Predictors of Diagnostic Delay in Amyotrophic Lateral Sclerosis: a Cohort Study Based on Administrative and Electronic Medical Records Data

: To characterize the timing and pathway of amyotrophic lateral sclerosis (ALS) diagnosis and to identify predictors of delayed diagnosis in a retrospective cohort. : The cohort included all patients with incident ALS between 2010 and 2014 in Friuli-Venezia Giulia (FVG) region, Italy, admitted to two University Hospitals. Information on demographics, clinical presentation, and healthcare use was obtained from health databases and electronic medical records (EMRs). Total diagnostic time (TDT), the interval between ALS symptoms onset and diagnosis, was compared between patient groups through Wilcoxon-Mann-Whitney test. The adjusted odds ratio (aOR), with 95% confidence interval (95% CI), of having a TDT ≥12 months was estimated using unconditional logistic regression. : Among 134 patients, median TDT (interquartile range [IQR]) was 11.5 months (7.1-18.3), shorter in those aged <60 years vs. ≥60 years (8.1; 5.1-11.1 vs. 12.4; 7.4-21.5;  = 0.0064), first referred to a neurologist vs. other specialist (10.2; 6.1-16.3 vs. 13.2; 8.1-24.5;  = 0.0386) and without neurologic comorbidities (11.1; 7.1-16.5 vs. 19.7; 8.8-33.7;  = 0.0243). TDT was ≥12 months in 64 (48.5%) patients and was predicted by male sex (aOR: 2.47; 95% CI: 1.06-5.75), age at onset ≥60 years (11.46; 3.13-41.9), spinal onset (2.04; 1.00-5.93), and prior therapies or first referral to a non-neurologist (3.15; 1.36-7.29). : In this cohort, delayed diagnosis was common, particularly in older patients and in those with neurological comorbidities. Timely referral to a neurologist may improve diagnostic timing.