Amyotrophic Lateral Sclerosis Survival Score (ALS-SS): A simple scoring system for early prediction of patient survival

Abstract

Our objectives were: (1) to identify independent prognostic factors to determine a survival score for amyotrophic lateral sclerosis (ALS) in a cohort of patients followed in the NEMO Centre (NEuroMuscular Omnicentre); (2) to replicate results in an independent cohort obtained from the Pooled Resource Open Access ALS Clinical Trial Consortium (PRO-ACT) database. Samples were collected from 428 ALS patients from the NEMO database and 2481 patients from the PRO-ACT database. Study design was a retrospective analysis with clinical and biochemical variables, using univariable and multivariable Cox models of analysis. Results showed that, in multivariable analysis, age at diagnosis, diagnostic delay, ALSFRS-R total score, Body Mass Index, aspartate aminotransferase and creatinine level were independently related to survival. These factors were recoded as categorical variables assigning a score from 5 to 15, and the sums of these scores were used to obtain the ALS-Survival Score (ALS-SS). This then allowed to identify three groups having different survival curves. The ALS-SS results were also replicated using data from the PRO-ACT database. In conclusion, considering independent prognostic factors, we were able to give an estimate of survival in our cohort of ALS patients. Whether this ALS-SS may be useful in clinical practice, and potentially in clinical trials, will have to be determined prospectively.

Key words:

• Amyotrophic lateral sclerosis
• survival
• prognosis
• creatinine

Acknowledgements

We thank our patients and their caregivers for their support to our study. We are grateful to Pooled Resource Open-Access ALS Clinical Trials (PRO-ACT) database for data used in the preparation of this article. As such, the following organizations and individuals within the PRO-ACT Consortium contributed to the design and implementation of the PRO-ACT database and/or provided data, but did not participate in the analysis of the data or the writing of this report: Neurological Clinical Research Institute, MGH; Northeast ALS Consortium; Novartis; Prize4Life; Regeneron Pharmaceuticals, Inc; Sanofi; Teva Pharmaceutical Industries, Ltd. We are grateful tor Antonella Zambon fo statistical suggestions and support.

Declaration of interest

The authors report no conflicts of interest relevant to the manuscript. The authors alone are responsible for the content and writing of the paper.