Abstract: ObjectiveTo explore the clinical effects of sublingual immunotherapy with Dermatophagoides farinae drops in patients of different age groups with allergic rhinitis(AR). Methods A total of 240 patients with AR admitted to the hospital from March to August 2016 were divided into six groups based on their age(3-6 years old, preschool group; 7-12 years old, school group; 13-20 years old, puberty group; 21-40 years old, adolescent group; 41-60 years old, middle-age group; older than 60 years, old-age group), with 40 patients in each group. The patients were treated with sublingual administration of Dermatophagoides farinae drops. The desensitization therapy of Dermatophagoides farinae drops included two stages: increasing dose and maintenance dose. The desensitization therapy was combined with symptomatic drug treatment based on the patient's condition. Scores of symptoms, drugs, physical signs, and visual analog scale(VAS)were compared between the two groups after 6 months. The effective and incidence rates of adverse events were statistically analyzed in each group. Results After 6 months of treatment, the scores of symptoms(3.20±0.79, 3.58±0.81, 3.92±0.70, 4.25±0.72, 4.59±0.75, and 4.96±0.80 points), drugs(0.84±0.32, 0.98±0.30, 1.14±0.41, 1.33±0.44, 1.52±0.40, and 1.72±0.48 points), physical signs(0.18±0.02, 0.21±0.05, 0.24±0.06, 0.27±0.07, 0.31±0.06, and 0.35±0.07 points), and VAS(1.82±0.39, 2.08±0.51, 2.31±0.50, 2.54±0.53, 2.78±0.52, and 3.00±0.46 points)significantly improved in the preschool, school, puberty, adolescent, middle-age, and old-age groups. The lower the age of the patient, more obvious were effects of score improvement(F=28.111, 28.111, 48.241, 32.607; P<0.001). The effective rates of efficacy in the preschool, school, puberty, adolescent, middle-age, and old-age groups were 95.00%, 95.00%, 90.00%, 87.50%, 87.50%, and 82.50%, respectively(χ2=20.293, P=0.161). The incidence rates of adverse events in the adolescent, middle-age, and old-age groups(30.00%, 25.00%, and 25.00%, respectively)were lower than those in the preschool, school, and puberty groups(7.50%, 5.00%, and 7.50%, respectively)(χ2=6.646, 4.501, 4.501, 8.658, 6.275, 6.275, 6.646, 4.501, 4.501; P=0.010, 0.034, 0.034, 0.003, 0.012, 0.012, 0.010, 0.034, 0.034). Conclusion Sublingual immunotherapy with Dermatophagoides farinae drops is effective in treating patients with AR. The titer lowers with age, while the safety increases.

Key words: Allergic rhinitis, Immunotherapy, Dermatophagoides farinae drops, Age, Treatment outcome