Byline: Xue-Ping. Chen, Qian-Qian. Wei, Ru-Wei. Ou, Yan-Bing. Hou, Ling-Yu. Zhang, Xiao-Qin. Yuan, Yun-Qian. Yao, De-Sheng. Jia, Qian. Zhang, Wei-Xue. Li, Hui-Fang. Shang
Creatine kinase is a muscle enzyme that has been reported at various levels in different studies involving patients with amyotrophic lateral sclerosis. In the present retrospective case-control study, we included 582 patients with amyotrophic lateral sclerosis and 582 age- and sex-matched healthy controls. All amyotrophic lateral sclerosis participants received treatment in the Department of Neurology, West China Hospital, China, between May 2008 and December 2018. Serum creatine kinase levels in patients with amyotrophic lateral sclerosis were significantly higher than those in healthy controls. Subgroup analysis revealed that serum creatine kinase levels in men were higher than those in women in both amyotrophic lateral sclerosis patients and healthy controls. Compared with patients with bulbar-onset amyotrophic lateral sclerosis, patients with limb-onset amyotrophic lateral sclerosis had higher creatine kinase levels. Spearman's correlation analysis revealed that serum creatine kinase levels were not correlated with body mass index, Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised score, or progression rate. After adjusting for prognostic covariates, higher log creatine kinase values were correlated with higher overall survival in the amyotrophic lateral sclerosis patients. We also investigated the longitudinal changes in serum creatine kinase levels in 81 amyotrophic lateral sclerosis patients; serum creatine kinase levels were decreased at the second blood test, which was sampled at least 6 months after the first blood test. Together, our results suggest that serum creatine kinase levels can be used as an independent factor for predicting the prognosis of amyotrophic lateral sclerosis patients. This study received ethical approval from the Ethics Committee of West China Hospital, China (approval No. 2015(236)) on December 23, 2015.
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that is characterized by the selective loss of motor neurons, resulting in muscle atrophy, weakness, and progressive paralysis (Sun et al., 2012; Turner et al., 2013). Differential diagnosis is important because other disorders can mimic ALS, but have different prognoses and treatments (Fogarty, 2019; Riancho et al., 2019). Creatine kinase (CK), a muscle enzyme, is used to differentiate between neurogenic and myopathic disorders. High serum CK levels are related to myopathic disorders, including polymyositis and muscular dystrophy (Munsat et al., 1973). Therefore, measuring serum CK levels during the diagnostic workup may be helpful for differentiating ALS from primary muscular disorders. However, previous investigations of serum CK levels have led to inconsistent results. Elevated serum CK has been reported in 23-100% of patients with ALS (Panitch and Franklin, 1972; Amrit and Anderson, 1974; Edmonds and Ziegler, 1975; Harrington et al., 1983; Sinaki and Mulder, 1986; Felice and North, 1998; Ilzecka and Stelmasiak, 2003; Lima et al., 2003; Sussmuth et al., 2003; Chahin and Sorenson, 2009). Additionally, some studies have reported significantly higher CK levels in men than in women (Amrit and Anderson, 1974; Felice and North, 1998), whereas another study found that the number of ALS patients with increased CK levels was not different between sexes (Lima...