Impacts of Muscle Enzyme Levels on Progression and Survival in ALS Population: A Cohort Study and Meta‐Analysis

ABSTRACT Objective To explore the prognostic values of muscle enzymes in amyotrophic lateral sclerosis (ALS) and provide evidence for clinical applications of these blood parameters in evidence‐based medicine (EBM). Methods ALS patients were consecutively recruited and blood tests of muscle enzymes were recommended. Correlation analyses between muscle enzymes and clinical variables including progression rate were conducted. Multivariate survival analyses were conducted to explore impacts of parameters on ALS survival. PubMed, EMBASE, OVID, Web of Science, and Medline were searched to identify relevant studies, and meta‐analyses were conducted to explore the relationships between muscle enzymes and ALS progression rate and survival time. Results A total of 454 ALS patients in our cohort were included in analysis, around half of which reported abnormal creatine kinase (CK) levels. There were negative correlations between progression rate of ALS and levels of CK‐MB, aspartate aminotransferase (AST), lactate dehydrogenase (LDH) ( p < 0.05). Pooled analysis of two longitudinal studies indicated a weak correlation between serum levels of alanine aminotransferase (ALT) and survival time of ALS (HR 1.02, 95% CI 1.01, 1.02). Combined analysis indicated a significant relationship between serum levels of creatinine and ALS survival time (HR 0.93, 95% CI 0.92–0.95). Conclusions Abnormal CK levels were common in the ALS population, which were not significantly related to ALS progression rate or survival time. CK‐MB, AST, and LDH were potential indicators for ALS progression. ALT was weakly correlated to ALS survival time. Serum level of creatinine significantly declined in ALS patients, which was related to the longer survival time of ALS.