Table 1.
Baseline characteristics of the initiation and step-up populations
|
Initiation population (N = 56,347) |
Step-up population (N = 9169) |
|||||||
|---|---|---|---|---|---|---|---|---|
| pMDI (N = 39,746) | BAI (N = 9809) | DPI (N = 6792) | P-value | pMDI (N = 6245) | BAI (N = 1388) | DPI (N = 1536) | P-value | |
| Male sex | 17,294 (43.5) | 4062 (41.4) | 3013 (44.4) | <0.001 | 2735 (43.8) | 571 (41.1) | 735 (47.9) | 0.001 |
| Age at index date (y) | 28 (12–42) | 30 (13–45) | 22 (11–42) | <0.001 | 27 (10–45) | 21 (12–44) | 20 (11–42) | 0.150 |
| BMI [no. (%) with data] (kg/m2) | [n = 28,166 (70.9)] | [n = 7235 (73.8)] | [n = 4509 (66.4)] | <0.001 | [n = 4627 (74.1)] | [n = 1011 (72.8)] | [n = 1094 (71.2)] | 0.099 |
| 24.9 (21.3–29.3) | 25.0 (21.5–29.4) | 24.7 (20.9–29.0) | 24.9 (20.7–29.7) | 24.7 (20.4–29.4) | 24.1 (20.4–28.9) | |||
| Charlson comorbidity index | ||||||||
| 0 | 37,143 (93.5) | 9116 (92.9) | 6309 (92.9) | 0.162 | 5750 (92.1) | 1289 (92.9) | 1427 (92.9) | 0.873 |
| 1 | 1534 (3.9) | 397 (4.0) | 276 (4.1) | 116 (1.9) | 21 (1.5) | 24 (1.6) | ||
| ≥2 | 1069 (2.7) | 296 (3.0) | 207 (3.0) | 379 (6.1) | 78 (5.6) | 85 (5.5) | ||
| Socioeconomic status | 17.9 (9.9–31.4) | 17.4 (8.9–32.1) | 17.9 (8.6–35.3) | 0.218 | 19.8 (10.5–33.9) | 20.7 (10.2–32.7) | 20.1 (8.7–35.3) | 0.878 |
| Smoking status [no. (%) with data] | [n = 18,950 (47.7)] | [n = 4575 (46.6)] | [n = 2706 (39.8)] | 0.031 | [n = 3074 (49.2)] | [n = 679 (48.9)] | [n = 646 (42.1)] | 0.024 |
| Current smoker | 6917 (36.5) | 1668 (36.5) | 908 (33.6) | 985 (32.0) | 213 (31.4) | 244 (37.8) | ||
| Ex-smoker | 3452 (18.2) | 836 (18.3) | 491 (18.1) | 530 (17.2) | 103 (15.2) | 105 (16.3) | ||
| Non-smoker | 8581 (45.3) | 2071 (45.3) | 1307 (48.3) | 1559 (50.7) | 363 (53.5) | 297 (46.0) | ||
| Recorded comorbidity | ||||||||
| Rhinitis | 6254 (15.7) | 1765 (18.0) | 1191 (17.5) | <0.001 | 1344 (21.5) | 308 (22.2) | 357 (23.2) | 0.331 |
| GERD | 2545 (6.4) | 796 (8.1) | 474 (7.0) | <0.001 | 508 (8.1) | 125 (9.0) | 115 (7.5) | 0.323 |
| Cardiac disease | 1227 (3.1) | 302 (3.1) | 185 (2.7) | 0.266 | 216 (3.5) | 48 (3.5) | 56 (3.6) | 0.936 |
| 1+ prescriptions, prior 12 mo | ||||||||
| Beta blockers | 1121 (2.8) | 343 (3.5) | 184 (2.7) | 0.001 | 134 (2.1) | 24 (1.7) | 20 (1.3) | 0.082 |
| NSAIDs | 5974 (15.0) | 1576 (16.1) | 905 (13.3) | <0.001 | 1031 (16.5) | 223 (16.1) | 219 (14.3) | 0.099 |
| Acetaminophen | 6338 (15.9) | 1523 (15.5) | 1011 (14.9) | 0.069 | 1339 (21.4) | 257 (18.5) | 275 (17.9) | 0.001 |
Notes: Values shown are n (%) or median (interquartile range). P-values for comparison among the three cohorts calculated with χ2 test for categorical data, Kruskal–Wallis test for continuous data.
Abbreviations: BAI, breath-actuated inhaler; BMI, body mass index; DPI, dry powder inhaler; GERD, gastroesophageal reflux disease; pMDI, pressurized metered-dose inhaler; NSAIDs, nonsteroidal anti-inflammatory agents.