meet diagnostic criteria into adulthood (persistent ADHD) and those who did not (remitted ADHD). Areas of cortex in which the rate of thinning correlated with adult symptom level (green, more symptoms associated with more thinning) are approximated on medial and lateral simplified representations of cortex. An earlier study also identified multiple areas in which cortex was thinner in adults with persistent ADHD compared with controls (orange). In addition, this study noted some areas of thicker cortex in remitted ADHD when compared with persistent ADHD (blue).

Background: Attention-Deficit Hyperactivity Disorder (ADHD) is a common disorder, affecting 4% to 5% of South African children. Recent studies reveal that 30% to 70% of children continue to experience problems related to ADHD in adulthood. Adults are becoming increasingly aware of adult ADHD as a result of public awareness campaigns in the media. Their first line of action is to visit their family physician (GP), but the question that arises is whether these practitioners are ready to take on patients with ADHD. The aims of this study were to determine the familiarity, attitudes and practices of general practitioners (GPs) in South Africa with regard to ADHD in both children and adults, and whether there are differences in children and adults with regard to depression and generalised anxiety disorders as comorbid disorders. The study also briefly explored the training models of GPs in South Africa. Methods: The research questions were addressed by means of a survey approach, using quantitative measures. An e-mail message with a covering letter, explaining the purpose of the research project, provided a link to a web-based questionnaire. It was relayed to 6 704 GPs on the database of the company MEDpages, which managed the distribution. A questionnaire attached to an e-mail message was sent to all departments of Family Health at universities in the country to obtain information with regard to the training models of GPs. The questionnaire was completed by 229 respondents. The data were statistically analysed using Statistica Version 7.0. Results: The most significant outcome of the study revealed a considerable need among GPs to increase their knowledge base with regard to ADHD (87% with regard to children and 89% with regard to adults). As they were of the opinion that they should be able to diagnose and manage ADHD in both children (90%) and adults (85%) a significant need for a screening tool (83%) was also found. The GPs’ knowledge and training with regard to depression and generalised anxiety disorders were significantly more extensive with regard to adults than to children. Training with regard to ADHD in adults was almost non-existent. With regard to children the most important barriers were uninformed parents (70%), limited funds (61%), uninformed teachers (58%), and with regard to adults these barriers were uninformed patients (64%), lack of knowledge on ADHD in adults on the part of the GPs (63%), and consultation time (58%). Although GPs did seem to have an awareness of the important role of the psychologist in the diagnosis and effective management of patients with ADHD, their referral practices generally involved a limited interdisciplinary approach. Conclusion: It is recommended that the limited knowledge base of GPs with regard to ADHD should be addressed by adapting the curriculum of undergraduate medical students and providing opportunities for continued medical education that focuses on the diagnosis and management of ADHD, in both children and adults. GPs should acknowledge the educational psychologist as an equal partner within a multidisciplinary team.

Objective To explore the characteristics of resting-state functional connectivity in male adults with attention deficit hyperactivity disorder (ADHD) and the relationship with clinical symptoms. Method Forty-seven male adult ADHD patients diagnosed by DSM-Ⅳ-TR and 47 healthy controls matched with sex, age and IQ were enrolled by clinical interviews. All subjects underwent structural MRI scan and resting-state functional MRI scan. All subjects were rated the ADHD symptom severity with the ADHD symptom rating scale. A two independent-samples t-test was used to analyze the differences of the resting-state functional connectivity strength (FCS) between the male adult ADHD group and the healthy control group. Results Compared with healthy controls, adult ADHD patients had shown the reduced FCS in the right middle temporal gyrus(t=-3.42), inferior temporal gyrus (t=-3.32), right middle occipital gyrus (t=-3.11) and inferior occipital gyrus (t=-4.44,P<0.05 after multiple correction). The FCS of right inferior occipital gyrus in ADHD group had a tendency to negatively correlated with the severity of symptoms (r=-0.403, P<0.05). A trend of negative correlation between the FCS in the right inferior occipital gyrus in ADHD group and the attention deficit score was found (r=-0.507, P<0.05). Conclusion Abnormalities in resting-state brain function connectivity are prominent in male adult ADHD patients. Occipitallobe dysfunction may be more related to the severity of the ADHD symptoms. Temporal lobe and occipital lobe seem to be crucial to the pathogenesis of adult male ADHD. Key words: Attention deficit disorder with hyperactivity; Magnetic resonance imaging; Adult; Functional connectivity

