[The enhanced clinical efficacy by treated years and the sustained efficacy after treatment of sublingual immunotherapy for Japanese cedar pollinosis].

BACKGROUND

Although sublingual immunotherapy (SLIT) is hopeful therapy for seasonal allergic rhinitis by Japanese cedar pollen, there are many issues to study. We studied the adding effects on clinical efficacy by the treated years and sustained efficacy 1 year after a 3-year period of SLIT.

METHODS

Clinical efficacy of SLIT in patients with Japanese cedar pollinosis treated for different years of 1 year (n=7), 2 years (n=18) or 4 years (n=5) were compared in 2009. Patients, who finished SLIT after a 3-year period and did not received SLIT at the fourth year (n=12), was also compared with those who received SLIT at the fourth year (n=5).

RESULTS

By adding treated year, clinical efficacy of sneezing, rhinorrhea and congestion became better, and symptom-medication score (SMS) was significantly better in the fourth year of SLIT. Patients with the fourth year of SLIT showed better SMS compared with those who finished at the third year.

CONCLUSION

Consecutive treatment of SLIT showed better efficacy. Although it was recommended to continue SLIT therapy at least four years, it needed further study because of small number of patients.