Table 1.
Characteristics of the included systematic reviews.
| Included studies | No. of RCTs | Participants | Experimental intervention | Control intervention | Basic features of rTMS | Risk assessment tools | Meta-analyses | Adverse effects | Follow up | Disease type | Outcomes | Main conclusion |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cheng and Wu (2016) | 9 | 258 | rTMS, rTMS + routine treatment | Sham stimulation, sham stimulation + routine treatment | 5/10/20 HZ, left DLPFC/bilateral DLPFC | Cochrane risk of bias tool | Yes | None | Not reported | Not reported | PNTS, NPI, ADAS-cog | High-frequency rTMS has a significant improvement effect on the cognitive function of patients with AD. Correct use of stimulation therapy can achieve significant efficacy. Moreover, the therapy is painless, non-invasive, simple and easy to operate, and is an ideal method for the treatment of AD |
| Dong et al. (2018) | 5 | 148 | rTMS, rTMS + routine treatment | Sham stimulation, sham stimulation + routine treatment | 10/20 HZ, left DLPFC/bilateral DLPFC/Broca/Wernicke/pSAC, 80–110% RMT | Cochrane risk of bias tool | Yes | Mild extrapyramidal reaction, headache | 1 to 3 months | Not reported | ADAS-cog, MMSE, GDS scale, CGIC scale, IADL scale | rTMS is relatively well tolerated, with some promise for cognitive improvement and global impression inpatients with AD. Our findings also indicate the variability between ADAS-cog and MMSE in evaluating global cognitive impairment |
| Liang et al. (2017) | 5 | 223 | rTMS, rTMS + routine treatment | Sham stimulation, sham stimulation + routine treatment | 1/10/20 HZ, left DLPFC/bilateral DLPFC | Cochrane risk of bias tool | Yes | Not reported | Not reported | Moderate/late AD | ADAS-cog, MMSE | Transcranial magnetic stimulation has significant therapeutic effect on cognitive function in AD. High frequency stimulation is significantly effective compared to the low frequency stimulation |
| Liao et al. (2015) | 7 | 94 | rTMS, rTMS + routine treatment | Sham stimulation, sham stimulation + routine treatment | 1/10/20 HZ, left DLPFC/bilateral DLPFC/right DLPFC | Cochrane risk of bias tool | Yes | Not reported | Not reported | Mild/moderate AD | MMSE | This meta-analysis supports the notion that rTMS has a therapeutic effect on the cognition of AD patients with mild to moderate cognitive impairment. High frequency rTMS, but not low frequency rTMS, over the right DLPFC and/or bilateral DLPFC appears to be more effective in this regard |
| Lin et al. (2019) | 12 | 231 | rTMS, rTMS + routine treatment | Sham stimulation, sham stimulation + routine treatment | 1/5/10/20 HZ, left DLPFC/bilateral DLPFC/Broca/Wernicke/pSAC/IFG/STG, 90–110% RMT, 1–20 Hz | Cochrane risk of bias tool | Yes | Not reported | Not reported | Not reported | MMSE | rTMS can significantly improve cognitive ability in patients with mild to moderate AD. Stimulation of multiple sites and long-term treatment are better at improving AD-associated cognitive performance |
| Wang et al. (2020) | 10 | 240 | rTMS, rTMS + routine treatment | Sham stimulation, sham stimulation + routine treatment | 10/20 HZ, left DLPFC/bilateral DLPFC/Broca/Wernicke/pSAC/IFG/STG, 80–110% RMT | Cochrane risk of bias tool | Yes | Mild extrapyramidal reactions, transient headache, fatigability and painful scalp sensation | Not reported | Not reported | MMSE | rTMS was an effective therapy for cognitive impairment in AD |
| Xiu et al. (2024) | 12 | 1,161 | rTMS, rTMS + routine treatment | Sham stimulation, sham stimulation + routine treatment | 5/10/15/20 HZ, left DLPFC/bilateral DLPFC, 80–120% RMT | Cochrane risk of bias tool | Yes | Scalp pain, loss of consciousness, cerebellar embolism, headache, tinnitus, fatigue and stimulation of regional muscle contraction | Not reported | Not reported | MMSE, MoCA, ADAS-Cog, P300 | High-frequency rTMS can improve global cognitive function in elderly patients with mild to moderate AD, which is an effective and safe rehabilitation treatment tool for AD patients |
| Zhang et al. (2022) | 9 | 361 | rTMS, rTMS + routine treatment | Sham stimulation, sham stimulation + routine treatment | 1/10/20 HZ, left DLPFC/bilateral DLPFC/Broca/Wernicke/pSAC/IFG/STG, 80–120% RMT | Cochrane risk of bias tool | Yes | Headache, fatigue | 1 to 3 months | Mild/moderate AD | ADAS-cog, MMSE | rTMS is a potentially effective treatment for cognitive impairment in AD that is safe and can induce long-lasting effects |
AD, Alzheimer’s disease; rTMS, repetitive transcranial magnetic stimulation; RMT, resting motor threshold; DLPFC, dorsolateral prefrontal cortex; IFG, inferior frontal gyrus; STG, superior temporal gyrus; pSAC, parietal somatosensory association cortex; PNTS, picture naming test score; NPI, neuropsychiatric inventory; ADAS-cog, Alzheimer disease assessment cognitive scale; MMSE, Mini-Mental State Examination; IADL, instrumental daily living activity; GDS, geriatric depression scale; CGIC, Clinician’s global impression of change.