This systematic review and meta-analysis looked at transcranial direct current stimulation, or tDCS, for patients with Alzheimer's disease and mild cognitive impairment. The researchers combined data from multiple studies involving a total of 616 people to see if this treatment helped cognitive function.
The analysis found that tDCS significantly improved global cognition, measured by standard tests like the MMSE and MoCA. It also showed a significant but preliminary effect on visuospatial ability. However, the study did not find a significant effect on executive function, and results for attention were described as having a small effect.
No adverse events or safety concerns were reported in the included studies. The authors note that evidence for other cognitive domains was limited and findings for attention and executive function remain inconclusive. They suggest that future studies should use more comprehensive testing batteries in larger trials to confirm these results.