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Clinical response to electroconvulsive therapy among patients with treatment-refractory psychosis: the BC Psychosis Program experience
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Abstracts / Brain Stimulation 10 (2017) 346e540
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Keywords: Posterior Parietal Cortex, Orienting Attention, tDCS [0621] EFFICACY OF RTMS TO TREAT INSOMNIA IN PATIENTS WITHOUT DEPRESSION A. Tello*, M. Gerez. Hospital Espanol, Mexico Purpose: Insomnia has been a major concern throughout the history of medicine, and long before depression was recognized as a medical condition. Thereafter, the strong association between sleep and affect disturbances has impeded independent characterization. Current research focuses on whether the relationship is causal or derived from shared mechanisms. Insomnia constricts quality of life, and medications produce side effects. Pharmacological and psychotherapeutic interventions, while effective for depression-associated sleep disturbances, have little impact on primary insomnia, pointing towards network dysregulation rather than neurotransmitter unbalance. Repetitive transcranial magnetic stimulation (rTMS) has shown regulatory effects on sleep patterns. We looked for the effects of rTMS on patients with treatment resistant primary insomnia. Methods: 25 patients (15 females; mean age 45, range 25-60) with chronic insomnia, resistant to pharmacotherapy and psychotherapy, without depression, wereincluded. Twenty rTMS sessions (1 Hz, 110% motor threshold, 1800 stimuli/day) over the right dorsolateral prefrontal cortex (rDLPFC). Other primary sleep pathologies were excluded. Pittsburgh Sleep Quality Index (PSQI), Hamilton Rating Scale for Depression (HRSD) and Becks Depression Inventory (BDI) were applied before, weekly, 3 and 6 months after rTMS. Results: PSQI decreased significantly in 80% of the patients with 32% relapsing rate at 6 months. Parameters were measured using paired t-test, and repeated measurements. Discussion: Our results show efficacy of rTMS on the PSQI scores. Although the level of evidence is limited for open-label studies, each patient was his/ her own control, given their history of failure to previous treatment. A possible explanation is that 1 hz rTMS hyperpolarizes neural cells of the frontal hyperactive networks. The low prevalence may reflect that the majority of insomnia patients eventually go beyond network dysregulation towards a biochemical unbalance, entering a depressioninsomnia feed forward cycle. The process would generate a distinct subtype of mayor depression, presumably more responsive to networkdirected therapies as the rTMS. Keywords: Low rTMS, Primary Insomnia, Network-directed therapies, rDLPFC
[0623] CLINICAL RESPONSE TO ELECTROCONVULSIVE THERAPY AMONG PATIENTS WITH TREATMENT-REFRACTORY PSYCHOSIS: THE BC PSYCHOSIS PROGRAM EXPERIENCE N.J. Ainsworth*1, 2, A. Leon 2, K. Green 2, R.F. White 1, 3, J. Sung 2, G. R. Shalbaf 2, A. Singh 2, W.G. Honer 1, F. VilaSmith 1, 3, Rodriguez 1, 2. 1 University of British Columbia, Canada; 2 Non-invasive Neurostimulation Therapies Laboratory, Canada; 3 British Columbia Psychosis Program, Canada Introduction: Patients with treatment-resistant psychosis (TRP) and clozapine-resistant psychosis (CRP) comprise some of the most difficult psychiatric illness to treat. The BC Psychosis Program (BCPP) in Vancouver, Canada treats some of the most severe cases TRP and CRP in the country. Given observational and early RCT evidence for electroconvulsive therapy in TRP/CRP, we wished to investigate its effectiveness in our uniquely refractory population. Methods: This was a prospective observational study involving patients admitted to the BCPP since 2012 who had received at least one session of ECT. Extensive demographic data were collected, including medication and clozapine history, and ratings scales including PANSS at admission and discharge. Changes in rating scales and response rates were calculated, with response defined as a 20% reduction in the PANSS positive symptom subscale. Results: Twenty-two patients met inclusion criteria for preliminary analysis. The most common primary diagnosis was schizophrenia (68%), followed by schizoaffective disorder (27%). Most patients were unemployed at admission (86%). Nearly all had a history of clozapine use (95%); at admission, 68% of patients were on clozapine currently (n¼17; median dose¼275mg, median duration¼280 days), and 52% were on two or more antipsychotic agents. For patients who completed both admission and discharge ratings (n¼10), average PANSS scores at admission were 29.5 (SD 5.36) for the positive symptom subscale and 107.4 (SD 12.88) for the total score; at discharge these were 21.1 (SD 6.4) and 85.82 (SD 21.86) respectively. At discharge, 80% of patients met response criteria. Discussion: The data presented here support the hypothesis that ECT is an effective intervention for CRP, including particularly severe cases that have failed post-clozapine strategies such as combined antipsychotic therapy. The response rate observed here also raises the possibility that ECT may be efficacious relative to clozapine as a treatment for TRP. Further work involving this cohort of patients will test these hypotheses using demographically-matched historical controls from the same population.
