Table 1.
Demographic and clinical characteristics of the study population
| Variable | CAT score category
|
All (N=684) |
|||
|---|---|---|---|---|---|
| 0–10 (n=69) | 11–20 (n=228) | 21–30 (n=282) | 31–40 (n=105) | ||
| Age (years) | 65.8±10.5 | 68.7±9.4 | 69.5±9.1* | 68.8±8.9 | 68.7±9.3 |
| Sex (men) | 57 (82.6) | 197 (87.6) | 227 (81.4) | 89 (85.8) | 570 (84.1) |
| Active smoker | 16 (23.2) | 44 (19.5) | 60 (21.6) | 25 (24.3) | 145 (21.4) |
| COPD duration (years) | 7.6±6.2 | 10.1±7.6 | 12.1±6.6 | 15.8±9.4*** | 11.5±7.7 |
| FVC (mL) | 3,291±824 | 2,959±883 | 2,812±927 | 2,858±994*** | 2,917±922 |
| FVC (%) | 78.5±16.9 | 69.8±16.1 | 69.2±17.4 | 68.4±18.1*** | 70.2±17.2 |
| FEV1 (mL) | 1,876±616 | 1,725±739 | 1,630±719 | 1,619±759*** | 1,685±725 |
| FEV1 (%) | 58.0±15.3 | 53.5±15.8 | 51.4±16.6 | 48.6±17.5*** | 52.3±16.3 |
| FEV1/FVC | 56.5±11.8 | 55.8±11.2 | 53.5±12.3 | 53.0±13.8** | 5.5±12.2 |
| Cough (yes) | 34 (49.3) | 171 (76.7) | 255 (91.7) | 102 (97.1)*** | 562 (83.3) |
| Expectoration (yes) | 30 (43.5) | 137 (62.0) | 222 (89.4) | 93 (89.4)*** | 482 (72.3) |
| Dyspnea (yes) | 56 (81.2) | 220 (96.5) | 279 (99.6) | 105 (100)*** | 660 (96.8) |
| Exacerbations in the previous year (yes) | 47 (68.1) | 192 (84.2) | 268 (95.0) | 91 (86.7)*** | 598 (87.4) |
| Oxygen therapy at home (yes) | 3 (4.6) | 29 (13.4) | 87 (32.0) | 39 (40.2)*** | 158 (24.3) |
| BODEx | 1.4±1.4 | 2.2±1.5 | 3.4±1.8 | 4.2±1.6*** | 3.0±1.9 |
| MMSE | 28.8±1.8 | 27.0±3.5 | 25.7±4.0 | 23.9±5.7*** | 26.2±4.2 |
| BDI score | 3.5±3.3 | 6.0±3.9 | 10.8±5.5 | 14.4±7.4*** | 9.0±6.2 |
| Depression (yes) | 18 (26.1) | 142 (62.3) | 255 (90.4) | 101 (96.2)*** | 516 (75.4) |
| Severe depression (yes) | 1 (1.4) | 9 (3.9) | 54 (19.1) | 40 (38.1)*** | 104 (15.2) |
| Charlson index | 0.8±1.1 | 1.0±1.0 | 1.6±1.4 | 2.4±2.0*** | 1.4±1.4 |
| Minutes walked per day | 78.4±39.3 | 69.9±49.8 | 56.9±41.5 | 40.8±29.8*** | 61.2±44.2 |
Notes: Data are presented as mean ± SD or n (%).
*
Differences in age were significant for the comparison between CAT 0–10 and CAT 21–30, p<0.05,
**
p<0.01,
***
p<0.001 (Fisher’s test or ANOVA).
Abbreviations: ANOVA, analysis of variance; BDI, Beck Depression Inventory; BODEx, body mass index, airflow obstruction, dyspnea, and exacerbations; CAT, COPD assessment test; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; MMSE, Mini-Mental State Examination.