TABLE 1.
Patient Demographic and Clinical Characteristics During Year 1 (2012)
| Characteristic | Persistent Asthma n = 63,597 | Severe Asthma n = 1,762 | P Valuea |
|---|---|---|---|
| Age in years, mean [SD] | 46.5 [19.0] | 50.8 [16.6] | < 0.001 |
| Age, n (%) | |||
| 12-17 | 7,207 (11.3) | 86 (4.9) | < 0.001 |
| 18-64 | 45,044 (70.8) | 1,320 (74.9) | < 0.001 |
| ≥ 65 | 11,346 (17.8) | 356 (20.2) | 0.011 |
| Male gender, n (%) | 23,408 (36.8) | 604 (34.3) | 0.030 |
| Charlson comorbidity score, mean [SD] | 1.31 [0.85] | 1.47 [1.04] | < 0.001 |
| Charlson comorbidity score, n (%) | |||
| 0 | 65 (0.1) | 0 | |
| 1-2 | 56,838 (89.4) | 1,487 (84.4) | < 0.001 |
| 3-4 | 5,660 (8.9) | 230 (13.1) | < 0.001 |
| ≥ 5 | 1,034 (1.6) | 45 (2.6) | 0.003 |
| Severe asthma exacerbation, n (%)b | |||
| 0 | 33,889 (53.3) | 0c | < 0.001 |
| 1 | 20,656 (32.5) | 0c | < 0.001 |
| 2 | 5,574 (8.8) | 1,013 (57.5) | < 0.001 |
| ≥ 3 | 3,478 (5.5) | 749 (42.5) | < 0.001 |
| U.S. Census region, n (%) | |||
| Northeast | 8,949 (14.1) | 248 (14.1) | 0.498 |
| South | 25,898 (40.7) | 702 (39.8) | < 0.001 |
| Midwest | 18,559 (29.2) | 548 (31.1) | < 0.001 |
| West | 10,184 (16.0) | 264 (15.0) | 0.024 |
| Other | 7 (0.01) | 0 | 0.891 |
| Health insurance plan type, n (%) | |||
| Commercial | 52,090 (81.9) | 1,363 (77.4) | < 0.001 |
| Medicare Advantage | 11,057 (18.1) | 399 (22.6) | < 0.001 |
a T-test for continuous variables and chi-square test for categorical variables.
b Asthma exacerbation defined as any asthma-related hospitalization, asthma-related ER visit, or asthma-related physician/outpatient visit coupled with OCS claim within 7 days.
c Inclusion in the severe asthma cohort required at least 2 asthma exacerbations in year 1.
ER = emergency room; OCS = oral corticosteroid; SD = standard deviation.