Table 1. Characteristics of the studied cohorts.
| UKBiobank | GoSHARE (a) | GoSHARE (b) | BREATHE | Tayside RCT | PAGES | GALA II | SAGE | |
|---|---|---|---|---|---|---|---|---|
| N asthmatics | 72,754 | 10,218 | 546 | 62 | 361 | 3,343 | 977 | |
| N montelukast users | 1,561 | 953 | 88 | 210 | 62 | 163 | 486 | 71 |
| Asthma onset | Late | Late | Early | Early | Early | Early | Early | Early |
| Ethnicity | Europeans | Europeans | Europeans | Europeans | Europeans | Europeans | Hispanics/Latinos | African Americans |
| % male (n) | 33.5 | 44 | 21 | 61 | 63 | 60 | 57 | 45 |
| Mean age (SD) years | 43 (12) | 40 (16) | 9 (5) | 10 (4) | 11 (3) | 10 (3) | 11.9 (3.0) | 12.2 (3.1) |
| Study type | Cross-sectional study with Longitudinal prescription data | Longitudinal | Longitudinal | Cross-sectional | Cross-sectional | Cross-sectional | Cross-sectional | Cross-sectional |
| Exacerbation in 6–12 month | OCS, hospitalization, ER2 | OCS, hospitalization, ER2 | OCS, hospitalization, ER2 | OCS, hospitalization, school absence1 | OCS, hospitalization, school absence1 | OCS, hospitalization, school absence1 | OCS, hospitalization, ER2 | OCS, hospitalization, ER2 |
| Exacerbation (%) | 12.6 | 13 | 12 | 22 | 19 | 67 | 72 | 73 |
| Exacerbation 12 months before first montelukast prescription (%) | 29 | 19 | 21 | - | - | - | - | - |
| rs2660845 G variant frequency | 0.27 | 0.27 | 0.27 | 0.27 | 0.28 | 0.26 | 0.46 | 0.32 |
1Exacerbation within 6 months
2Exacerbation within 12 months. OCS: Oral Corticosteroids, ER: Emergency Room visit. Asthma onset is defined as early.