Susceptibiility to Asthma Controlled
by Mod ifying the Environment
Stephen Vesper
U.S. EPA/Office of Research and Development (ORD)/National Exposure Research Laboratory (NERL)
BACKGROUND:!
Asthma afflicts about 6 million children in the U.S. resulting in medical cost of about $5 billion per year. Previously, we established that there were 26 molds that were statis-
tically associated with water-damaged homes which we called Group 1 Molds (Vesper et al.2004) and others which were common to all homes, i.e. the 10 Group 2 Molds.
Analysis of these 36 molds makes up the ERMI© or EPA relative moldiness index©. We sought to determine if removing the water damage and molds reduced the asth-
matic child's need for medical interventions.
METHODS:
1. Using EPA patented mold specific quantitative PCR (MSQPCR), mold concentrations were measured in dust samples obtained from water-damaged homes of asthmatics
children in Cleveland, Ohio and results compared to a set of control homes. From this data and the resulting ERMI© values, an odds ratio for expressing asthma symptoms
was established.
2. The water-damaged homes of half of the asthmatic children were remediated, i.e. water problem fixed and damaged materials and mold removed. The health outcomes
were assessed.
Table 1. Comparison of mold populations in cell equivalents
per g dust from asthma and control homes. (GM ratio = GM
of asthmatic home/GM of control home)
Asthma
("'60)
Aspergillus ochraceus
Aspergillus penicillioides •
Aspergillus s
Aspergillus i/ngui^ _
Aspergillus '/:¦ '.w.ofcr
Penicillium corylophilum 2317.31
Penicillium Group 2 2604.C
Scopulariopsis brevicaulis 1179.C
7704.30
16155.37
33532.34
3.773
2.507
0.947
Molds associated with asthma
Table 2. Odds ratios for predicting illness based on
relative moldiness index© (ERMI©).
ivn
True
Negative
False
Positive
False
Negative
True
Positive
No.
No.
wrong
Odds
-9
2
20
59
61
21
5.90
-!
2
2(
59
61
21
5.9(
-7
2
20
59
61
21
5.90
-6
2
20
59
61
21
5.90
-5
¦
19
59
62
2(
9.32
5
17
2
51
63
19
8.53
5
17
i
56
61
21
4.12
-2
6
16
6
5'
6(
22
3.38
6
16
6
5'
6(
22
3.38
9
13
8
52
61
21
4.50
11
11
10
5(
61
21
5.00
?
11
11
II
49
6(
22
4.45
:
12
10
u
46
58
2'
3.91
<
12
10
17
43
55
27
3.0<
12
10
18
42
5'
28
2.80
12
1(
2(
4(
52
3(
2.40
U
8
25
35
49
3:
2.45
15
27
3:
48
3'
2.62
16
35
25
41
41
1.90
k
17
5
38
22
39
4:
1.97
i
18
41
19
37
45
2.09
12
19
:
45
15
3<
48
i:
19
:
46
1'
3:
49
1.92
i'
19
:
48
12
31
51
1.58
15
2(
2
49
11
31
5:
2.2'
16
2(
2
52
8
28
51
1.5'
17
2<
2
5'
26
56
18
21
1
5'
27
55
2.33
19
21
1
56
<
25
57
1.50
2<
21
1
58
23
59
0.72
21
21
1
58
23
59
0.72
Predictive value of the relative moldiness index (ERMI©)
Table 2 shows the odds ratios for each of the ERMI© values. For
example, a RMI of 1 has an odds ratio of 5.0. In this context,the
odds ratio would quantify the relative proportion (relative risk)
for the population of study homes of developing asthma.
Therefore 61 of 82 homes would be correctly assessed, i.e. 50
true positives and 11 true negatives
Benefit: 10-Fold Reduction
in Medical Intervention
i 12
< 10
O
« 8
0
1 6
2
| 4
_c
"to 2
o
£ 0
Non-Remediated
Remediated
Clinically, moderately severe asthmatic children had a significant decrease in symptom score (p <
0.006) and symptom days (p < 0.003) following remediation of their water- damaged homes.
RESULTS:
Some of the Group 1 molds were associated with asthma in these water-damaged homes but none of the Group 2 molds.
Determination of the ERMI© values produces a useful predictive model of asthma exacerbation.
Removing the water damage and mold, produced a a ten-fold reduction in the need for medical intervention.
( SIGNIFICANCE: I
Determination of the ERMI© value in a water damaged home can be used in a cost benefit analysis and removal of water damage and molds can be used to
reduce asthma costs in the US.
L
ACKNOWLEDGEMENTS!
Primary funding for this research was provided by US Department of Housing and Urban Development, Office of Healthy Homes and Lead Hazard Control grant
OHLHH0065-99. This research was partially supported by the Swetland Center for Environmental Health at CWRU and the National Institutes of Health General Clinical
Research Center grant MOIRR00080. This research was also supported by US EPA Cooperative Agreement CR827942-01 -0 and funds from the US EPA's National Center
for Environmental Assessment's "Children at Risk" Program and "Asthma Initiative"
Although this work was reviewed
by EPA and approved for
publication, it may not necessarily reflect
official Agency policy.
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