Combination therapy of inhaled steroids and long-acting beta2-agonists in asthma–COPD overlap syndrome

Figures & data

Table 1 Baseline characteristics of ACOS and COPD-alone patients

	ACOS (N=45)	COPD alone (N=107)	P-value
Age, years	64 (61–70)	68 (61–71)	0.440
Male (n)	44 (97.8)	104 (97.2)	1.000
Body mass index, kg/m^2	23.9 (22.3–25.6)	23.1 (20.4–25.4)	0.131
Smoking status
Current smoker	17 (37.8)	44 (41.1)	0.721
Pack-years	44.0 (36.6–55.0)	45.0 (30.0–55.0)	0.729
Charlson comorbidity score	1.0 (1.0–1.0)	1.0 (1.0–1.0)	0.684
mMRC dyspnea score	1.0 (1.0–2.0)	1.0 (1.0–2.0)	0.366
Severity of airflow limitation
Severe to very severe	17 (37.8)	38 (35.5)	0.854
Pulmonary function test
FVC, L	3.34 (2.62–3.66)	3.25 (2.65–3.87)	0.715
FVC, % predicted	82.0 (73.2–95.5)	87.0 (73.0–99.0)	0.323
FEV1, L	1.53 (1.19–1.81)	1.52 (1.09–1.91)	0.569
FEV1, % predicted	54.9 (44.5–65.5)	56.0 (43.0–72.0)	0.339
TLC, L	6.17 (5.62–7.11)	6.78 (5.63–7.48)	0.319
RV, L	3.03 (2.41–3.51)	2.93 (2.15–4.00)	0.192
IC, L	2.05 (1.67–2.39)	1.92 (1.56–2.52)	0.718
DLCO, %	85.0 (66.0–96.0)	83.0 (71.0–101.3)	0.848
CT determined
Emphysema index, %	15.6 (7.6–27.0)	15.7 (7.3–33.5)	0.240
Mean wall area, %	66.5 (62.4–70.2)	65.7 (62.0–69.4)	0.545
Peripheral eosinophil count
Eosinophil count, /μL	213.3 (134.2–339.5)	197.1 (108.3–360.4)	0.251
Eosinophil count ≥260, %	20 (44.4)	43 (40.2)	0.719

Note: The data are presented as number (%) or as median and interquartile range.

Abbreviations: ACOS, asthma–COPD overlap syndrome; COPD, chronic obstructive pulmonary disease; CT, computed tomography; DL_CO, diffusing capacity for carbon monoxide; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; IC, inspiratory capacity; mMRC, modified Medical Research Council; RV, residual volume; TLC, total lung capacity.

Table 2 Changes of pulmonary function and symptom score, and the rate of acute exacerbation after 3 months of treatment in ACOS and COPD-alone patients

	ACOS (N=45)	COPD alone (N=107)	P-value
Changes of pulmonary function and symptom score
Δ FEV1, mL	240.2±33.5	124.6±19.8	0.002
Δ FVC, mL	304.8±59.0	150.2±38.1	0.030
Δ TLC, mL	435.3±264.0	888.3±247.7	0.213
Δ RV, mL	−93.3±156.0	102.8±129.5	0.380
Δ IC, mL	166.9±84.9	141.5±62.6	0.820
Δ mMRC	−0.05±0.17	−0.39±0.08	0.126
Acute exacerbation, %	15.0	12.2	0.719

Note: The baseline PFT data are presented as median and interquartile range, and lung function changes are presented as mean ± standard error.

Abbreviations: ACOS, asthma–COPD overlap syndrome; COPD, chronic obstructive pulmonary disease; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; IC, inspiratory capacity; mMRC, modified Medical Research Council; RV, residual volume; TLC, total lung capacity.

Figure 1 Comparison of change in FEV₁ between ACOS and COPD-alone patients.

Note: The ACOS group showed a significantly greater increase in FEV₁ than the COPD-alone group in patients with mild-to-moderate airflow limitation but not in patients with severe to very severe airflow limitation. (A) ΔFEV₁ (mL); (B) FEV₁ responders (%).
Abbreviations: ACOS, asthma–COPD overlap syndrome; COPD, chronic obstructive pulmonary disease; FEV₁, forced expiratory volume in 1 second.

Figure 2 Independent associations of ACOS with FEV₁ increase and FEV₁ responders.

Note: The presence of ACOS was independently associated with FEV₁ increase and FEV₁ responders compared with COPD alone.
Abbreviations: ACOS, asthma–COPD overlap syndrome; CI, confidence interval; COPD, chronic obstructive pulmonary disease; FEV₁, forced expiratory volume in 1 second.

Figure S1 Comparison of change in FEV₁ (mL) between ACOS and COPD-alone patients.

Note: ACOS patients, classified with other criteria¹ proposed by experts, showed a significantly greater increase in FEV₁ than those with COPD alone.

Abbreviations: ACOS, asthma–COPD overlap syndrome; COPD, chronic obstructive pulmonary disease; FEV₁, forced expiratory volume in 1 second.

Table S1 Multiple logistic regression analysis of clinical factors associated with FEV₁ (mL) change after 3 months of ICS/LABA treatment

Variables	FEV1 (mL) change			FEV1 responder*
	β coefficient	95% CI	P-value	OR	95% CI	P-value
ACOS	95.82	21.383–170.258	0.012	3.352	1.409–7.972	0.006
Age	−6.232	−10.894–1.570	0.009	0.921	0.868–0.977	0.006
BMI	11.680	0.380–22.979	0.043	1.033	0.908–1.176	0.621
Smoking status, pack-years	−0.226	−1.707–1.256	0.764	0.995	0.977–1.013	0.605
mMRC	24.973	−10.491–60.437	0.166	1.217	0.798–1.857	0.362
Baseline FEV1	−122.788	−198.469–47.107	0.002	0.223	0.083–0.600	0.003
Emphysema index on CT	−3.607	−6.257–0.957	0.008	0.979	0.948–1.010	0.177
Blood eosinophil count >260/L	72.931	5.758–140.103	0.034	3.292	1.476–7.346	0.004

Note:

* Defined by an FEV₁ improvement of at least 12% and 200 mL from baseline after 3 months of combined treatment with ICS/LABA.

Abbreviations: ACOS, asthma–COPD overlap syndrome; BMI, body mass index; CI, confidence interval; COPD, chronic obstructive pulmonary disease; CT, computed tomography; ICS, inhaled corticosteroid; FEV₁, forced expiratory volume in 1 second; LABA, long-acting beta2-agonist; mMRC, modified Medical Research Council; OR, odds ratio.