Fridriksson J, et al. - Researchers carried out a double-blinded, prospective randomized clinical trial to investigate whether it’s worth it to study anodal transcranial direct current stimulation (A-tDCS) as an adjunctive intervention during speech therapy to improve speech production (naming) for people with long-term poststroke aphasia. This investigation found no evidence that further study of adjunctive A-tDCS would be futile when combined with behavioral aphasia treatment. The findings provide motivation to proceed with another trial to study the impact of A-tDCS on the outcome of aphasia treatment in individuals poststroke.

Methods

• This trial used a futility design to test adjunctive A-tDCS during speech therapy.
• The setting was an outpatient clinic.
• For this investigation, enlistment of people started in August 2012 and was completed in March 2017, and the duration of follow-up was 6 months.
• Analyses started in April 2017.
• Participants were taken from a volunteer sample, and 89 subjects were screened.
• Participants in the study were patients with long-term (> 6 months) aphasia due to 1 previous left hemisphere stroke.
• Patients were matched based on site (University of South Carolina or Medical University of South Carolina), baseline age, type of aphasia, and aphasia severity in comparing A-tDCS and sham tDCS.
• Main intervention was outpatient speech therapy for 3 weeks (15 sessions, 45 minutes each) combined with either A-tDCS vs sham tDCS applied to preserved left temporal lobe regions.
• The ability to name common objects was the primary outcome, assessed twice before and after therapy.

Results

• An aggregate of 74 subjects were enlisted.
• Study participants had a mean (SD) age of 60 (10) years, had 15 (2) years of education, and were 44 (40) months from stroke onset.
• In this analysis, there were 52 men (70%) and 62 non-Hispanic white individuals (84%) and most were retired or not employed (59 [80%]).
• The most common aphasia type (39 [52.7%]) was broca aphasia.
• It was noted that the adjusted mean (SE) change from pretreatment baseline in correct naming was 13.9 (2.4) words (95% CI, 9.0-18.7) for A-tDCS and 8.2 (2.2) words (95% CI, 3.8-12.6) for sham tDCS, with mean (SE) A-tDCS difference of 5.7 (3.3) words (95% CI, -0.9 to 12.3), showing a relative 70% increase in correct naming for A-tDCS relative to sham.
• The futility hypothesis P value was .90, showing failure to reject the null hypothesis, providing no evidence that further study of A-tDCS is futile.
• Findings suggested no association of serious adverse events with A-tDCS.