Table 1 Description of study participants by cluster, NHANES 2005–2006
From: Endotoxin clustering with allergens in house dust and asthma outcomes in a U.S. national study
Participants and home characteristics | Cluster 1 | Cluster 2 | Cluster 3 | P-value | All participants |
|---|---|---|---|---|---|
Prevalence, % | 17.8 | 48.9 | 33.3 | 100 | |
Age groups, % | < 0.001 | ||||
< 6 year | 5.9 | 6.1 | 8.9 | 7.0 | |
6–17 year | 9.6 | 19.9 | 17.5 | 17.3 | |
≥ 18 year | 84.6 | 73.9 | 73.5 | 75.7 | |
Gender, % | 0.25 | ||||
Male | 48.7 | 48.0 | 50.3 | 48.9 | |
Female | 51.3 | 52.0 | 49.7 | 51.1 | |
Race/ethnicity, % | < 0.001 | ||||
Non-Hispanic Whites | 58.1 | 80.4 | 55.3 | 68.1 | |
Non-Hispanic Blacks | 23.8 | 4.1 | 18.3 | 12.3 | |
Mexican-Americans | 9.5 | 6.3 | 14.0 | 9.4 | |
Other | 8.6 | 9.2 | 12.4 | 10.1 | |
PIR, % | < 0.001 | ||||
< 1.85 | 32.5 | 23.9 | 46.3 | 32.8 | |
≥ 1.85 | 67.5 | 76.1 | 53.7 | 67.2 | |
Smoker in home, % | 17.8 | 21.2 | 19.4 | 0.45 | 20.0 |
Mildew or musty smell, % | 14.5 | 14.3 | 21.0 | 0.006 | 16.6 |
Cockroaches in home, % | 12.4 | 9.5 | 23.8 | < 0.001 | 14.8 |
Dog in home, % | 15.5 | 76.7 | 29.8 | < 0.001 | 48.0 |
Cat in home, % | 9.9 | 69.1 | 14.1 | < 0.001 | 36.9 |
Floor covering, % | 0.38 | ||||
Carpeted floor | 84.5 | 87.4 | 88.8 | 87.3 | |
Smooth surface | 11.6 | 9.0 | 7.9 | 9.1 | |
Combination carpet and smooth surface | 3.9 | 3.6 | 3.3 | 3.6 | |
When was home built, % | < 0.001 | ||||
Before 1978 | 41.0 | 44.2 | 57.8 | 47.8 | |
After 1978 | 59.0 | 55.8 | 42.2 | 52.2 | |
Type of home, % | < 0.001 | ||||
Trailer | 4.8 | 6.3 | 10.4 | 7.4 | |
Detached family house | 59.8 | 73.0 | 63.0 | 67.3 | |
Attached family house | 11.0 | 8.3 | 9.0 | 9.0 | |
Apartment | 24.4 | 12.3 | 17.6 | 16.2 | |
Respiratory outcomes, % | |||||
Current asthma | 7.2 | 10.0 | 7.8 | 0.01 | 8.8 |
Wheezing in past 12 months | 13.6 | 18.3 | 14.3 | < 0.001 | 16.2 |