Plasma VDBP, 25(OH)D, and GSH levels predict surgical outcome in patients with cervical spondylotic myelopathy

Abstract

This study intends to investigate the predictive values of plasma Vitamin D-binding protein (VDBP), 25-hydroxyvitamin D [25(OH)D], and glutathione (GSH) levels in the outcome of cervical spondylotic myelopathy (CSM) surgery. Surgery outcomes of 236 CSM patients were determined. Recovery rate was calculated according to Japanese Orthopaedic Association (JOA) scores during follow-up. CSM patients with a recovery rate >50% were assigned with good prognosis and the rest were with fair prognosis. Preoperative and postoperative neurologic function scores were compared among groups. Plasma VDBP and 25(OH)D levels, as well as GSH levels were measured by ELISA and glutathione reductase recycling assay, respectively. Pearson's correlation coefficient was performed to analyze the correlation among plasma VDBP, 25(OH)D, and GSH levels. Receiver operating characteristic (ROC) curve was applied to evaluate the predictive value of plasma VDBP, 25(OH)D, and GSH levels for surgical outcome. Logistic regression model was used to analyze risk factors for surgical outcome. Compared with those with fair prognosis, CSM patients with good prognosis group exhibited higher postoperative neurologic function scores, plasma VDBP, 25(OH)D, and GSH levels, and better improvements in spinal cord compression and motions of the cervical vertebra. Plasma VDBP, 25(OH)D, and GSH levels were favorable prognostic factors for CSM surgical outcome. The sensitivity and specificity of plasma VDBP, plasma 25(OH)D, and plasma GSH were 89.8% and 91.7%, 85.8% and 84.4%, and 79.5% and 91.7%, respectively. Our study provides evidence that higher plasma VDBP, 25(OH)D, and GSH levels may predict better surgical outcome in CSM patients.

Keywords: 25-hydroxyvitamin D; cervical spondylotic myelopathy; glutathione; surgical outcome; vitamin D-binding protein.