Five systematic reviews were identified that addressed the clinical effectiveness and safety of electroconvulsive therapy (ECT) in treating older patients with dementia. Due to the paucity and low quality of the primary evidence that was found, caution must be taken in making inferences from the results. The systematic reviews included primarily chart reviews, case series and case reports published between 1975 and 2017. There was considerable heterogeneity in the patient populations, the components of the intervention, and the types of outcomes that were included in the studies. Each of the systematic reviews reported on a subset of the outcomes of interest. Evidence of limited quality and quantity suggested that the impact of ECT on depressive and psychotic symptoms was mixed and the effects were not permanent. There were reports of reductions in the intensity of visual hallucinations, delusions and other neuropsychiatric symptoms in a subset of patients with LBD or DLB, reductions in agitation and aggression in patients with mild to severe dementia, and clinically significant improvement in symptoms of mania and agitation following a short course of ECT and bi-weekly maintenance treatments. The impact on cognition was mixed with three reviews reporting that some patients exhibited symptoms of confusion and other forms of cognitive decline while other patients showed signs of improvement. Data from three reviews suggested that patients relapsed between one week and 5 years of being treated with ECT. Coupled with the mixed and transient responses to ECT were reports of safety issues, ranging from delirium, seizures, stuttering and slurred speech to serious cardiovascular events. It was unclear whether certain events such as spontaneous seizures and confusion could be attributed to treatment or the prevailing condition of the patients. No relevant evidence-based guidelines were found that addressed the use of ECT for the treatment of the behavioural and psychological symptoms of dementia in older adults.