Diagnostic delay in ADHD: Duration of untreated illness and its socio-demographic and clinical predictors in a sample of adult outpatients

Waiting Times and Influencing Factors in Children and Adults Undergoing Assessment for Autism, ADHD, and Other Neurodevelopmental Differences

This study explored waiting times and the factors influencing them in child and adult populations undergoing assessment for autism, ADHD, and other neurodevelopmental differences. The analysis focused on a retrospective review of 408 cases with assessments completed between October 2021 and May 2022, conducted by 30 diagnosing teams in Scotland. Data included age, final diagnosis, demographics, medical and developmental history, contact frequency, and assessment service adherence to best-practice standards. Waiting times were calculated, and relationships were analyzed using linear regression. Median waiting times were 525 days (IQR 329-857) for children/adolescents and 252 days (IQR 106-611) for adults. Only 20% of children's and 47% of adult assessments met the proposed 252-day diagnostic time target. Autism and ADHD were the most common diagnoses. Receiving > 1 neurodevelopmental diagnosis on completion was uncommon. Demographic factors did not significantly affect waiting times. Children/adolescents with more complex developmental and medical histories experienced longer waits (100.3 weeks vs. 67.7 weeks; p < 0.001), while adults with similar histories had shorter waits (32.7 weeks vs. 57.4 weeks; p = 0.016). Adults with ADHD experienced longer waits than autistic adults (63.4 weeks vs. 38.6 weeks, p = 0.002). Adherence to best-practice quality standards was associated with shorter waits for children (β = 0.27, p = 0.002), but the relationship between standard adherence at different stages and for adults was less clear. More frequent appointments correlated with shorter adult waits (33.7 weeks vs. 59.2 weeks, p = 0.015). Gender distribution was balanced among adults, but children's services included more boys. The study highlights long waits and the need for improvement in processes.

Could Maladaptive Daydreaming Delay ADHD Diagnosis Until Adulthood? Clinical Characteristics of Adults With ADHD Based on Diagnosis Age

INTRODUCTION

Our study aimed to compare the sociodemographic, diagnostic, clinical, and self-report scale data of adults diagnosed with ADHD in childhood/adolescence versus adulthood and to identify risk factors associated with delayed/missed diagnosis for ADHD.

METHOD

Sociodemographic, clinical, and diagnostic data of 214 adults with ADHD, followed at the Adult Neurodevelopmental Disorders Clinic, Selçuk University, between January 2022 and January 2024, were analyzed. The diagnostic evaluations were made using the Structured Clinical Interview for DSM-5 Clinician Version. Clinical data included age, gender, years of education, alcohol/substance use, diagnosis age, and current medication use for ADHD. Data collected from self-report scales included both ADHD-related measurements and comorbidity-related measurements.

RESULTS

The findings revealed that only 34.4% (n = 74) of sample received a formal ADHD diagnosis during childhood/adolescence. Adults diagnosed with ADHD in adulthood were older and had higher education levels, more severe ADHD symptoms, and increased maladaptive daydreaming (MD) scores, compared to those diagnosed in childhood or adolescence. Logistic regression analysis indicated that the severity of MD was associated with being in the group diagnosed with ADHD in adulthood while controlling for other significant parameters from bivariate analyses, such as age, years of education, and current medication use for ADHD. Finally, analyses conducted separately in both groups showed that: (1) increased MD severity was a predictor of higher ADHD symptoms in those diagnosed in adulthood, but not in those diagnosed in childhood/adolescence, and (2) MD severity had a stronger correlation with ADHD symptoms, the number of comorbid psychiatric disorders, and symptoms of excessive mind wandering, depression, and anxiety in those diagnosed in adulthood compared to those diagnosed in childhood/adolescence.

CONCLUSION

MD may delay ADHD diagnosis until adulthood by masking and compensating ADHD symptoms and delay in referral to mental health professionals, and it might also be a predictive symptom for recognizing ADHD in adults who have never been diagnosed; however, longitudinal studies are needed to confirm this.

