Background
Methods
Study population and mattress dust sample selection
Selection and analysis of microbial agents
Home and personal characteristics
Current asthma symptoms and lung function parameters
Statistical analysis
Ethical approval
Results
Study population and home characteristics
n/N (%) | |
---|---|
Females
| 486/956 (51%) |
Age (in years, median) | 44 years |
Education (age, median) | at 20 years |
Asthma Score, past 12 months
| |
0 (no symptoms) | 603/949 (64%) |
1 | 208/949 (22%) |
2 | 95/949 (10%) |
3 | 20/949 (2%) |
4 | 14/949 (2%) |
5 | 9/949 (1%) |
FEV
1
(in milliliter, 1st second, median) | 3470 ml/s |
FVC (in milliliter, median) | 4230 ml |
Observed dampness and mould in the bedroom
| |
Damp patches on the walls/ceilings in the bedroom | 71/904 (8%) |
Mould or mildew on the walls/ceilings in the bedroom | 47/904 (5%) |
Reported condensation on the bedroom windows (winter) | 208/899 (23%) |
Self-reported signs of dampness and mould at home
| |
Wet or damp spots in the last 12 months | 197/950 (21%) |
Mould in the home | |
Current | 150/950 (16%) |
Ever before | 72/950 (8%) |
Water damage in the home | |
Current | 94/930 (10%) |
Ever before | 189/930 (20%) |
Exposure to tobacco smoke
| |
Current smoking | 299/954 (31%) |
Former smoking | 253/954 (27%) |
Never smoked | 402/954 (42%) |
Cat in the home
| |
Cat in the home | 182/955 (19%) |
Cat in the home and allowed in the bedroom | 132/955 (14%) |
Dog in the home
| |
Dog in the home | 156/955 (16%) |
Dog in the home and allowed in the bedroom | 82/955 (9%) |
Season of dust sampling
| |
Winter | 227/907 (25%) |
Spring | 256/907 (28%) |
Summer | 129/209 (14%) |
Autumn | 295/907 (33%) |
Bed in the living room
| 54/955 (6%) |
Distribution and correlation of microbial compounds and species throughout Europe
C. herbarumDNA | Pen./Asp./Paec.DNA | (1,3)-ß-D-glucan | Mycobacterium spp.DNA | Muramic acid | Gram-pos. bacteria DNA | Gram-neg. bacteria DNA | Endotoxin | |
---|---|---|---|---|---|---|---|---|
C. herbarum
DNA
| ||||||||
Pen./Asp./Paec.
DNA
|
0.14***
| |||||||
(1,3)-ß-D-glucan
|
0.12***
|
0.35***
| ||||||
Mycobacterium spp.
DNA
|
0.49***
|
0.28***
|
0.25***
| |||||
Muramic acid
|
0
|
0.17***
|
0.22***
|
0.25***
| ||||
Gram-pos. bacteria DNA
|
0.32***
|
0.24***
|
0
|
0.45***
|
0.43***
| |||
Gram-neg. bacteria DNA
|
0.45***
|
0.28***
|
0.12***
|
0.55***
|
0.31***
|
0.82***
|
Predictors for levels of microbial agents in mattress dust
Home, personal and environmental characteristics | |||||||
