Table 1.

Descriptive Statistics of the Cohort

Characteristic	Number (%)
N	39,616
Age, mean (SD)	77.3 (7.5)
Race/ethnicity
Non-Hispanic whites	34,189 (86.3)
Non-Hispanic blacks	2,312 (5.8)
Hispanics	2,282 (5.8)
Others	833 (2.1)
Female	24,036 (60.7)
Surgery type
Coronary-artery bypass grafting	8,643 (21.8)
Lobectomy	1,164 (2.9)
Endovascular repair of abdominal aortic aneurysm	1,895 (4.8)
Open repair of abdominal aortic aneurysm	575 (1.5)
Colectomy	9,744 (24.6)
Hip replacement	17,595 (44.4)
Medicare and Medicaid dual eligible patients	10,944 (27.6)
Original reason for entitlement
Old age	34,812 (90.4)
Disability or end stage renal disease	3,804 (9.6)
Outcomes
30-day mortality	2,282 (5.8)
1-year mortality	6,991 (17.7)
30-day readmissions†	4,433 (14.1)
Complications	15,718 (39.7)
Failure to rescue‡	2,282 (14.5)

^†Denominator is 30,848. Patient died in the index hospitalization or admissions to non-prospective payment system hospital from both index and readmission were excluded (n=8,768).

^‡Denominator is 15,718.