Occupational exposure to vapor, gas, dust, or fumes and chronic airflow limitation, COPD, and emphysema: the Swedish CArdioPulmonary BioImage Study (SCAPIS pilot)

Figures & data

Table 1 Descriptive data regarding occupational exposure to vapor, gas, dust, or fumes (VGDF), smoking, lung function, gender, and body mass index (BMI) in relation, and various definitions of airflow limitation, chronic airflow limitation, COPD, and emphysema

Variables	Different definitions of outcomes
	Control population N=747	Airflow limitationa N=212	Chronic airflow limitation (GOLD)b N=105	Chronic airflow limitation (LLN)c N=100	COPDd N=50	Physician-diagnosed COPD/emphysemae N=25	Emphysemaf N=98
Age, years	56.9 (4.3)	58.1 (4.4)	58.7 (4.2)	58.1 (4.3)	58.9 (4.0)	57.3 (4.4)	58.1 (4.5)
Males	371 (49.7%)	96 (45.3%)	60 (57.1%)	57 (57.0%)	31 (62%)	14 (56%)	55 (56.1%)
BMI, kg/m^2	27.3 (4.3)	27.1 (5.0)	27.2 (5.1)	27.2 (5.4)	27.1 (4.5)	28.4 (6.4)	26.2 (4.4)
Never-smokers	370 (49.5%)	59 (27.8%)	21 (20.0%)	20 (20.0%)	9 (18.0%)	5 (20%)	6 (6.0%)
Former smokers	282 (37.8%)	94 (44.3%)	43 (41.0%)	41 (41.0%)	22 (44.0%)	10 (40%)	34 (34.7%)
Current smokers	95 (12.7%)	59 (27.8%)	41 (39.1%)	39 (39.0%)	19 (38.0%)	10 (40%)	58 (59.2%)
Pack-years	7.4 (12.1)	16.0 (19.3)	21.6 (23.1)	20.6 (2.3)	23.4 (27.1)	23.3 (17.8)	27.8 (28.7)
Occupational exposure to VGDF	206 (27.6%)	90 (42.5%)	46 (43.8%)	42 (42.0%)	29 (58.0%)	16 (64%)	50 (51.0%)
FEV1, % predicted	103.5 (22.2)	90.2 (23.7)	83.1 (22.2)	86.3 (25.0)	80.4 (25.6)	73.8 (19.9)	87.2 (21.7)
FVC, % predicted	100.8 (23.4)	101.7 (25.2)	100.6 (24.4)	104.7 (26.6)	99.8 (26.9)	84.5 (17.7)	94.8 (22.1)
FEV1/FVC, %	80.7 (4.1)	69.3 (7.0)	64.3 (6.0)	64.1 (6.1)	62.4 (7.7)	68.2 (12.4)	71.9 (9.1)

Notes: Categories overlap and are not mutually exclusive. SD is given in parentheses unless otherwise indicated.

a Airflow limitation was defined as an FEV₁/FVC ratio <0.7 before bronchodilation.

b Chronic airflow limitation (GOLD) was defined as an FEV₁/FVC ratio <0.7 after bronchodilation.

c Chronic airflow limitation (LLN) was defined as an FEV₁/FVC ratio after bronchodilation below the lower limit of the normal.

d COPD was defined as chronic airflow limitation (GOLD) in combination with dyspnea, wheezing, or chronic bronchitis.

e Physician-diagnosed COPD/emphysema was defined as an affirmative answer to “Have you ever had chronic obstructive pulmonary disease or emphysema diagnosed by a physician?”

f Emphysema was categorized according to CT findings of at least mild emphysema in any zone.

Abbreviations: FEV₁, forced expiratory volume in 1 s; FVC, forced vital capacity; CT, computed tomography; LLN, lower limit of normal.

