IgE sensitization to inhalant allergens and the risk of airway infection and disease: A population-based study.
BACKGROUND
Immunoglobulin E (IgE) sensitization, which is the propensity to develop IgE antibodies against common environmental allergens, is associated with a lymphocyte T-helper type 2 (Th2) skewed immune response and a high risk of allergic respiratory disease. Little is known about whether IgE sensitization confers an increased risk of respiratory infections in adults. We investigated the association between IgE sensitization and the incidence of acute airway infections, other infections and chronic lower airway disease events as recorded in nation-wide registries.


METHODS
We included 14,849 persons from five population-based studies with measurements of serum specific IgE positivity against inhalant allergens. Participants were followed by linkage to Danish national registries (median follow-up time 11.3 years). The study-specific relative risks were estimated by Cox regression analysis, meta-analysed, and expressed as hazard ratios, HRs (95% confidence intervals, CIs).


RESULTS
The relative risks for IgE sensitized vs. non-sensitized were: for pneumonia (HR = 1.20, 95% CI: 1.01, 1.41), other acute airway infection (HR = 0.86, 95% CI: 0.60, 1.22), infection (HR = 1.06, 95% CI: 0.90, 1.24), asthma (HR = 2.26, 95% CI: 1.79, 2.86), and other chronic lower airway disease (HR = 1.31, 95% CI: 1.08, 1.58). In never smokers, the higher risk of pneumonia (HR = 1.73, 95% CI: 1.23, 2.44) and asthma (HR = 3.17, 95% CI: 2.10, 4.76) among IgE sensitized was more pronounced.


CONCLUSIONS
IgE sensitization was associated with a higher risk of asthma, other chronic lower airway diseases, and pneumonia. However, the association between IgE sensitization and pneumonia may be explained by undiagnosed asthma causing the pneumonia. Further studies are needed for confirmation.
Research Centre for Prevention and Health, Capital region of Denmark, Glostrup, Denmark.
Tea
http://orcid.org/0000-0003-0031-5726
T
Skaaby
Research Centre for Prevention and Health, Capital region of Denmark, Glostrup, Denmark.
Lise Lotte Nystrup
LL
Husemoen
Research Centre for Prevention and Health, Capital region of Denmark, Glostrup, Denmark.
Betina Heinsbæk
BH
Thuesen
Research Centre for Prevention and Health, Capital region of Denmark, Glostrup, Denmark.
Runa Vavia
RV
Fenger
Research Centre for Prevention and Health, Capital region of Denmark, Glostrup, Denmark.|Department of Clinical Experimental Research, Glostrup University Hospital, Glostrup, Denmark.|Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
Allan
A
Linneberg
D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003718:Denmark; D005260:Female; D006801:Humans; D007114:Immunization / Q000009:adverse effects / Q000706:statistics & numerical data*; D007073:Immunoglobulin E / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012130:Respiratory Hypersensitivity / Q000453:epidemiology*; D012141:Respiratory Tract Infections / Q000453:epidemiology*
D007073:Immunoglobulin E