Table I.
Sample characteristics
| Characteristic | All, N = 2707 | Adalimumab, n = 1084 | Etanercept, n = 1025 | Infliximab, n = 318 | Ustekinumab, n = 280 |
|---|---|---|---|---|---|
| Age, mean (SD), y | 60.7 (14.5) | 59.4 (14.4) | 60.3 (14.9) | 65.5 (12.0) | 61.6 (15.1) |
| Age category, y | |||||
| <65 | 48.9% | 54.7% | 50.6% | 28.0% | 44.3% |
| 65–69 | 19.5% | 16.9% | 19.1% | 31.1% | 17.5% |
| 70–74 | 16.3% | 14.7% | 14.3% | 24.5% | 20.0% |
| 75–79 | 8.0% | 7.7% | 7.9% | 8.2% | 9.6% |
| ≥80 | 7.3% | 6.0% | 8.1% | 8.2% | 8.6% |
| Sex, male | 43.9% | 43.7% | 42.0% | 48.7% | 46.1% |
| Race | |||||
| White | 84.6% | 83.9% | 84.0% | 91.2% | 82.8% |
| Black | 6.5% | 7.2% | 6.7% | 3.5% | 6.1% |
| Hispanic | 3.5% | 2.6% | 4.1% | 3.1% | 5.0% |
| Other/unknown | 5.4% | 6.3% | 5.2% | 2.2% | 6.1% |
| Census region | |||||
| Northeast | 15.6% | 14.8% | 15.6% | 14.4% | 19.9% |
| Midwest | 22.4% | 22.5% | 23.8% | 23.3% | 16.1% |
| South | 43.2% | 43.0% | 41.3% | 48.1% | 45.4% |
| West | 18.8% | 19.7% | 19.3% | 14.2% | 18.6% |
| County-level characteristics | |||||
| Income, per capita, $10,000s, mean (SD) | 3.8 (1.1) | 3.8 (1.0) | 3.8 (1.0) | 3.8 (1.0) | 4.1 (1.4) |
| Dermatologists/10,000 residents, mean (SD) | 0.3 (0.3) | 0.3 (0.3) | 0.3 (0.3) | 0.3 (0.3) | 0.4 (0.4) |
| Part D low-income subsidy status | |||||
| Full | 60.6% | 69.5% | 62.5% | 27.8% | 55.7% |
| Partial | 1.6% | 1.4% | 2.0% | 0.9% | 1.8% |
| None | 36.6% | 28.2% | 33.9% | 70.4% | 41.1% |
| Mixed (switched status) | 1.2% | 0.9% | 1.6% | 0.9% | 1.4% |
| Drug benefit type | |||||
| Basic alternative | 30.5% | 25.3% | 32.7% | 40.3% | 31.8% |
| Defined standard benefit | 9.7% | 9.9% | 10.8% | 6.9% | 8.2% |
| Actuarially equivalent standard | 38.6% | 45.9% | 38.0% | 18.9% | 35.4% |
| Unknown | 3.8% | 3.8% | 3.7% | 3.8% | 3.9% |
| Comorbid conditions | |||||
| Rheumatologic disease | 1.8% | 1.6% | 1.5% | 4.1% | 1.4% |
| Congestive heart failure | 8.1% | 7.0% | 7.1% | 8.5% | 15.4% |
| Diabetes | 35.1% | 35.8% | 33.9% | 32.7% | 39.6% |
| Dyslipidemia | 53.1% | 51.3% | 52.4% | 60.4% | 54.6% |
| Hypertension | 61.4% | 59.8% | 60.0% | 67.0% | 66.1% |
| Obesity | 11.9% | 12.5% | 11.0% | 11.9% | 12.9% |
| Atherosclerotic conditions | 16.2% | 14.9% | 16.3% | 18.6% | 18.2% |
| Liver disease | 7.3% | 6.9% | 7.8% | 7.2% | 6.8% |
| Dementia | 1.0% | 0.6% | 1.3% | 1.9% | 1.1% |
| Depression | 19.8% | 21.6% | 19.6% | 16.7% | 17.5% |
| Psoriatic arthritis | 28.9% | 25.5% | 23.2% | 70.8% | 15.7% |
| Renal disease | 8.2% | 7.8% | 8.5% | 6.0% | 11.4% |
| Immunosuppressive conditions | 5.5% | 5.3% | 5.8% | 4.7% | 6.8% |
| No. of 30-d supply equivalent prescriptions for nonpsoriasis medications, mean (SD) | 4.89 (3.63) | 4.95 (3.78) | 4.79 (3.50) | 4.72 (3.36) | 5.21 (3.75) |
| RxHCC score, mean (SD) | 1.13 (0.65) | 1.15 (0.66) | 1.13 (0.67) | 1.09 (0.58) | 1.12 (0.59) |
| Index year | |||||
| 2010 | 46.4% | 47.6% | 51.3% | 42.1% | 46.4% |
| 2011 | 53.6% | 52.4% | 48.7% | 57.9% | 53.6% |
Rheumatologic disease category excludes rheumatoid arthritis. Atherosclerotic conditions category includes cerebrovascular disease, myocardial infarction, and peripheral vascular disease. Immunosuppressive conditions include HIV/AIDS, cancer, and metastatic solid tumor.
RxHCC, Prescription drug hierarchical condition category.