Abstracts / Brain Stimulation 10 (2017) 346e540
Keywords: Electroconvulsive therapy, Treatment-resistant psychosis, Clozapine, Schizophrenia [0627] TRANSCRANIAL MAGNETIC STIMULATION (TMS) COIL DESIGNING FOR HIGH ELECTROMAGNETIC FIELD GRADIENT GENERATION Q. Meng, E. Hong, F.-S. Choa*. University of Maryland, USA Introduction: Commercial transcranial magnetic stimulators (TMS) are designed to obtain highest transient magnetic field or induced electrical field for stimulation at desired locations, like figure-8 coil as shown in figure 1a. However, from cable equation model we know that membrane capacitor can only be charged by the spatial gradient of the induced electric filed to reach activation threshold. New generation TMS tools will be effectively designed to produce maximized gradient electrical field instead of electrical field. Methods: A new TMS stimulator design is proposed by using two coils, running current along opposite directions for obtaining maximized
499
magnetic field gradient. Since induced electric field is proportional to dB/ dt, we expect that a high spatial gradient of transient magnetic field will correspondingly produce a high grad(E), where E is induced electric field. Two-dimensional simulation was performed by FEMM, a finite element analysis tool. A larger radius coil and a relatively smaller radius coil, with radius ratio of 2 to 1, were top-down overlapped. By shifting the smaller coil along its horizontal direction to change their relative positions and adjust current flow ratio between them we can optimize the magnetic field gradient which is closely correlated to grad(E) as discussed above. Results: The highest magnetic field gradient was able to be achieved when the inner diameter of big coil wiring is aligned with the outside diameter of the smaller coil as figure 2a illustrates. By adjusting the current excitation in both coils, it was found that the optimized current ratio was from 1.5:1 to 1.7:1 for this case. Discussion: With two coils in anti-phase operations we can achieve the same or higher grad(B) amplitude at a lower total current compared with the conventional figure-8 structure. We expect new types of coil structure with optimized grad(E) design will replace conventional designs in the future.
Figure 1a. Two-dimentional cross section view of conventional figure-8 TMS coil in FEMM and its magnetic flux density distribution; b. Magnetic flux density distribution along a cutline 0.5cm below the figure-8 coil.
Figure 2a. Two-dimentional cross section view of coil design in FEMM and magnetic flux density distribution (170A current load in the up-side coil and 100A current load in the down-side coil); b. Magnetic flux density distribution along a cutline 0.5cm below the down-side coil.
Abstracts / Brain Stimulation 10 (2017) 346e540
Ă
Keywords: Posterior Parietal Cortex, Orienting Attention, tDCS [0621] EFFICACY OF RTMS TO TREAT INSOMNIA IN PATIENTS WITHOUT DEPRESSION A. Tello*, M. Gerez. Hospital Espanol, Mexico Purpose: Insomnia has been a major concern throughout the history of medicine, and long before depression was recognized as a medical condition. Thereafter, the strong association between sleep and affect disturbances has impeded independent characterization. Current research focuses on whether the relationship is causal or derived from shared mechanisms. Insomnia constricts quality of life, and medications produce side effects. Pharmacological and psychotherapeutic interventions, while effective for depression-associated sleep disturbances, have little impact on primary insomnia, pointing towards network dysregulation rather than neurotransmitter unbalance. Repetitive transcranial magnetic stimulation (rTMS) has shown regulatory effects on sleep patterns. We looked for the effects of rTMS on patients with treatment resistant primary insomnia. Methods: 25 patients (15 females; mean age 45, range 25-60) with chronic insomnia, resistant to pharmacotherapy and psychotherapy, without depression, wereincluded. Twenty rTMS sessions (1 Hz, 110% motor threshold, 1800 stimuli/day) over the right dorsolateral prefrontal cortex (rDLPFC). Other primary sleep pathologies were excluded. Pittsburgh Sleep Quality Index (PSQI), Hamilton Rating Scale for Depression (HRSD) and Becks Depression Inventory (BDI) were applied before, weekly, 3 and 6 months after rTMS. Results: PSQI decreased significantly in 80% of the patients with 32% relapsing rate at 6 months. Parameters were measured using paired t-test, and repeated measurements. Discussion: Our results show efficacy of rTMS on the PSQI scores. Although the level of evidence is limited for open-label studies, each patient was his/ her own control, given their history of failure to previous treatment. A possible explanation is that 1 hz rTMS hyperpolarizes neural cells of the frontal hyperactive networks. The low prevalence may reflect that the majority of insomnia patients eventually go beyond network dysregulation towards a biochemical unbalance, entering a depressioninsomnia feed forward cycle. The process would generate a distinct subtype of mayor depression, presumably more responsive to networkdirected therapies as the rTMS. Keywords: Low rTMS, Primary Insomnia, Network-directed therapies, rDLPFC
