Skip to main content

Table 1 The basic characteristics of the study patients

From: Factors associated with 30-day readmission of patients with heart failure from a Japanese administrative database

  Readmission No readmission P-value
Number of patients 4479 63778  
Age (years)    <0.0001
 Median 81 80  
 IQR 73–86 71–86  
 Category [n (%)]    
 <65 487 (10.9) 9898 (15.5)  
 65–74 802 (17.9) 11598 (18.2)  
 ≥75 3190 (71.2) 42282 (66.3)  
Male [n (%)] 2351 (52.5) 33981 (53.3) 0.305a
NYHA [n (%)]    <0.0001a
 I 254 (5.7) 5411 (8.5)  
 II 1235 (27.6) 19168 (30.1)  
 III 1652 (36.9) 22164 (34.8)  
 IV 1338 (29.9) 17035 (26.7)  
Charlson Comorbidity Index    <0.0001
 Median 2 2  
 IQR 1–3 1–3  
 Category [n (%)]    
 ≤1 1181 (26.4) 19906 (31.2)  
 2 1187 (26.5) 17992 (28.2)  
 3 1025 (22.9) 13543 (21.2)  
 ≥4 1086 (24.3) 12337 (19.3)  
LOS    0.571
 Median 19 19  
 IQR 12–29 12–29  
BMI    <0.0001
 Median 21.7 22.3  
 IQR 19.2–24.4 19.7–25.2  
Hospital volume    0.914
 Median 104 105  
 IQR 70–147 68–150  
 Category [n (%)]    
 ≤68 1079 (24.1) 16116 (25.3)  
 69–150 2356 (52.6) 31904 (50.0)  
 ≥151 1044 (23.3) 15758 (24.7)  
  1. IQR interquartile range; NYHA New York Heart Association functional class; LOS length of stay in hospital; BMI body mass index; Hospital volume number of cases hospitalized with heart failure
  2. aCalculated using the chi-square test; the remaining P-values were calculated with the Wilcoxon rank-sum test