Distinguishing Quantitative Electroencephalogram Findings between Adjustment Disorder and Major Depressive Disorder

OBJECTIVE: Adjustment disorder (ADJ) is a common diagnosis. However, it is difficult to distinguish ADJ from other major Axis I disorders, such as major depressive disorder (MDD). The aim of this study was to determine the distinguishing neurophysiological characteristics between ADJ and MDD using quantitative analysis of an electroencephalogram (QEEG). METHODS: The study included 30 patients with ADJ and 51 patients with MDD. Resting (eye closed) vigilance controlled EEG recordings were assessed at 19 electrode sites according to the international 10/20 system. QEEG absolute power and coherence were calculated for the delta, theta, alpha and beta bandwidths. RESULTS: Absolute powers of alpha and high beta bands, particularly at the frontocentral area, differed between MDD and ADJ group (p<0.05). Interhemispheric coherence values for the delta and beta bands were lower in the ADJ group than in the MDD group (p<0.05). Intrahemispheric coherence values for the alpha band were also lower in the ADJ group (p<0.05). CONCLUSION: The differences in QEEG power and coherence in our investigation suggest that underlying pathophysiologic mechanisms may be different between ADJ and MDD.