Interpretable machine learning approaches for children's ADHD detection using clinical assessment data: an online web application deployment

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is a prevalent mental disorder characterized by hyperactivity, impulsivity, and inattention. This study aims to develop a verifiable and interpretable machine learning model to identify ADHD and its subtypes in children using clinical assessment scales data.

METHODS

This study utilized the ADHD-200 dataset, including demographic data, Behavioral Rating Scale, and Wechsler Intelligence Scale assessments, to train and validate our models. The model's performance was evaluated using 10-fold cross-validation within the internal dataset, and the best model will be used for external validation. Seven machine learning models were evaluated. The SHapley Additive exPlanations (SHAP) method was employed for model interpretation. Finally, a web application will deploy the prediction model to provide ADHD probabilities based on user input.

RESULTS

The Random Forest (RF) model performing best in identifying ADHD and the Support Vector Machine (SVM) model excelling in distinguishing ADHD subtypes. The RF model achieved an AUC of 0.99 in 10-fold cross-validation and an AUC of 0.99 in external validation, and the SVM model achieved a micro-average AUC of 0.96 and an accuracy of 0.83 in internal validation and a micro-average AUC of 0.96 and an accuracy of 0.85 in external validation. We used SHAP to interpret the models, revealing that higher ADHD Index pushed the model towards ADHD classification. Additionally, lower IQ scores were correlated with a higher likelihood of ADHD, consistent with previous studies. The dependency analysis found that the model can identify different behavioral scales. We deployed the final model online using a web application and showed users how the model made decisions.

CONCLUSIONS

Our findings highlight the potential of using machine learning and clinical assessment scales to support the diagnosis and subtype identification of ADHD in children, offering a practical solution for improving diagnostic accuracy and efficiency in clinical settings.

Identifying reversible psychiatric dementia mimics in new memory clinic outpatients

Background

Timely identification of reversible conditions that mimic dementia is critical in memory clinic practice. However, psychiatric conditions as potential dementia mimics have not been studied as thoroughly as neurological ones, and detailed data on their reversibility remain limited.

Objective

To identify reversible psychiatric dementia mimics.

Methods

A retrospective chart review was conducted on 749 new outpatients to investigate etiologies, progression rates, a neuropsychological assessment, cognitive and functional levels, and potential reversibility, categorized by psychiatric and neurological conditions. Cases showing cognitive reversibility following treatment were also identified. Comparisons were made based on the presence or absence of potential reversibility, as well as actual reversibility.

Results

Among the 749 individuals, 121 (16.2%) had potentially reversible conditions: 75 psychiatric and 46 neurological. Psychiatric conditions included depression, schizophrenia and delusional disorders, developmental disorders, alcohol use disorder, and dissociative and anxiety disorders. Compared to individuals without potentially reversible conditions, individuals with psychiatric conditions were younger, had a faster progression rate, and demonstrated higher cognitive function. Of the individuals who had mild cognitive impairment or dementia mimic, 6 (0.9%) showed complete cognitive resolution (3 cases) or partial cognitive improvement (3 cases). These 6 cases included two individuals with psychiatric conditions manifesting psychotic features.

Conclusions

While rare, reversible psychiatric dementia mimics highlight the importance of comprehensive evaluations in memory clinics, particularly for younger individuals experiencing rapid cognitive decline. The infrequency of reversibility may reflect a strong association between these potentially reversible conditions and dementia risk factors, or their role as prodromes of dementia itself.

