Risk Factors affecting the therapeutic effect of onabotulinumtoxin A on chronic migraine: A retrospective study

Abstract

Background OnabotulinumtoxinA demonstrates effectiveness in chronic migraine prevention but is hindered by variable patient responses. Our study aims to identify both modifiable and non-modifiable risk factors influencing onabotulinumtoxinA response. Methods Retrospective cohort study at a tertiary hospital, focusing on chronic migraine patients treated with onabotulinumtoxinA. Data on modifiable, non-modifiable risk factors and patient perceptions were collected through medical records and questionnaire. Results 131 patients underwent the procedure, with a median age of 45 years; 94% were female. Twelve-month follow-up data revealed a statistically significant decrease in migraine episodes. Before onabotulinumtoxinA applications, the mean episodes frequency was 26; at 3-month it was 13; at 6-month follow-up it was 12; at 9-month follow-up it was 11 and at 12-month follow-up it was 10. A third of patients stopped overusing medication after treatment. Univariate logistic regressions for response to onabotulinumtoxinA show that fibromyalgia was associated with a lower likelihood of response to onabotulinumtoxinA ≥ 50% (OR=0.213, p=0.031), while secondary education was associated with a higher likelihood of response (OR=4.400, p=0.029). Adjusted logistic regression shows that patients with fibromyalgia were less likely to have a ≥ 50% response to onabotulinumtoxinA (aOR=0.064, p=0.033). Conclusions In conclusion, our study confirms the effectiveness of onabotulinumtoxinA in reducing migraine frequency in real-life. Additionally, our findings suggest that individuals with fibromyalgia may be less likely to positively respond to onabotulinumtoxinA.