The Relationship Between Theta Power, Theta Asymmetry and the Effect of Escitalopram in the Treatment of Depression

Min Gao; Wenhua Sang; Kun Mi; Jiancong Liu; Yudong Liu; Wenge Zhen; Bang An

doi:10.2147/NDT.S425506

The Relationship Between Theta Power, Theta Asymmetry and the Effect of Escitalopram in the Treatment of Depression

Neuropsychiatr Dis Treat. 2023 Oct 24:19:2241-2249. doi: 10.2147/NDT.S425506. eCollection 2023.

Authors

Min Gao^#^{1

2}, Wenhua Sang^#^{1

3

4}, Kun Mi^{1

3

4}, Jiancong Liu^{1

3

4}, Yudong Liu^{1

3

4}, Wenge Zhen^{1

3

4}, Bang An²

Affiliations

¹ Department of Affective Disorders II, Hebei Provincial Mental Health Center, Baoding, People's Republic of China.
² Xianyang Central Hospital, Xianyang Mental Health Center, Xianyang, People's Republic of China.
³ Hebei Key Laboratory of Major Mental and Behavioral Disorders, Baoding, People's Republic of China.
⁴ The Sixth Clinical Medical College of Hebei University, Baoding, People's Republic of China.

^# Contributed equally.

Abstract

Objective: Only about one-third of depressed patients respond to initial antidepressant treatment. Therefore, it is crucial to find effective predictors of antidepressants. The purpose of our study was to learn the relationship between EEG theta power, theta asymmetry, and the efficacy of escitalopram.

Methods: The study included 34 patients with depression. Before and after each patient's course of treatment, EEG data was gathered. Both the Hamilton Anxiety Scale (HAMA) and the 17-item Hamilton Depression Scale (HAMD-17) were evaluated simultaneously. The natural logarithm of right frontal theta power minus left frontal theta power was used to calculate inter-electrode theta asymmetry (A_T).

Results: First, our study found no statistically significant difference between intra-electrode theta power and inter-electrode A_T before and after treatment (P ≥ 0.05). When we later looked at the data regarding treatment effects, the findings revealed that patients (n = 9) who did not respond to treatment had lower baseline theta power at C4 [6.190 (2.000, 12.990) vs 15.800 (7.255, 22.330), z = -2.166, P = 0.030]. The two groups had no difference in other electrodes (P ≥ 0.05). The A_T of C3/C4 in non-responders (n = 9) was lower [0.012 (0.795) vs 0.733 (0.539), t = -3.224, P = 0.005]. However, there was no difference in inter-electrode A_T between the two groups in F3/F4 and F7/F8 (P ≥ 0.05). We finally show that the theta power at C4 was negatively correlated with HAMD scores before treatment (r = -0.346, P = 0.045).

Conclusion: Our findings determined that increased theta power and positive asymmetry in the right frontal-central area correlate with favourable escitalopram treatment, providing a basis for finding predictive markers for antidepressants.

Keywords: EEG; depression; theta asymmetry; theta power; treatment effect.

Grants and funding

This study was supported by the Hebei Provincial Government Grant for Outstanding Talents Project, entitled “Characteristics of Event-Related Potentials and Predictive Role of Treatment in Depressed Patients”. (No.361014).