Clinical Manifestations

Sporadic bvFTD is often misdiagnosed as a primary psychiatric disorder (PPD) due to overlapping clinical features and lack of reliable biomarkers. The multi-centre study DIPPA-FTD aims to develop diagnostic- and prognostic-algorithms that can distinguish sporadic bvFTD from late-onset PPD. The aim of the retrospective DIPPA-FTD study was to identify the strongest clinical discriminators. DIPPA-FTD has compiled a retrospective database with 508 sporadic bvFTD and 152 late-onset PPD cases from five cohorts, making it the largest sporadic FTD cohort to date. Logistic regression models and ROC curve analysis were applied to determine discriminative value per clinical marker in separate subsets; (i) neuropsychological features, (ii) visual brain atrophy rating scales and (iii) serum NfL+GFAP. A global (backward stepwise) logistic regression was also conducted in the most optimal subset that had all markers per modality available. All models were adjusted for age, sex and education when indicated. For marker (i) (bvFTD n = 217, PPD n = 75) higher scores of letter fluency (OR:1.47, p