---|---|---|---|---|---|---|---|
Characteristics | C. herbarumDNA MR (95% CI) | Pen./Asp./Paec.DNA MR (95% CI) | (1,3)-ß-D-glucan MR (95% CI) | Mycobac. spp.DNA MR (95% CI) | Muramic acid DNA MR (95% CI) | Gram-pos bac DNA MR (95% CI) | Gram-neg bacDNA MR (95% CI) |
Damp patches in the bedroom (observed) | 1.19 (0.79-1.80) | 1.11 (0.50-2.48) | 1.02 (0.82-1.28) | 1.39 (0.90-2.14) | 1.19 (0.96-1.49) |
1.87 (1.16-3.00)
|
1.70 (1.09-2.67)
|
Visible mould in the bedroom(observed) | 1.06 (0.66-1.69) | 0.95 (0.38-2.37) | 1.23 (0.94-1.59) | 0.87 (0.53-1.43) | 0.98 (0.76-1.26) | 0.77 (0.45-1.32) | 0.77 (0.46-1.28) |
Condensation in bedroom (reported during inspection) | 0.94 (0.78-1.13) |
1.87 (1.31-2.67)
| 1.10 (0.99-1.23) | 0.92 (0.76-1.12) | 0.91 (0.83-1.01) | 0.91 (0.73-1.12) | 1.03 (0.84-1.26) |
Wet or damp spots in the last 12 months
| 1.13 (0.92-1.40) |
1.67 (1.11-2.51)
| 1.09 (0.96-1.23) | 1.15 (0.92-1.44) | 0.93 (0.83-1.05) | 0.80 (0.63-1.02) | 1.07 (0.85-1.34) |
Mould in the home: Current | 0.99 (0.78-1.24) | 1.26 (0.81-1.97) | 0.93 (0.82-1.06) | 0.92 (0.72-1.18) | 0.98 (0.86-1.11) | 0.99 (0.76-1.29) | 1.03 (0.80-1.32) |
Ever before | 0.88 (0.66-1.16) | 0.86 (0.50-1.50) | 1.06 (0.90-1.26) | 0.91 (0.67-1.22) | 1.14 (0.98-1.34) | 1.05 (0.75-1.45) | 1.06 (0.77-1.44) |
Water damage in the home: Current | 1.07 (0.83-1.39) | 0.85 (0.51-1.41) | 1.00 (0.86-1.17) | 0.95 (0.73-1.25) | 1.03 (0.90-1.18) | 1.27 (0.94-1.71) | 1.14 (0.86-1.51) |
Ever before | 0.94 (0.77-1.14) | 0.85 (0.59-1.24) | 0.97 (0.87-1.08) | 0.89 (0.72-1.09) |
1.15 (1.04-1.28)
| 0.88 (0.71-1.10) | 0.88 (0.71-1.08) |
Cat in the home
|
1.52 (1.09-2.12)
| 1.14 (0.60-2.16) | 1.10 (0.91-1.32) | 1.32 (0.94-1.87) | 1.13 (0.94-1.35) | 1.26 (0.86-1.84) | 1.08 (0.76-1.56) |
Cat also allowed in bedroom
|
1.47 (1.18-1.83)
| 0.91 (0.59-1.39) |
1.14 (1.01-1.29)
|
1.46 (1.16-1.84)
| 1.12 (0.99-1.26) | 1.17 (0.91-1.51) | 1.25 (0.98-1.59) |
Dog in the home
|
1.61 (1.22-2.14)
|
2.50 (1.44-4.31)
|
1.36 (1.16-1.61)
|
1.79 (1.33-2.41)
| 1.15 (0.99-1.34) | 1.33 (0.96-1.83) |
1.65 (1.21-2.24)
|
Dog also allowed in bedroom
|
2.31 (1.74-3.05)
| 1.34 (0.77-2.32) |
1.24 (1.06-1.45)
|
2.23 (1.66-3.01)
|
1.28 (1.09-1.49)
|
2.06 (1.49-2.85)
|
2.20 (1.61-3.01)
|
Current smoking
| 1.10 (0.92-1.31) | 0.88 (0.63-1.25) | 1.00 (0.91-1.11) | 0.92 (0.76-1.10) |
1.14 (1.03-1.25)
|
1.32 (1.08-1.62)
| 1.10 (0.90-1.33) |
Bed in living room
| 0.53 (0.07-3.82) | 1.53 (0.32-7.34) | 1.64 (0.68-3.93) | 0.30 (0.04-2.43) | 1.09 (0.37-3.19) | 0.42 (0.04-4.13) | 0.25 (0.03-2.23) |
