Can P300 aid in the differential diagnosis of unipolar disorder versus bipolar disorder depression? A meta-analysis of comparative studies

• Published in: Journal of affective disorders 2019-02, Vol.245, p.219-227
• Main Authors: Zhong, Bao-Liang, Xu, Yan-Min, Xie, Wu-Xiang, Li, Yi
• Format: Article
• Language: English
• Subjects: Adult; Bipolar disorder; Bipolar Disorder - diagnosis; Depressive Disorder, Major - diagnosis; Diagnosis, Differential; Differential diagnosis; Event-Related Potentials, P300; Female; Humans; Major depressive disorder; Male; Middle Aged; P300
• ISSN: 0165-0327; 1573-2517
• DOI: 10.1016/j.jad.2018.11.010

•It is difficult to differentiate bipolar disorder (BD) from unipolar disorder (UD) depression.•This meta-analysis examined the extent of difference in P300 between BD and UD depression.•BD patients had significantly longer P300 latency than UD patients during depressive episode and remission.•Remitted BD patients had significantly longer P300 latency than healthy controls.•P300 latency of remitted UD patients decreased to normal during remission. It is difficult to distinguish between bipolar disorder (BD) and unipolar disorder (UD) depression. Given the different pattern of cognitive impairments between BD and UD, P300 is potentially useful for the differential diagnosis. This meta-analysis was performed to estimate the extent of difference in P300 in patients with BD versus UD depression. Studies comparing P300 between depressed BD and UD patients with or without healthy controls (HCs) were retrieved from major English and Chinese databases. Studies with BD and UD samples that were comparable in terms of age, gender, and depression severity, were rated as having high quality. Standardized mean differences (SMDs) of P300 latency and amplitude were calculated. In total, eight studies with a total of 397 depressed BD patients, 390 depressed UD patients, and 497 HCs, were included. Among included studies, six were rated as having good quality and three followed BD (n = 146) and UD (n = 144) patients during remission. BD patients had significantly longer P300 latency than UD patients during major depressive episode [SMD (95%CI): 0.580 (0.309, 0.850)] and remission [SMD (95%CI): 1.583 (1.322, 1.844)]. Compared to HCs, remitted BD patients still had significantly longer P300 latency [SMD (95%CI): 0.857 (0.059, 1.656)] but P300 latency of remitted UD patients had decreased to normal [SMD (95%CI): 0.536 (−0.272, 1.343)]. Sample sizes of depressed and remitted patients with BD and UD of included studies are small. P300 latency can be used as an auxiliary diagnostic marker for differentiating BD from UD depression.