Evaluation of common variants in 16 genes involved in the regulation of neurotransmitter release in ADHD

Objective: Attention deficit hyperactivity disorder (ADHD) is a neuropsychiatric illness and etiopathogenetic studies focus on fronto-striatal circuit. Soft neurologic signs that are used in the investigation of brain function disorders in psychiatric diseases were studied more in childhood ADHD. In the present study, it is aimed to study the neuropsychologic test performances that are sensitive to frontal lobe functions and soft neurologic signs in adult ADHD. Methods: Sixty subjects with ADHD and 60 healthy control subjects aging between 18-60 years were included into the study. Presence of comorbid psychiatric disorder was not investigated in the ADHD group. Neurological examination for soft signs and neuropsychologic tests (Digit span, verbal memory, Stroop task and Wisconsin card sorting test (WCST)) were performed to both groups. Neurological examination for soft signs and neuropsychologic tests of 59 patients and 46 control subjects were regarded as effective and were analyzed statistically. Results: Mean age was 28.93±8.08 years in the ADHD group (59.3% female, 40.7% male) and 32.07±8.11 years in the control group (63.0% female, 37.0% male). Significantly low performance was determined in digit span, verbal memory and Stroop task tests in adult ADHD group according to the control group. No difference was determined in WCST between adult ADHD and control groups. In the neurological examination for soft signs, adult ADHD group had significantly low performance according to the control group in motor coordination and finger-thumb opposition tests. Adult ADHD group had significantly low performance according to the control group in sensory integration and audiovisual integration and extinction tests. Adult ADHD group had low performance according to the control group in memory, synkinesis and gaze impersistence tests in “Others tests”. Discussion: It is implied that ADHD is common in childhood and its symptoms decrease in adulthood. It is also thought that a functional defect continues in frontal lobe, cerebellum, parietal lobe and/or in fronto-striatal pathways that provide associations between each other and this may affect the prognosis and treatment of the disorder.

