Role of Repetitive Transcranial Magnetic Stimulation in Maintenance Treatment of Resistant Depression
Ms. P, a 30 year old married female with well-adjusted pre-morbid personality, had an episodic depressive illness which made its onset in the year 2007 with a depressive episode which lasted for 9 months and was precipitated by academic failure and interpersonal conflict. Patient frequently contemplated self-harm and had socio-occupational dysfunction, poor personal care and disturbed biological functions. Her treatment records showed two trials of SSRIs [], with which she maintained partial remission with impaired functioning till November 2009, when she presented to the Psychiatry OPD with the 2nd major depressive episode of two months duartion. This was a breakthrough episode as patient was compliant with previous treatment []. The symptoms were characterized by sustained and pervasive depressive mood, anhedonia, feeling of decreased energy, poor appetite and insomnia. She had poor concentration, ideas of hopelessness, guilt, decreased self-esteem and occasional ideas of self-harm. No psychotic symptoms were present. All these were associated with anxiety, irritability and occasional crying episodes. She lost her job during the episode, called-off relationship with her boy-friend and would remain confined to her room. Medical history and investigations did not reveal any co-morbid physical illness. The SSRI was cross-tapered with a tricyclic antidepressant, with which she started experiencing daytime sedation and dryness of mouth at sub-maximal dose (Imipramine 150mg; ). Modafinil 200mg/day was added to decrease daytime sedation and as an augmenting agent, but the patient perceived no improvement even after 8 weeks with the above combination. Later, Lamotrigine 100mg/day was added as an augmenting agent. The above combination was continued for another 8 weeks without any significant improvement []. Due to poor response and continuing side-effects with the above combination, the patient declined to continue medication further and also refused to undergo further trial with pharmacotherapy.\nDue to progressive worsening of symptoms, along with treatment resistance (Thase-Rush Staging Method stage 3)[] and patient's refusal for pharmacotherapy;it was decided to start treatment with rTMS (Magstim Super Rapid magnetic stimulator; The Magstim Company Ltd). The parameters were 15Hz frequency, train duration 10sec, 20 trains per session and inter-train duration of 60sec (total 3000 pulses). Over the next three weeks 15 sessions were carried out with same parameters []. Patient's symptoms started showing improvement by 15 sessions. After further 5 sessions, her symptoms remitted further and she started pursuing all her daily activities. During the period of remission she started preparation for competitive examinations again and she got married as well.\nThe third depressive episode of one month duration was moderate in intensity which resolved with 5 sessions of rTMS and then, patient became non-compliant for further sessions. Over the next 2 years, there were two moderate depressive episodes of 3 months each. In each of the episode she required 20 rTMS sessions. The parameters in each of the session was intensity 100% of Motor Threshold, 20Hz frequency, train duration of 10sec, 20 trains per session and inter-train duration of 60sec. During the inter-episodic period of remission and even during the depressive episodes she did not have any significant psychosocial, familial or occupational dysfunction and she was able to continue her occupation as a journalist.