Achieving a better diagnosis of bipolar 1

Bipolar I, like other psychiatric disorders, can be difficult to diagnose because clinicians tend to rely upon interpreted clues from observing patient behaviours and feelings.  Given that patients often present for treatment when they’re depressed, rather than manic, this can often lead to being misdiagnosed with unipolar depression, for example, and receive treatment with antidepressants alone.

Identification of a mental illness by matching behaviours to genetic predispositions, therefore, presents an attractive option. Biomarkers also hold the promise of identifying latent disease before symptoms are clinically evident, which is especially important in patients who haven’t yet experienced hypomanic or manic episodes.

Not surprisingly, therefore, in response to our poll question at the ECNP 2014, 80% of respondents answered that they would advocate the use of biomarkers in early identification of bipolar disorder.

Dr Andreas Erfurth, Head of Clinical Psychopharmacology and the Bipolar Spectrum Disorders Program, Division of General Psychiatry, Medical University of Vienna, Austria said: “The search for biomarkers is a promising field of psychiatric research. So far, identification of biomarkers for bipolar disorder has shown to be difficult.

“The genetics of bipolar disorder highly overlap with the genetics of schizophrenia: a study on single-nucleotide polymorphisms(SNPs) heritability showed that there are more SNPs in common to explain heritability in bipolar disorder and schizophrenia than SNPs that seem to be specific¹. International classifications acknowledge a continuum between bipolar episode without psychotic features, bipolar episode with psychotic features, schizoaffective disorder and schizophrenia. It will be difficult to find specific biomarkers for early identification in this continuum.

“The wish for biomarkers is a dream that is in common for every clinician. Early identification, early psychoeducation and early prophylactic treatment are crucial for avoiding a complicated course of the disease.

“While careful examination of the patient and of his family history remain the only possibilities for early identification today, further research in biomarkers for bipolar disorders is clearly needed,” said Dr Erfurth.

Diagnostic questionnaires

In the absence of biomarkers, clinicians have access to tools that allow them to assess the psychopathology (e.g. the Association for Methodology and Documentation in Psychiatry orAMDP system), the course (life chart method) and the diagnosis of affective disorders (MINI, Hypomania Checklist, for subthreshold affectivity: TEMPS). It was good to note that 100% of our respondents confirmed that they use diagnostic tools in their daily practice.

A more recent addition to the clinicians’ armamentarium is the Mini International Neuropsychiatric Interview (MINI). This is particularly useful to assess DSM depressive features in manic and hypomanic episodes. With an administration time of approximately 15 minutes, the MINI is both brief and accurate enough for non-research settings.

Dr Erfuth said: “Diagnostic tools are clearly crucial for the assessment of patients in clinical practice, as shown in the response from colleagues today. The quick adaptation of instruments such as the MINI (e.g. when diagnostic criteria change, as they did with the introduction of DSM-5) is needed, as well as a prompt translation into local languages.

“Furthermore, specific sections of the MINI can be used to address specific questions. To identify manic episodes with mixed features the corresponding section of the MINI can be easily used² ; it comprises six questions that have been designed to be filled in directly by the patient.”

DSM-5 improves management of bipolar I

On the subject of the new DSM-5, 88% of respondents agreedthat theDSM-5 mixed specifier has made it easier to accurately describe their patients’ complex disease state.

DSM-5 acknowledges a dimensional approach between depression, depression with mixed features, mania with mixed features, and mania within bipolar disorder, thus describing the overlapping character of mood episodes much better than DSM-IV.

Dr Erfurth concluded: “DSM-5 acknowledges the spectrum nature of affective disorders and the introduction of the diagnosis of mania with a mixed features specifier creates new opportunities for precisely targeting this important clinical subtype through specific therapy and appropriate pharmacotherapy.”