[Prevalence and recognition of bipolarity in patients with a treatment-resistant depressive disorder: a systematic...

Studies have indicated an association between treatment refractoriness in unipolar depression and unrecognised bipolar spectrum disorder (bsd). If confirmed, this may have implications for diagnosis and treatment.
AIM: To provide an overview on the prevalence and recognition of bsd in treatment resistant depression (trd).
METHOD: A search was made in PubMed concerning the prevalence of bsd in trd and clinical features that may be suggestive of bipolar depression.
RESULTS: Three articles were found that examined the prevalence of bsd in trd; they reported that 26-47% of patients with trd had an underlying bsd. Five cross-sectional studies described the predictors of clinical features in patients with a major depression. The following features occurred significantly more often: positive family history of bsd, young age of onset, higher number of recurrences, and atypical features.
CONCLUSION: There seems to be an association between trd and having an underlying bsd. A few clinical features may help to detect bsd in trd.