Risk factors affecting the therapeutic effect of onabotulinum toxin a on chronic migraine.

BACKGROUND

OnabotulinumtoxinA demonstrates effectiveness in chronic migraine prevention but is hindered by variable patient responses. This study aims to identify modifiable and non-modifiable risk factors influencing the response to onabotulinumtoxinA.

METHODS

We conducted a retrospective cohort study at a tertiary hospital involving chronic migraine patients treated with onabotulinumtoxinA. Data on risk factors and patient perceptions were collected through medical records and questionnaires.

RESULTS

A total of 131 patients were included. At 12 months, a significant reduction in headache frequency was observed: from 26 episodes pre-treatment to 13 at 3 months, 12 at 6 months, 11 at 9 months, and 10 at 12 months. A third of patients stopped overusing medication after treatment. Univariate logistic regressions revealed that fibromyalgia was associated with a reduced likelihood of achieving ≥50% response to onabotulinumtoxinA (OR (odds ratio) = 0.213,  = 0.031), while secondary education was associated with an increased likelihood of response (OR = 4.400,  = 0.029). Adjusted logistic regression confirmed that fibromyalgia significantly reduced the likelihood of ≥50% response (aOR (adjusted odds ratio) = 0.064,  = 0.033).

CONCLUSIONS

This study confirms the real-world effectiveness of onabotulinumtoxinA in reducing headache frequency. Furthermore, patients with fibromyalgia may have a diminished likelihood of responding positively, underscoring the importance of personalized treatment strategies.