Diagnostic transition towards schizophrenia in adolescents with severe bipolar disorder type I: An 8-year follow-up study

Background: The diagnosis of bipolar disorder-I (BD-I) is currently well-established. However, more studies exploring diagnostic stability and psychosocial adaptation during follow-up in adulthood are needed. Objectives: We assessed factors at follow-up (FU): (1) the diagnostic stability of manic/mixed episodes from adolescence to adulthood, (2) psychosocial adaptation, and (3) factors associated with psychosocial adaptation. Methods: A sample of 80 adolescents hospitalized in a university hospital between 1993 and 2004 for a manic or mixed episode were contacted for an FU assessment on average 8. years after the index episode. Assessments included socio-demographic data, mortality, lifetime psychiatric diagnosis, the Social Adaptation Scale, negative life events and insight. Results: Of the 64 patients with available information, one patient died from a heart attack. Of the 55 patients available for an FU assessment, 35 (63.6%) still presented a diagnosis of BD-I at FU, whereas 20 (36.4%) had changed diagnosis towards a schizophrenia spectrum disorder. Psychosocial adaptation was moderate to poor for most patients, and 91% of the patients had at least one relapse. A low socio-economic status, intellectual disability, negative life events, a history of sexual abuse, and treatment with classical antipsychotics at FU were significantly associated with poorer psychosocial adaptation. In contrast, better insight, a family history of depression and a diagnosis of BD-I at FU were associated with better psychosocial adaptation. Conclusion: BD-I in adolescent inpatients can lead to important morbidity and mortality during outcome. Diagnostic stability is high, but a high proportion of patients also show a transition towards a schizophrenia spectrum disorder.