A Systematic Review of Intermittent Theta Burst Stimulation for Neurocognitive Dysfunction in Older Adults with Schizophrenia

Objective: Neurocognitive dysfunction is thought to be one of the core clinical features of schizophrenia, and older adults with schizophrenia exhibited greater overall cognitive deficits than younger adults. The aim of this systematic review was to examine the neurocognitive effects of intermittent theta burst stimulation (iTBS) as an adjunctive treatment for older adults suffering from schizophrenia. Methods: Randomized double-blinded controlled trials (RCTs) investigating the neurocognitive effects of adjunctive active iTBS versus sham iTBS in older adults with schizophrenia were systematically identified by independent investigators searching Chinese and English databases. Results: Two double-blinded RCTs (n = 132) compared the neurocognitive effects of adjunctive active iTBS (n = 66) versus sham iTBS (n = 66) in patients that fulfilled the inclusion criteria of this systematic review and were analyzed. One RCT found significant superiority of active iTBS over sham iTBS in improving neurocognitive performance in older adults with schizophrenia. In the other RCT, the findings on the neurocognitive effects of iTBS as measured by three different measurement tools were inconsistent. The dropout rate was reported in the two RCTs, ranging from 3.8% (3/80) to 7.7% (4/52). Conclusion: There is preliminary evidence that adjunctive iTBS may have some beneficial effects in the treatment of neurocognitive function in older patients with schizophrenia. Future RCTs with larger sample sizes focusing on the neurocognitive effects of adjunctive iTBS in older adults with schizophrenia are warranted to verify these findings.