P114
Background: OnabotulinumtoxinA is an effective, tolerable and safepreventive treatment for chronic migraine (CM). Other than a reduc-tion in headache frequency or disability, in CM the withdrawal ofconcomitant preventive medication indicates treatment effectivenessand quality of life improvement.
Objective: To characterize the change in the use of oral preventivemedication after treatment with OnabotulinumtoxinA in patientswith migraine.
Methods: This is a multicentre study. We consecutively included pa-tients with migraine (ICHD-3) that were on preventive treatment withOnabotulinumtoxinA. We retrospectively collected demographic data, diagnosis of migraine, frequency and intensity changes, number ofcycle and OnabotulinumtoxinA dose. In addition, we listed the initialand current preventive treatment (number of drugs and group) andthe number and cycle of medications withdrawn. We performed aunivariate and logistic regression analysis.
Results: We included 542 patients: 87.6% women, mean age 47.6 ±11.7 years. A 89.3% had chronic migraine and 10.8% had high fre-quency episodic migraine. The mean reduction in frequency aftertreatment was 13.4±8.2 headache days/month. At baseline, a 91.3%took other preventives and during treatment with Onabotulinumtox-inA a 58.6% withdrew at least one drug, 25.8% stopped completelyall oral preventive drugs. Factors associated with withdrawal were:being male, having >50% response in frequency and intensity, thenumber of infiltrations and a shorter chronification period until thefirst OnabotulinumtoxinA administration (p <0.05). The multivariateanalysis showed that a better response in intensity (OR:1.8 [1.4-2.2], p<0.001), a greater number of infiltrations (OR:1.1 [1.0-1.2], p<0.001)and a shorter chronification period (OR:0.994 [0.992-0.997], p<0.001)were predictors of withdrawal. The ROC curve, showed that 6 Onabo-tulinumtoxinA cycles was the cut-off point that better predicted oralpreventive medication withdrawal (p <0.001).
Conclusions: Treatment with OnabotulinumtoxinA reduces the use ofother preventive medications for migraine. The highest probability ofwithdrawal occurs after 6 cycles of treatment
