Association between temporary housing habitation after the 2011 Japan
earthquake and mite allergen sensitization and asthma development.
Abstract
Background: We previously reported increased prevalence of asthma in
adults who lived in temporary housing after the 2011 Great East Japan
Earthquake. To investigate changes in asthma prevalence and
mite-specific immunoglobulin E (IgE) titers in temporary housing
residents from 2014 through 2019. Methods: We diagnosed asthma in
Ishinomaki city temporary housing residents (age, 15 years) by using
the GINA guidelines. We analyzed serum antigen-specific IgE levels to
Dermatophagoides farinae (Der f), Dermatophagoides pteronyssinus (Der
p), and Aspergillus fumigatus. Results: The prevalence of asthma
exceeded 20% across all age groups throughout the study period. The
proportion of study participants with a ‘positive’ antigen-specific IgE
titer (i.e., 0.35 IUA/mL) was higher in asthmatics than in
non-asthmatics for Der f and Der p but not for Aspergillus fumigatus.
Residents 50 years old who diagnosed asthma or non-asthma, the
percentage with Der f -specific IgE titer 0.10 IUA/mL was higher than
in those with 0.35 IUA/mL. Among study participants, asthma onset
occurred before the earthquake, during residence in shelters or
temporary housing, and, after 2016, moving out of temporary housing. The
Der p-specific IgE level was positively correlated with the duration of
temporary housing (P < 0.05, r = 0.41) and inversely
correlated with the time elapsed since moving out of temporary housing
(P < 0.05, r = –0.35). Conclusions: Mite allergen
sensitization was found in non-asthmatic temporary housing residents
after the 2011 Japan earthquake and tsunami; asthma developed even after
subjects moved out of temporary housing.