Cognitive strengths in neurodevelopmental disorders, conditions and differences: A critical review

Neurodevelopmental disorders are traditionally characterised by a range of associated cognitive impairments in, for example, sensory processing, facial recognition, visual imagery, attention, and coordination. In this critical review, we propose a major reframing, highlighting the variety of unique cognitive strengths that people with neurodevelopmental differences can exhibit. These include enhanced visual perception, strong spatial, auditory, and semantic memory, superior empathy and theory of mind, along with higher levels of divergent thinking. Whilst we acknowledge the heterogeneity of cognitive profiles in neurodevelopmental conditions, we present a more encouraging and affirmative perspective of these groups, contrasting with the predominant, deficit-based position prevalent throughout both cognitive and neuropsychological research. In addition, we provide a theoretical basis and rationale for these cognitive strengths, arguing for the critical role of hereditability, behavioural adaptation, neuronal-recycling, and we draw on psychopharmacological and social explanations. We present a table of potential strengths across conditions and invite researchers to systematically investigate these in their future work. This should help reduce the stigma around neurodiversity, instead promoting greater social inclusion and significant societal benefits.

Review of Studies on Incremental Validity of Assessment Measures Used in Psychological Assessment of Attention-Deficit Hyperactivity Disorder

Few studies have summarized the literature relevant to the incremental validity of tools and procedures for the assessment of attention-deficit hyperactivity disorder (ADHD). The current project reviewed such studies published in the prior 18 years. Results from studies on the incremental validity of measures used in the assessment of ADHD were reviewed. Measures included symptom reports, clinical interviews, behavioral observation, continuous performance and other psychomotor tasks, intelligence tests, and measures of executive function. Twenty-nine published studies and two reviews were identified from 2004 to 2022. Incremental validity was determined using various statistics including R2, classification metrics, odds ratios, and post-test probabilities. Findings suggest that symptom reports from a collateral source and continuous performance test measures have incremental validity over self-reports and clinical interviews. Measures of intellectual and executive functioning did not show incremental validity in the diagnosis of ADHD. Findings are relevant to the practitioner, as they bear on the optimization of both the cost-effectiveness and the diagnostic accuracy of combined procedures in the assessment of ADHD.

Potential Mechanisms Underlying Suicidality in Autistic People with Attention Deficit/Hyperactivity Disorder: Testing Hypotheses from the Interpersonal Theory of Suicide

Background

Autistic people with co-occurring attention deficit/hyperactivity disorder (ADHD) appear to be at heightened risk of suicide. To understand why, we explored two explanatory mechanisms from the interpersonal theory of suicide: first, that co-occurring ADHD might be associated with greater risk through greater thwarted belongingness and perceived burdensomeness and, secondly, that hyperactive/impulsive features might incur additional risk through their association with painful and provocative events, which are suggested to create "capability" for suicide.

Methods

Autistic adults (n = 314) completed an online survey including measures of thwarted belongingness, perceived burdensomeness, painful and provocative events, acquired capability for suicide, and ADHD features. Creating an overall index of likely ADHD, we examined associations between likely ADHD, suicide ideation, and lifetime suicide attempts through the parallel mediators of thwarted belongingness, perceived burdensomeness, anxiety, and depression. In several models, we then examined hyperactive, impulsive, and inattentive features as predictors of exposure to painful and provocative events and subsequent capability for suicide, and examined whether these two variables, sequentially or individually, mediated an association with lifetime suicide attempts.

Results

Likely ADHD was associated with past-year suicide ideation through greater depression and perceived burdensomeness, which also mediated its association with more suicide attempts. Hyperactive and impulsive features were associated with exposure to painful and provocative events and through this acquired suicide capability. Both features were associated with more numerous suicide attempts through these two mediators sequentially, and through exposure to painful and provocative events alone.

Conclusions

These data suggest that suicidality in autistic people with ADHD may be partially related to perceived burdensomeness and to acquired suicide capability after exposure to painful and provocative events. However, as we observed a pathway to suicidality associated with painful and provocative events alone, it is likely that there are also other explanatory mechanisms for the influence of traumatic events on suicide risk.

