Table 1.
Demographic characteristics, comorbid diseases, and baseline asthma in each cluster
| Variables and characteristics, N = 190 | Cluster A (n = 80) | Cluster B (n = 76) | Cluster C (n = 34) | P‐value |
|---|---|---|---|---|
| Demographic characteristics | ||||
| Female, n (%) | 40 (50) | 45 (59) | 23 (68) | .190 |
| Age (y), mean ± SD | 51 ± 17 | 63 ± 18 | 59 ± 17 | <.001 |
| Up to 41 y | 23 (29) | 11 (14) | 5 (15) | <.001 |
| 41 y to <65 y | 38 (48) | 21 (28) | 15 (44) | |
| >65 y | 19 (24) | 44 (58) | 14 (41) | |
| BMI <18.5 kg/m2, n (%) | 20 (25) | 7 (9) | 3 (8) | .015 |
| BMI ≥30.0 kg/m2, n (%) | 8 (10) | 5 (7) | 5 (15) | .285 |
| Lifetime smoker, n (%) | 59 (74) | 42 (55) | 21 (62) | .052 |
| Current smoker, n (%) | 42 (53) | 18 (24) | 11 (32) | <.001 |
| Pack‐year, mean ± SD | 18 (19) | 15 (22) | 18 (25) | .145 |
| Pet ownership, n (%) | 29 (36) | 18 (24) | 11 (32) | .227 |
| Hypersensitivity symptoms to furred pets, n (%) | 26 (33) | 8 (11) | 7 (21) | .004 |
| Comorbid diseases, n (%) | ||||
| Allergic rhinitis | 41 (51) | 36 (47) | 15 (44) | .763 |
| Atopic eczema | 9 (11) | 9 (12) | 2 (6) | .618 |
| Chronic hyperplastic rhinosinusitis/nasal polyposis | 21 (26) | 22 (29) | 10 (29) | .910 |
| Diabetes | 8 (10) | 11 (15) | 4 (12) | .692 |
| Hyperlipidemia | 4 (5) | 19 (25) | 4 (12) | .002 |
| Hypertension | 18 (23) | 23 (30) | 6 (18) | .304 |
| Chronic obstructive pulmonary disease | 8 (10) | 11 (15) | 5 (15) | .648 |
| Inactive pulmonary tuberculosis | 3 (4) | 6 (8) | 2 (6) | .541 |
| Any psychological diseases | 7 (9) | 2 (3) | 0 (0) | .071 |
| Baseline asthma | ||||
| Asthma duration, mean ± SD | 17 ± 14 | 21 ± 20 | 18 ± 18 | .709 |
| Severity, n (%) | ||||
| Intermittent | 29 (36) | 25 (33) | 11 (32) | .803 |
| Mild persistent | 14 (18) | 17 (22) | 4 (12) | |
| Moderate persistent | 22 (28) | 18 (24) | 9 (26) | |
| Severe persistent | 15 (19) | 16 (21) | 10 (29) | |
| Aspirin‐intolerant asthma, n (%) | 3 (3.8) | 0 (0.0) | 2 (5.9) | .146 |
| Previous asthma exacerbation, n (%) | ||||
| Unscheduled visits in the past year (≥once) | 34 (43) | 31 (41) | 15 (44) | .944 |
| History of hospitalization for asthma | 40 (50) | 38 (50) | 17 (50) | 1.000 |
| Hospitalizations for asthma in the past year (≥once) | 16 (20) | 13 (17) | 5 (15) | .775 |
| History of NFA requiring mechanical ventilation | 6 (8) | 6 (8) | 2 (6) | .939 |
| Usual trigger of worsening of symptoms, n (%) | ||||
| Exposure to irritant | 37 (46) | 32 (42) | 21 (62) | .156 |
| Dampness/storm | 25 (31) | 20 (26) | 11 (32) | .733 |
| Alcohol/meal | 18 (23) | 18 (24) | 7 (21) | .937 |
| Cold air/climate change, | 59 (74) | 41 (54) | 25 (74) | .019 |
| Strain/stress | 50 (63) | 40 (53) | 23 (68) | .256 |
| Exposure to furred pets | 17 (21) | 6 (8) | 5 (15) | .063 |
| Exposure to house dust | 31 (39) | 21 (28) | 13 (38) | .295 |
BMI, body mass index; NFA, near‐fatal asthma.