PTSD: Similar Effects of High- and Low-Frequency rTMS

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PTSD symptoms can be reduced by high- and low-frequency repetitive transcranial magnetic stimulation.
PTSD symptoms can be reduced by high- and low-frequency repetitive transcranial magnetic stimulation.

Both high- and low-frequency repetitive transcranial magnetic stimulation  (rTMS) are effective in reducing core cluster and associated symptoms of posttraumatic stress disorder (PTSD), according to a review by investigators from multiple institutions in Sichuan, China, published in the Journal of Psychiatric Research.1

The 3 main cluster symptoms of PTSD include re-experiencing, avoidance, and hyperarousal, and many patients also experience the associated symptoms of depression and anxiety. The novel technology of rTMS allows the noninvasive modulation of cortical and subcortical brain excitability that produces these symptoms via repeated alterations of the coil's magnetic field. The area of the brain affected is determined by the frequency used.

Approximately one-third of patients diagnosed with PTSD do not respond well to standard interventions, such as trauma-focused cognitive behavioral therapy (CBT), trauma-focused exposure therapy, stress management techniques, individual therapies (supportive therapy, non-directive counseling, psychodynamic therapy and hypnotherapy), group CBT, eye movement desensitization, and reprocessing therapy. 2-4

The efficacy of active rTMS for PTSD has been demonstrated, but the effect of different frequencies had not previously been evaluated. The study investigators  undertook a meta-analysis and systematic review that included data from 9 literature databases and other sources that yielded 11 relevant studies5-15 that included rTMS findings in 377 participants (217 on active therapy, 160 on sham-treatment) from the date of the creation of each database to August 1, 2016.

Active rTMS significantly reduced total PTSD scores including cluster symptoms as well as associated symptoms of depression and anxiety compared with pretreatment. High-frequency (HF) rTMS results were similar to active rTMS for all symptoms (HF PTSD total score: pooled standardized mean difference [SMD] 3.24; CI, 2.24-4.25), except for anxiety, which did not show a significant treatment effect.

More limited evidence indicated that low-frequency (LF) rTMS also improved total PTSD (total score: pooled SMD +0.92; CI, 0.11-1.72) and depression scores (pooled SMD 0.54; CI, 0.08-1.00) compared with pretreatment levels, but, again, not anxiety.

The investigators found it problematic that both HF and LF rTMS treatments would demonstrate similar effects in reducing total PTSD scores, as previous studies have shown that cortical excitability associated with different PTSD symptoms is increased by HF stimulation and reduced by LF stimulation.16-19 “By more carefully studying the DSM-IV and now its fifth edition (DSM-V), we may generate some new ideas to explain this problem,” they wrote.

The 3 symptom clusters of PTSD from the DSM-IV have been redefined in the DSM-V and now include re-experiencing, avoidance, negative cognition and mood, and hyperarousal, which, the researchers suggested, “might be caused by different pathological mechanisms.” Sorting through the existing evidence using changing criteria posed obvious problems that would be resolved by continued study of both HF and LF rTMS treatments, both alone and comparatively, they concluded.

