Cognitive function and psychiatric symptoms in early- and late-onset frontotemporal dementia

Some recent studies mentioned that late-onset frontotemporal dementia (FTD) is more common than previously assumed. Although much research has been done in the field, there are no systematic studies which have compared clinical characteristics of early- and late-onset FTD. The aim of this study was to compare cognitive function and psychiatric symptoms in patients with early- and late-onset FTD.

Study participants were consecutive outpatients. There were 35 FTD patients; their mean age at onset was 63.0 years. We studied sex, education, duration from onset to consultation, Clinical Dementia Rating (CDR) scores, Mini-Mental State Examination (MMSE) scores, Raven's Coloured Progressive Matrices (RCPM) scores, and Neuropsychiatric Inventory (NPI) scores at first consultation of early- and late-onset FTD patients.

There were no significant differences in sex ratio, education, CDR scores, and duration from onset to consultation. There were significant differences in the total MMSE scores, 'three-word recall task', 'construction task', and RCPM scores; late-onset groups scored significantly lower than early-onset groups. There were significant differences in the apathy domain of NPI and total NPI scores; late-onset groups scored significantly higher than early-onset groups.

Late-onset FTD patients may have memory and visuospatial deficits in addition to their behavioural changes, even if they are clinically diagnosed according to consensus diagnostic criteria. They also present more apathy, and they may have a different histolopathological background.