Association of blood groups with prognosis in acute coronary syndrome

INTRODUCTION Multiple factors that affect the prognosis of acute coronary syndromes (ACS) have been identified. There are scarce data on the effect of the blood group on prognosis in this patient group.
OBJECTIVES We investigated the effect of ABO and Rh (D antigen) status on the prognosis of ACS.
PATIENTS AND METHODS A group of 418 consecutive hospitalized patients with ACS were analyzed. The follow‑up period was 2075 ±794 days. The primary endpoint was all‑cause mortality. A statistical analysis was performed for the following subgroups: ABO blood group, ABO blood group including Rhesus (Rh) factor (D antigen), Rh‑positive vs. Rh‑negative blood group, O blood group vs. non‑0 blood group, blood group with vs. without the B antigen, and blood group with vs. without the A antigen.
RESULTS A total of 348 patients (83.25%) were Rh-positive, while 70 (16.75%) were Rh‑negative. The Kaplan–Meier survival plots showed 7‑year mortality of 22.7% in patients with blood groups with Rh antigen and of 10% in patients without Rh antigen (P = 0.014). Other comparisons were not statistically significant. A multivariable Cox proportional hazards model identified blood group with D antigen as an independent predictor of mortality (hazard ratio, 7.758; 95% confidence interval, 1.748–34.417; P = 0.007).
CONCLUSIONS Of all blood groups, only the Rh‑positive blood group was an independent predictor of mortality in patients with ACS.