The Effects of Acute Tryptophan Depletion on Reactive Aggression in Adults with Attention-Deficit/Hyperactivity Disorder (ADHD) and Healthy Controls

Background: The neurotransmitter serotonin (5-HT) has been linked to the underlying neurobiology of aggressive behavior, particularly with evidence from studies in animals and humans. However, the underlying neurobiology of aggression remains unclear in the context of attention-deficit/hyperactivity disorder (ADHD), a disorder known to be associated with aggression and impulsivity. We investigated the effects of acute tryptophan depletion (ATD), and the resulting diminished central nervous serotonergic neurotransmission, on reactive aggression in healthy controls and adults with ADHD. Methodology/Principal Findings: Twenty male patients with ADHD and twenty healthy male controls were subjected to ATD with an amino acid (AA) beverage that lacked tryptophan (TRP, the physiological precursor of 5-HT) and a TRPbalanced AA beverage (BAL) in a double-blind, within-subject crossover-study over two study days. We assessed reactive aggression 3.25 hours after ATD/BAL intake using a point-subtraction aggression game (PSAG) in which participants played for points against a fictitious opponent. Point subtraction was taken as a measure for reactive aggression. Lowered rates of reactive aggression were found in the ADHD group under ATD after low provocation (LP), with controls showing the opposite effect. In patients with ADHD, trait-impulsivity was negatively correlated with the ATD effect on reactive aggression after LP. Statistical power was limited due to large standard deviations observed in the data on point subtraction, which may limit the use of this particular paradigm in adults with ADHD

New Ways of Diagnosing ADHD in Adults The Essen-Interview-for-School-Days-Related-Biography (EIS-B)

Objective Diagnosing Attention-Deficit-Hyperactivity Disorder (ADHD) in adults requires that ADHD has already been present in childhood. However, recall of ADHD-symptoms in childhood is fallible, for example influenced by mood. Furthermore, diagnostics need a procedure to handle oblivion and judgment biases. The Essen-Interview-for-school-days-related-biography (EIS-B) addresses these problems and offers a tool for retrospectively diagnosing childhood ADHD in adults. Method 36 patients with ADHD, 27 patients with depression or adjustment disorders and 39 healthy controls were included in the pilot study. All participants were comparable regarding age and gender. Results Internal consistency varied between alpha = 0.58 and alpha = 0.97, split-half-reliability was r = 0.98, inter-rater-reliability yielded kappa = 0.66. Retest-reliability varied between r = 0.40 and r = 0.88. Sensitivity was 82 %. Specificity yielded 100 %. Discussion The results indicate that EIS-B is a reliable and valid interview to retrospectively elucidate symptoms of childhood ADHD in adult patients. Further studies should aim for replication of our results using a larger sample size

Serum albumin correlates with affective prosody in adult males with attention-deficit hyperactivity disorder

The aim of this study was to determine the relationship between serum albumin, affective prosody, and symptoms of attention-deficit hyperactivity disorder (ADHD) found coincidentally in a recently published study. Here, serum albumin levels were assessed as a covariate. Twenty healthy male adults (controls) and 20 adult male patients with ADHD participated in the study on two study days. Serum albumin levels and performance in an affective prosody task were assessed, and correlations were determined. Serum albumin had a significant correlation with performance on an affective prosody task on both of the 2 study days. The same correlations were not significant in the healthy control group. There was no difference in the serum albumin level between patients with ADHD and healthy controls. The association between serum albumin and affective prosody in adults with ADHD is a novel finding. However, to date, there is no clear theory that explains this association. Future research should analyze whether serum albumin influences causes changes in performance in affective prosody using experimental designs