Early onset but long survival and other prognostic factors in Chinese sporadic amyotrophic lateral sclerosis

Objectives: To explore the cause of long survival but early onset and other prognostic factors among Chinese sporadic amyotrophic lateral sclerosis (ALS) patients. Methods: Patients with ALS were recruited and followed up from Jan 2013 to Jan 2017. Phenotype and survival were compared among different age-at-onset groups. Candidate prognostic factors were analyzed by Kaplan-Meier method, Cox regression and Royston Parmar (RP) model dealing with breaches of proportional hazard assumption. Results: In the cohort of 531 patients. mean age-at-onset was 53.68 years (SD:10.85) and overall estimated median survival time was 59 months (95% CI: 48.29-69.71). Pairwise comparison showed that patients above 65 years at onset were more frequently bulbar onset (adjusted residual: 3.0), less frequently lumbosacral onset (adjusted residual: -3.0), and had shorter survival compared with other age groups (p = 0.002). Cox and RP model demonstrated independent prognostic variables including age at onset, bulbar onset, diagnostic delay, MRC-score at first diagnosis and region of residence. Conclusions: This clinic-based study suggested that Chinese sporadic ALS patients had relatively long survival probably due to young age and less bulbar onset cases. Short diagnostic delay, low MRC-score and northern residence were also predicative of short survival. Reallocation of resources is needed to optimize quality care and prolong survival time. (C) 2019 Elsevier Ltd. All rights reserved.