Moisture damage and childhood asthma: a population-based incident case–control study

J. Pekkanen; A. Hyvärinen; U. Haverinen-Shaughnessy; M. Korppi; T. Putus; A. Nevalainen

doi:10.1183/09031936.00040806

Tables

Table 1—

Characteristics of cases and controls

	Controls	Cases
Subjects n^#	241	121
Male %	66.7	65.8
Age yrs	3.23	2.91
Father's education yrs	13.0	13.3
Mother's education yrs	14.2	14.1
Parental asthma %	9.1	20.7
Current smoking at home %	31.0	27.5
Number of siblings %
0	21.2	12.9
1	39.8	56.0
2+	38.8	31.1
No day care <1 yr %	98.3	95.0
Child has lived on a farm %	15.5	14.2
Pets currently %	48.3	28.1
Building characteristics
Single family/row house %	75.9	74.4
Basement %	17.5	11.8
Timber/log frame %	57.3	57.0
Flat roof %	14.9	8.3
Renovated %	79.2	79.0
Natural ventilation %	37.8	30.6
Condensation on windows %	33.7	40.4
Use of humidifiers %	7.5	12.7
Use of additional heating %	33.2	36.4
Age of the building yrs	24.8	26.7
Size of the building m²	105.4	105.4

Data are presented as mean, unless otherwise stated. ^#: The number of observations with nonmissing data on different characteristics ranged 220–241 among controls and 116–121 among cases.

Table 2—

Moisture-damage characteristics of the whole home and their multivariate adjusted associations with asthma

	Prevalence	Cases versus controls
Any or suspected moisture damage
No	49 (13.6)	1
Yes	310 (86.4)	0.63 (0.28–1.45)
Need for repair
1	66 (18.4)	1
2	177 (49.3)	0.66 (0.30–1.46)
3+	116 (32.4)	0.90 (0.40–2.00)
Area of damage^# m²	352 (3.33)	1.01⁺ (0.98–1.05)
Visible mould^¶
No	184 (51.3)	1
Yes	175 (48.7)	1.24 (0.73–2.11)
Mould odour^¶
No	331 (92.2)	1
Some	19 (5.3)	1.35 (0.42–4.36)
Clear	9 (2.5)	4.12 (0.65–26.01)

Data are presented as n (%) or odds ratio (95% confidence interval), unless otherwise stated. ^#: mean area of damage; ^¶: inspector’s observations; ⁺: for a 1 m² change in area of damage.

Table 3—

Moisture-damage characteristics in different areas of the home and their multivariate adjusted association with asthma

	Prevalence	Cases versus controls
Main living area
Severity of damage
No	251 (69.5)	1
Minor or major	110 (30.4)	2.24 (1.25–4.01)
Visible mould
No	327 (90.6)	1
Yes	34 (9.4)	2.59 (1.15–5.85)
Kitchen
Severity of damage
No	256 (70.9)	1
Minor or major	105 (29.1)	1.41 (0.80–2.47)
Visible mould
No	270 (74.8)	1
Yes	91 (25.2)	1.13 (0.63–2.04)
Bathroom
Severity of damage
No	102 (28.3)	1
Minor or major	122 (71.8)	0.70 (0.39–1.25)
Visible mould
No	268 (74.2)	1
Yes	93 (25.7)	0.81 (0.44–1.49)
Other interior spaces
Severity of damage
No	275 (76.2)	1
Minor or major	86 (23.8)	0.77 (0.40–1.46)
Visible mould
No	319 (88.1)	1
Yes	14 (11.9)	0.86 (0.37–2.00)

Data are presented as n (%) or odds ratio (95% confidence interval).

Table 4—

Moisture-damage characteristics in the main living area and in the child's bedroom and their multivariate adjusted association with asthma

	Prevalence	Cases versus controls
Main living area
Severity of damage
No	251 (69.5)	1
Minor	72 (19.9)	2.11 (1.06–4.21)
Major	38 (10.5)	2.46 (1.09–5.55)
Maximum severity
0	177 (49.2)	1
1–2	143 (39.7)	2.75 (1.40–5.40)
2+	40 (11.1)	4.04 (1.60–10.20)
Area of damage m²	357 (0.38^¶)	1.36⁺ (0.91–2.03)
Mould growth
No	327 (90.6)	1
Mould spots	14 (3.9)	4.01 (1.12–14.32)
Visible mould	20 (5.5)	1.95 (0.69–5.47)
Mould odour
No	353 (97.8)	1
Yes	8 (2.2)	2.96 (0.62–14.19)
Damage in child's bedroom^#
No	300 (83.8)	1
Yes	58 (16.2)	1.97 (1.00–3.90)
Area of damage m²	352 (0.04^¶)	1.52⁺ (0.63–3.70)

Data are presented as n (%) or odds ratio (95% confidence interval), unless otherwise stated. ^#: damage in the child's bedroom was recorded separately during the visit. In addition, all observed damage was classified after the visit as occurring in any of the main living areas. ^¶: mean area of damage; ⁺: for a 1 m² change in area of damage.

Table 5—

Moisture-damage characteristics in the main living area and in child's bedroom and their multivariate adjusted association with asthma, stratified by atopy and age (≤30 months or >30 months) of the case

	Nonatopic cases versus their controls		Atopic cases versus their controls		Younger cases versus their controls		Older cases versus their controls
	n	OR (95% CI)	n	OR (95% CI)	n	OR (95% CI)	n	OR (95% CI)
Main living area
Severity of damage
No	77	1	137	1	147	1	104	1
Minor or major	43	2.11 (0.68–6.53)	49	2.84 (1.15–7.05)	62	2.95 (1.22–7.13)	48	2.16 (0.79–5.95)
Visible mould
No	60	1	95	1	112	1	72	1
Yes	57	1.08 (0.32–3.64)	91	4.74 (0.94–24.01)	96	1.96 (0.87–4.38)	79	0.81 (0.34–1.91)
Damage in child's bedroom^#
No	91	1	24	1	173	1	127	1
Yes	26	1.89 (0.57–6.25)	161	2.10 (0.73–6.01)	35	2.47 (0.92–6.69)	23	2.10 (0.64–6.90)

OR: odds ratio; CI: confidence interval. ^#: damage in the child's bedroom was recorded during the visit. In addition, all observed damage was classified after the visit as occuring in any of the main living areas.