Association between vascular calcification assessed by simple radiography and non-fatal cardiovascular events in hemodialysis patients

Abstract

Background: Vascular calcification (VC) is one of the factors associated with cardiovascular mortality in hemodialysis (HD) patients. Recommendations concerning screening for VC differ. Possible ability to prevent and reversibility of VC are major subjects on debate whether screening for VC could improve outcomes of renal patients. The objective of the study was to evaluate the significance of simple vascular calcification score (SVCS) based on plane radiographic films and to test its association with non-fatal cardiovascular events in patients on chronic HD.

Methods: A study population consisted of 95 prevalent HD patients in the HD unit of Hospital of Lithuanian University of Health sciences Kaunas Clinics. Clinical data and laboratory tests information were collected from medical records. SVCS was evaluated as it is described by Adragao et al. After measurement of VC, HD patients were observed for novel non-fatal cardiovascular events.

Results: Patients were divided into two groups: SVCS≥3 (57 patients [60%]) and <3 (38 patients [40%]). The Kaplan-Meier survival curves show a significant difference in non-fatal cardiovascular events in the group with SVCS≥3 vs. <3 group (26.3% vs. 7.8%; log rank 5,49; P=0.018). Multivariate Cox regression analysis confirmed a negative impact of VC, hyperphosphatemia, and lower ejection fraction on cardiovascular events. No statistically significant differences were observed comparing parameters of Ca-P metabolism disorders between groups with different SVCS. On separate analysis, the presence of VC in hands was also associated with higher rate of novel cardiovascular events (score 0 goup-5 events [10.6%] vs. score≥1 group-13 events [27%], log rank P=0.035).

Conclusion: VC assessed by simple and inexpensive radiological method was an independent predictor of novel non-fatal cardiovascular events in HD patients.

Keywords: Ca-P metabolism disorders; Cardiovascular events; Vascular calcification.