Back to table of contents Previous article Next article LetterFull AccessADHD in Adult Psychiatric OutpatientsBen Lomas, M.D., and Peter Gartside, M.S., Ph.D.Ben LomasSearch for more papers by this author, M.D., and Peter GartsideSearch for more papers by this author, M.S., Ph.D.Published Online:1 May 1999https://doi.org/10.1176/ps.50.5.705AboutSectionsView EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail To the Editor: Anxiety and depression are two of the most common complaints of psychiatric outpatients, and anxiety and mood disorders are among the most common psychiatric disorders in the United States (1). These disorders are also frequently associated with attention-deficit hyperactivity disorder (ADHD) in both children and adults (2).ADHD is a chronic psychiatric disorder characterized by early childhood onset of motor overactivity (hyperactivity), distractibility (inattentiveness), and impulsivity that often persists into adulthood (3). ADHD affects 3 to 5 percent of all classroom children, and clinically significant signs and symptoms of ADHD may persist into adulthood in 60 to 70 percent of the cases. Therefore, one would expect to find a disproportionately large number of psychiatric patients with ADHD.This report describes a study that attempted to measure the frequency of ADHD in a cross-sectional sample of 212 randomly assigned adult psychiatric outpatients, none of whom were referred for or were being treated for ADHD. The sample consisted of 130 veterans being treated in a Veterans Affairs mental hygiene clinic, 42 outpatients at a community mental health center, and 40 consecutive private psychiatric outpatients first seen by the first author in 1993 and followed for 24 to 36 months.Of the 212 outpatients, only 114, or 54 percent, received a complete ADHD assessment. Ninety-eight patients (46 percent) were excluded because of psychosis or evidence of structural brain damage. The average age of the 114 patients was 43 years, 68 percent were male, and 97 percent were Caucasian. Sixty-one percent were married, and 21 percent were divorced. Fifty-one percent were employed; the remainder were partly or total disabled or retired.Formal ADHD evaluation consisted of a review of family and childhood history and a review of grade-school report cards and school records whenever possible. Patients were also evaluated by DSM-III-R criteria for ADHD. They were scored on the Wender Utah Rating Scale (WURS) and Wender's suggested 25 items (WURS-25), which measure recollected early grade school problems (4), and on Hallowell and Ratey's 20-item Suggested Adult ADHD Criteria (5). The first author interviewed significant others and first-degree relatives using Wender's ten-item Parental Rating Scale (WPRS), which measures observations of motor overactivity, distractibility, and impulsivity, or relied on professional staff's observations.To receive a diagnosis of ADHD, a subject had to meet eight or more of the DSM-III-R criteria and have a score of 46 or more on the WURS-25, 12 or more on the Hallowell-Ratey criteria, or 10 or more on the WPRS. The subject also had to be found positive for ADHD by clinical observation, by observation of a significant other, or according to childhood school records.Fifty-seven of the 114 patients, or 50 percent, received a diagnosis of ADHD. Patients who were diagnosed with ADHD met a mean±SD of 10.3±2.5 DSM-III-R criteria. WPRS scores were obtained for 40 patients; the mean score was 15.9±3.8. The mean score on the Hallowell-Ratey scale was 17.2±1.6; on the WURS-25 it was 58.9±14.1; and on the WURS it was 113.8±28.3. Childhood school records indicated ADHD in 27 of 30 cases in which records were available.Seventeen cases of panic disorder were found in the ADHD group, but only four cases in the group without ADHD. A total of 29 cases of anxiety disorder were found in the ADHD group, compared with 11 in the other group.Fifteen of the 18 outpatients, or 83 percent, who were assessed from the community mental health center received a diagnosis of ADHD. This disproportionately high figure might be related to a higher incidence of poverty among these patients, but further study is needed.This preliminary study of ADHD in adults relied primarily on clinical observations over comparatively long time periods, ranging from 24 to 36 months. Future studies will require separating the processes of diagnosis, ADHD assessment, and treatment into controlled segments for the sake of believability and accuracy. However, the fact that the patients in the study were observed over a substantial period increases the likelihood that they did in fact have ADHD.Dr. Lomas is a staff psychiatrist at the Veterans Affairs Medical Center in Cincinnati and associate professor of psychiatry at the University of Cincinnati Medical Center. Dr. Gartside is associate professor of biostatistics and epidemiology in the department of enviromental health at the University of Cincinnati College of Medicine.

Background:Studies investigating sensory processing in attention-deficit/hyperactivity disorder (ADHD) have shown altered visual and auditory processing. However, evidence is lacking for audiovisual interplay — namely, multisensory integration. As well, neuronal dysregulation at rest (e.g., aberrant within- or between-network functional connectivity) may account for difficulties with integration across the senses in ADHD. We investigated whether sensory processing was altered at the multimodal level in adult ADHD and included resting-state functional connectivity to illustrate a possible overlap between deficient network connectivity and the ability to integrate stimuli.Methods:We tested 25 patients with ADHD and 24 healthy controls using 2 illusionary paradigms: the sound-induced flash illusion and the McGurk illusion. We applied the Mann–Whitney U test to assess statistical differences between groups. We acquired resting-state functional MRIs on a 3.0 T Siemens magnetic resonance scanner, using a highly accelerated 3-dimensional echo planar imaging sequence.Results:For the sound-induced flash illusion, susceptibility and reaction time were not different between the 2 groups. For the McGurk illusion, susceptibility was significantly lower for patients with ADHD, and reaction times were significantly longer. At a neuronal level, resting-state functional connectivity in the ADHD group was more highly regulated in polymodal regions that play a role in binding unimodal sensory inputs from different modalities and enabling sensory-to-cognition integration.Limitations:We did not explicitly screen for autism spectrum disorder, which has high rates of comorbidity with ADHD and also involves impairments in multisensory integration. Although the patients were carefully screened by our outpatient department, we could not rule out the possibility of autism spectrum disorder in some participants.Conclusion:Unimodal hypersensitivity seems to have no influence on the integration of basal stimuli, but it might have negative consequences for the multisensory integration of complex stimuli. This finding was supported by observations of higher resting-state functional connectivity between unimodal sensory areas and polymodal multisensory integration convergence zones for complex stimuli.

