Management of bipolar disorder is limited by absence of laboratory test. While alterations related to multiple biological pathways have been found in bipolar disorder, findings have not translated into clinically applicable biomarkers. We previously found promise for a combined gene expression biomarker. The combination of gene expression and proteomic biomarkers could have potential as a meaningful clinical test.

To identify a composite biomarker based on multiple potential peripheral biomarkers related to neuroplasticity, inflammation and oxidative stress, both on a proteomic and gene expression level.

To test the ability of a composite biomarker to discriminate between bipolar disorder patients and healthy control subjects and between affective states in bipolar disorder patients.

mRNA expression of a set of 19 candidate genes and protein levels of immune markers and neurotrophic factors were measured in peripheral blood mononuclear cells and combined with urinary levels of oxidized nucleosides of 37 rapid cycling bipolar disorder patients in different affective states (depression, mania and euthymia) during a 6–12-month period and in 40 age- and gender-matched healthy control subjects. A composite measure was constructed in the first half of the sample and independently validated in the second half of the sample. The composite measure was evaluated using ROC curves and by calculating sensitivity and specificity.

Statistical analysis is ongoing. Results will be presented at the congress.

A peripheral composite biomarker based on multiple biological pathways on both proteomic and gene expression levels may have potential as a clinically applicable biomarker.

The authors have not supplied their declaration of competing interest.