CHA2DS2-VASc score as a predictor of cardiovascular and all-cause mortality in a prospective cohort of hemodialysis patients of predominantly African ancestry: The PROHEMO

Abstract

Background: Patients with chronic kidney disease undergoing maintenance hemodialysis (MHD) have an increased mortality. The CHA2DS2-VASc score, initially used for stroke prediction in atrial fibrillation, is relevant for various cardiovascular conditions. This study evaluates its effectiveness in predicting cardiovascular and all-cause mortality in MHD patients.

Methods: Data are from the "Prospective Study of the Prognosis of Patients on Chronic Hemodialysis" (PROHEMO) in Salvador, Brazil. Patients were divided by CHA2DS2-VASc scores: ≤2 and >2. Cox regression estimated hazard ratios (HR) for death, both unadjusted and adjusted for confounders. We assessed the distribution of each score variable and its association with mortality. A modified CHA2DS2-VASc score was created due to the low percentage of patients over 75 (1.3%) and normotensive (4.6%).

Results: A total of 237 patients (mean age 51.6 years; 57.0% male) were included in the study. There were 55 deaths, 21 from cardiovascular causes. For patients with a CHA2DS2-VASc score >2, the unadjusted hazard of all-cause mortality was doubled (HR = 2.05; 95% CI: 1.20, 3.49) compared to those with a score ≤2, and the risk for cardiovascular deaths was more than threefold (HR = 3.53; 95% CI: 1.46, 8.54). These ratios remained consistent after adjusting for covariates. In the most comprehensive Cox model, the HR for all-cause mortality was 2.43 (95% CI: 1.38, 4.23) and for cardiovascular mortality was 3.52 (95% CI: 1.40, 8.84), similar to results from the modified CHA2DS2-VASc score.

Conclusions: The results support the CHA2DS2-VASc score as a practical tool for identifying MHD patients at higher risk of mortality, especially from cardiovascular causes.