Background
Methods
Study participants
Clinical assessments
Passive and active smoking exposures
Carbon content of macrophages
Inflammatory phenotype
Occupational exposures
Statistical methods
Results
Count/Median | Percentage/IQR (25th-75thpercentile) | Count N | |
---|---|---|---|
Age (years) | 59.9 | 49.2 – 65.7 | 66 |
Female | 34 | 52% | 66 |
Age of asthma diagnosis (years) | 18.5 | 6.0 – 42.0 | 66 |
Currently Employed | 43 | 65% | 66 |
Ex-smoker | 19 | 29% | 66 |
Ex-smoker Pack years | 1.7 | 0.50 – 5.00 | 19 |
Atopic asthma | 50 | 76% | 66 |
Past 12 months unscheduled doctors visit | 38 | 58% | 66 |
Past 12 months oral corticosteroids | 28 | 42% | 66 |
Past 12 months hospitalisation | 5 | 8% | 66 |
Asthma control score (ACQ) | 1.41 | 1.00 – 2.14 | 66 |
Quality of Life Total Score | 5.71 | 4.81 – 6.44 | 66 |
FEV1% predicted | 69.4 | 53.0 – 82.4 | 66 |
FEV1/FVC | 66.7 | 58.0 – 76.0 | 66 |
ICS dose/1000 (mg/day)†
| 2 | 1 – 2 | 65 |
PD15
‡
| 4.84 | 1.39 – 14.26 | 42 |
Dose response slope*
| 2.59 | 0.76 – 5.59 | 53 |
Active and passive smoking exposures
Never smoked | Ex-smoker | P | |||
---|---|---|---|---|---|
N = 47 | N = 19 | ||||
Median | IQR | ||||
Smoking (pack-years) | 1.70 | 0.5 – 5.00 | |||
Passive smoking at home
| |||||
Lives with one or more smokers | 4 | 9% | 5 | 26% | 0.108 |
Smoking not allowed in home | 12 | 23% | 1 | 5% | 0.156 |
Smoking allowed inside | 2 | 4% | 5 | 26% | 0.018 |
Smoking allowed outside | 34 | 72% | 13 | 68% | 0.770 |
Passive smoking elsewhere
| |||||
No time with smokers | 18 | 38% | 4 | 21% | 0.252 |
Spends time indoors smokers | 6 | 13% | 3 | 16% | 0.709 |
Spends time outdoors smokers | 22 | 47% | 12 | 63% | 0.283 |
Median
|
IQR
|
Median
|
IQR
| ||
Smoking biomarkers
| |||||
eCO (ppm) | 2 | 1 - 3 | 2 | 1 – 3 | 0.751 |
NicAlert™ | 1 | 1 - 1 | 1 | 0 – 2 | 0.441 |
Occupational exposures
Level of risk | Agents | Total N | N | Occupations |
---|---|---|---|---|
High risk
|
High molecular weight
| |||
Animals | 1 | 1 | Dairy and livestock producers | |
Latex | 2 | 1 | Nursing and midwifery professionals | |
1 | Institution-based personal care workers | |||
Bioaerosols | 2 | 1 | Dairy and livestock producers | |
1 | Machine-tool operators | |||
Total number with a high molecular weight exposure | 4* | |||
Low molecular weight
| ||||
Highly reactive chemicals | 3 | 1 | Biologists, botanists, zoologists and related professionals | |
1 | Institution-based personal care workers | |||
1 | Helpers/cleaners in offices, hotels etc. | |||
Industrial cleaning products | 2 | 1 | Institution-based personal care workers | |
1 | Helpers/cleaners in offices, hotels etc. | |||
Wood dusts | 1 | 1 | Carpenters and joiners | |
Metal sensitizers | 2 | 1 | Tool-makers and related workers | |
1 | Machine-tool operators | |||
Total number with a low molecular weight exposure | 6* | |||
Mixed environments or agents
| ||||
Metal working fluids | 2 | 1 | Tool-makers and related workers | |
1 | Machine-tool operators | |||
Agricultural | 1 | 1 | Dairy and livestock producers | |
Textiles | 1 | 1 | Tailors, dressmakers and hatters | |
High irritant peaks | 2 | 2 | Police officers | |
