This narrative review summarizes and discusses the implications of the Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 and the upcoming International Classification of Diseases (ICD)-11 classification systems on the prevalence of bipolar disorder and on the validity of the DSM-5 diagnosis of bipolar disorder according to the Robin and Guze criteria of diagnostic validity. Here we review and discuss current data on the prevalence of bipolar disorder diagnosed according to DSM-5 versus DSM-IV, and data on characteristics of bipolar disorder in the two diagnostic systems in relation to extended Robin and Guze criteria: 1) clinical presentation, 2) associations with para-clinical data such as brain imaging and blood-based biomarkers, 3) delimitation from other disorders, 4) associations with family history / genetics, 5) prognosis and long-term follow-up, and 6) treatment effects. The review highlights that few studies have investigated consequences for the prevalence of the diagnosis of bipolar disorder and for the validity of the diagnosis. Findings from these studies suggest a substantial decrease in the point prevalence of a diagnosis of bipolar with DSM-5 compared with DSM-IV, ranging from 30-50%, but a smaller decrease in the prevalence during lifetime, corresponding to a 6% reduction. It is concluded that it is likely that the use of DSM-5 and ICD-11 will result in diagnostic delay and delayed early intervention in bipolar disorder. Finally, we recommend areas for future research.

Aalborg University Hospital Psychiatry Aalborg Denmark; Department of Clinical Medicine Aalborg University Aalborg Denmark

Bipolar and Depressive Disorders Unit Hospital Clinic Institute of Neuroscience University of Barcelona IDIBAPS CIBERSAM Barcelona Catalonia Spain

Copenhagen Affective Disorder research Centre Psychiatric Centre Copenhagen Department O University Hospital of Copenhagen Rigshospitalet and University of Copenhagen Blegdamsvej 9 2100 Copenhagen Denmark

Department of Genetic Epidemiology in Psychiatry Central Institute of Mental Health Medical Faculty Mannheim University of Heidelberg Mannheim Germany

Department of Mental Health and Sensory Organs University of Siena School of Medicine Siena Italy

Department of Psychiatry Amsterdam UMC Vrije Universiteit Amsterdam the Netherlands

Department of Psychiatry and Department of Obstetrics Gynecology and Reproductive Science Icahn School of Medicine and Mount Sinai New York USA; Department of Psychiatry Erasmus Medical Center Rotterdam the Netherlands

Department of Psychiatry and Neurochemistry University of Gothenburg Gothenburg Sweden

Department of Psychiatry and Psychotherapeutic Medicine Medical University of Graz Graz Austria

Department of Psychiatry and Psychotherapy University Hospital Carl Gustav Carus TU Dresden Dresden Germany

Department of Psychiatry BIOARABA Hospital Universitario de Alava UPV EHU CIBERSAM Vitoria Spain

Department of Psychiatry Dalhousie University Halifax NS Canada; National Institute of Mental Health Klecany Czech Republic

Department of Psychiatry Dokuz Eylül University İzmir Turkey

Department of Psychiatry Psychosomatic Medicine and Psychotherapy University Hospital Frankfurt Frankfurt am Main Germany

Department of Psychiatry Psychotherapy and Psychosomatics Vivantes Hospital am Urban and Vivantes Hospital im Friedrichshain Charite Medicine Berlin and University of Cologne Germany

Department of Psychiatry Service Hospitalo Universitaire GHU Paris Psychiatrie and Neuroscience Paris France

Department of Psychiatry St Olav University Hospital and Department of Mental Health Norwegian University of Science and Technology NTNU Trondheim Norway

Department of Psychiatry University Hospital Carl Gustav Carus at the Technische Universität Dresden Dresden Germany

Department of Psychiatry University of Oxford and Oxford Health NHS Foundation Trust Oxford United Kingdom

Institute of Neuroscience Newcastle University Newcastle United Kingdom

Institute of Psychiatric Phenomics and Genomics University Hospital LMU Munich Germany

NORMENT Centre Division of Mental Health and Addiction Oslo University Hospital and Institute of Clinical Medicine University of Oslo Oslo Norway

Osakidetza Basque Health Service Bioaraba Health Research Institute University of the Basque Country UPV EHU Spain; Psychology Clinic of East Anglia 68 Bishopgate NR1 4AA Norwich United Kingdom

Section of Psychiatry Department of Medical Sciences and Public Health University of Cagliari Cagliari Italia; Department of Pharmacology Dalhousie University Halifax NS Canada

Université de Paris and INSERM UMRS 1144 Paris France