Botulinum toxin A (BTA) is widely used as treatment of chronic migraine. Efficacy in studies, however, was only modest and likely influenced by unblinding due to BTA-induced removal of forehead... Show moreBotulinum toxin A (BTA) is widely used as treatment of chronic migraine. Efficacy in studies, however, was only modest and likely influenced by unblinding due to BTA-induced removal of forehead wrinkles. Moreover, most study participants were overusing acute headache medications and might have benefitted from withdrawal. We assessed in a double blind, placebo-controlled, randomized clinical trial whether add-on therapy with BTA enhances efficacy of acute withdrawal. Participants were enrolled between December 2012 and February 2015, with follow-up to January 2016, in a single academic hospital in the Netherlands. A total of 179 participants, male and female, aged 18-65, diagnosed with chronic migraine and overuse of acute headache medication were included. All participants were instructed to withdraw acutely from all medication for a 12-week period, in an outpatient setting. In addition, they were randomly assigned (1:1) to 31 injections with BTA (155 units) or placebo (saline); to prevent unblinding, placebo-treated participants received low doses of BTA (17.5 units in total) in the forehead, along with saline injections outside the forehead region. Primary endpoint was percentage change in monthly headache days from baseline to the last 4 weeks of double-blind treatment (Weeks 9-12). Among 179 randomized patients, 90 received BTA and 89 received placebo, and 175 (98%) completed the double-blind phase. All 179 patients were included in the intention-to-treat analyses. BTA did not reduce monthly headache days versus placebo (-26.9% versus -20.5%; difference -6.4%; 95% confidence interval: -15.2 to 2.4; P = 0.15). Absolute changes in migraine days at 12 weeks for BTA versus placebo were -6.2 versus -7.0 (difference: 0.8; 95% confidence interval: -1.0 to 2.7; P = 0.38). Other secondary endpoints, including measures for disability and quality of life, did also not differ. Withdrawal was well tolerated and blinding was successful. Thus, in patients with chronic migraine and medication overuse, BTA does not afford any additional benefit over acute withdrawal alone. Acute withdrawal should be tried first before initiating more expensive treatment with BTA. Show less
Cutaneous allodynia is a common feature accompanying migraine attacks and considered a clinical marker for central sensitization. In a longitudinal study, we wanted to investigate if allodynia in... Show moreCutaneous allodynia is a common feature accompanying migraine attacks and considered a clinical marker for central sensitization. In a longitudinal study, we wanted to investigate if allodynia in migraine patients is a predictor of increasing frequency of migraine days. We included 3029 well-defined, web-based migraine patients (86% female, mean age 42.8 ± 11.4 years, 61% migraine without aura). Questionnaires on migraine characteristics (including allodynia), depression and demographic factors were applied. The number of migraine days was measured twice. Multivariate regression models were used, with correction for other factors that are involved in the relation between allodynia and the number of migraine attacks or migraine days, with specific focus on depression. Of all 2331 eligible migraine patients, 1624 (70%) had allodynia. Lifetime depression was an independent risk factor for allodynia (odds ratio 1.52, 95% confidence interval 1.26-1.84), as well as female gender, low age at onset, and high migraine attack frequency. Analysis of the longitudinal data (in migraineurs with a follow-up period of >6 months) showed that, apart from the known risk factors (low age at onset, high baseline number of migraine days, and depression), allodynia was an independent predictor for increase in number of migraine days over a mean follow-up period of 93 ± 30 weeks (median 103 weeks, range 26-160 weeks). Cutaneous allodynia is a risk factor for migraine chronification and may warrant preventive treatment strategies. Show less