title: Neuroplastic Effects of Transcranial Direct Current Stimulation on Painful Symptoms Reduction in Chronic Hepatitis C: A Phase II Randomized, Double Blind, Sham Controlled Trial.
abstract: BACKGROUND
  Pegylated Interferon Alpha (Peg-IFN) in combination with other drugs is the standard treatment for chronic hepatitis C infection (HCV) and is related to severe painful symptoms. The aim of this study was access the efficacy of transcranial direct current stimulation (tDCS) in controlling the painful symptoms related to Peg-IFN side effects.
  
  
  METHODS
  In this phase II double-blind trial, twenty eight (n = 28) HCV subjects were randomized to receive either 5 consecutive days of active tDCS (n = 14) or sham (n = 14) during 5 consecutive days with anodal stimulation over the primary motor cortex region using 2 mA for 20 min. The primary outcomes were visual analogue scale (VAS) pain and brain-derived neurotrophic factor (BDNF) serum levels. Secondary outcomes were the pressure-pain threshold (PPT), the Brazilian Profile of Chronic Pain: Screen (B-PCP:S), and drug analgesics use.
  
  
  RESULTS
  tDCS reduced the VAS scores (P < 0.003), with a mean pain drop of 56% (p < 0.001). Furthermore, tDCS was able to enhance BDNF levels (p < 0.01). The mean increase was 37.48% in the active group. Finally, tDCS raised PPT (p < 0.001) and reduced the B-PCP:S scores and analgesic use (p < 0.05).
  
  
  CONCLUSIONS
  Five sessions of tDCS were effective in reducing the painful symptoms in HCV patients undergoing Peg-IFN treatment. These findings support the efficacy of tDCS as a promising therapeutic tool to improve the tolerance of the side effects related to the use of Peg-IFN. Future larger studies (phase III and IV trials) are needed to confirm the clinical use of the therapeutic effects of tDCS in such condition.
  
  
  BACKGROUND
  Brazilian Human Health Regulator for Research with the approval number CAAE 07802012.0.0000.5327.
authors.affiliation: Laboratory of Pain and Neuromodulation, Department of Clinical Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul Porto Alegre, Brazil.
authors.forename: Aline P
authors.initials: AP
authors.lastname: Brietzke
authors.affiliation: Laboratory of Pain and Neuromodulation, Department of Clinical Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul Porto Alegre, Brazil.
authors.forename: Joanna R
authors.initials: JR
authors.lastname: Rozisky
authors.affiliation: Laboratory of Pain and Neuromodulation, Department of Clinical Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul Porto Alegre, Brazil.
authors.forename: Jairo A
authors.initials: JA
authors.lastname: Dussan-Sarria
authors.affiliation: Laboratory of Pain and Neuromodulation, Department of Clinical Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul Porto Alegre, Brazil.
authors.forename: Alicia
authors.initials: A
authors.lastname: Deitos
authors.affiliation: Laboratory of Pain and Neuromodulation, Department of Clinical Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul Porto Alegre, Brazil.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Laste
authors.affiliation: Laboratory of Pain and Neuromodulation, Department of Clinical Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul Porto Alegre, Brazil.
authors.forename: Priscila F T
authors.initials: PF
authors.lastname: Hoppe
authors.affiliation: Laboratory of Pain and Neuromodulation, Department of Clinical Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul Porto Alegre, Brazil.
authors.forename: Suzana
authors.initials: S
authors.lastname: Muller
authors.affiliation: Laboratory of Pain and Neuromodulation, Department of Clinical Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul Porto Alegre, Brazil.
authors.forename: Iraci L S
authors.initials: IL
authors.lastname: Torres
authors.affiliation: Department of Internal Medicine (Gastroenterology/Hepatology), Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul Porto Alegre, Brazil.
authors.forename: Mário R
authors.initials: MR
authors.lastname: Alvares-da-Silva
authors.affiliation: Laboratory of Neuromodulation and Center for Clinical Research Learning, Physics and Rehabilitation Department, Spaulding Rehabilitation Hospital Boston, MA, USA.
authors.forename: Rivadavio F B
authors.initials: RF
authors.lastname: de Amorim
authors.affiliation: Laboratory of Neuromodulation and Center for Clinical Research Learning, Physics and Rehabilitation Department, Spaulding Rehabilitation Hospital Boston, MA, USA.
authors.forename: Felipe
authors.initials: F
authors.lastname: Fregni
authors.affiliation: Laboratory of Pain and Neuromodulation, Department of Clinical Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul Porto Alegre, Brazil.
authors.forename: Wolnei
authors.initials: W
authors.lastname: Caumo
keywords: Hepatitis C; Hepatitis C virus; PEG-IFN; chronic pain; transcranial direct current stimulation