1. PATIENTS' PREFERENCE FOR MIGRAINE PREVENTIVE THERAPY Mario FP Peres; Stephen D Silberstein; Nina F Abraham; Cheryl Gebeline-Myers G038 Background: Understanding the factors influencing patients' preference increases the ability to make rational choices in selecting appropriate acute migraine therapy. However, unlike acute migraine treatment, patients' preferences for migraine preventive treatment have never been studied. Objectives: To evaluate patients' preference for migraine prevention. ethods: We enrolled 250 patients with a primary headache diagnosis (25 men, 100 women) at the Jefferson Headache Center. Age, gender, Body Mass Index (BMI), headache diagnosis, headache frequency, duration, and intensity, as headache severity by the MIDAS score and patients current preventive treatments were ascertained. Patients were asked to rate seven aspects of headache prevention (efficacy, speed of onset, out-of-pocket expenses, side-effects, formulation of therapy, type of treatment, and frequency of dosing) in order of importance (1-7). Each patient also evaluated 12 different clinical scenarios, each one containing a simulation of two hypothetical headache preventive treatments, where patients could choose product A, B or neither. Each product had efficacy data (50,75 or 100% of headache elimination), side effect profile (weight gain, concentration difficulty, and fatigue), and dosing frequency (once every 3 months, once per day, twice per day). Results: Most patients were caucasians. Mean BMI was 26.55 +- 5.34, range (17-45). Mean history of headache was 20.93 years. Fifty patients (40%) had 45 or more headache days in the past 3 months. Mean headache intensity score (0-10 scale) was 5,7 +- 1,8. Patients were on preventive treatments, including 48 (41%) beta-blockers, 19 (16%) calcium-channel blockers, 52 (44%) antidepressants, 46 (39%) anti-epileptics, 16 (14%) had neurotoxins, 28 (24%) vitamins/herbal therapies, and 38 (32%) non-medicinal therapy. From the seven aspects of migraine prevention patients were asked to rate, 90 (72%) rated effectiveness the most important aspect, followed by 15 (12%) who rated speed of onset, 4 (3%) out-of-pocket expenses, 7 (6%) absence of side effects, 4 (3%) formulation of therapy, 3 (2%) type of treatment (prescription/vitamin), none rated frequency of dosing as the most important factor. In the analysis of preventive treatment scenarios patients were more likely to choose treatments with higher efficacy rates, less side effects and less frequent dosing schedule. Patients preferred treatment options with higher efficacy rates even in the presence of side effects and more frequent dosing schedule. Conclusions: Patients' preference for migraine prevention is very important in headache management. Patients rated efficacy the most important aspect in preventive and preferred View this poster at www.cefaleias.com.br IIEP- Albert Einstein, Sao Paulo Headache Center, Sao Paulo, SP, Brazil. Jefferson Headache Center, Philadelphia, PA, USA. Effectiveness 72% Speed of onset 12% Absence of side effects 6% Cost 3% Formulation 3% Tx type 2% Dosing Legend: First bar (100% efficacy with side effect), second bar (75% efficacy without side effect), third bar (neither). WG= weight gain, concx=concentration problems, fat=fatigue. Patients´ preference for migraine preventive therapy according to 100% vs 75% efficacy with or without side effects in the USA and Brazilian population.