Objectives: Treatment investigations with methylphenidate in adults with ADHD focus preferentially on the classical psychopathology: inattention, hyperactivity and impulsivity. ADHD-associated emotional symptoms, which are frequently present at least in ADHD subpopulations, were studied rarely. The vast majority of the placebo-controlled trials had observation periods between 4 and 8 weeks. To assess the medium- to long-term effects of extended release methylphenidate (MPH-ER) on emotional symptoms and other psychopathology frequently seen in ADHD patients, we conducted a large-scale, multicenter treatment study.
Methods: We performed a randomised, 24-week, double-blind, placebo-controlled study in adults with ADHD. The diagnosis was made on the basis of the DSM-IV criteria, which were confirmed by clinical history and a structured psychopathological interview and the use of rating instruments. 363 patients were randomized to MPH-ER or placebo at a ratio of 2:1. The duration of the titration period was 5 weeks followed by a maintainance phase of 19 weeks. The efficacy measures were the observer rated 10-item Emotional Dysregulation Scale (EDS) derived from the Wender-Reimherr Adult Attention Deficit Disorder Scale (WRAADDS) and a self-report, six-item Emotional Lability Scale (ELS) extracted from the long version of the Conners Adult ADHD Self Report Scale (CAARS:S:L). In addition we used the SCL-90-R for the assessment of ADHD associated and comorbid psychopathology.
Results: MPH-ER was statistically superior to placebo in reducing emotional symptoms as assessed by the EDS and the ELS. Obsessive-compulsive symptoms and those of problems with self-concept declined until the end of the observation period. The decline was more pronounced in MPH-ER treated individuals. The effects remained robust during the entire maintenance period until week 24. Symptoms of anxiety, depression, anger and hostility, phobia, paranoid ideations and psychoticism were not improved.
Conclusions: MPH-ER appears to be an efficacious treatment for emotional symptoms with ADHD. Also obsessive-compulsive symptoms and problems with self-concept were affected positively.