Attention deficit hyperactivity disorder (ADHD) is a common and highly heritable psychiatric disorder in children and adults. Recent meta-analyses have indicated an association between genes involved in dopaminergic signaling and childhood ADHD, but little is known about their possible role in adult ADHD. In this study of adults with ADHD, we evaluated the three most commonly studied ADHD candidate genetic polymorphisms; the dopamine receptor D4 (DRD4) exon 3 VNTR repeat, a microsatellite repeat 18.5 kb upstream of the DRD5 locus and the 3'UTR dopamine transporter SLC6A3 (DAT 1) VNTR. We examined 358 clinically diagnosed adult Norwegian ADHD patients (51% males) and 340 ethnically matched controls. We found a nominally significant overall association with adult ADHD for the DRD5 microsatellite marker (P = 0.04), and a trend toward increased risk associated with the 148-bp allele consistent with recent meta-analyses. The strongest overall association (P = 0.02) and increased risk for the 148-bp allele [odds ratio (OR) = 1.27 (95% CI: 1.00-1.61)] were seen in the inattentive and combined inattentive/hyperactive group as previously reported for childhood ADHD. No association was found for the DRD4 or SLC6A3 polymorphisms in this patient sample. In conclusion, our results among adults with a clinical diagnosis of ADHD support an association between ADHD and the DRD5 locus, but not the DRD4 or SLC6A3 loci. It is possible that the latter polymorphisms are associated with a transient form of ADHD with better long-term clinical outcome.

Adult Attention Deficit Hyperactivity Disorder: Moving Beyond DSM-IV

The dopamine transporter haplotype and reward-related striatal responses in adult ADHD

BackgroundAttention Deficit Hyperactivity Disorder (ADHD) is a common neurodevelopmental disorder characterised by the symptoms of inattention, impulsivity and hyperactivity. ADHD was once perceived as a condition of childhood only; however increasing evidence has highlighted the existence of ADHD in older adolescents and adults. Estimates for the prevalence of ADHD in adults range from 2.5–4%. Few data exist on the prescribing trends of the stimulants methylphenidate and dexamfetamine, and the non-stimulant atomoxetine in the UK. The aim of this study was to investigate the annual prevalence and incidence of pharmacologically treated ADHD in children, adolescents and adults in UK primary care.MethodsThe Health Improvement Network (THIN) database was used to identify all patients aged over 6 years with a diagnosis of ADHD/hyperkinetic disorder and a prescription for methylphenidate, dexamfetamine or atomoxetine from 2003–2008. Annual prevalence and incidence of pharmacologically treated ADHD were calculated by age category and sex.ResultsThe source population comprised 3,529,615 patients (48.9% male). A total of 118,929 prescriptions were recorded for the 4,530 patients in the pharmacologically treated ADHD cohort during the 6-year study. Prevalence (per 1000 persons in the mid-year THIN population) increased within each age category from 2003 to 2008 [6–12 years: from 4.8 (95% CI: 4.5–5.1) to 9.2 (95% CI: 8.8–9.6); 13–17 years: from 3.6 (95% CI: 3.3–3.9) to 7.4 (95% CI: 7.0–7.8); 18–24 years: from 0.3 (95% CI: 0.2–0.3) to 1.1 (95% CI: 1.0–1.3); 25–45 years: from 0.02 (95% CI: 0.01–0.03) to 0.08 (95% CI: 0.06–0.10); >45 years: from 0.01 (95% CI: 0.00–0.01) to 0.02 (95% CI: 0.01–0.03). Whilst male patients aged 6-12 years had the highest prevalence; the relative increase in prescribing was higher amongst female patients of the same age - the increase in prevalence in females aged 6–12 years was 2.1 fold compared to an increase of 1.9 fold for their male counterparts. Prevalence of treated ADHD decreased with increasing age. Incidence (per 1000 persons at risk in the mid-year THIN population) was highest for children aged 6–12 years.ConclusionsA trend of increasing prescribing prevalence of ADHD drug treatment was observed over the period 2003–2008. Prevalence of prescribing to adult patients increased; however the numbers treated are much lower than published estimates of the prevalence of ADHD. This study has added to the limited knowledge on ADHD prescribing in primary care, particularly in the area of drug treatment in adulthood.

