Background: Allergen-specific immunotherapy (AIT) is the only available treatment that can induce specific immune tolerance to allergens. However, the treatment course lasts >3 years, and there is no reliable method to predict treatment response. Therefore, in this study we aimed to establish a method that can predict treatment response to AIT in the second year.
Methods: This prospective study enrolled 119 patients who had undergone 2-years of standard-quality house dust mite subcutaneous immunotherapy. Clinical characteristics, skin-prick test response, and treatment response were evaluated at months 4, 6, 12, and 18. Effective AIT was defined as a 25% reduction in average adjusted symptom score (AAdSS) from baseline at the end of the second year of immunotherapy.
Results: The overall efficacy rate at the end of year 2 of the AIT was 67.4%. Age, sex, asthma, body mass index, smoking history, and aeroallergen categories were not associated with efficacy of AIT. Meanwhile, efficacy data at month 4 (odds ratio [OR], 4.250; p = 0.004), month 6 (OR, 10.476; p < 0.000), month 12 (OR, 18.000; p < 0.000), and month 18 (OR, 9.716; p < 0.000) were associated with month 24 efficacy. The area under the curve for improvement at 4, 6, 12, and 18 months was 0.805, 0.834, 0.837, and 0.854, respectively.
Conclusion: Efficacy of AIT at months 4, 6, 12, and 18 is strongly associated with efficacy at month 24. Efficacy as early as month 4 can predict efficacy at the second year, and this may help to determine the need for long-term treatment. Our findings may be useful for identifying novel treatment strategies for AIT.
Keywords: allergen-specific immunotherapy; efficacy; immune tolerance; polysensitization; treatment response.
© 2019 ARS-AAOA, LLC.