Background
Real clinical setting data about onabotulinumtoxinA treatment on chronic migraine are poor, especially in patients with medication-overuse headache (MOH) and ≥ 65 years old, as well as data on predictors of responsivity. W present results on chronic migraine patients treated at the Padua Headache Centre from April 2014 to March 2015.
Materials and methods
By compiling a headache diary, efficacy parameters (mean reduction of headache days and hours) were evaluated at 90 days after the first cycle. We analyzed also: 30% and 50% response rates and the percent of first-time responders to II cycle; association with headache related symptoms and comorbidities (depression/anxiety disorders, hypertension, sleep disturbances, caffeine intake, BMI >30).
Results
Forty patients were evaluated (35 F, 5 M; mean age, 53±12.8) of which 37/40 (93%) with MOH. At 90 days after the first cycle headache diary documented a significant mean reduction of headache days (56.2 vs 69.2, p < 0.005), of the total hours of headache (455.4 vs 601.6, p <0.005), of the hours of moderate pain (147.8 vs 263.5, p < 0.005) and severe pain (102.5 vs 131.2, p < 0.05), of the consumption of triptans (30.7 vs 46.5, p < 0.001) and associations (15.4 vs 22.7, p <0.05). The 8 patients ≥65 years old did not present a significant reduction of efficacy parameters vs younger patients. 50% and 30% response rate was respectively 22.5% and 38% for at least one efficacy parameter, 15% and 25% for headache days, of 20% and 35% for hours, 12.5 and 23% for both parameters. Percent of “first-time 50% responders” was 15.8% and 10.8% respectively for headache days and hours; percent of “first-time 30% responders” was 26.3% and 15.8%. Cluster analysis showed a higher severe headache share and a lower share of mild headache in responsive patients vs non responsive: 146.7 (26.3%) vs 119.1 (17.6%) severe pain hours, 162.2 (29.1%) vs 287.1 (41.1%) mild pain hours. ANOVA analysis did not show significant association between responsivity and headache symptoms or related comorbidities, except for a lower response trend of depression/anxiety at limit of significance (p = 0.07).
Conclusions
OnabotulinumtoxinA treatment appears useful also in a clinical setting with high presence of MOH. Responsive patients are <65 years old and have a higher frequency of severe headache and a lower share of mild headache. Depression/anxiety disorders are associated also to a lower responsiveness trend at limit of significance.
Written informed consent to publication was obtained from the patient(s).
Conflict of interest
The principal author declares that there is no conflict of interest.