Table 4.
Study cohort characteristics are stratified by COPD exacerbation status with a 2-year follow-up
| Characteristic | No Exacerbators (N = 53) | Mild Exacerbators (N = 15) | Moderate Exacerbators (N = 7) | Severe Exacerbators (N = 49) | P Value | ||||
|---|---|---|---|---|---|---|---|---|---|
| N | Value | N | Value | N | Value | N | Value | ||
| Ageb | 53 | 70(63,75) | 15 | 66(59,71) | 7 | 71(65,72) | 49 | 67(63,73) | 0.17 |
| Female genderc | 43 | 81.1% | 14 | 93.3% | 4 | 57.1% | 43 | 87.8% | 0.14 |
| BMIb | 53 | 21.2(18.4,22.6) | 15 | 21.5(19.1,23.7) | 7 | 18.6(17.9,24.2) | 49 | 20.8(17.7,22.8) | 0.62 |
| Smoking Index b | 53 | 800(25,1550) | 15 | 420(260,800) | 7 | 0(0,1600) | 49 | 600(375,950) | 0.38 |
| Duration of COPDb | 53 | 10(6,25) | 15 | 15(10,15) | 7 | 7(4,15) | 49 | 10(6,25) | 0.66 |
| Comorbiditiesc | 30 | 56.6% | 8 | 53.3% | 4 | 57.1% | 23 | 46.9% | 0.79 |
| Diabetes mellitusc | 9 | 17.0% | 1 | 6.7% | 0 | 0% | 4 | 8.2% | 0.33 |
| Coronary diseasec | 4 | 7.5% | 2 | 13.3% | 0 | 0% | 2 | 4.1% | 0.53 |
| Strokec | 1 | 1.9% | 0 | 0% | 1 | 14.3% | 1 | 2.0% | 0.20 |
| Hypertension c | 28 | 52.8% | 7 | 46.7% | 3 | 42.9% | 20 | 40.8% | 0.68 |
| Home oxygen therapyc | 14 | 26.4% | 6 | 40.0% | 1 | 14.3% | 25 | 51.0%b | 0.04 |
| Regular medicationc | 26 | 49.1% | 7 | 46.7% | 4 | 57.1% | 32 | 65.3% | 0.35 |
| Oral glucocorticoid therapyc | 3 | 5.7% | 1 | 6.7% | 0 | 0% | 1 | 2.0% | 0.70 |
| Theophylline therapyc | 0 | 0% | 0 | 0% | 0 | 0% | 2 | 4.1% | 0.38 |
| Expectorants therapyc | 13 | 24.5% | 6 | 40.0% | 1 | 14.3% | 14 | 28.6% | 0.56 |
| Inhaled COPD therapyc | - | - | - | - | - | - | - | 0.05 | |
| No inhaled treatmentc | 9 | 17.0% | 5 | 33.3% | 3 | 42.9% | 3 | 6.1% | |
| LAMAc | 3 | 5.7% | 2 | 13.3% | 0 | 0% | 4 | 8.2% | |
| ICS + LABAc | 12 | 22.6% | 1 | 6.7% | 2 | 28.6% | 5 | 10.2% | |
| LABA + LAMAc | 8 | 15.1% | 0 | 0% | 1 | 14.3% | 7 | 14.3% | |
| ICS + LABA + LAMAc | 21 | 39.6% | 7 | 46.7% | 1 | 14.3% | 30 | 61.2% | |
| SGRQ scoreb | 53 | 33.3(24.7,60.0) | 15 | 43.8(26.1,63.3) | 7 | 41.5(26.1,51.0) | 49 | 46.2(36.9,73.1)d | 0.04 |
| mMRC scoreb | 53 | 1(1,3) | 15 | 1(1,3) | 7 | 1(0,2) | 49 | 2(1,3)e | 0.04 |
| Exercise capacity scoreb | 53 | 1(1,2) | 15 | 1(1,2) | 7 | 1(1,2) | 49 | 2(1,2)e | 0.05 |
| CAT scorea | 53 | 21.0 ± 7.7 | 15 | 20.1 ± 8.6 | 7 | 18.1 ± 7.9 | 49 | 24.3 ± 7.4e | 0.049 |
| COPD-related exacerbation within the previous yearb | 53 | 0(0,1) | 15 | 0(0,1) | 7 | 0(0,2) | 49 | 1(0,2)d | 0.002 |
COPD chronic obstructive pulmonary disease, BMI body mass index, LAMA Long-acting muscarinic antagonists, LABA long-acting beta2-agonists, ICS inhaled corticosteroids, SGRQ St George's respiratory questionnaire, mMRC modified medical research council, CAT chronic obstructive pulmonary disease assessment test
Data are expressed as
amean ± SD
bmedian; 25–75th percentile
cdata are expressed as %. P values: One-way ANOVA was used to analyze the normally distributed continuous variables of within-group difference between the COPD exacerbation status. The Kruskal–Wallis test was used for the non-normally distributed variables. Chi-square (χ2) tests were used to analyze the categorical variables
dP < 0.001
eP < 0.05 for comparison with individuals with COPD but no exacerbation history