Table 1.
Characteristics of the Study Population by pre-ICU health categoriesa
| Characteristics | All (N=47,427) | Robust (N=8,901) | Cancer (N=13,571) | Chronic Organ Failure (N=32,287) | Frailty (N=16,147) |
|---|---|---|---|---|---|
| Male, n (%) | 22,734 (47.9) | 3,950 (44.4) | 7,866 (58.0) | 15,982 (49.5) | 6,883 (42.6) |
| Age, mean (yrs) ± SD | 77.5 ± 7.2 | 76.4 ± 7.2 | 77.6 ± 6.9 | 77.6 ± 7.10 | 79.4 ± 7.3 |
| Race/Ethnicity, n (%) | |||||
| White, non-Hispanic | 41,311 (87.1) | 7,702 (86.5) | 12,215 (90.0) | 28,186 (87.3) | 13,676 (84.7) |
| Black, non-Hispanic | 4,126 (8.7) | 822 (9.2) | 947 (7.0) | 2,740 (8.5) | 1,763 (10.9) |
| Other | 1,990 (4.2) | 377 (4.2) | 405 (3.0) | 1,361 (4.2) | 708 (4.4) |
| Hospitalized in year prior, n (%) | 17,780 (37.5) | 632 (7.1) | 5,865 (43.2) | 15,406 (47.9) | 10,148 (62.9) |
| SNF in year prior, n (%) | 5,016 (10.6) | n/a | 1,459 (10.7) | 4,436 (13.7) | 5,016 (31.1) |
| ICU length of stay, median days (IQR) | 3 (1–5) | 2 (1–5) | 3 (1–5) | 3 (1–6) | 3 (1–6) |
| Hospital length of stay, median days (IQR) | 6 (3–11) | 5 (3–9) | 7 (4–12) | 6 (3–11) | 7 (4–12) |
| Surgical patients, n (%)b | 21,746 (45.9) | 4,568 (51.3) | 6,846 (50.5) | 14,121 (43.7) | 5,898 (36.5) |
| Clinical Diagnoses during Index Hospitalization, n (%) | |||||
| Pneumonia | 2,479 (5.2) | 242 (2.7) | 678 (5.0) | 2,044 (6.3) | 1,098 (6.8) |
| Infection | 15,956 (33.6) | 2,364 (26.6) | 4,549 (33.5) | 11,404 (35.3) | 7234 (44.8) |
| Acute Renal Failure | 5,990 (12.6) | 84.1 (9.5) | 1,732 (12.8) | 4,404 (13.6) | 2,585 (16.0) |
| Severe Sepsisc | 7,579 (16.0) | 978 (11.0) | 2,199 (16.2) | 5,670 (17.6) | 3,604 (22.3) |
| Mechanical Ventilation | 5,151 (10.9) | 808 (9.1) | 1,505 (11.1) | 3,729 (11.6) | 2,085 (12.9) |
| Discharge Destination, n (%) | |||||
| Died in hospital | 5,991 (12.6) | 867 (9.7) | 1,843 (13.6) | 4,322 (13.4) | 2,786 (17.3) |
| Home with self care | 18,315 (38.6) | 4,177 (46.9) | 5,186 (38.2) | 11,950 (37.0) | 3,715 (23.0) |
| Home with health services | 6,407 (13.5) | 1,137 (12.8) | 2,041 (15.0) | 4,444 (13.8) | 1,921 (11.9) |
| Skilled Care Facility/Rehab | 13,058 (27.5) | 2,007 (22.6) | 3,490 (25.7) | 9,127 (28.3) | 6,430 (39.8) |
| Otherd | 9,647 (20.3) | 1,580 (17.8) | 2,853(21.0) | 6,766 (21.0) | 4,081(25.3) |
Notes
Abbreviations: ICU – Intensive Care Unit; SD – Standard Deviation; IQR – interquartile range; SNF – Skilled Nursing Facility; NA – not applicable
Elderly Medicare recipients are grouped based on pre-ICU Medicare claims in the year prior to the index hospitalization during which they received intensive care; patients could be classified into more than one category, thus the groups together add to more than the total cohort.
Diagnosis-related groups were used to classify the index hospitalization as primarily medical or surgical
Severe Sepsis included those patients with infection and acute organ dysfunction (see text for details)
Includes those who left against medical advice or were discharged to other inpatient facility, federal health care facility, hospice or psychiatric hospital