In low- and middle-income countries, only 25% of patients diagnosed with depression receive some form of treatment, with the current options being standard drug therapy and/or psychotherapy (WHO, 2023) (1). However, only about 35% of patients achieve complete remission of symptoms, resulting in more than half of patients with treatment-resistant depression (4).
Several studies have evaluated the efficacy of bilateral high-frequency (10 Hz) (5,6) and low-frequency (1 Hz) (50) Li-TMS applied to the dorsolateral prefrontal cortex (DLPFC) in patients with depression and insomnia over a 6-week period, totaling 30 sessions. These studies showed improvement in depressive symptoms and sleep quality in adults beginning at session 10 (5) and 15, respectively, as assessed by the Pittsburgh Sleep Quality Index (PSQI) and the Patient Health Questionnaire-9 (PHQ9) (7).
The exact mechanism by which Li-TMS improves sleep quality in patients with depression remains unclear. However, evidence indicates that patients who underwent high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) demonstrate improvement in sleep patterns, improvement in sleep stage, positive correlations in motor evoked potential, negative correlations with GABA and BDNF levels, as well as decreased levels of thyroid hormone, adrenocorticotropic hormone, and thyroid-stimulating hormone (5).
