P2‐248: Neuropsychological and MRI Findings in MAPT Mutation Carriers in the Evolution from the Asymptomatic to Symptomatic State
Year: 2016
Type: article
Study design: Case Report
Abstract: It is important to characterize the cognitive and imaging features in familial frontotemporal dementia (fFTD) from the asymptomatic to symptomatic state in order to plan for future disease-modifying trials. We identified all asymptomatic members of kindreds with a MAPTmutation who have been followed annually with cognitive measures and high resolution 3D T1-weighted MRI scans, and became symptomatic. Cognitive measures included Boston Naming Test (BNT), Category Fluency (CF), Trailmaking Test (TMT) A and B and WAIS-R Digit Symbol Total Score (DS). The Symmetric Diffeomorphic Image Normalization method was used to obtain Tensor Based Morphometry (TBM-SyN) maps on MRI to measure volume changes in frontal (FV), temporal (TV) and frontotemporal (FTV) regions. Annualized rates of change (i.e., slope estimates) were calculated using least squares from a linear regression model, with slope estimates different from 0 (with p<0.05) considered statistically significant. 3 subjects who had the N279K mutation were identified. Key features were as follows: Case 1 (male)-initial exam age 36, onset age 39, current age 42; Case 2 (male)- initial exam age 39, onset age 44, current age 48; Case 3 (female)-initial exam age 41, onset age 48, current age 49. The most robust slope estimates for all 3 patients were in TV, FV and FTV (each p<0.01), with at least 2 patients showing statistically significant changes in BNT, CF, TMTA and DS. Structural MRI changes preceded symptom onset in each patient, whereas neuropsychological performance was more variable. These findings suggest that changes in frontal and temporal volume on MRI precede symptom onset, and more consistently track the evolution from the asymptomatic to symptomatic state in MAPT mutation carriers than traditional neuropsychological measures.
Source: Alzheimer s & Dementia
Institutions: Mayo Clinic, Mayo Clinic in Florida
Language: English
Subfield: Psychiatry and Mental health
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2533175030