Table 1.
Characteristics of nonexacerbators and infrequent and frequent exacerbators
| Characteristics | Non exacerbators (n=58) | Infrequent exacerbators (n=12) | Frequent exacerbators (n=20) |
|---|---|---|---|
| Age, years | 66.2±6.5 | 69.6±4.6 | 68.0±6.4 |
| Male sex, n (%) | 53 (91.4) | 11 (91.7) | 14 (70.0)* |
| Body mass index, kg/m2 | 22.7±3.1 | 21.4±3.0 | 18.8±3.2***,# |
| Current smokers, n (%) | 26 (44.8) | 3 (25.0) | 3 (15.0)* |
| Smoking index, pack-years | 59.2±27.2 | 62.1±23.6 | 60.9±26.8 |
| Frequency of previous hospitalizations within the last | 0 | 1.67±0.39* (0–1) | 1.50±0.37* (0–1) |
| year, times/patient (range) | |||
| mMRC dyspnea scale, grades | 0.60±0.98 | 1.50±1.00* | 1.65±1.35** |
| Total CAT score, points | 8.29±6.12 | 15.8±5.61** | 21.2±10.8***,# |
| Spirometric stage I/II/III/IV, n (% of stage III and IV) | 18/26/12/2 (24.1) | 1/7/2/2 (33.3) | 0/11/4/5a (45.0) |
| Hypertension, n (%) | 19 (32.8) | 2 (16.7) | 6 (30.0) |
| Diabetes, n (%) | 23 (39.7) | 2 (16.7) | 6 (30.0) |
| Dyslipidemia, n (%) | 31 (53.5) | 6 (50.0) | 10 (50.0) |
| Gastroesophageal reflux disease, n (%) | 3 (5.2) | 3 (25.0) | 4 (20.0)a |
| Duration of COPD, years | 4.79±4.01 | 7.00±3.64 | 5.90±3.89 |
| Pneumococcal vaccination within 5 years, n (%) | 9 (15.5) | 1 (8.3) | 7 (35.0) |
| Required long-term oxygen therapy, n (%) | 2 (3.5) | 0 | 3 (15.0) |
| Required home ventilation support, n (%) | 1 (1.7) | 0 | 1 (5.0) |
| No respiratory medication, n (%) | 18 (31.0) | 2 (16.7) | 2 (10.0) |
| ICS–LABA–LAMA triple combo, n (%) | 7 (12.1) | 1 (8.3) | 4 (20.0) |
| ICS–LAMA or ICS–LABA double combo, n (%) | 1 (1.7) | 0 | 3 (15.0)a |
| LABA–LAMA double combo, n (%) | 4 (6.9) | 3 (8.3) | 1 (10.0) |
| LAMA or LABA alone, n (%) | 28 (48.3) | 8 (66.7) | 9 (45.0) |
| Regimen included ICS, n (%) | 8 (13.8) | 1 (8.33) | 7 (35.0) |
| Regimen included SRT, n (%) | 1 (1.7) | 1 (8.3) | 2 (10.0) |
| Regimen included mucolytic agents, n (%) | 0 | 1 (8.3)* | 0 |
| Prebronchodilator | |||
| FVC, L | 3.70±0.79 | 3.28±0.71 | 2.82±0.81** |
| FVC predicted, % | 105±18.0 | 93.4±15.6 | 88.6±18.2** |
| FEV1, L | 1.86±0.64 | 1.44±0.66 | 1.20±0.59** |
| FEV1 predicted, % | 65.4±21.9 | 50.8±19.9 | 47.5±21.4** |
| FEV1/FVC ratio, % | 50.0±13.5 | 42.6±13.1 | 42.0±14.5 |
| Postbronchodilator | |||
| FVC, L | 3.74±0.77 | 3.38±0.74 | 2.88±0.84** |
| FVC predicted, % | 106±18.0 | 95.4±15.6 | 88.6±18.2** |
| FEV1, L | 1.92±0.65 | 1.51±0.68 | 1.28±0.63** |
| FEV1 predicted, % | 67.3±21.8 | 53.5±20.2 | 50.4±22.6** |
| FEV1/FVC ratio, % | 51.2±13.9 | 43.9±13.7 | 43.3±14.2 |
| Reversibility of FEV1 postbronchodilation, % | 3.65±7.96 | 5.64±4.24 | 6.85±12.8 |
Notes:
a
P<0.05 vs nonexacerbators by χ2-test for trend.
*
P<0.05,
**
P<0.01, and
***
P<0.0001 vs nonexacerbators;
#
P<0.05 vs infrequent exacerbators. Data expressed as mean ± standard deviation and number (percentage) of patients.
Abbreviations: CAT, COPD Assessment Test; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; ICS, inhaled corticosteroids; LABA, long-acting β2-agonist; LAMA, long-acting muscarinic antagonist; mMRC, modified Medical Research Council; SRT, slow-release theophylline.