Differentiation of ADHD and Depression Based on Cognitive Performance

Abstract

Objective: The aim of this study was to assess whether self-report scales and neuropsychological tests used for adult patients with ADHD can help to distinguish between ADHD-specific and depressive symptoms. Method: In a cross-sectional design, differences in self-report questionnaires and neuropsychological tests among clinical subgroups and healthy controls (HC) were evaluated. Patients in clinical groups were diagnosed with major depressive disorder (MDD) or ADHD with or without depressive symptoms according to Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) guidelines. Results: The Hyperactivity subscales of the Conners’ Adult ADHD Rating Scale (CAARS) differed between MDD and ADHD, whereas self-concept and inattention scales even distinguished comorbidity subgroups within the ADHD population. A reduced alertness and higher variations in reaction times measured by performance tests indicated problems in sustained attention in ADHD patients compared with HC. Conclusion: The diagnostic process of ADHD, and thereby the distinction from other symptom-overlapping, comorbid mental disorders, might be improved by utilizing ADHD-specific self-report questionnaires and neuropsychological tests, which are short, cost-effective, and standardized screening methods.

Cognitive characterization of adult attention deficit hyperactivity disorder by domains: a systematic review

“…Mehren et al (2019) showed that reaction time variability, significantly more pronounced in ADHD patients, could decrease with exercise. Sustained attention deficits as compared to controls were also reported by Weyandt et al (2013), as represented by the CPT II Standard Error of reaction time (Cohen's d = 0.798), as well as by Grane et al (2014) on the TOVA test; by Holst and Thorell (2017) on a Navon like task (ANCOVA = 0.53); by Maruta et al (2017) when measuring visual tracking performance with the Attention Network Test and Spatial Span of the WMS-III, and by Paucke et al (2019), with reduced alertness and higher variations in reaction times measured by the TAP test. More recently, Lin and Gua (2020), who went further by detailing specific differences for early-onset and late-onset ADHD participants when compared to healthy controls, showed that only early-onset individuals showed significant impairment in the CANTAB probability of hit (sustained attention) in a second model of multiple analysis, while initially both early and late onset groups had showed impairment.…”

The Role of Self- and Informant-Reports on Symptoms and Impairments in the Clinical Evaluation of Adult ADHD

“…Comparing individuals with ADHD to the group of individuals showing indications of other psychiatric disorders (CCG), fewer differences were observed, i.e., the ADHD group reported higher scores on their current (ADHD-SR; CAARS) and retrospective (WURS-K) ADHD symptoms but lower scores on depression (BDI). Hence, also in differentiation to patients having other psychiatric disorders, ADHD symptomatology seems to have a key role and appears to have clinical value [38,40,42]. Considering the fact that the majority of individuals in the CCG showed indications of mood disorders (37 of 53), higher depression scores appear logical and may serve as useful information to differentiate ADHD from depressive disorders.…”

“…Yet, the WURS was found to be of only limited value to differentiate between ADHD and the other psychological disorders in a further study of the same group, which revealed a high rate of false positives (16%) in individuals who either were diagnosed with other psychological disorders or reported depressive symptoms [38,39]. In contrast, in a more recent study, Paucke and colleagues highlighted the utility of both the WURS and some subscales of the CAARS in the differentiation of ADHD and major depressive disorder [40]. Further, McCann and Roy-Byrne examined the utility of a number of ADHD self-report scales for the diagnostic screening of adults referred for an ADHD evaluation.…”

“…Given this well-documented overlap, it can be assumed that scales focusing on ADHD symptoms are not adequate instruments to serve the purpose of differential diagnosis but that measures for other clinical conditions with which ADHD is commonly confused may be more promising. In this context, Paucke and colleagues reported a large-sized difference between adults with ADHD and adults with major depressive disorder in self-reported symptoms of depression, as assessed with the Beck Depression Inventory-II (BDI-II) [40]. However, this effect was not found in an earlier study comparing patients with ADHD and bipolar disorder [47].…”

The role of comorbid depressive symptoms on long-range temporal correlations in resting EEG in adults with ADHD

“…Comorbid depression therefore presents important clinical challenges [12,13] since its co-occurrence leads to greater illness burden and complexity than those individuals with aADHD or depression alone [11]. On the other hand, there is growing evidence from neuropsychological and electrophysiological studies that suggests no significant difference in cognitive performance [14] or in absolute power in specific frequency band measuring by electroencephalography (EEG) between depressed and non-depressed aADHD [15][16][17][18]. These results may question the usefulness and reliability of objective markers in differentiating between ADHD and depressive symptoms in adults.…”