Time to diagnosis and its predictors in syndromes associated with Frontotemporal Lobar Degeneration

Objectives Frontotemporal Lobar Degeneration (FTLD) causes a heterogeneous group of neurodegenerative disorders with a wide range of clinical features. This might delay time to diagnosis. The aim of the present study is to establish time to diagnosis and its predictors in patients with FTLD-associated syndromes. Design Retrospective study. Setting Tertiary referral center. Participants A total of 1029 patients with FTLD-associated syndromes (age: 68 [61-73] years, females: 46%) from 1999 to 2023 were included in the present study. Measurements Time to diagnosis was operationalized as the time between symptom onset and the diagnosis of a FTLD-associated syndrome. The associations between time to diagnosis and possible predictors (demographic and clinical variables) were investigated through univariate and multivariate linear models. Results Median time to diagnosis was 2 [1], [2], [3] years. We observed that younger age at onset (β=-0.03, p<0.001), having worked as a professional rather than as a blue (β=0.52, p=0.024) or a white (β=0.46, p=0.050) collar, and having progressive supranuclear palsy (p<0.05) or the semantic variant of primary progressive aphasia (p<0.05) phenotypes were significantly associated with increased time to diagnosis. No significant changes of time to diagnosis have been observed over 20 years. Conclusions The identification of predictors of time to diagnosis might improve current diagnostic algorithms, resulting in a timely initiation of symptomatic treatments, early involvement in clinical trials, and more adequate public health policies for patients and their families.