Scope of add on repetitive transcranial magnetic stimulation in treating depression in Parkinson’s disease

• Published in: CNS spectrums 2023-06, Vol.28 (3), p.267-268
• Main Author: Kar, Sujita Kumar
• Format: Article
• Language: English
• Subjects: Clinical trials; Deep brain stimulation; Depression - etiology; Depression - therapy; Electroconvulsive therapy; Humans; Mental depression; Older people; Parkinson Disease - complications; Parkinson Disease - therapy; Parkinson's disease; Quality of life; Transcranial Magnetic Stimulation
• ISSN: 1092-8529; 2165-6509
• DOI: 10.1017/S1092852922000049

A complex interplay of genetic and environmental factors attribute to the development and progression of illness.2 The core clinical manifestations of Parkinson’s disease are rigidity, resting tremor, and bradykinesia, often known as the classical symptom triad of Parkinson’s disease.3,4 Other symptoms of Parkinson’s disease include—dysarthria, dysphagia, short-shuffling gait, dystonia, sialorrhoea, autonomic dysfunction, cognitive disturbances, and neurobehavioral abnormalities.3 Depression is one of the common psychiatric comorbidities among patients who have Parkinson’s disease, with prevalence ranging from 20% to 40%.5 Comorbid depression adversely affects the quality of life, increases the disability, and hampers the cognitive performances of patients with Parkinson’s disease.6,7 Antidepressants are the mainstay treatment of depression. Another randomized controlled trial also supports that high-frequency rTMS on the foot area of the motor cortex results in improvement of motor symptoms of Parkinson’s disease.12 Several recent meta-analyses also support the role of high-frequency rTMS targeting the motor area to alleviate motor symptoms of Parkinson’s disease.13-15 The more is the number of pulses delivered per session, the better the therapeutic effect.13 Makkos et al16 carried out a randomized controlled trial, where high-frequency rTMS has been used over the bilateral motor cortex, which resulted in a significant reduction of the depressive symptoms and improvement in the quality of life. Left DLPFC stimulation using high-frequency rTMS was useful in improving the depressive features, anxiety cognition, and motor features.17-19 Evidences support that there are various technical parameters and target site of stimulation, predicting the therapeutic response in depression.20 Identifying the appropriate target area and appropriate protocol of TMS will guide clinicians in better management of depression in Parkinson’s disease.