Alhwaishel Khaled, Gallo Ruelas Mariano, Ahmed Aisha Rizwan, Soares Victor Gonçalves, Koppanatham Aishwarya, Bocanegra-Becerra Jhon E, Weba Elizabet Taylor Pimenta, Punukollu Anuraag, Kuhar Krish, de Moraes Mangas Gabriel, de Oliveira Jéssica Sales, Aldubaisy Reem Ali, Franklin Brodus A, Dos Santos Mancilha Murilo, João Rafael B
Mansoura Manchester Program, Faculty of Medicine, Mansoura University, Mansoura, Egypt.
Instituto de Investigación Nutricional (IIN), Lima, Peru.
Neurol Sci. 2025 Aug 26. doi: 10.1007/s10072-025-08344-y.
Primary progressive aphasia (PPA) is a group of dementias characterized by progressive loss of specific language functions with relative sparing of other cognitive domains. Transcranial direct current stimulation (tDCS) has been introduced as a potential therapeutic option for PPA. We aim to evaluate the efficacy of tDCS in improving cognitive and language functions in patients with PPA.
PubMed, Embase, Cochrane Library, and Web of Science were searched up to June 2024 to identify randomized controlled studies (RCTs) comparing tDCS vs sham procedure in patients with PPA.
Our analysis encompassed ten RCTs comparing the efficacy of tDCS against sham treatment, with a total of 167 participants. Due to the crossover design implemented in several studies, 94.5% of participants received active tDCS, while 91.1% received the sham intervention. The findings demonstrated significant improvements immediately post-tDCS (SMD 0.29, 95% CI 0.003-0.57, p = 0.05, I2 = 19%) and sustained benefits after two months or more (SMD 0.51, 95% CI 0.10-0.92, p = 0.01, I2 = 11%) in the untrained naming task. Similarly, for the trained naming tasks, significant improvement was observed (SMD 0.96; 95% CI 0.27 to 1.65; p < 0.01; I2 = 0%), even after the end of the tDCS treatment, with effects persisting for up to two months. (SMD 0.64; 95% CI 0.15 to 1.13; p = 0.01; I2 = 8%). However, no significant improvements were observed in cognitive tasks, untrained comprehension, language, and trained semantic tasks.
Our findings suggest that tDCS may be efficacious in augmenting naming tasks both acutely and over a prolonged period of up to two months. However, its effects on overall cognitive performance remain inconclusive. Further robust trials are warranted to elucidate its impact on cognitive function.
原发性进行性失语（PPA）是一组痴呆症，其特征是特定语言功能逐渐丧失，而其他认知领域相对保留。经颅直流电刺激（tDCS）已被引入作为PPA的一种潜在治疗选择。我们旨在评估tDCS对改善PPA患者认知和语言功能的疗效。
检索截至2024年6月的PubMed、Embase、Cochrane图书馆和Web of Science，以确定比较tDCS与假手术治疗PPA患者的随机对照试验（RCT）。
我们的分析纳入了10项比较tDCS与假手术治疗疗效的RCT，共有167名参与者。由于几项研究采用了交叉设计，94.5%的参与者接受了活性tDCS，而91.1%的参与者接受了假干预。结果表明，在未经训练的命名任务中，tDCS后立即有显著改善（标准化均数差[SMD]0.29，95%置信区间[CI]0.003 - 0.57，p = 0.05，I² = 19%），两个月或更长时间后仍有持续益处（SMD 0.51，95% CI 0.10 - 0.92，p = 0.01，I² = 11%）。同样，对于经过训练的命名任务，即使在tDCS治疗结束后也观察到显著改善（SMD 0.96；95% CI 0.27至1.65；p < 0.01；I² = 0%），效果持续长达两个月（SMD 0.64；95% CI 0.15至1.13；p = 0.01；I² = 8%）。然而，在认知任务、未经训练的理解、语言和经过训练的语义任务中未观察到显著改善。
我们的研究结果表明，tDCS可能在急性和长达两个月的延长期间增强命名任务方面有效。然而，其对整体认知表现的影响仍不确定。需要进一步进行有力的试验来阐明其对认知功能的影响。
