Association of Cardiac Valvular Calcifications and C-Reactive Protein With Cardiovascular Mortality in Incident Hemodialysis Patients: A Japanese Cohort Study

Abstract

Cardiac valve calcification is seen frequently in patients undergoing dialysis. Serum C-reactive protein (CRP) level also is reported to predict future cardiovascular events. We investigated the association among valve calcification, CRP level, and mortality in patients with end-stage renal disease who were just beginning hemodialysis (HD) therapy. Observational cohort. 1,290 consecutive patients who just started HD therapy were enrolled and were followed up to 10 years. Patients were divided into 3 groups according to number of calcified valves: those without valve calcification, those with calcification in a single (aortic or mitral) valve, and those with calcification in both valves. They also were divided into tertiles according to CRP level. Cardiovascular and all-cause mortality. Echocardiography and CRP measurement were performed within 1 month after beginning HD therapy. During follow-up (median, 51 months), 335 (25.9%) patients died, including 156 (12.1%) of cardiovascular disease. The adjusted HR for cardiovascular mortality was 2.80 (95% CI, 1.63-4.81) for 2 calcifications versus 0 (P < 0.001). Furthermore, the risk of cardiovascular mortality was 3.66-fold higher in patients with calcifications in both valves (highest tertile of CRP) compared with patients without valve calcification (lowest tertile of CRP; P < 0.001). Precise medical treatments or therapeutic interventions were not evaluated. Valve calcification and elevated CRP levels were not only related to additively increased risk of mortality, but also improved the prediction of mortality in patients with end-stage renal disease who had just begun HD therapy.