Objective: The diagnosis and treatment of youth with severe nonepisodic irritability and hyperarousal, a syndrome defined as severe mood dysregulation (SMD), has been the focus of increasing concern and debate among clinicians and researchers. Our main objective was to assess the effectiveness of risperidone for youths with SMD.
Methods: An 8-week open label trial with risperidone was conducted. We extensively assessed 97 subjects with semistructured and clinical interviews and enrolled 21 patients in the study. Risperidone was titrated from 0.5 to 3 mg/day in the first 2 weeks. Evaluations were performed at baseline and weeks 2, 4, 6, and 8. Clinical outcome measures were (1) Aberrant Behavior Checklist-Irritability Subscale, (2) Clinical Global Impressions, and (3) severity of co-morbid conditions.
Results: We found a significant reduction of the Aberrant Behavior Checklist-Irritability scores during the trial after risperidone use (p < 0.001). The scores at week 2 (mean = 12.03; standard error [SE] = 2.94), week 4 (mean = 15.48; SE = 2.93), week 6 (mean = 12.29; SE = 2.86), and week 8 (mean = 11.28; SE = 3.06) were significantly reduced compared with the baseline mean score (mean = 25.89; SE = 2.76) (p < 0.001). We also found an improvement in attention-deficit/hyperactivity disorder, depression, and global functioning (p < 0.001).
Conclusion: Risperidone was effective in reducing irritability in SMD youth. To the best of our knowledge, this is the first psychopharmacological trial in this group of patients with positive results. Further randomized, controlled studies are needed.