Donald E. Morisky, Sakae Kaneko, Satoshi Takeuchi, Masatoshi Abe, Hidehisa Saeki, Yuichiro Tsunemi, Yuki Kitami, Naoko Inomata, Daisuke Onozuka, Norito Katoh, Makoto Sugaya, Yoichi Shintani, Miwa Kobayashi, Shinichi Imafuku, Masutaka Furue, Shinya Abe, Koji Masuda, Hiroyuki Murota, Takaaki Hiragun, and Miki Tanioka
Dear Editor, Recent studies have shown that adherence to treatment is an important factor for good therapeutic outcome in various chronic disorders such as hypertension and diabetes.1,2 In dermatology, patient nonadherence to therapy is also very problematic and has been associated with poor therapeutic outcomes in common skin diseases.3–5 Although there is no ‘gold standard’ to measure medication adherence, an eight-item self-reported scale called the Morisky Medication Adherence Scale-8 (MMAS-8) has been developed by Morisky et al.1 MMAS-8 originally targeted oral medication for hypertensive patients, but it is now applied to measure medication adherence in a wide range of disorders such as diabetes and osteoporosis.2,6 However, there are no reports of studies investigating dermatological adherence using this scale. Therefore, this study assessed medication adherence for oral and topical remedies using a translated version of MMAS-8 together with other socioeconomic background factors in 3096 Japanese dermatological patients. This study was conducted among patients registered in a monitoring system established by Macromill Inc. (Tokyo, Japan). The registered individuals (n = 4144) were prescreened in terms of skin diseases and their intention to participate in this study. In total 3096 eligible patients were enrolled, 1327 with atopic dermatitis, 751 with urticaria, 237 with psoriasis and 781 with tinea. Our web-based questionnaire included the following items: age, sex, marital status, annual income, employment status, educational status, smoking habit, alcohol consumption, frequency of hospital visits, main healthcare institution, oral or topical medication, experience of the effectiveness of oral medication, experience of the effectiveness of topical medication, experience of adverse events associated with oral medication, experience of adverse events associated with topical medication, overall satisfaction with treatment, MMAS-8 for oral medication and MMAS-8 for topical medication. The original MMAS-8 was translated into Japanese according to international guidelines.7 Forward translation of the original questionnaire was undertaken by translation from English into Japanese to produce a version that was semantically and conceptually as close as possible to the original questionnaire. Translation was carried out by two qualified independent linguistic translators; both are native speakers of Japanese and proficient in English. Back translation from Japanese into English was then carried out by another translator, who is a native speaker of English and proficient in Japanese. The back translation form was sent to the original author. Inconsistencies were resolved after repeated discussion among the original author, the English translator and the Japanese investigators and a final version was generated. According to the MMAS-8 score (range 0–8), adherence was defined as high (score 8), medium (score 6 to