Table 1 Characteristics of the study population
|  | Derivation cohort N = 3572 | Historical validation cohort N = 1756 | Random sample combined cohort N = 396 |
|---|---|---|---|
Readmitted in 30Â days | 577 (16.2%) | 311 (17.7%) | 64 (16.2%) |
Demographics | Â | Â | Â |
Age, median (IQR) | 61 (51–72) | 62 (52–73) | 61 (52–71) |
Gender, Female (%) | 1541 (43.1%) | 759 (43.2%) | 162 (40.9%) |
Marital status, single* (%) | 2023 (56.6%) | 988 (56.3%) | 203 (51.3%) |
Race, Black†(%) | 1090 (30.5%) | 497 (28.3%) | 130 (32.8%) |
Distance from the zip code centroid to hospital, miles [median, (IQR)] | 9.6 (4.6–46.2) | 12 (4.6–53.6) | 9.4 (4.6–46.2) |
Comorbidities | Â | Â | Â |
Charlson Score‡, median (IQR) | 3 (1–4) | 3 (2–5) | 3 (2–4) |
Solid tumor | 192 (5.4%) | 104 (5.9%) | 27 (6.8%) |
Other neurologic disease | 185 (5.2%) | 95 (5.4%) | 18 (4.6%) |
Hypertension | 2,533 (70.9%) | 1,239 (70.6%) | 289 (73.0%) |
Lymphoma | 86 (2.4%) | 46 (2.6%) | 8 (2.0%) |
Abnormal weight loss | 231 (6.5%) | 94 (5.4%) | 34 (8.6%) |
Obesity | 550 (15.4%) | 258 (14.7%) | 67 (16.9%) |
Liver disease | 154 (4.3%) | 61 (3.5%) | 18 (4.6%) |
Peripheral vascular disease | 286 (8.0%) | 184 (10.5%) | 45 (11.4%) |
Arrhythmia | 1,149 (32.2%) | 722 (41.1%) | 145 (36.6%) |
Metastatic cancer | 106 (3.0%) | 74 (4.2%) | 15 (3.8%) |
Details of hospital visit | Â | Â | Â |
Length of stay, median (IQR) | 4 (2–7) | 4 (3–8) | 4 (2–7) |
Inpatient visit within the last 30Â days | 379 (10.6%) | 181 (10.3%) | 45 (11.4%) |
ED visit within the prior 30Â days | 167 (4.7%) | 94 (5.4%) | 18 (4.6%) |
Number of discharge medications | 12 (8–16) | 12 (8–16) | 12 (8–16) |
AMI | 1047 (29.3%) | 594 (33.8%) | 119 (30.1%) |
CHF | 1354 (37.9%) | 610 (34.7%) | 148 (37.4%) |
PNA | 1171 (32.8%) | 552 (31.4%) | 129 (32.6%) |