[Depression in the course of bipolar disorder and recurrent depressive disorder in the elderly: diagnostic difficulties].

UNLABELLED

Misdiagnosis of bipolar disorder in depressive patients is a common clinical problem estimated to be evident in up to 40% of patients. Elderly patients might be especially vulnerable to that sort of diagnostic error.

AIM

To estimate the rate of misdiagnosis in the elderly (60yrs+) hospitalized due to depression and to establish clinical correlates that might improve diagnosis.

METHOD

A retrospective analysis of medical records of all the patients hospitalized in the University based Psychogeriatric Ward and suffering from a depressive episode due to bipolar disorder or recurrent depressive disorder.

RESULTS

The rate of misdiagnosis was 54% in bipolar and 9% in recurrent depressive disorder. Bipolar patients were mainly misdiagnosed as having recurrent depression. A severe episode was more common in bipolar subjects (particularly in women) while recurrent depressive subjects tend to suffer from less severe but more protracted episodes. Somatic symptoms of depression were more prevalent among recurrent depressive subjects while psychotic features, particularly delusions, and, to the lesser extent, hallucinations, were more common in patients suffering from bipolar depression.

CONCLUSIONS

Bipolar depression is very often misdiagnosed in the hospitalized elderly. There are several features that might help the clinician to distinguish it from recurrent depression. Long history of illness, high number of previous episodes, severe episodes and the presence of psychotic symptoms are typical for bipolar elderly while a protracted current episode and the presence of somatic symptoms of depression might indicate the diagnosis of recurrent depression.