Our aim was to investigate demographic, clinical and genetic survival factors in a Tunisian cohort with atypical parkinsonian syndromes (APS).

APS encompass a spectrum of neurodegenerative diseases including dementia with Lewy bodies (DLB), progressive supranuclear palsy (PSP), multiple system atrophy (MSA), and corticobasal syndrome (CBS), all characterized by faster progression and earlier mortality compared to Parkinson’s disease. However, the predictors of survival are still controversial.

We conducted a retrospective study over a period of 19 years (2003-2021) in the Department of Neurology of Razi University Hospital, in Tunis, Tunisia, including patients diagnosed with APS. Survival was explored using Kaplan-Meier analysis. Demographic, clinical, neuropsychological features and frequency of Apolipoprotein Epsilon 4 (ApoE?4) allele were analyzed in the survival analysis.

We included 340 APS patients (151 DLB, 74 PSP, 70 MSA, 45 CBS). Median survival was 6 years from disease onset in DLB and MSA and 7 years in PSP and CBS. It was significantly shorter for men (p=0.005) and for patients with memory symptoms at onset (p=0.040) in DLB, later age of onset (>65 years, p=0.021), earlier dysphagia and ApoE?4 allele carrying status in PSP patients. In MSA, median survival was shorter in parkinsonian subtype (MSA-P) compared to cerebellar subtype (MSA-C) in patients having urinary dysfunction. Although the presence of stridor was associated with shorter survival (6 vs 9 years), the difference was not statistically significant (p=0.090). In CBS, the presence of alien limb syndrome (p=0.031), dementia (p=0.026) and tremor-dominant parkinsonian syndrome (p=0.019) were associated with shorter survival.

Our results showed shorter survival in synucleinopathies compared to tauopathies with different predictive demographic and clinical factors across APS. ApoE?4 seemed to have an effect only in PSP. Larger prospective studies are needed to better investigate the various survival determinants.