Cholinesterase inhibitors for co-morbid Alzhemer’s disease dementia and schizophrenia: Systematic review and meta-analysis

Cholinergic dysfunction is common to Alzheimer’s dementia and Schizophrenia. The objective of this study is to undertake a systematic review and metaanalysis of the literature on the cognitive and clinical effects of cholinesterase inhibitors administered to patients with schizophrenia and co-morbid Alzheimer’s disease dementia. A literature search of the MEDLINE, CINAHL, PubMed, PsycINFO, EMBASE, AMED, BNI, HMIC and Health Business Elite databases has been performed (up to January 2013) to investigate the use of cholinesterase inhibitors in patients with schizophrenia and dementia. The terms “schizophrenia”, “dementia”, “rivastigmine”, “donepezil”, “galantamine” and “cognitive deficit” have been searched, with a restriction for English language. Five published studies including 1 RCT have been included for the qualitative review. Treatments include Donepezil 5 mg and 10 mg as well as Rivastigmine 9 mg. The numbers of participants vary from 2 in case report to 20 in the RCT. Only 1 study qualifies for meta-analysis. There is a very limited evidence on the efficacy and safety of using acetylcholinesterase inhibitors in the management of dementia co-morbid with schizophrenia. The only randomised controlled study shows lack of evidence in terms of efficacy in using cholinesterase inhibitors in the management of dementia with schizophrenia. Future research projects will have to look at an adequate sample size to explore treatment on various cognitive and noncognitive domains and the sample should be selected by using definitive and internationally acceptable diagnostic criteria.