Table 2 Associations between occupational exposure to vapor, gas, dust, and fumes (VGDF) and smoking, and various definitions of airflow limitation, chronic airflow limitation, COPD, and emphysema among all subjects and stratified by gender and smoking

Independent variables	Dependent variables (outcomes)
	Airflow limitationa N=212	Chronic airflow limitation (GOLD)b N=105	Chronic airflow limitation (LLN)c N=100	COPDd N=50	Physician-diagnosed COPD/emphysemae N=25	Emphysemaf N=98
All subjects
Occupational exposure to VGDF	1.8 (1.3–2.5)	1.5 (0.95–2.5)	1.4 (0.8–2.2)	2.7 (1.4–5.1)	3.5 (1.4–8.6)	1.8 (1.1–3.1)
Current smoking	2.1 (1.3–3.6)	3.6 (1.8–7.2)	3.8 (1.9–7.6)	4.0 (1.5–10.4)	2.4 (0.7–8.9)	15.4 (5.9–40.2)
Former smoking	1.3 (0.8–2.0)	1.3 (0.7–2.4)	1.4 (0.7–2.7)	1.4 (0.6–3.5)	0.9 (0.2–3.4)	2.8 (1.1–7.3)
Males
Occupational exposure to VGDF	2.0 (1.2–3.3)	2.1 (1.1–3.9)	1.9 (1.04–3.6)	2.8 (1.2–6.4)	6.5 (1.4–13.9)	2.0 (1.02–4.1)
Females
Occupational exposure to VGDF	1.6 (0.97–2.7)	0.9 (0.4–2.2)	0.8 (0.3–1.9)	2.7 (0.9–7.8)	2.0 (0.5–7.9)	1.9 (0.8–4.5)

Notes: Categories overlap and are not mutually exclusive. Odds ratios with 95% CI are from logistic regression models adjusted for age and pack-years.

a Airflow limitation was defined as an FEV₁/FVC ratio <0.7 before bronchodilation.

b Chronic airflow limitation (GOLD) was defined as an FEV₁/FVC ratio <0.7 after bronchodilation.

c Chronic airflow limitation (LLN) was defined as an FEV₁/FVC ratio after bronchodilation below the lower limit of the normal.

d COPD was defined as chronic airflow limitation (GOLD) in combination with dyspnea, wheezing, or chronic bronchitis.

e Physician-diagnosed COPD/emphysema was defined as an affirmative answer to “Have you ever had chronic obstructive pulmonary disease or emphysema diagnosed by a physician?”.

f Emphysema was categorized according to CT findings of at least mild emphysema in any zone.

Abbreviations: FEV₁, forced expiratory volume in 1 s; FVC, forced vital capacity; CT, computed tomography; LLN, lower limit of normal.

Table 3 Occupational burden, expressed as population-attributable fraction (PAF), of airflow limitation, chronic airflow limitation, COPD, physician-diagnosed COPD/emphysema, and emphysema among all subjects and according to gender, with 95% CI

	Airflow limitationa	Chronic airflow limitation (GOLD)b	Chronic airflow limitation (LLN)c	COPDd	Physician-diagnosed COPD/emphysemae	Emphysemaf
All	0.19 (95% CI 0.10–0.26)	(0.15)	(0.15)	0.37 (95% CI 0.23–0.47)	0.46 (95% CI 0.12–0.57)	0.23 (95% CI 0.05–0.35)
Males	0.30 (95% CI 0.10–0.42)	0.19 (95% CI 0.10–0.39)	0.19 (95% CI 0.10–0.38)	0.46 (95% CI 0.12–0.60)	0.73 (95% CI 0.34–0.80)	0.34 (95% CI 0.01–0.51)
Females	(0.09)	(0.08)	(0.07)	(0.23)	(0.18)	(0.27)

Notes: PAF values in brackets are calculated from odds ratios without statistical significance.

a Airflow limitation was defined as an FEV₁/FVC ratio <0.7 before bronchodilation.

b Chronic airflow limitation (GOLD) was defined as an FEV₁/FVC ratio <0.7 after bronchodilation.

c Chronic airflow limitation (LLN) was defined as an FEV₁/FVC ratio after bronchodilation below the lower limit of the normal.

d COPD was defined as chronic airflow limitation (GOLD) in combination with dyspnea, wheezing, or chronic bronchitis.

e Physician-diagnosed COPD/emphysema was defined as an affirmative answer to “Have you ever had chronic obstructive pulmonary disease or emphysema diagnosed by a physician?”

f Emphysema was categorized according to CT findings of at least mild emphysema in any zone.

Abbreviations: FEV₁, forced expiratory volume in 1 s; FVC, forced vital capacity; CT, computed tomography; LLN, lower limit of normal.