[EFFECTIVENESS OF ADD-ON SUBLINGUAL IMMUNOTHERAPY FOR THE TREATMENT OF JAPANESE CEDAR POLLINOSIS-ASSOCIATED ALLERGIC ASTHMA IS IT POSSIBLE TO REDUCE THE DOSE OF INHALED CORTICOSTEROID BY ADDING SUBLINGUAL IMMUNOTHERAPY?]

ABSTRACT

BACKGROUND: This study investigated the effect of adjuvant sublingual immunotherapy (SLIT) on inhaled corticosteroid (ICS) dose in patients with pollinosis-associated asthma. METHODS: We retrospectively evaluated patients with cedar pollinosis-associated asthma who initiated pharmacotherapy with or without adjuvant SLIT therapy from December 2014 to December 2016 and who continued treatment for 3 years. Changes in ICS dose (fluticasone propionate or its equivalent), antihistamine use, leukotriene antagonist use and intranasal corticosteroid (INCS) use over the 3-year period were compared. RESULTS: The study included 36 and 35 patients in the add-on SLIT and standard treatment groups, respectively. At 3 years, the add-on SLIT group showed a significant decline in ICS dose (p = 0.024). Although leukotriene antagonist use and INCS use did not differ between the two groups, the percentage of patients using antihistamines at 3 years was significantly lower in the add-on SLIT group than in the standard treatment group (p = 0.009); one in three patients on adjuvant SLIT therapy was able to discontinue ICS treatment. Patients who discontinued ICS treatment were younger (44.6±13.3 years vs. 55.0±14.1 years, p = 0.042), had a higher FEV1% predicted (109.9±14.4 vs. 94.8±18.6, p = 0.02), and were on a lower treatment step (2.1±0.7 vs. 3.0±0.8, p = 0.002) than those who did not. CONCLUSION: The addition of SLIT to standard pharmacotherapy resulted in a significant reduction in ICS dose at 3 years.