Exacerbations by patients with frequent and infrequent exacerbations in different periods of the study
| Number of exacerbations | Characteristics of reported exacerbations | ||||
|---|---|---|---|---|---|
| Not reported, n (%) | Reported, n (%) | Total | Treated with oral steroids, n (%) | Mean (SD) time between last exacerbation and evaluation (days) | |
| *Differences between frequent and infrequent exacerbators were tested using the χ2 or t test according to the nature of the variables. | |||||
| †Differences between the four periods were tested using the χ2 test. | |||||
| First period (1st to 2nd evaluation) | |||||
| Infrequent exacerbator | 15 (42.9%) | 20 (57.1%) | 35 | 5 (25%) | 51.6 (36.8) |
| Frequent exacerbator | 66 (39.8%) | 100 (60.2%) | 166 | 44 (44%) | 52.8 (40.2) |
| p value* | 0.734 | 0.115 | 0.901 | ||
| Second period (2nd to 3rd evaluation) | |||||
| Infrequent exacerbator | 44 (55%) | 36 (45%) | 80 | 12 (33.3%) | 52.1 (65.7) |
| Frequent exacerbator | 160 (56.7%) | 122 (43.3%) | 282 | 58 (47.5%) | 65.7 (59.0) |
| p value* | 0.782 | 0.132 | 0.281 | ||
| Third period (3rd to 4th evaluation) | |||||
| Infrequent exacerbator | 17 (54.8%) | 14 (45.2%) | 31 | 7 (50%) | 79.6 (55.6) |
| Frequent exacerbator | 95 (55.9%) | 75 (44.1%) | 170 | 27 (36%) | 53.9 (42.2) |
| p value* | 0.914 | 0.322 | 0.061 | ||
| Fourth period (4th to 5th evaluation) | |||||
| Infrequent exacerbator | 32 (65.3%) | 17 (34.7%) | 49 | 3 (17.6%) | 60.4 (40.3) |
| Frequent exacerbator | 129 (63.9%) | 73 (36.1%) | 202 | 33 (45.2%) | 74.7 (58.6) |
| p value* | 0.850 | 0.037 | 0.367 | ||
| Total | 558 | 457 | 1015 | 189 (41.4) | 60.6 (51.0) |
| p value† | <0.001 | 0.798 | 0.140 | ||