Table 4.
Characteristics of patients classified with the exacerbation-risk score
| Exacerbation-risk score | P-value* | ||||
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | ||
| (N = 72) | (N = 19) | (N = 6) | (N = 7) | ||
| Patients with exacerbation of asthma, n (%) | 1 (1.4) | 2 (10.5) | 2 (33.3) | 6 (85.7) | < 0.001 |
| Age, mean (SD) | 54.1 ± 14.6 | 56.1 ± 17.3 | 47.2 ± 20.0 | 59.7 ± 18.4 | 0.321 |
| Sex, M: F, n (%) | 24 (33.8): 48 (66.7) | 13 (68.4): 6 (31.6) | 2 (33.3): 4 (66.7) | 3 (42.9): 4 (57.1) | 0.050 |
| BMI, median (IQR) | 22.9 (20.6–27.4) | 23.1 (21.5–26.7) | 23.1 (19.6–28.6) | 27.9 (21.8–30.1) | 0.538 |
| Smoking, n (%) | |||||
| Current smoker | 8 (11.1) | 1 (5.3) | 0 (0) | 1 (28.6) | 0.527 |
| Ex-smoker | 19 (26.4) | 6 (31.6) | 4 (66.7) | 2 (14.3) | |
| Never-smoker | 45 (62.5) | 12 (63.2) | 2 (33.3) | 4 (57.1) | |
| Asthma control, n (%) | |||||
| Well controlled | 20 (27.8) | 7 (36.8) | 3 (50.0) | 0 (0) | < 0.001 |
| Partially controlled | 42 (58.3) | 9 (47.4) | 1 (16.7) | 1 (14.3) | |
| Uncontrolled | 10 (13.9) | 3 (15.8) | 2 (33.3) | 6 (85.7) | |
| Treatment step, n (%) | |||||
| 1 | 4 (5.5) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0.005 |
| 2 | 11 (15.3) | 1 (5.3) | 1 (16.7) | 1 (14.2) | |
| 3 | 16 (22.2) | 4 (21.0) | 0 (0.0) | 0 (0.0) | |
| 4 | 39 (54.2) | 12 (63.2) | 2 (33.3) | 3 (42.9) | |
| 5 | 2 (2.8) | 2 (10.5) | 3 (50.0) | 3 (42.9) | |
| sST2 (ng/ml), median (IQR) | 11.0 (8.8–13.0) | 21.1 (18.8–28.4) | 11.8 (11.4–14.3) | 26.4 (20.8–34.0) | < 0.001 |
| WBC (/μL), median (IQR) | 6200 (5225–6800) | 5900 (4700–7200) | 10,250 (9000–12,350) | 10,500 (9700–12,100) | < 0.001 |
| Neutrophil (/μL), median (IQR) | 3496 (2786–4268) | 3553 (2248–4650) | 6333 (6117–10,381) | 8159 (7497–9196) | < 0.001 |
| Eosinophil (/μL), median (IQR) | 199 (133–335) | 201 (45–307) | 229 (75–677) | 87 (32–303) | 0.273 |
| Eosinophil (%), median (IQR) | 3.7 (2.1–6.2) | 3.4 (0.9–4.9) | 2.4 (0.6–7.4) | 1.0 (0.3–2.5) † | 0.045 |
| CRP (mg/dl), median (IQR) | 0.1 (0–0.2) | 0.0 (0–0.) | 0.1 (0–0.4) | 0.1 (0.1–0.5) | 0.195 |
| IgE (IU/ml), median (IQR) | 201 (45–684) | 236 (104–330) | 60 (8–843) | 73 (3–2656) | 0.432 |
| IL-8 (pg/ml), median (IQR) | 13.0 (10.5–15.8) | 21.9 (9.7–31.0) † | 11.7 (7.9–19.8) | 16.0 (11.0–25.2) | 0.063 |
| IL-6 (pg/ml), median (IQR) | 1.0 (0.5–1.8) | 0.9 (0.5–1.9) | 2.5 (1.2–8.0) | 1.8 (0.3–3.7) | 0.143 |
| Serum H2O2 (U. CARR), median (IQR) | 345 (315–401) | 322 (294–356) | 341 (304–390) | 383 (336–390) | 0.182 |
| FeNO (ppm), median (IQR) | 23.5 (16.0–38.3) | 24.0 (15.0–63.0) | 19.0 (13.3–49.8) | 16.0 (11.0–121.0) | 0.892 |
| EBC H2O2 (U. CARR) a | 0.4 (0.0–1.0) | 0.5 (0.2–1.1) | 0.4 (0.0–0.6) | 0.6 (0.3–0.7) | 0.751 |
| VC (L), median (IQR) | 2.9 (2.5–3.8) | 3.7 (2.6–4.4) | 3.7 (3.3–3.8) | 2.3 (2.0–2.9) † | 0.079 |
| %VC (%), mean (SD) | 106.7 (45.6) | 107.9 (19.5) | 114.0 (13.0) | 87.3 (14.2) ‡ | 0.014 |
| FVC (L), median (IQR) | 2.9 (2.4–3.7) | 3.7 (2.5–4.4) | 3.6 (3.2–3.8) | 2.2 (1.8–2.9) † | 0.087 |
| %FVC (%), mean (SD) | 98.6 (14.6) | 97.1 (15.4) | 107.1 (15.4) | 79.4 (12.1) ‡ | 0.009 |
| FEV1 (L), median (IQR) | 2.3 (1.8–2.7) | 2.5 (1.4–3.1) | 2.8 (2.0–3.0) | 1.6 (1.3–1.9) | 0.142 |
| %FEV1 (%), mean (SD) | 90.1 (17.8) | 86.5 (23.5) | 97.7 (24.3) | 71.1 (22.3) ‡ | 0.063 |
| FEV1/FVC (%), median (IQR) | 76.0 (69.2–81.0) | 70.3 (67.6–79.8) | 79.4 (66.0–82.0) | 73.6 (64.0–83.6) | 0.550 |
*P-values for parametric, non-parametric, and categorical data were calculated using a one-way ANOVA test, Kruskal-Wallis test, and Chi-square test, respectively
†P < 0.05 vs. a score of 0, calculated using the Steel test
‡P < 0.05 vs. a score of 0, calculated using the Dunnett test
*†‡ Bold letters, P < 0.05
aA total of 81 patients (scores of 0, 1, 2, and 3: N = 56, 17, 4, and 4, respectively) were evaluated
BMI body mass index, WBC white blood cells, FeNO fractional exhaled nitric oxide, EBC exhaled breath condensate, SD standard deviation, IQR interquartile range