In adults at risk of frontotemporal dementia, structural imaging and cognitive changes can be identified 5 to 10 years before the expected onset of symptoms, according to a multicenter neuroimaging study of subjects with and without genetic mutations associated with dementia.
The study population included 118 patients with a pathogenic mutation in one of three genes (GRN, MAPT, or C9orf72), of whom 40 were symptomatic and 78 were asymptomatic, and 102 non-carriers.
Imaging differences between carriers and non-carriers were first evident 10-years prior to expected onset of dementia, with reductions in the insula and temporal lobe.
Neuropsychological differences were first evident 5 years prior to expected onset, with significant differences in all measures but immediate recall and verbal fluency.
Citation: Rohrer JD, Nicholas JM, Cash DM, et al. Presymptomatic cognitive and neuroanatomical changes in genetic frontotemporal dementia in the Genetic Frontotemporal Dementia Initiative (GENFI) study: a cross-sectional analysis. Lancet Neurol. 2015;14(3):253-262. doi: 10.1016/S1474-4422(14)70324-2.