Efficacy of Repetitive Transcranial Magnetic Stimulation for Improving Depressive Symptoms in Patients With Parkinson's Disease

Inclusion Criteria: * Willing and able to provide written informed consent * Male or female aged 40 to 90 years * Diagnosed with Parkinson's disease with depressive symptoms * Hoehn and Yahr stage 1 to 3 * On stable Parkinson's disease medication for at least 3 months prior to screening, with no planned dose increase during the study period * Clinically significant depressive symptoms (BDI-II score ≥14) confirmed by clinician interview, without major psychiatric conditions that may confound their assessment * Able to read and write Korean and capable of independently completing questionnaires Exclusion Criteria: * History of epilepsy * Parkinson's disease caused by cerebrovascular disease, CNS infection, intoxication, or traumatic brain injury * Diagnosed with Parkinson-plus syndromes (multiple system atrophy, progressive supranuclear palsy, corticobasal degeneration, dementia with Lewy bodies etc.) * Clinically significant abnormal laboratory values (AST, ALT, or total bilirubin \> 2.5 x ULN) * Major psychiatric disorders other than depressive disorders (e.g., bipolar disorder, psychotic disorders) that may interfere with study participation or assessment of depressive symptoms * Unable to follow instructions or communicate * Pregnant, breastfeeding, or women of childbearing potential * Febrile patients * Patients with artificial hip joint implants * Presence of conductive, ferromagnetic, or magnetically sensitive metal near the head or treatment coil (e.g., cochlear implants, implanted electrodes/stimulators, aneurysm clips or coils) * Cardiac disease, especially patients with pacemakers * Corrected or uncorrected visual acuity less than 0.5 * Use of drug infusion pumps or hearing aids * Patients with acute illness * Patients taking tricyclic antidepressants, neuroleptics, or other medications that may lower seizure threshold * History of increased intracranial pressure or head trauma * Evidence of external wounds on brain or neck * Prominent psychotic symptoms other than depression (high NPI scores for hallucinations, delusions, mania) * History of schizophrenia, bipolar disorder, or substance abuse * Suicidal ideation (BDI-II item 9 score of 2 or 3) * History of or planned deep brain stimulation or stereotactic surgery (pallidotomy, thalamotomy) * Any participant deemed ineligible by the investigator, including those with medical conditions that may increase risk or interfere with study evaluation * Currently enrolled in another clinical trial or used investigational drug/device within 30 days or 5 half-lives prior to consent