Low-Frequency Repetitive Transcranial Magnetic Stimulation in Patients With Poststroke Aphasia: Systematic Review and Meta-Analysis of Its Effect Upon Communication

Objective The aim of the study was to investigate the effectiveness and safety of low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) in patients with poststroke aphasia. Method We comprehensively searched for eligible studies from 11 electronic medical databases from their inception to February 20, 2019. Randomized controlled trials reporting the effectiveness of LF-rTMS for patients with poststroke aphasia were included. The primary outcome was language ability. The secondary outcomes were functional communication and adverse events. The methodological quality of the randomized controlled trials was evaluated by the Cochrane Back Review Group Risk of Bias Assessment Criteria. Results Of the 567 records retrieved, 18 studies with a total of 536 participants were included. All the included studies were of relatively acceptable methodological quality. All studies but one used LF-rTMS + speech and language therapy (SLT), not LF-rTMS alone. The meta-analysis showed that LF-rTMS had beneficial effects for patients with aphasia after a stroke in terms of naming, repetition, comprehension, written language, and functional communication. The subgroup analyses of language performance showed positive effects of LF-rTMS among stroke patients with chronic aphasia and acute aphasia. LF-rTMS + SLT had effects on language performance that were superior to the sham rTMS + SLT and SLT alone. A shorter LF-rTMS duration benefited language performance more than a longer duration. Additionally, 20 min of LF-rTMS per session produced a positive effect on language ability for patients with aphasia after a stroke. No adverse events were reported. Conclusions LF-rTMS + SLT is an effective and safe method for patients with poststroke aphasia to improve their language performance. Additionally, the most commonly used LF-rTMS protocol for patients with aphasia after a stroke was 90% of the resting motor threshold 20 min per day, 5 days per week, for 2 weeks.