"Dysregulated not deficit": A qualitative study on symptomatology of ADHD in young adults

OBJECTIVE

Attention-deficit/hyperactivity disorder (ADHD) is a common condition that often persists into adulthood, although data suggest that the current diagnostic criteria may not represent how the condition presents in adults. We aimed to use qualitative methods to better understand ADHD symptomatology in young adults, especially regarding attentional and emotional dysregulation.

METHODS

Nine focus groups involving young adults (aged 18-35 years; N = 43; 84% female; 86% US and Canada) with diagnoses of ADHD were conducted. Participants were asked about their perceptions of the current diagnostic criteria and how their symptoms have presented and changed over time. Data were analyzed using an interpretive phenomenological analysis framework.

RESULTS

Most participants reported that the diagnostic criteria did not accurately capture their experiences with ADHD. They reported struggling with attention dysregulation, including hyperfocusing, and emotional dysregulation, including rejection-sensitive dysphoria. Many participants believed that their changing environments and behavioral adaptations influenced how their symptoms presented into adulthood.

CONCLUSION

Current diagnostic criteria for ADHD may not capture the range of symptoms present in young adults. More research is needed to characterize attentional and emotional dysregulation in this population.

Effectiveness of cognitive behavioural-based interventions for adults with attention-deficit/hyperactivity disorder extends beyond core symptoms: A meta-analysis of randomized controlled trials

OBJECTIVES

To provide an updated systematic review of randomized controlled studies for the efficacy of cognitive behavioural therapy (CBT) in treating adults with attention-deficit/hyperactivity disorder (ADHD).

DESIGN

Meta-analysis.

METHODS

PROSPERO registration: CRD42021273633. The methods used aligned with the PRISMA guidelines. Database searches identified CBT treatment outcome studies eligible for conducted meta-analysis. Treatment response was summarized by calculating the standardized mean differences for changes in outcome measures for adults with ADHD. Measures included core and internalizing symptoms and were assessed on the basis of self-reporting and investigator evaluation.

RESULTS

Twenty-eight studies met the inclusion criteria. This meta-analysis indicates that CBT for adults with ADHD was effective in reducing both core and emotional symptoms. Decreases in depression and anxiety were predicted by the reduction of core ADHD symptoms. An increase in self-esteem and quality of life were also observed for adults with ADHD who were received CBT. Adults who received either individual or group therapy significantly exhibited a greater reduction of symptoms than those who received active control intervention, received treatment as usual, or were on the treatment waitlist. Traditional CBT was equally effective in reducing core ADHD symptoms but outperformed other CBT approaches in reducing emotional symptoms among adults with ADHD.

CONCLUSIONS

This meta-analysis offers cautiously optimistic support for the efficacy of CBT in treating adults with ADHD. The additional reduction of emotional symptoms demonstrates the potential of CBT in adults with ADHD who are at higher risk for depression and anxiety comorbidities.

History of Childhood/Adolescence Referral to Speciality Care or Treatment in Adult Patients with Attention-Deficit/Hyperactivity Disorder: Mutual Relations with Clinical Presentation, Psychiatric Comorbidity and Emotional Dysregulation

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental condition that only rarely remits in adulthood. While several studies underlined differences between child and adult ADHD, the relationship between adult clinical presentation and early referral/treatment has been rarely investigated. In our study, 100 adults with ADHD were recruited and subdivided according to a history of referral to speciality care or treatment with methylphenidate (MPH) during childhood/adolescence. The early referral was associated with a history of disruptive behaviors during childhood/adolescence. Current ADHD symptoms were more pronounced in patients first referred during childhood/adolescence but never treated with MPH. Early MPH treatment was associated with lower rates of mood disorders and lower severity of emotional dysregulation at the time of assessment. Negative emotionality mediated the relationship between MPH treatment and mood disorders comorbidity. ADHD patients first referred during childhood/adolescence are characterized by more externalizing features than those first referred in adulthood. MPH treatment during the developmental age may have a role in preventing mood disorders in patients with ADHD, possibly by reducing emotional dysregulation.

