Table 3.
Baseline comorbidity characteristics of the aggregated cohort, comparing readmitted to non-readmitted patients in index stays for the Charlson and Elixhauser Indices
| Overall (1,622,983) | Not Readmitted (1,375,099) | Readmitted (287,884) | P | |
|---|---|---|---|---|
| Charlson Index Composite | 2.16 ± 1.43 | 2.10 ± 1.39 | 2.41 ± 1.57 | <.001 |
| Charlson Index Grouping | ||||
| Index Score = 1 | 42.7% | 44.2% | 35.5% | <.001 |
| Index Score = 2 | 27.6% | 27.5% | 27.8% | |
| Index Score ≥ 3 | 29.7% | 28.3% | 36.8% | |
| Charlson Component Comorbidities | ||||
| Neurologic/Psychiatric | ||||
| Cerebrovascular disease | 3.1% | 3.0% | 3.5% | <.001 |
| Dementia | 1.8% | 1.8% | 1.9% | 0.041 |
| Hemiplegia/paraplegia | 0.3% | 0.3% | 0.3% | <.001 |
| Cardiovascular | ||||
| Congestive heart failure | 27.6% | 26.1% | 34.8% | <.001 |
| Peripheral vascular disease | 5.6% | 5.4% | 6.2% | <.001 |
| Myocardial infarction | 7.8% | 7.6% | 8.9% | <.001 |
| Respiratory | ||||
| Chronic pulmonary disease | 100.0% | 100.0% | 100.0% | – |
| Gastrointestinal | ||||
| Peptic ulcer disease | 0.8% | 0.8% | 0.9% | <.001 |
| Mild liver disease | 2.2% | 2.1% | 2.4% | <.001 |
| Moderate or severe liver disease | 0.2% | 0.1% | 0.2% | <.001 |
| Renal/Electrolyte Disorders | ||||
| Moderate or severe renal disease | 14.0% | 13.1% | 18.1% | <.001 |
| Infectious Disease | ||||
| HIV/AIDS | 0.2% | 0.2% | 0.3% | <.001 |
| Hematologic/Oncology | ||||
| Malignancy (any type) | 3.4% | 3.2% | 4.4% | <.001 |
| Metastatic solid tumor | 1.1% | 1.0% | 1.7% | <.001 |
| Rheumatologic and Musculoskeletal | ||||
| Connective tissue disease | 2.2% | 2.2% | 2.2% | 0.131 |
| Endocrine | ||||
| Diabetes mellitus | 16.5% | 16.4% | 17.0% | <.001 |
| Diabetes mellitus w/end-organ damage | 2.1% | 2.0% | 2.6% | <.001 |
| Elixhauser Index Composite | 17.0 ± 15.0 | 16.3 ± 14.7 | 20.5 ± 16.0 | <.001 |
| Elixhauser Comorbidity Domain Count | 3.99 ± 1.84 | 3.92 ± 1.81 | 4.37 ± 1.91 | <.001 |
| Elixhauser Component Comorbidities | ||||
| Neurologic/Psychiatric | ||||
| Paralysis | 1.3% | 1.2% | 1.5% | <.001 |
| Other neurologic disorders | 8.6% | 8.3% | 9.8% | <.001 |
| Alcohol abuse | 4.5% | 4.5% | 4.7% | <.001 |
| Drug abuse | 3.6% | 3.5% | 4.2% | <.001 |
| Psychoses | 6.3% | 6.1% | 7.6% | <.001 |
| Depression | 16.9% | 16.7% | 17.8% | <.001 |
| Cardiovascular | ||||
| Congestive heart failure | 26.9% | 25.4% | 34.0% | <.001 |
| Peripheral vascular disease | 7.9% | 7.7% | 9.2% | <.001 |
| Valvular Heart Disease | 6.5% | 6.2% | 7.5% | <.001 |
| Hypertension | 54.1% | 54.5% | 52.2% | <.001 |
| Respiratory | ||||
| Chronic pulmonary disease | 100.0% | 100.0% | 100.0% | – |
| Pulmonary circulation disorders | 7.9% | 7.6% | 9.8% | <.001 |
| Gastrointestinal | ||||
| Peptic ulcer disease | 0.1% | 0.1% | 0.2% | <.001 |
| Liver disease | 2.4% | 2.3% | 2.8% | <.001 |
| Renal/Electrolyte Disorders | ||||
| Renal Failure | 13.1% | 12.3% | 17.2% | <.001 |
| Fluid and electrolyte disorders | 28.0% | 27.4% | 30.9% | <.001 |
| Infectious Disease | ||||
| HIV/AIDS | 0.2% | 0.2% | 0.3% | <.001 |
| Hematologic/Oncology | ||||
| Solid tumor without metastasis | 3.4% | 3.1% | 4.6% | <.001 |
| Metastatic cancer | 1.1% | 1.0% | 1.7% | <.001 |
| Lymphoma | 0.5% | 0.5% | 0.6% | <.001 |
| Coagulopathy | 3.2% | 3.1% | 3.8% | <.001 |
| Blood loss anemia | 0.4% | 0.3% | 0.5% | <.001 |
| Deficiency anemia | 15.4% | 14.4% | 19.9% | <.001 |
| Rheumatologic and Musculoskeletal | ||||
| Rheumatoid arthritis and collagen vascular disorders | 3.3% | 3.3% | 3.5% | <.001 |
| Endocrine | ||||
| Diabetes mellitus (uncomplicated) | 26.3% | 25.8% | 28.4% | <.001 |
| Diabetes mellitus (complicated) | 6.0% | 5.7% | 7.3% | <.001 |
| Hypothyroidism | 13.7% | 13.6% | 14.0% | <.001 |
| Obesity | 19.1% | 19.0% | 19.6% | <.001 |
| Weight loss | 4.6% | 4.5% | 5.4% | <.001 |
Note: Unweighted N’s displayed. Frequencies derived using weighted analysis