Patients with depression who report psychotic-like symptoms tend to be those who are less likely to respond well to treatment, rather than having unrecognized bipolar disorder, researchers from Massachusetts General Hospital and Harvard Medical School, report in Archives of General Psychiatry. Psychotic-like symptoms, such as hearing voices or believing they are being spied on or schemed against, reported by some patients with depression, do not appear to be linked to treatment resistance, the authors write.

The researchers wrote:

    “The distinction between major depressive disorder and bipolar disorder remains a challenging clinical problem when individuals present with a major depressive episode. The identification of individuals at risk for bipolar disorder is of more than academic importance, as treatment may be markedly different; in particular, antidepressants have been suggested to exacerbate the illness course of at least a subset of bipolar individuals.”

Roy H. Perlis, M.D., M.Sc. and team wanted to find out what the link between bipolar disorder features and depression treatment outcomes might be. They gathered data on 4,041 adults, all of whom had been diagnosed with depression. They were treated with citalopram, an antidepressant, and monitored for up to three next-step treatments, as required, depending on how they responded.

They were all asked whether they had psychotic symptoms, such as believing they had special powers, people scheming against them, or thinking that they were being controlled. 30% (1,198) of them said they had had at least one of the psychotic symptoms during a six-month period up to being asked. Those reporting such symptoms were much less likely to respond well to treatment – their likelihood of going into remission during their treatment period was much lower, compared to the other patients.

They were also asked about other features which exist in bipolar disorder. 38.1% of them (1,524) reported one or more manic-like symptoms. Poor treatment outcomes was associated with one of those symptoms – irritability.

The researchers said:

    “On the other hand, several indicators consistently associated with bipolar disposition in the literature, including history of manic symptoms and family history of bipolar disorder, were not associated with outcome of treatment with antidepressants in the STAR*D study. Briefer episode duration, suggested to represent a risk marker for bipolarity, was associated with greater likelihood of remission.

    (conclusion) Considered as a whole, our results cast doubt on the frequent assertion that unrecognized bipolar disorder is widespread in clinical practice and particularly in treatment-resistant major depressive disorder. Screening for bipolar disorder among psychiatric patients remains important, as does considering individual risk factors such as family history or age at onset. Still, our findings indicate that, in most individuals presenting with a major depressive episode without a prior manic or hypomanic episode, unrecognized bipolarity does not appear to be a major determinant of treatment resistance.”

“Association Between Bipolar Spectrum Features and Treatment Outcomes in Outpatients With Major Depressive Disorder”
Roy H. Perlis, MD, MSc; Rudolf Uher, PhD, MRCPsych; Michael Ostacher, MD; Joseph F. Goldberg, MD; Madhukar H. Trivedi, MD; A. John Rush, MD; Maurizio Fava, MD
Arch Gen Psychiatry. Published online December 6, 2010. doi:10.1001/archgenpsychiatry.2010.179

Written by Christian Nordqvist