Dataset Information

Tolerability and blinding of 4x1 high-definition transcranial direct current stimulation (HD-tDCS) at two and three milliamps.

ABSTRACT: BACKGROUND:Transcranial direct current stimulation (tDCS) is an in-demand form of neuromodulation generally regarded as safe and well tolerated. However, few studies have examined the safety, tolerability, or blinding of High Definition (HD-) tDCS, especially in older adults and at stimulation intensities of 2 milliamps (mA) or greater. OBJECTIVE:We examined the rates of serious adverse events and common side effects to establish safety and tolerability, respectively, in HD-tDCS. Blinding was evaluated using participants' accuracy in correctly stating their condition (i.e., active or sham). METHODS:The sample included 101 older adults (Mage?=?69.69, SD?=?8.33; Meduc?=?16.27, SD?=?2.42) who participated in our double blind randomized controlled studies or in case studies that used HD-tDCS for 20-30?min at 2?mA (n?=?66, 31 active) or 3?mA (n?=?35, 20 active). Participants completed a standardized side effect questionnaire and were asked whether they received active or sham stimulation at the end of each session. RESULTS:There were no serious adverse events and no participants withdrew, suggesting that HD-tDCS meets basic safety parameters. Tolerability was comparable between active and sham HD-tDCS regardless of intensity (2?mA and 3?mA) in first session (allp?>?.09). Tingling was the most commonly endorsed item (59% active; 56% sham) followed by burning sensation (51% active; 50% sham), the majority of which were mild in nature. "Severe" ratings were reported in fewer than 4% of sessions. Blinding appeared adequate since there were no significant group differences between individuals correctly stating their stimulation condition (?2?=?0.689, p?=?.679). The above tolerability and blinding findings generally persisted when multiple session data (i.e., 186 total sessions) were considered. CONCLUSIONS:HD-tDCS appears well-tolerated and safe with effective sham-control in older adults, even at 3?mA. These data support the use of HD-tDCS in randomized controlled trials and clinical translation efforts.

SUBMITTER: Reckow J

PROVIDER: S-EPMC6512313 | biostudies-literature | 2018 Sep - Oct

REPOSITORIES: biostudies-literature

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Tolerability and blinding of 4x1 high-definition transcranial direct current stimulation (HD-tDCS) at two and three milliamps.

Reckow Jaclyn J Rahman-Filipiak Annalise A Garcia Sarah S Schlaefflin Stephen S Calhoun Oliver O DaSilva Alexandre F AF Bikson Marom M Hampstead Benjamin M BM

Brain stimulation 20180504 5

<h4>Background</h4>Transcranial direct current stimulation (tDCS) is an in-demand form of neuromodulation generally regarded as safe and well tolerated. However, few studies have examined the safety, tolerability, or blinding of High Definition (HD-) tDCS, especially in older adults and at stimulation intensities of 2 milliamps (mA) or greater.<h4>Objective</h4>We examined the rates of serious adverse events and common side effects to establish safety and tolerability, respectively, in HD-tDCS. ...[more]

PMID: 29784589

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Project description:BACKGROUND:Chronic tinnitus is a highly prevalent symptom, with many patients reporting considerable effects of tinnitus on quality of life. No clear evidence-based treatment options are currently available. While counseling-based methods are valuable in some cases, they are not sufficiently effective for all tinnitus patients. Neuromodulation techniques such as high-definition transcranial direct current stimulation (HD-tDCS) are proposed to have positive effects on tinnitus severity but, to date, these effects have not been proven conclusively. The proposed trial will investigate the hypothesis that chronic tinnitus patients receiving HD-tDCS will report a positive effect on the impact of tinnitus on daily life, as compared to patients receiving sham stimulation. METHODS:This study proposes a randomized, double-blind, placebo-controlled trial with parallel group design. A total of 100 chronic tinnitus patients will be randomly allocated to an experimental group or a sham group, with allocation stratified according to gender and tinnitus severity. Patient and researcher will be blinded to the patient's allocation. Patients will undergo six sessions of sequential dual-site HD-tDCS of the left temporal area and the right dorsolateral prefrontal cortex. Evaluations will take place at baseline, immediately following treatment, and at three and six months after the start of the therapy. The primary outcome measure is the change in Tinnitus Functional Index (TFI) score. Secondary outcome measures include audiological measurements, cortical auditory evoked potentials, the Repeatable Battery for the Assessment of Neuropsychological Status adjusted for hearing-impaired individuals (RBANS-H), and supplementary questionnaires probing tinnitus severity and additional symptoms. By use of a linear regression model, the effects of HD-tDCS compared to sham stimulation will be assessed. DISCUSSION:The objective of this study is to evaluate whether HD-tDCS can reduce the impact of tinnitus on daily life in chronic tinnitus patients. To date, published trials on the effects of HD-tDCS on tinnitus suffer from a lack of standardization and few randomized controlled trials exist. The proposed study will be the first adequately powered trial to investigate the effects of sequential dual-site HD-tDCS on tinnitus severity. TRIAL REGISTRATION:ClinicalTrials.gov, NCT03754127 . Registered on 22 November 2018.

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Dataset Information

Tolerability and blinding of 4x1 high-definition transcranial direct current stimulation (HD-tDCS) at two and three milliamps.

Publications

Tolerability and blinding of 4x1 high-definition transcranial direct current stimulation (HD-tDCS) at two and three milliamps.

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