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.