Attention‐deficit hyperactivity disorder in a life perspective

BackgroundThe prevalence of attention deficit hyperactivity disorder (ADHD) in adult obsessive-compulsive disorder (OCD) patients has been reported to range from 5.5% to 52%. Conversely, adult ADHD patients are often associated with a variety of comorbidities including OCD. The reported prevalence of comorbidity of OCD in adult ADHD patients had varied widely in previous studies, ranging from 3%–44%. These findings regarding comorbidity indicate a bilateral linkage between OCD and ADHD, suggesting the possible existence of common biological bases for the development of the disorders.On the other hand, ADHD is considered as a complex disorder with clinical and genetic heterogeneity and elevated heritability, and childhood ADHD symptoms fulfilling diagnostic criteria often improve with age. Thus, it is clinically meaningful and useful to regard the continuous nature of ADHD psychopathology as widely variable, ranging from a diagnostic entity to a trait with subthreshold ADHD conditions in general and clinical populations. Indeed, it can be assumed that there may be a population of OCD patients with ADHD traits, even if they do not meet the diagnostic threshold for ADHD.AimsIn this study, we sought to clarify the subthreshold characteristics of ADHD examining validity or clinical utility of the ADHD-trait group defined by the ADHD index score on CAARS in the OCD population.MethodsWe assessed lifetime comorbidity of ADHD using a structured diagnostic interview on the basis of DSM-5 diagnostic criteria in 87 adult Japanese patients with OCD. Additionally, we used the Japanese version of Conners’ Adult ADHD Rating Scales to assess the characteristics and severity of ADHD in each participant. According to the results, we divided these subjects into 3 groups; OCD subjects in the ADHD+ group were determined as having comorbid ADHD during their lifetime, along with the ADHD index score >65 at the initial assessments. the ADHD-trait group was assigned by the finding that they did not have lifetime ADHD but who exceeded the threshold of the ADHD index, and others that exhibited the ADHD index below the threshold score were included in the non-ADHD group (ADHD− group). We compared these groups in terms of background profiles and clinical features, such as OCD symptomatology and psychometric test results. Additionally, the 6-month treatment outcome was compared prospectively between the groups.ResultsIn the ADHD trait group (N=23), in addition to each subscale score on the CAARS distributed between the ADHD+ (N=14) and ADHD- (N=50) groups. the clinical features such as a higher impulsivity, a lower level of functioning, and increased prevalence of substance and/or behavioral addictions. were comparable to those in the ADHD+ group or in between those in the ADHD+ group and the ADHD- group, Moreover, the subjects in the ADHD+ group were significantly less responsive to the 6-month standard OCD treatments than those in the OCD- group, and the ADHD trait group showed intermediate responsivity.DiscussionThese results suggested the existence of possible continuous nature of ADHD pathology among the OCD patients, and also supported clinical utility and some validity of this group classification.