Latitude (per 10°N)
|
1.63 (1.05-2.54)
|
0.56 (0.40-0.79)
| 0.87 (0.69-1.10) | 1.06 (0.80-1.41) |
0.74 (0.64-0.84)
| 1.22 (0.85-1.76) | 1.15 (0.78-1.68) |
SpringSeason (ref. winter) | 0.83 (0.67-1.02) | 0.83 (0.55-1.24) | 0.92 (0.82-1.04) | 0.89 (0.71-1.10) |
0.89 (0.79-0.99)
| 0.81 (0.64-1.04) | 0.80 (0.64-1.01) |
Summer |
1.80 (1.40-2.31)
| 0.80 (0.49-1.29) |
1.22 (1.06-1.41)
| 1.12 (0.86-1.46) | 1.04 (0.90-1.19) | 0.82 (0.62-1.10) | 0.84 (0.64-1.11) |
Autumn |
1.84 (1.50-2.25)
| 0.82 (0.55-1.21) |
1.16 (1.03-1.30)
| 1.01 (0.82-1.25) | 0.99 (0.88-1.10) |
0.71 (0.56-0.89)
| 0.83 (0.67-1.04) |
Association between selected home and personal characteristics with current asthma symptoms and lung function parameters
Asthma score*aMR (95% CI) | FEV1$aß (95% CI) | FVC$aß (95% CI) | ||
---|---|---|---|---|
Microbial Agents per IQR
|
C. herbarum
DNA
| 0.92 (0.78-1.09) | 20 (-30; 80) | 20 (-50; 80) |
Pen. /Asp./Paec. Variotii
DNA
| 1.07 (0.94-1.21) | -10 (-50; 30) | 10 (-30; 60) | |
(1,3)-ß-D-glucan
| 0.94 (0.81-1.10) | -10 (-100-50) | -40 (-110;30) | |
Mycobacterium spp.
DNA
| 1.08 (0.93-1.26) | 10 (-40; 50) | -20 (-80; 30) | |
Muramic acid
|
1.37 (1.17-1.61)
| 3 (-50; 50) | 0.3 (-60; 60) | |
Gram-positive bacteria DNA
| 1.07 (0.94-1.21) | -4 (-40;30) | -20 (-60; 30) | |
Gram-negative bacteria DNA
| 1.04 (0.91-1.20) | -10 (-50; 30) | -20 (-70; 30) | |
Dampness and Mould
|
Damp patches in the bedroom
| 1.40 (0.97-2.01) | -120 (-240; 2) | -120 (-240; 2) |
Visible mould in the bedroom
| 1.32 (0.84-2.07) | -100 (-240; 40) |
-140 (-280; -3)
| |
Condensation on bedroom windows
| 1.22 (0.96-1.57) |
-90 (-160; -10)
| -70 (-170; 20) | |
Dampness at home past 12 months
| 1.24 (0.97-1.59) | 4 (-80; 90) | 50 (-50; 150) | |
Mould at home
| ||||
Current
|
1.41 (1.07-1.85)
| -10 (-100; 80) | 60 (-50; 170) | |
Ever
| 1.12 (0.75-1.66) | -70 (-190; 50) | -60 (-200; 80) | |
Water damage
| ||||
Current
| 1.10 (0.77-1.56) | -10 (-120; 90) | -10 (-140; 120) | |
Ever
| 1.16 (0.90-1.51) | -10 (-90; 70) | -20 (-120; 80) | |
Home / Personal
|
Cat in the home
| 1.04 (0.66-1.66) |
140 (10; 280)
| 160 (-10; 320) |
Cat in bedroom
| 0.93 (0.68-1.27) | -3 (-100; 90) | -10 (-130; 100) | |
Dog at home
| 1.12 (0.76-1.63) | -10(-130; 100) | -60 (-200; 80) | |
Dog in bedroom
| 1.05 (0.72-1.53) | 50 (-60; 160) | 40 (-100; 180) | |
Current smoking
|
1.85 (1.44-2.36)
| -70 (-140; 1) | 0.1 (-90; 90) | |
Bed in living room
|
1.63 (1.10-2.42)
|
-230 (-390; -80)
|
-210 (-410; -10)
|