Efficacy of Acetylcholinesterase Inhibitors in the Logopenic Variant of Primary Progressive Aphasia

Introduction: For over 25 years, cholinesterase inhibitors (ChEIs) have been the main symptomatic treatment for Alzheimer's disease (AD). Several meta-analyses have supported their effectiveness in various neurocognitive, functional, and behavioral aspects of amnestic AD. Over 86% of cases of the logopenic variant of primary progressive aphasia (lvPPA), also named language variant AD, are caused by a similar pathologic process than AD, yet no study has examined the efficacy of ChEIs in this AD variant. We aimed to explore the efficacy of ChEIs in the treatment of lvPPA by comparing their evolution on the MMSE, and other functional and behavioral parameters, to that of treated amnestic AD patients. Methods: A retrospective chart review was performed in 45 patients with lvPPA and 52 patients with amnestic AD. Both groups were similar in terms of age, level of education, and onset of symptoms. Drug history and MMSE scores, as well as functional (activities of daily living [ADLs] and instrumental activities of daily living [IADLs]), neurocognitive and neuropsychiatric symptoms were collected on several time points before and after the introduction of ChEIs. Data were analyzed using ANOVA and a generalized linear mixed model. Results: Patients with lvPPA showed a similar trajectory of decline than amnestic AD patients on serial MMSEs up to 12-24 months after the introduction of ChEIs. There was a significant impact on ADLs but not IADLs and neuropsychiatric symptoms remained stable over time. Conclusion: This study provides preliminary evidence for efficacy of ChEIs in patients with lvPPA and suggests similar benefits to those seen in amnestic AD patients, hence reassuring patients and their physicians.