Baseline characteristics and anxiety
| COPD (n=1202) | Controls (n=302) | |||
| No anxiety (n=1024) | Anxiety (n=181) | No anxiety (n=283) | Anxiety (n=19) | |
| Age (mean years, SD) | 59 (6) | 55 (6.6)* | 59 (6.1) | 55 (6.6)† |
| Female sex (n, %) | 563 (55%) | 128 (71%)* | 107 (38%) | 10 (53%) |
| Race (white, non-Hispanic) | 698 (68%) | 112 (62%)‡ | 94 (53%) | 8 (42%) |
| Educational attainment (n, %) | ||||
| High school or less | 288 (28%) | 64 (35%)* | 39 (14%) | 3 (16%) |
| Some college | 436 (43%) | 88 (49%) | 88 (31%) | 7 (37%) |
| College degree or higher | 297 (29%) | 29 (16%) | 156 (55%) | 9 (47%) |
| Household income (n, %) | ||||
| Low income | 93 (9%) | 36 (20%)* | 8 (3%) | 1 (5%) |
| Medium income | 595 (58%) | 104 (57%) | 127 (45%) | 10 (53%) |
| High income | 252 (25%) | 24 (13%) | 126 (45%) | 7 (37%) |
| Smoking history (n, %) | ||||
| Past smoker | 565 (55%) | 79 (44%)* | 123 (43%) | 9 (47%) |
| Current smoker | 311 (30%) | 82 (45%) | 11 (4%) | 1 (5%) |
| Never smoker | 145 (14%) | 20 (11%) | 149 (53%) | 9 (47%) |
| Mean (SD) FEV1 (l) | 1.78 (0.8) | 1.88 (0.8)‡ | 2.73 (0.7) | 3.03 (0.8)‡ |
| Mean (SD) BMI (kg/m2) | 32 (8) | 32 (8) | 30 (6) | 30 (8) |
| Cardiovascular comorbidity | ||||
| Coronary artery disease | 112 (11%) | 27 (15%) | 8 (2.8%) | 0 (0%) |
| Hypertension | 551 (54%) | 106 (59%) | 112 (40%) | 6 (32%) |
| Congestive heart failure | 112 (11%) | 24 (13%) | 0 (0%) | 0 (0%) |
p Values for categorical outcomes (educational attainment, household income and smoking history) were for the overall comparison of all categories.
A minority of the cohort (8%) declined to report their income.
↵* p<0.001 for comparison of subjects with anxiety vs no anxiety.
↵† p<0.05 for comparison of subjects with anxiety vs no anxiety.
↵‡ p<0.10.
BMI, body mass index; COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 s.