Number and percentage of individuals by drug use type and regularity of use within cases and controls
| Regular use of | Cases, n=3319 n (% within row) | Controls, n=43 023 n (% within row) | ||||
|---|---|---|---|---|---|---|
| Regular exposure* | Irregular exposure | No exposure† | Regular exposure* | Irregular exposure | No exposure† | |
| ICS+LABA‡ | 180 (5.4) | 585 (17.6) | 2554 (77.0) | 1903 (4.4) | 5088 (11.8) | 36 032 (83.8) |
| Separate inhalers | 43 (1.3) | 403 (12.1) | 2873 (86.6) | 436 (1.0) | 1877 (4.4) | 40 710 (94.6) |
| Single inhaler | 133 (4.0) | 403 (12.1) | 2783 (83.9) | 1416 (3.3) | 3320 (7.7) | 38 287 (89.0) |
| Budesonide+formoterol | 123 (3.7) | 68 (2.0) | 3128 (94.2) | 1152 (2.7) | 618 (1.4) | 41 253 (95.9) |
| Fluticasone+salmeterol | 84 (2.5) | 290 (8.7) | 2945 (88.7) | 892 (2.1) | 2294 (5.3) | 39 837 (92.6) |
| ICS alone | 354 (10.7) | 1483 (44.7) | 1482 (44.7) | 5259 (12.2) | 16 676 (38.8) | 21 088 (49.0) |
| LABA alone | 33 (1.0) | 77 (2.3) | 3209 (96.7) | 202 (0.5) | 680 (1.6) | 42 141 (97.9) |
*Regular exposure was defined as having a record of at least one dispensation of the corresponding medication in each of the four-month periods in the 12 months before the index date.
†No exposure to ICS+LABA means the individual was not exposed to ICS nor to LABA in the 12 months prior to the index date. No exposure to ICS alone means the individual did not dispense ICS (either monotherapy or in a combined inhaler with LABA). Similarly, No exposure to LABA alone means the individual did not dispense LABA (either monotherapy or in a combined inhaler with ICS).
‡Number of regular ICS+LABA users is more than the sum of regular single-inhaler and regular double inhaler users because some individuals switched from single-inhaler to double-inhaler ICS+LABA, or vice versa, thus satisfying the criteria for regular ICS+LABA use but not the criteria for combination or separate inhaler use . The same reason causes the sum of irregular users of budesonide+formoterol and fluticasone+salmeterol to be more than the number of irregular users of single- inhaler ICS+LABA.
ICS, inhaled corticosteroids; LABA, long-acting β-agonists.