Clinical and Paraclinical Predictors of Survival in Amyotrophic Lateral Sclerosis: Results from a Three-Year Longitudinal Cohort Study.

Abstract

Background: Amyotrophic Lateral Sclerosis (ALS) is a heterogeneous neurodegenerative disorder with highly variable progression and survival. Identifying early prognostic indicators is essential for patient stratification and management.

Objectives: To evaluate clinical, respiratory, and functional predictors of survival in a prospective cohort of ALS patients over a three-year period.

Methods: A cohort of 44 ALS patients was followed from 2022 to 2025. Demographic and anthropometric characteristics, clinical data including ALS subtypes and phenotypes, site of onset, revised ALS functional rating scale (ALSFRS-R) and subscores, ALSFRS-R progression rate, time to diffusion and generalization, spirometric parameters, and progression patterns were assessed. Survival analysis was performed using Kaplan-Meier estimates and univariate and multivariate Cox proportional hazard regression analysis.

Results: The overall median survival time was 53 months. Univariate Cox regression revealed that older age at onset, shorter diagnostic delay, lower respiratory function, lower vitamin D levels, and rapid vertical progression were associated with reduced survival. Bulbar-onset phenotype and rapid disease progression rate (ΔPR) were significant predictors of mortality. Specific ALSFRS-R subscores also showed prognostic relevance. A longer time to diffusion as well as a longer time to generalization were significantly associated with prolonged survival. Multivariate analysis confirmed the independent prognostic value of ΔPR, time to diagnosis, and ALSFRS-R swallowing and handwriting subscores.

Conclusions: This study supports the prognostic value of previously studied clinical and paraclinical markers in ALS and proposes novel predictors, ALSFRS-R handwriting, and time to diffusion, which require further validation in larger prospective cohorts.