Table 1 Characteristics of patients who underwent coronary artery bypass graft surgery

Patient characteristics

n = 20,789

n = 4,000

n = 24,789

P value

Age (years):

65 to 69

5,069 (77%)

1,487 (23%)

6,556 (100%)

70 to 74

5,488 (82%)

1,238 (18%)

6,726 (100%)

75 to 79

5,761 (87%)

876 (13%)

6,637 (100%)

80 to 84

3,513 (91%)

350 (9%)

3,863 (100%)

≥ 85

958 (95%)

49 (5%)

1,007 (100%)

< 0.001

Gender:

Men

12,522 (78%)

3,438 (22%)

15,960 (100%)

Women

8,267 (94%)

562 (6%)

8,829 (100%)

< 0.001

Race:

White

19,035 (83%)

3,804 (17%)

22,839 (100%)

Black

1,250 (90%)

133 (10%)

1,383 (100%)

Other

504 (89%)

63 (11%)

567 (100%)

< 0.001

Type of admission:

Elective

9,183 (80%)

2,289 (20%)

11,472 (100%)

Urgent

6,035 (85%)

1,083 (15%)

7,118 (100%)

Emergency

5,571 (90%)

628 (10%)

6,199 (100%)

< 0.001

Hospital CABG volume (annual mean):

< 240

10,988 (87%)

1,595 (13%)

12,583 (100%)

≥ 240

9,801 (80%)

2,405 (20%)

12,206 (100%)

< 0.001

Surgeon CABG volume (annual mean):

< 60

10,796 (87%)

1,605 (13%)

12,401 (100%)

≥ 60

9,993 (81%)

2,395 (19%)

12,388 (100%)

< 0.001

Coexisting conditions:

Diabetes mellitus

5,747 (82%)

1,227 (18%)

6,974 (100%)

< 0.001

Renal failure

2,006 (93%)

152 (7%)

2,158 (100%)

< 0.001

Myocardial infarction

7,207 (86%)

1,157 (14%)

8,364 (100%)

< 0.001

Congestive heart failure

6,593 (93%)

529 (7%)

7,122 (100%)

< 0.001

Hypertension

11,063 (80%)

2,851 (20%)

13,914 (100%)

< 0.001

Peripheral vascular disease

2,491 (84%)

474 (16%)

2,965 (100%)

0.813

Cerebrovascular disease

1,586 (86%)

265 (14%)

1,851 (100%)

0.027

Chronic pulmonary disease

5,014 (86%)

830 (14%)

5,844 (100%)

< 0.001

Malignancy

463 (84%)

85 (16%)

548 (100%)

0.687