[0623] CLINICAL RESPONSE TO ELECTROCONVULSIVE THERAPY AMONG PATIENTS WITH TREATMENT-REFRACTORY PSYCHOSIS: THE BC PSYCHOSIS PROGRAM EXPERIENCE N.J. Ainsworth*1, 2, A. Leon 2, K. Green 2, R.F. White 1, 3, J. Sung 2, G. R. Shalbaf 2, A. Singh 2, W.G. Honer 1, F. VilaSmith 1, 3, Rodriguez 1, 2. 1 University of British Columbia, Canada; 2 Non-invasive Neurostimulation Therapies Laboratory, Canada; 3 British Columbia Psychosis Program, Canada Introduction: Patients with treatment-resistant psychosis (TRP) and clozapine-resistant psychosis (CRP) comprise some of the most difficult psychiatric illness to treat. The BC Psychosis Program (BCPP) in Vancouver, Canada treats some of the most severe cases TRP and CRP in the country. Given observational and early RCT evidence for electroconvulsive therapy in TRP/CRP, we wished to investigate its effectiveness in our uniquely refractory population. Methods: This was a prospective observational study involving patients admitted to the BCPP since 2012 who had received at least one session of ECT. Extensive demographic data were collected, including medication and clozapine history, and ratings scales including PANSS at admission and discharge. Changes in rating scales and response rates were calculated, with response defined as a 20% reduction in the PANSS positive symptom subscale. Results: Twenty-two patients met inclusion criteria for preliminary analysis. The most common primary diagnosis was schizophrenia (68%), followed by schizoaffective disorder (27%). Most patients were unemployed at admission (86%). Nearly all had a history of clozapine use (95%); at admission, 68% of patients were on clozapine currently (n¼17; median dose¼275mg, median duration¼280 days), and 52% were on two or more antipsychotic agents. For patients who completed both admission and discharge ratings (n¼10), average PANSS scores at admission were 29.5 (SD 5.36) for the positive symptom subscale and 107.4 (SD 12.88) for the total score; at discharge these were 21.1 (SD 6.4) and 85.82 (SD 21.86) respectively. At discharge, 80% of patients met response criteria. Discussion: The data presented here support the hypothesis that ECT is an effective intervention for CRP, including particularly severe cases that have failed post-clozapine strategies such as combined antipsychotic therapy. The response rate observed here also raises the possibility that ECT may be efficacious relative to clozapine as a treatment for TRP. Further work involving this cohort of patients will test these hypotheses using demographically-matched historical controls from the same population.
Abstracts / Brain Stimulation 10 (2017) 346e540
Keywords: Electroconvulsive therapy, Treatment-resistant psychosis, Clozapine, Schizophrenia [0627] TRANSCRANIAL MAGNETIC STIMULATION (TMS) COIL DESIGNING FOR HIGH ELECTROMAGNETIC FIELD GRADIENT GENERATION Q. Meng, E. Hong, F.-S. Choa*. University of Maryland, USA Introduction: Commercial transcranial magnetic stimulators (TMS) are designed to obtain highest transient magnetic field or induced electrical field for stimulation at desired locations, like figure-8 coil as shown in figure 1a. However, from cable equation model we know that membrane capacitor can only be charged by the spatial gradient of the induced electric filed to reach activation threshold. New generation TMS tools will be effectively designed to produce maximized gradient electrical field instead of electrical field. Methods: A new TMS stimulator design is proposed by using two coils, running current along opposite directions for obtaining maximized
499
magnetic field gradient. Since induced electric field is proportional to dB/ dt, we expect that a high spatial gradient of transient magnetic field will correspondingly produce a high grad(E), where E is induced electric field. Two-dimensional simulation was performed by FEMM, a finite element analysis tool. A larger radius coil and a relatively smaller radius coil, with radius ratio of 2 to 1, were top-down overlapped. By shifting the smaller coil along its horizontal direction to change their relative positions and adjust current flow ratio between them we can optimize the magnetic field gradient which is closely correlated to grad(E) as discussed above. Results: The highest magnetic field gradient was able to be achieved when the inner diameter of big coil wiring is aligned with the outside diameter of the smaller coil as figure 2a illustrates. By adjusting the current excitation in both coils, it was found that the optimized current ratio was from 1.5:1 to 1.7:1 for this case. Discussion: With two coils in anti-phase operations we can achieve the same or higher grad(B) amplitude at a lower total current compared with the conventional figure-8 structure. We expect new types of coil structure with optimized grad(E) design will replace conventional designs in the future.
Figure 1a. Two-dimentional cross section view of conventional figure-8 TMS coil in FEMM and its magnetic flux density distribution; b. Magnetic flux density distribution along a cutline 0.5cm below the figure-8 coil.
Figure 2a. Two-dimentional cross section view of coil design in FEMM and magnetic flux density distribution (170A current load in the up-side coil and 100A current load in the down-side coil); b. Magnetic flux density distribution along a cutline 0.5cm below the down-side coil.