High rates of secondary non-adherence causes decreased efficacy of 0.1% topical tacrolimus in adult eczema patients: results from a multicenter clinical trial

Abstract

Background: Patients tend to apply topical medications less frequently, in improper amounts. Not only frequency but also application amount may influence treatment outcome. However, studies on relationship between application amount and objective treatment outcome have rarely been conducted.Objective: To assess efficacy of topical agent according to application amount in adult patients, using the finger-tip unit method.Methods: The efficacy of 0.1% topical tacrolimus in adult patients with localised atopic dermatitis was assessed using EASI, TIS, IGA, and PGA scores at baseline, follow-up. Adherence in amount was evaluated after 2 weeks of treatment using the ratio of the actual amount applied to the expected amount applied (A/E).Results: Twenty-seven patients (20.93%) used topical tacrolimus in proper amounts (A/E: 0.8–1.2). However, 86 patients (66.67%) underused topical tacrolimus; 16 (12.40%) patients overused topical tacrolimus. Decreases in EASI scores between baseline and 2 weeks of follow-up in each group (under-amount, proper amount, over-amount) were 1.64, 4.65 and 4.21, respectively. Treatment efficacy increased in accordance with application amount. Further, TIS, IGA, PGA, VAS for Itch and DLQI scores improved concomitantly, exhibiting similar tendencies.Conclusion: Application amount of topical agent is important in increasing treatment efficacy in adult patients with atopic dermatitis.