〈Case Reports〉Diagnostic problems of childhood-onset bipolar disorder comorbid with attention-deficit hyperactivity disorder: three-year follow-up study of six cases

publisher[Abstract] The aim of this follow-up study was to investigate whether severe non-episodic irritability without elevated or expansive mood exhibited by children under 9 years old with attention deficit-hyperactivity disorder (ADHD) is the first prodromal symptom of childhood-onset bipolar disorder (BP). From among 32 children aged under 9 years old who were referred to our outpatient department for assessment and treatment of ADHD in 2008, 6 children exhibiting severe temper tantrums and anger outbursts were the participants in this study. All participants were followed every few months for 3 years after the initial assessment. At each follow-up visit to our hospital, we administered the Kiddie Schedule for Affective Disorders- Present (K-SADS) modules for ADHD, mania, and depression in an interview with the child and/or parent and/or teacher to assess their symptoms. Among the 6 participants, 2 experienced an episode of hypomania during the followup period, and 3 were symptom-free during the follow-up period once their irritability had subsided. One participant repeatedly experienced severe non-episodic irritability and was symptom-free for no more than 2 months at any one time during the follow-up period. Our findings suggest that children with ADHD under the age of 9 years may have a developmental presentation of BP when exhibiting severe non-episodic irritability, and environmental factors surrounding a child should be also considered when deciding the treatment