We included 9375 stroke patients from the China National Stroke Registry III for analysis. Participants were divided into 4 groups according to albumin corrected-calcium quartiles. Composite end point comprised recurrent stroke, myocardial infarction, other ischemic vascular events, and all-cause mortality. Multivariable Cox or logistic regression was used to evaluate the independent association of albumin corrected-calcium with all-cause mortality, recurrent stroke, composite end point, and poor functional outcome (modified Rankin Scale score ≥3).
Compared with the lowest calcium quartile (<2.16 mmol/L), the adjusted hazard ratio (95% CI) of the top quartile (≥2.31 mmol/L) was 1.56 (1.11-2.18) for all-cause mortality, 1.06 (0.87-1.28) for recurrent stroke and 1.08 (0.90-1.01) for composite end point, and the adjusted odds ratio for poor functional outcome was 1.18 (0.96-1.44). The addition of serum calcium to conventional risk factors improved risk prediction of all-cause mortality, leading to a small but significant increase in C-statistics and reclassification with non-significant integrated discrimination improvement (C-statistics, p = 0.02; net reclassification index 11.8%, p = 0.038; integrated discrimination improvement 0.08%, p = 0.42).
High serum calcium levels at baseline were associated with all-cause mortality at 1-year after ischemic stroke, suggesting that serum calcium may be a potential prognostic biomarker and therapeutic target for ischemic stroke.
Copyright © 2021. Published by Elsevier B.V.