Table 1.
Baseline Characteristics of COPD Patients with Different BMIs (n=1644)
| Characteristics | Underweight (n=198) | Normal Weight (n=757) | Overweight (n=460) | Obese (n=229) | P value |
|---|---|---|---|---|---|
| Sex, male, n (%) | 174 (87.9) | 653 (86.3) | 378 (82.2) | 179 (78.2) | 0.13 |
| Age, yr | 67.0±9.2 | 66.4±8.8 | 64.9±8.7 | 62.6±10.2 | 0.01 |
| Neck Circumference, cm | 35.1±2.7 | 37.4±2.6 | 39.5±3.0 | 42.3±4.3 | <0.01 |
| Degree of education, n (%) | 0.03 | ||||
| Under college | 182 (92.0) | 662 (87.5) | 385 (83.7) | 198 (86.5) | |
| Above college | 16 (8.0) | 95 (12.5) | 75 (16.3) | 31 (13.5) | |
| Economic status, n (%) | 0.51 | ||||
| Higher income | 0 (0.0) | 12 (1.6) | 8 (1.7) | 2 (0.9) | |
| Middle income | 19 (9.6) | 74 (9.8) | 48 (10.4) | 18 (7.9) | |
| Lower income | 179 (90.4) | 671 (88.6) | 404 (87.9) | 209 (91.2) | |
| Smoking status, n (%) | <0.01 | ||||
| Never | 35 (17.7) | 134 (17.7) | 105 (22.8) | 51 (22.3) | |
| Former | 50 (25.3) | 188 (24.8) | 130 (28.3) | 75 (32.7) | |
| Current | 113 (57.0) | 435 (57.5) | 225 (48.9) | 103 (45.0) | |
| Alcohol consumption, n (%) | 0.05 | ||||
| Never | 129 (65.2) | 461 (60.9) | 262 (57.0) | 136 (59.4) | |
| Former | 20 (10.1) | 48 (6.3) | 49 (10.6) | 21 (9.2) | |
| Current | 49 (24.7) | 248 (32.8) | 149 (32.4) | 72 (31.4) | |
| FVC, L | 2.35±0.81 | 2.60±0.88 | 2.88±0.97 | 2.80±1.02 | <0.01 |
| FEV1, L | 1.05±0.57 | 1.29±0.62 | 1.56±0.72 | 1.67±0.74 | <0.01 |
| FEV1% Predicted | 41.65±18.71 | 50.75±22.10 | 59.22±23.23 | 62.05±22.20 | <0.01 |
| FEV1/FVC% Predicted | 44.95±12.67 | 49.14±12.73 | 55.75±12.16 | 58.88±9.93 | <0.01 |
| Severity of COPD, n (%) | <0.01 | ||||
| GOLD 1 | 12 (6.1) | 96 (12.7) | 105 (22.8) | 53 (23.1) | |
| GOLD 2 | 38 (19.2) | 241 (31.8) | 172 (37.5) | 103 (45.0) | |
| GOLD 3 | 95 (48.0) | 286 (37.8) | 140 (30.4) | 60 (26.2) | |
| GOLD 4 | 53 (26.7) | 134 (17.7) | 43 (9.3) | 13 (5.7) | |
| mMRC dyspnea scale | 2.02±0.96 | 1.79±0.96 | 1.58±0.97 | 1.55±1.00 | <0.01 |
| Hypertension, n (%) | 43 (21.7) | 257 (33.9) | 218 (47.4) | 147 (64.2) | <0.01 |
| Diabetes mellitus, n (%) | 7 (3.5) | 60 (7.9) | 69 (15.0) | 51 (22.3) | <0.01 |
| Cardiovascular disease, n (%) | 34 (17.2) | 163 (21.5) | 131 (28.5) | 1 (39.7) | <0.01 |
| Cerebrovascular disease, n (%) | 10 (5.1) | 73 (9.6) | 50 (10.9) | 24 (10.5) | 0.12 |
| Osteoporosis, n (%) | 3 (1.5) | 24 (3.2) | 14 (3.0) | 4 (1.7) | 0.45 |
| COPD history, month, median (Q1,Q3) | 60 (24, 120) | 54 (14, 120) | 36 (2, 84) | 12 (0, 60) | <0.01 |
| `Events in previous year | |||||
| Acute exacerbation, n (%) | 142 (71.7) | 441 (58.3) | 250 (54.3) | 101 (44.1) | <0.01 |
| NIV, n (%) | 11 (5.6) | 51 (6.7) | 24 (5.2) | 23 (10.0) | 0.10 |
| Blood cell analysis | |||||
| WBC, ×109/L | 7.35±3.20 | 7.52±2.95 | 7.48±2.48 | 7.39±2.38 | 0.86 |
| RBC, ×1012/L | 4.30±0.56 | 4.50±0.61 | 4.56±0.54 | 4.73±0.59 | <0.01 |
| HB, g | 129.2±16.16 | 136.7±17.5 | 140.2±16.17 | 143.0±17.4 | <0.01 |
| PLT, ×109/L | 218.02±83.16 | 221.50±77.22 | 211.85±69.49 | 216.54±53.92 | 0.07 |
Notes: Continuous variables which are obviously skewed were presented as median (Q1, Q3), other continuous variables were described as means ±SD. Categorical variables were expressed as percentages. P value for the difference between the groups.
Abbreviations: BMI, body mass index; COPD, chronic obstructive pulmonary disease; FVC, forced vital capacity; FEV1, forced expiratory volume in the first second; GOLD 1, FEV1 ≥80% predicted; GOLD 2, FEV1=50–79% predicted; GOLD 3, FEV1=30–49% predicted; GOLD 4, FEV1 <30% predicted; mMRC, modified Medical Research Council; NIV, non-invasive ventilation; WBC, white blood cells; RBC, red blood cells; HB, hemoglobin; PLT, platelets.