The effectiveness and predictors influencing the outcome of onabotulinumtoxinA treatment in chronic migraine: understanding from diverse patient profiles in a single session.

Objective: This real-world study aimed to investigate how onabotulinumtoxinA affects the outcome of migraine, along with accompanying anxiety, depression, and bruxism among a group of patients with chronic migraine (CM) and define predictors of good response.

Methods: Patients diagnosed with CM who received onabotulinumtoxinA were included in this single-center, real-world retrospective cohort study. Monthly headache days (MHDs), monthly migraine days (MMDs), headache intensity (numeric rating scale-NRS) and headache characteristics were evaluated at baseline and 12 weeks post-treatment. Patient-reported outcome measures (PROMs) included Migraine Disability Assessment Scale (MIDAS), Headache Impact Test-6 (HIT-6) scores, 12-item Allodynia Symptom Checklist (ASC-12), Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI). Response to onabotulinumtoxinA (% reduction in MHDs) and treatment-related adverse events (TRAEs) were also evaluated. OnabotulinumA was applied to the masseter muscles in patients complaining of bruxism.

Results: A total of 72 patients (mean ± SD age: 36.3 ± 8.5 years; 91.7% were female) diagnosed with CM were included. OnabotulinumtoxinA revealed significant decrease in median (IQR) MHDs [from 20(15-25) at baseline to 6(4-10),  < 0.001], MMDs [from 9(6-12) to 3(1-6),  < 0.001] and NRS [from 9(8-10) to 7(6-8),  < 0.001], and the MIDAS [from 54(30-81) to 16(7-24),  < 0.001], HIT-6 [from 67(65-69) to 58(54-64),  < 0.001], ASC-12 [from 6(1.5-9) to 2(0-9),  = 0.002], BAI [from 12(6.5-19) to 9(3-17),  < 0.001] and BDI [from 11(6.5-17) to 3(2-7)  < 0.001] scores at 12 weeks post-treatment. Patients complaining of bruxism received onabotulinumtoxinA injections in the first  = 27 (37.5%) and 12. week post-treatment  = 19 (70.4%) periods. Overall, 70.8% of patients responded (≥50% reduction in MHDs), while 29.2% did not (<50% reduction). Both groups showed similar characteristics in demographics, migraine history, baseline PROMs scores, comorbidities, and prior treatments.

Conclusion: OnabotulinumtoxinA is an effective treatment option that rapidly improves migraine outcomes, disability, and impact while also alleviating comorbid depression and/or anxiety. This study's noteworthy finding is that onabotulinumtoxinA is effective in a majority of CM patients, irrespective of their prior treatment history, migraine characteristics, or concurrent comorbidities. Furthermore, we identified no specific predictors for a favorable response to onabotulinumtoxinA. Applying onabotulinumtoxinA to the masseter muscles can relieve discomfort associated with concurrent bruxism; however, it does not impact migraine outcomes.