Screening for Adulthood ADHD and Comorbidities in a Tertiary Mental Health Center Using EarlyDetect: A Machine Learning-Based Pilot Study

Screening for adult Attention-Deficit/Hyperactivity Disorder (ADHD) and differentiating ADHD from comorbid mental health disorders remains to be clinically challenging. A screening tool for ADHD and comorbid mental health disorders is essential, as most adult ADHD is comorbid with several mental health disorders. The current pilot study enrolled 955 consecutive patients attending a tertiary mental health center in Canada and who completed EarlyDetect assessment, with 45.2% of patients diagnosed with ADHD. The best ADHD classification model using composite scoring achieved a balanced accuracy of 0.788, showing a 2.1% increase compared to standalone ADHD screening, detecting four more patients with ADHD per 100 patients. The classification model including ADHD with comorbidity was also successful (balanced accuracy = 0.712). The results suggest the novel screening method can improve ADHD detection accuracy and inform the risk of ADHD with comorbidity, and may further inform specific comorbidity including MDD and BD.

Prevalence of Metabolic Syndrome and Insulin Resistance in a Sample of Adult ADHD Outpatients

BACKGROUND

High prevalence of Metabolic Syndrome (MS) was found in patients with schizophrenia and bipolar disorders. Insulin Resistance (IR) seems to mediate MS role in developing cardiometabolic consequences.

AIMS

To investigate the prevalence of MS, and the role of MS components and IR surrogate indexes in determining MS in adult ADHD outpatients.

METHODS

In the present cross-sectional study, MS, defined according to the Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults (ATP III), and IR surrogate indexes were assessed on a consecutive sample of adult ADHD outpatients. Logistic regression analysis was performed to evaluate the effect of each ATP III component and IR surrogate index in determining MS.

RESULTS

Seventeen out of 158 patients (10.8%, 95%CI = 0.064/0.167) fulfilled the ATP-III criteria for MS. A comprehensive comparison with prevalence in the reference population was hindered by the lack of patients over 60 in the study sample, however under this age no significant differences were found. Among MS components, blood triglycerides level (OR = 1.02, 95%CI=1.01/1.03, p = 0.001) was the main predictor for MS, followed by diastolic blood pressure (OR = 1.08, 95%CI=1.01/1.16, p = 0.024) and waist circumference (OR = 1.06, 95%CI=1.01/1.13, p = 0.029). Lipid Accumulation Product (LAP, OR = 1.0006, 95%CI=1.0003/1.0009, p < 0.001) outperformed Triglyceride-Waist Circumference (TG-WC, OR=1.03, 95%CI=1.01/1.04, p < 0.001) in predicting MS.

CONCLUSIONS

More attention should be paid not only to MS but also to each ATP III component of MS and LAP in ADHD patients both at first assessment and during follow-up process.

Economic burden of attention-deficit/hyperactivity disorder among adults in the United States: a societal perspective

