Abstract: 【Abstract】Objective To investigate the prevalence and the influencing factors involved in vascular calcification (VC) in maintenance hemodialysis (MHD) patients. Method A total of 154 patients treated with MHD at the Department of Blood Purification, the First Affiliated Hospital of Xi'an Jiaotong University were enrolled in this study. Demographics data at baseline were collected. Malnutrition-inflammation complex syndrome (MICS) was evaluated using the nutrition inflammatory score (MIS). Laboratory examinations including hypersensitive C-reactive protein (hs-CRP), calcium (Ca²⁺), phosphorus (P), albumin (ALB), parathyroid hormone (PTH) and serum vitamin K2 were conducted. Patients were divided into two groups based on the presence or absence of abdominal aortic calcification assessed by lateral lumbar radiography. Results ①The rate of VC was 48.7%. All of the patients with VC had different degrees of MICS; MIS score was significantly higher in VC group than in non-VC group (8.27±3.52 vs. 5.56±3.07, t=-5.095, P＜0.001), and MIS score increased along with the increase of VC rate (χ²=21.673, P＜0.001). ②The mean value of serum vitamin K2 in this cohort of MHD patients was 1.88±0.38nmol/L, and the level was significantly lower in VC group than in non-VC group (1.77±0.39 vs. 1.97±0.35nmol/L, t=2.473, P=0.016). ③Multivariate regression analysis indicated
that age (OR=1.165, 95% CI 1.055～1.286, P＜0.001) and MICS (OR=1.440, 95% CI 1.009～1.910, P=0.045) were the risk factors for VC, and serum vitamin K2 was the protective factor for VC (OR=0.062, 95% CI 0.007～0.559, P=0.013) after corrections of dialysis age, Ca2 +xP product, 25-(OH) D₃ and the history of coronary arteriosclerosis heart disease. Conclusion The incidence of VC in MHD patients is higher than that in the general population. Older age and malnutrition-microinflammatory state are the independent risk factors for VC in MHD patients, and increase of serum vitamin K2 is a favorable factor for the prevention of VC.

Key words: Hemodialysis, Vascular calcification, Malnutrition inflammation complex syndrome, Vitamin K₂