Table 2. Demographic and baseline characteristics of asthma and COPD phenotype groups.
| Asthma predominant ACOS (n=94) | COPD predominant ACOS (n=129) | p-value | |
|---|---|---|---|
| Age, yr | 63.8±10.1 | 68.2±8.6 | 0.001 |
| Male sex | 57 (59.6) | 118 (91.5) | <0.001 |
| Smoking status | |||
| Pack-years | 19.1±25.1 | 45.1±37.8 | <0.001 |
| Current/Ex-/Never smoker | 23 (24.5)/37 (39.4)/34 (36.2) | 49 (38.0)/70 (54.3)/10 (7.8) | <0.001 |
| Age at symptom onset, yr | 48.7±14.7 | 56.0±14.6 | <0.001 |
| Duration of treatment, yr | 8.0±6.3 | 7.4±7.2 | 0.518 |
| Asthma diagnosis before age 40 | 17 (18.1) | 23 (17.8) | 1.000 |
| Other allergic disease | 30 (31.9) | 24 (18.6) | 0.027 |
| Post-bronchodilator FEV1, % predicted | 64.1±11.2 | 56.2±14.4 | <0.001 |
| Post-bronchodilator FEV1/FVC, % | 56.3±9.5 | 47.9±11.2 | <0.001 |
| Change in FEV1, mL | 386.0±240.4 | 347.3±165.9 | 0.198 |
| Change in FEV1, % | 25.8±15.8 | 26.3±16.7 | 0.850 |
| Diagnosis of airflow variability | |||
| Immediate BDR | 75 (79.8) | 109 (84.5) | 0.071 |
| >20% FEV1 after treatment | 24 (27.0) | 17 (13.5) | 0.046 |
| PEFR variability | 14 (14.9) | 31 (24.0) | 0.114 |
| Methacholine provocation test | 8 (8.5) | 2 (1.6) | 0.019 |
| Patient reported outcome | |||
| ACT score | 17.9±6.4 | 19.3±5.0 | 0.080 |
| CAT score | 12.4±8.2 | 13.5±9.2 | 0.374 |
| PHQ-9 score | 3.7±4.9 | 3.6±4.4 | 0.888 |
| Comorbidity | |||
| Rhinosinusitis | 14 (14.9) | 9 (7.0) | 0.074 |
| Gastroesophageal reflux | 11 (11.7) | 17 (13.2) | 0.839 |
| Hypertension | 32 (34.0) | 54 (41.9) | 0.266 |
| Ischemic heart disease | 5 (5.3) | 18 (14.0) | 0.045 |
| Heart failure | 3 (3.2) | 10 (7.8) | 0.246 |
| Arrhythmia | 3 (3.2) | 8 (6.2) | 0.364 |
| Diabetes mellitus | 9 (9.6) | 24 (18.6) | 0.085 |
| Osteoporosis | 16 (17.0) | 11 (8.5) | 0.063 |
| Aspirin sensitivity | 5 (5.3) | 3 (2.3) | 0.286 |
| Depression | 11 (11.7) | 13 (10.1) | 0.827 |
| Medication | |||
| ICS inhaler | 7 (7.4) | 2 (1.6) | 0.039 |
| ICS+LABA combination inhaler | 87 (91.6) | 87 (68) | <0.001 |
| LAMA inhaler | 27 (28.7) | 93 (72.1) | <0.001 |
| LABA inhaler | 1 (1.1) | 13 (10.1) | 0.005 |
| Triple therapy (LAMA+ICS+LABA) | 26 (27.7) | 62 (48.1) | 0.002 |
| Leukotriene receptor antagonist | 55 (58.5) | 17 (13.2) | <0.001 |
| Oral theophylline | 22 (23.4) | 47 (36.4) | 0.040 |
| Oral steroid | 8 (8.5) | 10 (7.8) | 0.489 |
| Inhaler compliance >75% | 83 (87.4) | 114 (89.1) | 0.833 |
| Total systemic steroid/6 mo* | 233.3±511.9 | 70.4±207.0 | 0.004 |
Values are presented as mean±SD or number (%) unless otherwise indicated.
*The amount of total systemic steroid used for the last 6 months is described as the equivalent dose of prednisolone.
COPD: chronic obstructive pulmonary disease; ACOS: asthma-COPD overlap syndrome; FEV1: forced expiratory volume in 1 second; FVC: forced vital capacity; BDR: bronchodilator response; PEFR: peak expiratory flow rate; ACT: asthma control test; CAT: COPD Assessment Test; PHQ-9: Patient Health Questionnaire; ICS: inhaled corticosteroid; LABA: long acting β2 agonist; LAMA: long acting muscarinic antagonist.