RESUMEN
BACKGROUND: Sublingual immunotherapy (SLIT) is safe and effective but compliance is problematic. In this study we evaluated dropout and compliance among adults (≥20 years of age) and adolescents (<20 years of age) for Japanese cedar pollen extract (JCPE), an aqueous SLIT approved in 2014 in Japan. METHODS: Administrative claims data on 1236 Japanese patients, 846 adults (mean age, 43.0 years; 41.8% female) and 249 adolescents (mean age, 14.1 years; 36.6% female), with a JCPE prescription between October 2014 and June 2016 were reviewed. Adults and adolescents were divided according to the year they started SLIT (1- and 2-year cohorts) to calculate dropout and compliance and identify associated factors using multivariate Cox and linear regression models. RESULTS: In 1- and 2-year adult cohorts, dropout rates were 13.5% and 22.1% and compliance rates were 92.8% and 88.8%, respectively. Adolescents had higher dropout and lower compliance. Patients 40-59 years of age had a lower dropout risk than patients 20-29 years of age. Dropout hazard ratios (95% confidence interval) in 1- and 2-year cohorts were 0.26 (0.12-0.58) and 0.40 (0.17-0.93) in patients 40-49 years of age and 0.32 (0.14-0.75) and 0.35 (0.13-0.92) in patients 50-59 years of age, respectively. Younger age contributed to lower compliance in 1- and 2-year adult cohorts (p = 0.001 and p = 0.02, respectively). Systemic steroidal medication history and male gender were positively associated with compliance in adults but not in adolescents. CONCLUSION: High dropout rate was associated with younger generations. Compliance in adults, but not in adolescents, was associated with age, systemic steroidal medication history, and gender.