Can a simple blood test diagnose bipolar disorder? Highlights from new study

A recent JAMA study conducted in the UK has paved the way for a potential blood test that could significantly improve the diagnosis of bipolar disorder (BD) and distinguish it from major depressive disorder (MDD). Bipolar disorder is often misdiagnosed as major depressive disorder due to overlapping symptoms and the absence of objective diagnostic tools.

The study, which ran from April 2018 to February 2020, aimed to identify a consistent metabolomic biomarker signature in dried blood spots (DBSs) from patients that could differentiate between BD and MDD during depressive episodes.

The study analyzed data from 241 patients with depressive symptoms who had been recently diagnosed with MDD. Of this group, 67 were subsequently diagnosed with BD through the Composite International Diagnostic Interview, while 174 were confirmed as having MDD. The researchers identified a 17-biomarker panel.

When the biomarker data were combined with patient-reported information, the diagnostic performance was significantly improved. The models based on this combined data outperformed those based solely on demographic information and traditional diagnostic tools.

The identified biomarkers were primarily associated with lifetime manic symptoms. They were validated in a separate group of patients who received a new clinical diagnosis of MDD or BD during a one-year follow-up period.

Ref: Tomasik J, Harrison SJ, Rustogi N, et al. Metabolomic Biomarker Signatures for Bipolar and Unipolar Depression. JAMA Psychiatry. Published online October 25, 2023. doi:10.1001/jamapsychiatry.2023.4096