Identifying the symptoms
Bipolar affective disorder can be difficult to diagnose. Symptoms can be misdiagnosed as alcohol misuse or drug use; or even schizophrenia or schizoaffective disorders, especially where psychotic symptoms are present. Periods of mania and depression often alternate, or are separated by periods of normal mood. Mixed states of mania and depression are common.
Referral to a clinician may be made by others due to the patient’s lack of insight. Lesser degrees of mania and hypomania can be missed on a brief consultation, additional information from friends and relatives is vital.
The key to the clinical diagnosis of bipolar disorder is that it is partly made ‘longtitudinally’- taking a careful life history for evidence of possible previous mood episodes and their pattern of occurrence, and partly ‘cross-sectionally‘ looking at the ‘here and now’ for evidence of a current episode of mood disturbance. The diagnositic conclusion is made by putting this ‘longtitudinal life history information’ together with the ‘cross-sectional here-and-now information’. It also involves reasonable exclusion of other problems which can sometimes mimic the presentation of manic or depressive episodes.
Defining the diagnosis
There are two main diagnostic schemes defining bipolar affective disorder:
- the International Classification of Diseases of the World Health Organisation (10th edition ICD-10) and
- the Diagnostic and Statistical Manual (4th edition DSM-IV) of the American Psychiatric Association.
The schemes use mostly equivalent diagnostic categories, with DSM-IV dividing bipolar disorder into bipolar I and bipolar II. Because two different schemes are used to diagnose bipolar affective disorder, there can sometimes be subtle differences in how symptoms are described. Where possible, we will try to refer to the relevant diagnostic system (ie. ICD or DSM) when describing bipolar definitions and diagnoses.
The following guidelines were used to compile this section:
- Bipolar affective disorder: A national clinical guideline. Scottish Intercollegiate Guidelines Network. 2005.
- The management of bipolar disorder in adults, children and adolescents, in primary and secondary care. National Institute for Clinical Excellence. 2006.
- Yatham LN et al. Canadian Network for Mood and Anxiety Treatments (CANMAT) and International Society for Bipolar Disorders (ISBD) collaborative update of CANMAT guidelines for the management of patients with bipolar disorder: update 2009 (PDF). Bipolar Disord. 2009 May;11(3):225-55.
- Goodwin GM. Consensus Group of the British Association for Psychopharmacology. Evidence-based guidelines for treating bipolar disorder: revised second edition – recommendations from the British Association for Psychopharmacology (PDF). J Psychopharmacol. 2009 Jun;23(4):346-88.
- Hirschfeld, RMA et al Practice guideline for the treatment of patients with bipolar disorder, second edition. American Psychiatric Association. 2002.