Table 1.
Characteristics of Medicare AMI Admissions, 1995–1999
| Year | 1995 | 1996 | 1997 | 1998 | 1999 |
|---|---|---|---|---|---|
| Number of Cases | 305,468 | 308,997 | 306,224 | 304,882 | 306,175 |
| Female (%) | 48.1 | 48.4 | 48.4 | 49.1 | 49.6 |
| Race: (%) | |||||
| White | 90.3 | 89.9 | 89.5 | 89.4 | 88.9 |
| Black | 6.7 | 6.8 | 7.0 | 7.1 | 7.4 |
| Other | 3.0 | 3.3 | 3.4 | 3.5 | 3.6 |
| Mean age | 75.5 | 75.7 | 75.9 | 76.2 | 76.6 |
| Age group: (%) | |||||
| 18–64 | 6.8 | 7.0 | 7.2 | 7.3 | 7.4 |
| 65–74 | 38.9 | 37.6 | 36.1 | 34.5 | 32.6 |
| 75–84 | 38.5 | 38.8 | 39.2 | 39.3 | 39.6 |
| 85+ | 15.7 | 16.5 | 17.5 | 18.8 | 20.3 |
| Non-aged orig. entitlement (%) | 16.7 | 16.9 | 17.1 | 17.6 | 17.9 |
| Mean Charlson Index* | 3.20 | 3.26 | 3.29 | 3.41 | 3.49 |
| Mean DCG score* | 2.22 | 2.27 | 2.33 | 2.39 | 2.45 |
| Comorbidities (%) | |||||
| AMI code (past year) ** | 31.4 | 32.2 | 32.9 | 33.9 | 34.6 |
| Diabetes* | 38.0 | 39.3 | 40.8 | 42.8 | 44.7 |
| CHF* | 47.8 | 48.3 | 48.9 | 50.1 | 50.7 |
| One-year mortality (%) | 32.0 | 31.6 | 31.7 | 32.7 | 33.8 |
*
Comorbidity identification based on all diagnoses detected during inpatient or ambulatory care in the 365-day prehospitalization period plus those identified during the index admission.
**
Comorbidity identification based on the preperiod only. “AMI code” refers to either current (ICD-9-CM code of 410xx) or recent MI (412xx).