Researchers Find Biomarker For Predicting Bipolar Disorder Risk in Depression Patients
Doctors may be able to predict which patients with a first episode of depression are likely to go on to develop bipolar disorder by measuring plasma levels of brain-derived neurotrophic factor, according to a new study.
“Finding a reliable and robust biomarker identifying bipolar disorder early during a patient’s first presenting episode of depression is critical”, study author Yiru Ganf from Shanghai Jiao Tong University School of Medicine, Chine, said in the report published in the British Journal of Psychiatry.
Researchers hope the findings will allow for earlier intervention and improved treatment and outcomes.
The researchers analysed messenger (m)RNA and protein levels of BDNF in the plasma of 164 drug-naive patients with a first episode of depression. The average age of participants was 31-years-old, and only a quarter were mae. The average length of depressive episodes was 2.8 months.
Both measurements of BDNF factors were notable lower in these patients compared to the 167 mentally healthy control participants matched for age and gender. Also, out of all the participants, the 21 who were diagnosed with bipolar disorder during 3 years of follow-up had significantly lower BDNF mRNA levels than those who maintained a diagnosis of major depressive disorder (MDD).
The researchers found that the combination of BDNF mRNA and protein levels was more accurate than mRNA or protein levels alone for distinguishing between patients with bipolar disorder and MDD. The findings were similar when patients lost to follow-up analysis were classified as having MDD.
“Despite promising results in our study, earlier reports show that BDNF levels among individuals with mood disorders is far from consistent,” Fang and colleagues note. The researchers suggest the variability can be attributed to small sample sizes and medication effects in previous studies. The more recent experiment was larger and restricted to drug-naive patients.
“These results suggest that BDNF level may be a potential biomarker for bipolar disorder that can be detected in the first depressive episode”, the team concludes.