Total number with exposure to mixed environments or agents | 6* | |||
Total number with a high risk exposure
|
11* | |||
Low risk
|
Possible exposure to other respiratory hazards
| |||
Irritants, but not high peaks | 3 | 1 | Carpenters and joiners | |
1 | Mining-plant operators | |||
1 | Helpers/cleaners in offices, hotels etc. | |||
Motor vehicle exhaust fumes | 9 | 2 | Police officers | |
1 | Motor mechanics and fitters | |||
1 | Railway brakers, signallers and shunters | |||
3 | Car, taxi and van drivers | |||
1 | Bus and tram drivers | |||
1 | Lifting-truck operators | |||
Environmental tobacco smoke | 1 | 1 | Waiters, waitresses and bartenders | |
Total number with exposure to other respiratory hazards | 13* | |||
Total number with a low risk exposure
|
9
| |||
No risk
|
Total number with no exposure to any respiratory hazard
|
46
|
Diagnosis age 30+, unexposed | Diagnosis age 30+, exposed | Diagnosis age <30, unexposed | Diagnosis age <30, exposed | |||||
---|---|---|---|---|---|---|---|---|
Observed first visit
| N = 14 | N = 12 | N = 32 | N = 8 | ||||
Age | 14 | 63 (60-69) | 12 | 64 (62-69) | 32 | 53 (44-63) | 8 | 46 (37-52) |
Female | 14 | 9 (64%) | 12 | 4 (33%) | 32 | 19 (59%) | 8 | 2 (25%) |
Currently Employed | 14 | 6 (43%) | 12 | 6 (50%) | 32 | 24 (75%) | 8 | 7 (88%) |
Years at work | 14 | 30 (30-35) | 12 | 30 (20-30) | 32 | 25 (19-33) | 8 | 25 (15-26) |
Ex-smoker | 14 | 5 (36%) | 12 | 2 (17%)** | 32 | 7 (22%) | 8 | 5 (63%)** |
Smoking at home | 14 | 2 (14%) | 12 | 2 (17%) | 32 | 3 (9%) | 8 | 0 (0%) |
Smoky places | 14 | 7 (50%) | 11 | 8 (73%) | 32 | 20 (63%) | 8 | 8 (100%)** X
|
Atopic | 14 | 6 (43%) | 12 | 9 (75%) | 32 | 28 (88%) | 8 | 7 (88%)XX AA
|
ICS dose/1000 | 14 | 2 (1.6-2.0) | 12 | 2 (0.9-2.0) | 31 | 2 (0.6-2.0) | 8 | 2 (1.0-2.0) |
%Macrophages w carbon inclusion | 1 | 30 | 5 | 46 (46-48) | 7 | 30 (20-52) | 1 | 42 |
# Carbon inclusions/macrophage | 1 | 2 | 5 | 4 (4.0-5.0) | 7 | 3 (2-6) | 1 | 4 |
Total number Carbon inclusions | 1 | 57 | 5 | 184 (160-212) | 7 | 107 (27-224) | 1 | 186 |
Obs. multiple visits
|
N = 22
|
N = 20
|
N = 71
|
N = 14
| ||||
FEV1% predicted | 17 | 82 (59-88) | 16 | 75 (64-84) | 46 | 63 (48-79) | 10 | 74 (67-83)X AA
|
FEV1/FVC | 17 | 76 (64-80) | 16 | 71 (67-77) | 46 | 64 (56-69) | 10 | 69 (63-71)XX AA
|
PD15
| 10 | 15 (12-29) | 5 | 21 (19-34) | 32 | 5 (1.1-8.6) | 8 | 2 (1.3-6.5)XX AA
|
Dose response slope | 14 | 1 (0.5-2.2) | 11 | 0 (0.2-0.8) | 41 | 3 (1.2-11.5) | 9 | 6 (2.1-8.6)XX AA
|
Total cell # ×106/mL | 21 | 3 (2.1-3.6) | 20 | 6 (2.7-10.6) | 69 | 3 (2.1-7.8) | 14 | 3 (1.8-7.2) |
Macrophages, % | 22 | 51 (28-72) | 20 | 28 (15-51) | 71 | 44 (20-61) | 14 | 44 (28-52) |
Neutrophils, % | 22 | 27 (14-40) | 20 | 47 (37-74) | 71 | 42 (27-72) | 14 | 51 (36-67)XX
|
Lymphocytes, % | 22 | 1 (0.0-2.0) | 20 | 0 (0.0-1.1) | 71 | 1 (0.3-2.0) | 14 | 0 (0.0-1.3) |
Eosinophils, % | 22 | 1 (0.3-3.3) | 20 | 2 (0.9-9.9) | 71 | 1 (0.3-2.8) | 14 | 1 (0.3-1.8) |
Col. epithelial cells, % | 22 | 6 (1.5-12.8) | 20 | 3 (0.8-7.0) | 71 | 3 (1.5-5.9) | 14 | 4 (2.5-7.3) |
Squamous cells, % | 22 | 5 (1.5-11.3) | 20 | 2 (0.9-4.4) | 71 | 3 (1.0-6.1) | 14 | 5 (1.2-9.5) |