Correlation between cystatin C and ALS: A cohort study and meta-analysis

Abstract

The study aimed to explore the prognostic role of cystatin C (Cys C) in amyotrophic lateral sclerosis (ALS). Patients with sporadic ALS were consecutively recruited and follow-up. Blood tests of Cys C were conducted at the first time of evaluation. Online database was systematically searched to identify studies on Cys C and ALS. Meta-analyses were conducted to provide evidence for clinical application of Cys C in ALS. A total of 143 ALS patients with available data of Cys C were included in our analysis. Correlation analyses revealed serum levels of Cys C were positively correlated with lower motor neuron (LMN) score (rho=0.180, p=0.032). Pooled results suggested that serum level of Cys C was significantly higher in ALS population than that in healthy controls (HCs) (MD 0.50, 95%CI 0.43- 0.57). In cerebrospinal fluid (CSF), the level of Cys C was predominantly higher in HCs than that in ALS (MD 0.32, 95%CI 0.12-0.53). There was a positive correlation between serum level of Cys C and progression rate in ALS (rho=0.18, 95%CI 0.10-0.25). Serum level of Cys C was a predictor of death or invasive respiratory support of ALS patients (HR 1.33. 95%CI 1.18-1.51). The level of Cys C was significantly elevated in serum and decreased in CSF among ALS population compared to HCs. Serum level of Cys C was significantly higher in patients with severe LMN involvement, and might act as a potential predictor of ALS progression and death.