Relationship between serum IgA level and allergy/asthma

• Published in: The Korean journal of internal medicine Vol. 32; no. 1; pp. 137 - 145
• Main Authors: Kim, Woo-Jin, Choi, Inseon S., Kim, Chang Seong, Lee, Jeong-Hyeon, Kang, Hyeon-Wook
• Format: Journal Article
• Language: English
• Published: Korea (South) The Korean Association of Internal Medicine 01.01.2017; 대한내과학회
• Subjects: Adult; Animals; Asthma - blood; Asthma - diagnosis; Asthma - immunology; Biomarkers - blood; Bronchial Hyperreactivity - blood; Bronchial Hyperreactivity - diagnosis; Bronchial Hyperreactivity - immunology; Bronchial Provocation Tests; Chi-Square Distribution; Female; Humans; Hypersensitivity - blood; Hypersensitivity - diagnosis; Hypersensitivity - immunology; Immunoglobulin A - blood; Intradermal Tests; Linear Models; Logistic Models; Male; Middle Aged; Odds Ratio; Original; Predictive Value of Tests; Pyroglyphidae - immunology; Retrospective Studies; Risk Factors; Severity of Illness Index; 내과학; Sensitization; Hyper-responsiveness; Immunoglobulin A; Asthma
• ISSN: 1226-3303; 2005-6648; 2005-6648
• DOI: 10.3904/kjim.2014.160

Mucosal immunoglobulin A (IgA) may prevent the entrance of allergens. This study examined the relationship between serum IgA levels (within the normal range) and sensitization to house dust mites (HDM) or airway hyper-responsiveness (AHR). The clinical records of 1,136 adult patients with suspected asthma, for whom test data for serum IgA level and methacholine-AHR were available, were reviewed retrospectively. The AHR/allergy indices were compared among patient groups with low (<140 mg/dL, group I), intermediate (140 to 280 mg/dL, group II), or high (≥280 mg/dL, group III) IgA levels in serum. The HDM skin sensitization rate progressively decreased from 30.0% in group I (n = 139) to 26.8% and 18.5% in groups II (n = 684) and III (n = 313), respectively ( = 0.003). Although both the HDM sensitization degree and the IgA level were significantly related to age, the adjusted odds ratio (OR) of association of a high IgA level (≥ 280 mg/dL) with HDM sensitization was significant (0.617; 95% confidence interval [CI], 0.415 to 0.916; = 0.017). Among younger subjects (≤ 45 years of age) with AHR, the prevalence of moderate/severe AHR progressively decreased (70.6%, 52.3%, and 47.1% in groups I, II, and III [n = 34, 149, and 51]), respectively ( = 0.045). The IgA < 140 mg/dL was a significant risk factor for moderate/severe AHR (OR, 2.306; 95% CI, 1.049 to 5.071; = 0.038). Sensitization to HDM and methacholine-AHR were significantly associated with serum IgA levels in suspected asthmatics, even when those levels were normal.