Table 2.
Demographic, Comorbidity and Drug Exposure Variables for Asthma Cases and Matched Controls : Pharmetrics Claims Data 1997–2009
| Variable | Cases | Controls | ||
|---|---|---|---|---|
| N = 28,892 | N = 86,676 | |||
| Demographic variables | ||||
| Age (Mean, SD) | ||||
| Age at index date (years) | 42.77 | 15.1 | 42.77 | 15.1 |
| Gender (n,%) | ||||
| male | 10878 | 37.7% | 32634 | 37.7% |
| Region (n,%) | ||||
| East | 6717 | 23.3% | 20151 | 23.3% |
| West | 4125 | 14.3% | 12375 | 14.3% |
| Mid West | 11207 | 38.8% | 33621 | 38.8% |
| South | 6843 | 23.7% | 20529 | 23.7% |
| Health system variables (n,%) | ||||
| Medicaid | 927 | 3.2% | 1598 | 1.8% |
| Commercial HMO | 7791 | 27.0% | 24280 | 28.0% |
| Medicare | 942 | 3.3% | 2402 | 2.8% |
| non-HMO commercial and unknown type | 19232 | 66.6% | 58396 | 67.4% |
| Pre-index exposure to drugs that increase the risk of asthma (n,%) | ||||
| Antibiotic exposure - 30 days | 4327 | 15.0% | 6091 | 7.0% |
| Antibiotic exposure - 365 days | 14325 | 49.6% | 32227 | 37.2% |
| NSAID exposure - 30 days | 942 | 3.3% | 1920 | 2.2% |
| NSAID exposure - 365 days | 5094 | 17.6% | 12004 | 13.9% |
| Beta blocker exposure - 30 days | 1432 | 5.0% | 3992 | 4.6% |
| Beta blocker exposure - 365 days | 1906 | 6.6% | 5256 | 6.1% |
| Use of unmixed-opioids – 365 days | 565 | 1.9% | 1247 | 1.4% |
| Comorbidity variables in the 365 days pre-index (n,%) | ||||
| Eczema | 1640 | 5.7% | 3614 | 4.2% |
| Respiratory tract infection | 10424 | 36.1% | 14712 | 17.0% |
| Rhinitis | 5307 | 18.4% | 5091 | 5.9% |
| COPD | 1546 | 5.4% | 1042 | 1.2% |
| GERD | 1674 | 5.8% | 3151 | 3.6% |
| Cancer | 2003 | 6.9% | 5557 | 6.4% |
COPD : Chronic obstructive pulmonary disease ; GERD: Gastro-esophageal reflux disease; NSAID: Non-steroidal anti-inflammatory drugs.
p-values for all variables < 0.05