References

  1. Yan T, Xie Q, Zheng Z, et al. Different frequency repetitive transcanial magnetic stimulation (rTMS) for posttraumatic stress disorder (PTSD): a systematic review and meta-analysis [published online February 7, 2017]. J Psychiatric Res. doi:10.1016/j.jpsychires.2017.02.021
  2. Bisson J, Andrew M. Psychological treatment of post-traumatic stress disorder (PTSD). Cochrane Database Syst Rev. 2007 18;(3):CD003388.
  3. Kessler RC, Sonnega A, Bromet E, et al. Posttraumatic stress disorder in the national comorbidity survey. Arch Gen Psychiatry 1995;52:1048-1060.
  4. Stein DJ, Ipser JC, Seedat S. Pharmacotherapy for post traumatic stress disorder (PTSD). Cochrane Database Syst Rev. 2006 January 24;(1):CD002795.
  5. Bie HX, Wang XY. Effectiveness of high-frequency repetitive transcranial magnetic stimulation as an augmention in posttraumatic stress disorder. J Guangdong Med (Chin. ed.) 2011;32:222-223.
  6. Boggio PS, Rocha M, Oliveiro M, et al. Noninvasive brain stimulation with high-frequency and low-intensity repetitive transcranial magnetic stimulation treatment for posttraumatic stress disorder. J Clin Psychiatry 2010;71(8):992-999. doi:10.4088/JCP.08m04638blu
  7. Cohen H, Kaplan Z, Kotler M, et al. Repetitive transcranial magnetic stimulation of the right dorsolateral prefrontal cortex in posttraumatic stress disorder: a double-blind, placebo-controlled study. Am J Psychiatry. 2004;161:515-524.
  8. Huang X, Wang JL. Research on the therapeutic effects of high frequency repetitive transcranial magnetic stimulation to post-traumatic stress disorder and its related mechanisms. Chin. Ed. Hebei Med. Univ, Shijiazhuang. 
  9. Oznur T,  Akarsu S, Celik C et al.  Is transcranial magnetic stimulation effective in treatment-resistant combat related posttraumatic stress disorder? J Neurosci .2014:19;29-32.
  10. Rosenberg PB, Mehndiratta RB,  Mehndiratta YP, et al. Repetitive transcranial magnetic stimulation treatment of comorbid posttraumatic stress disorder and major depression. J Neuropsychiatry Clin Neurosci. 2002:14:270-276.
  11. Wang Y, Peng L, Zhou XL, et al. Effect of repetitive transcranial magnetic stimulation on core symptoms, positive and negative affects and resilience in rehabilitation patients with post-traumaticstress disorder after traumatic injury. J Third Mil Med (Univ Chin ed.) 2015;37:1571-1575.
  12. Watts BV, Landon B, Groft A, et al. A sham controlled study of repetitive transcranial magnetic stimulation for posttraumatic stress disorder. Brain Stimul 2012;5(1):38-43.  doi:10.1016/j.brs.2011.02.002.
  13. Wu HL, Zao YQ, Hou YH, et al. Acupuncture combined with repetitive transcranial magnetic stimulation in the treatment of post-traumatic stress disorder. J Brain Nerv Dis (Chin. ed.) 2013;21:245-247.
  14. Wu WJ, Peng ZW, Zhang RG et al. Effects of high-frequency repetitive transcranial magnetic stimulation combined with paroxetine in treatment of postdtraumatic stress disorder. J Neurosci Ment Health (Chin ed.) 2014;14:450-453.
  15. Zhou P, Zhang Y, Tan QR. Effect of repetitive transcranial magnetic stimulation (rTMS) combined with paroxetine in the treatment of posttraumatic stress disorder. J Psychiatry (Chin ed.) 2016;29:89-92.
  16. Osuch EA, Benson BE, Luckenbaugh DA, et al. Repetitive TMS combined with exposure therapy for PTSD: a preliminary study [published online March 28, 2008]. J Anxiety Disord 2009; doi: 10.1016/j.janxdis.2008.03.015.
  17. Tillman GD, Kimbrell TA, Calley CS, et al. Repetitive transcranial magnetic stimulation and threat memory: selective reduction of combat threat memory p300 response after right frontal-lobe stimulation. J Neuropsychiatry Clin Neurosci. 2011;23(1):54-59. doi: 0.1176/appi.neuropsych.23.1.40.
  18. Shin LJ, Handwerger K. Is posttraumatic stress disorder a stress-induced fear circuitry disorder? J Trauma Stress 2009;22:409-415.
  19. Simmons A, Matthews SC, Stein MB, et al. Anticipation of emotionally aversive visual stimuli activates right insula. Neuroreport  2004;15:2261-2265.
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