100629 - Asthma outcomes in young adults completed sublingual immunotherapy in adolescence
Background
Allergic asthma (AA) is associated with repeated exacerbations and loss of lung function. Sublingual allergen immunotherapy (SLIT) intended to prevent these outcomes. Study goal was to determine AA clinical course and remission rate in young adults completed SLIT in their adolescence.
Method
We searched database of tertiary out-patient pediatric allergic center for records from 2010-2019 years with two criteria: SLIT with house dust mites (HDM) or birch pollen (BP) natural extracts lasted 3 years or longer and AA established before SLIT start. Patients were clinically evaluated during Sep-Dec 2024: GINA asthma control (0-4 points); number of AA exacerbation; last year maintenance medication type and dose; lung function test with salbutamol (assessed at least 14 days outside acute respiratory infection).
Results
We found 271 patients completed SLIT course in the specified period (176 with BP and 95 with HDM); among them, 84 patients were lost to contact and 73 refused to participate. We have analyzed 114 young adults, mean age 27.3±2.4 years, who completed SLIT with BP (68 patients) or HDM (46 pts) allergens for three (48 pts, 42.1%), four (43pts, 37.7%) or five (23pts, 20.2%) years. Prolonged course (4-5 yrs) was more likely with HDM (40pts, 60.6%). At the evaluation, median time from SLIT completion was 6.3 [5.7; 9.2] years.
All patients had mild (80pts, 70.2%) or moderate AA; there were no cases of disease deterioration and 37 cases (32.5%) of conversion from moderate (in childhood) to mild (at the evaluation point) AA. Mean rate of AA exacerbations per patient per year had significantly decreased: before AIT start 1.16±0.12 events, after treatment 0.26±0.05 (p=0.00001) and conserved low at the evaluation point (5-9 years after SLIT completion) 0.39±0.05 (p=0.001).
Positive BD-test (FEV1 change >12% and >200ml) registered more often in patients with shorter SLIT duration (3 years course in 40 pts, 86.9%, irrespectively of allergen).
Most patients decreased maintenance medication during SLIT and conserved this achievement through years. Montelukast and for/bud as needed therapy regiments were more prevalent in BP treated group and among patients with longer duration of SLIT.
Remission of AA (normal spirometry, no exacerbation last year and no regular treatment) registered in 33 pts (29%), 22 of them were treated with BP (32.4% of all BP-treated group) and 11 – with HDM (23.9%), difference was not significant (p=0.063).
Conclusion
SLIT, performed in childhood or adolescence, significantly decrease exacerbation rate and medication load; it also improves spirometry data. These changes persist even 5-9 years after AIT completion.
