Effects of routine repetitive transcranial magnetic stimulation on the sleep duration of patients with treatment-resistant depression: A prospective cohort study.

Aim: The aim of this study was to evaluate the short-term and long-term effects of routine repetitive transcranial magnetic stimulation (rTMS) on the sleep duration, depressive symptoms, and quality of life of patients with treatment-resistant depression (TRD).

Methods: In this prospective cohort study, 25 participants with TRD were assessed using the Insomnia Severity Index (ISI) and four sleep duration components of the Pittsburgh Sleep Quality Index (PSQI). Depression severity was measured with Hamilton's Depression Rating Scale (HDRS) and Beck's Depression Inventory (BDI-II), and patient-perceived quality of life with the 36-Item Short-Form Survey (SF-36). All of these measures were evaluated at baseline (T0), and immediately (T1), 6 weeks (T2), and 12 weeks (T3) after the end of intervention.

Results: At T1 endpoint, HDRS, BDI, SF-36, ISI, and three PSQI items (time to wake up, time taken to fall asleep, and Real Sleep Time) significantly improved, though these gains were reduced at follow-up endpoints (T2 and T3). Adjusting for confounders (age, sex, occupational status, BMI, and hypnotic medication) revealed that only improvements in HDRS, BDI, and time taken to fall asleep at T1 remained statistically significant. Linear regression analyses showed no significant association between reduced time taken to fall asleep and depression symptoms, suggesting rTMS can independently enhance this parameter, irrespective of depression resolution.

Conclusion: Routine rTMS therapy can potentially enhance sleep duration in TRD individuals, alongside improved depressive symptoms and quality of life. However, these benefits tend to decrease over long-term follow-up, emphasizing a more pronounced short-term efficacy of rTMS.