A multivariate Cox regression model was applied, including IAB severity, age, sex, PR interval, BMI, hypertension, diabetes mellitus, coronary artery disease, heart failure, chronic obstructive pulmonary disease, prior stroke/transient ischemic attack, chronic kidney disease stage, anemia, left atrial diameter, right atrial diameter, N-terminal pro b-type natriuretic peptide (NT-proBNP) levels, and clinical medications. The gene discussed is NPPB; the disease is anemia.