Biological rhythm has a key role in major depressive disorder (MDD) but the efficacy of antidepressants in Biological rhythm is less explored. 

Thus a study explored the efficiency of escitalopram and mirtazapine in refining circadian rhythm, diurnal mood variation (DMV) and daily activity in patients with MDD.

450 participants diagnosed with MDD received treatment with escitalopram (TWE), treatment with mirtazapine (TWM) or treatment as usual (TAU).  The Hamilton depression scale (HAMD) and the quick inventory of depressive symptomatology self-report (QIDS) assessed the Biological rhythm symptoms at baseline, weeks 2, 4, 6 and 8.

All treatment groups showed significant differences in HAMD scores, but these were significant only in patients without DMV. TWM showed marked improvement in Sleep rhythm items (difficulty falling asleep and early-wake), decreased appetite and weight on both HAMD and QIDS scales. TWE demonstrated marked improvement relating to daily activity-related items, feeling slowed down and concentration. TWE and TWM both significantly improved retardation.

Thus escitalopram, as well as mirtazapine, proved their superior anti-depressive effect, particularly for MDD patients without DMV. Escitalopram displayed higher effectivity relating to daily activity, feeling slowed down and concentration difficulty.

Journal of Affective Disorders, 2022;296(1):258-264. https://www.sciencedirect.com/science/article/abs/pii/S0165032721010090