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is associated with substantial clinical burden as individuals transition to adulthood, including higher rates of comorbidities, mortality, incarceration, and psychiatric hospitalizations than in individuals without ADHD. These higher rates likely contribute to substantial economic burden as well. OBJECTIVE: To provide a comprehensive evaluation of the economic burden associated with ADHD in the US adult population. METHODS: Direct health care costs were obtained by using claims data from the IBM MarketScan Research Databases (January 1, 2017, through December 31, 2018). Direct non-health care costs and indirect costs were estimated on the basis of the literature and government publications. Excess costs incurred by adults with ADHD during 2018 were evaluated from a societal perspective; per-patient costs were extrapolated to the national level. RESULTS: An estimated 8.7 million adults live with ADHD in the United States, resulting in a total societal excess cost attributable to ADHD of $122.8 billion ($14,092 per adult). Excess costs of unemployment ($66.8 billion; 54.4%) comprised the largest proportion of the total, followed by productivity loss ($28.8 billion; 23.4%) and health care services ($14.3 billion; 11.6%). CONCLUSIONS: ADHD in adults is associated with substantial economic burden. DISCLOSURES: This study was funded by Otsuka Pharmaceutical Development & Commercialization, Inc. (Otsuka). The study sponsor contributed to and approved the study design, participated in the interpretation of data, and reviewed and approved the manuscript. Schein is an employee of Otsuka. Gagnon-Sanschagrin, Davidson, Kinkead, Cloutier, Guérin, and Lefebvre are employees of Analysis Group, Inc., a consulting company that provided paid consulting services to Otsuka to develop and conduct this study and write the manuscript. Adler has received research support from Shire/Takeda, Sunovion, and Otsuka; consulting fees from Bracket, Shire/Takeda, Sunovion, Otsuka, the State University of New York (SUNY), the National Football League (NFL), and Major League Baseball (MLB); and royalty payments (as inventor) from New York University (NYU) for license of adult ADHD scales and training materials. Childress has received research support from Allergan, Takeda/Shire, Emalex, Akili, Ironshore, Arbor, Aevi Genomic Medicine, Neos Therapeutics, Otsuka, Pfizer, Purdue, Rhodes, Sunovion, Tris, KemPharm, Supernus, and the US Food and Drug Administration; was on the advisory board of Takeda/Shire, Akili, Arbor, Cingulate, Ironshore, Neos Therapeutics, Otsuka, Pfizer, Purdue, Adlon, Rhodes, Sunovion, Tris, Supernus, and Corium; received consulting fees from Arbor, Ironshore, Neos Therapeutics, Purdue, Rhodes, Sunovion, Tris, KemPharm, Supernus, Corium, Jazz, and Tulex Pharma; received speaker fees from Takeda/Shire, Arbor, Ironshore, Neos Therapeutics, Pfizer, Tris, and Supernus; and received writing support from Takeda/Shire, Arbor, Ironshore, Neos Therapeutics, Pfizer, Purdue, Rhodes, Sunovion, and Tris. Part of the material in this study was presented as a poster at the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) 2021 Virtual Meeting; May 17-20, 2021.

Treatment patterns among adults with attention-deficit/hyperactivity disorder in the United States: a retrospective claims study

OBJECTIVE

To assess treatment patterns in adults with attention-deficit/hyperactivity disorder (ADHD) and associated healthcare costs in a real-world US setting.

METHODS

Claims data from the IBM MarketScan Commercial Subset (Q1/2014-Q4/2018) was used to identify adults diagnosed with ADHD who newly initiated on ADHD treatment (index date). Treatment sequences were defined using an algorithm; for each sequence, the regimen comprised all ADHD-related agents observed within 30 d of the first agent during the 12-month study period. Treatment changes included discontinuation, switch, add-on, and drop. Treatment characteristics were described for the first treatment regimen observed. Total adjusted annual healthcare costs were compared between patients with no treatment change and patients with 1, 2, and ≥3 treatment changes.

RESULTS

Among 122,881 adults with ADHD, the majority initiated a stimulant (95.1%) as their first treatment regimen observed; 9.3% of patients initiated combination therapy of ≥2 ADHD-related agents, and 34.9% of patients had psychotherapy. After an average first treatment regimen duration of 7.1 months, 50.2% of patients experienced a treatment change (22.5% discontinued, 17.5% switched, 5.3% had an add-on, and 4.6% had a treatment drop). Among those who discontinued, 44.8% did so within the first month of initiation. Mean annual healthcare costs were higher among patients with at least 1 treatment change compared to those with no treatment changes; excess costs increased with each additional treatment change.

CONCLUSIONS

Treatment changes were commonly observed and were associated with excess healthcare cost, emphasizing the unmet treatment needs of adults with ADHD in the US.