Objective: To analyze the prevalence and demography of chronic daily headache (CDH) with analgesic overuse. Methods: A population of 9,984 inhabitants aged 14 or older living in Santoña, Spain, was studied. The authors personally interviewed 4,855 subjects, using a quota sampling approach. Those with headache for ≥10 days/month and some analgesic use were asked to fill in a diary over the course of 1 month. Then, subjects were classified into CDH with or without analgesic overuse subtypes. Quality of life (Short Form-36 Health Survey [SF-36]) was also assessed in this second interview. Results: Headache for ≥10 days/month with analgesic consumption was reported by 332 subjects. Seven had secondary headache. Seventy-four (standardized prevalence 1.41%, 95% CI 1.1 to 1.8) fulfilled criteria for CDH with analgesic overuse. Prevalence in women (2.6%, 2.0 to 3.3) was much higher than in men (0.19%, 0.006 to 0.52). Mean age was 56 years (range 19 to 82 years). As recalled by the subjects, the mean age at onset of CDH was 38 years (range 9 to 82 years), whereas the mean age at onset of CDH with frequent analgesic consumption was 45 years (range 19 to 80 years) and that of primary headache was 22 years (range 5 to 60 years). CDH subjects showed a significant decrease in each SF-36 health-related score as compared with healthy control subjects. Transformed migraine was diagnosed in 49 (prevalence 0.9%), chronic tension-type headache in 20 (0.4%), and new daily persistent headache in 5 (0.1%). Thirty-five percent of patients overused simple analgesics, 22% ergotics, 12.5% opioids, and 2.7% triptans; the remaining 27.8% were overusing different combinations. Conclusion: CDH with analgesic overuse is a common disorder in the general population, mainly in women in their fifties, in whom 5% meet its diagnostic criteria.

Background: Onabotulinumtoxin type A (onabotA) has shown efficacy in chronic migraine (CM). Its precise mechanism of action, however, is unknown.Objective: To analyze a potential relationship between calcitonin gene‐related peptide (CGRP) and vasoactive intestinal peptide (VIP) levels and response to onabotA in CM.Methods: Adult patients with CM were recruited. Matched healthy subjects with no headache history served as controls. CGRP and VIP levels were determined in samples obtained from the right antecubital vein by ELISA outside of a migraine attack and having taken no symptomatic medication prior to treatment with onabotA. OnabotA was administered according to the PREEMPT protocol every 12 weeks for at least two treatment cycles. A patient was considered as a moderate responder when both: (1) moderate‐severe headache episodes were reduced by between 33 and 66%; (2) subjective benefit in a visual scale of 0‐100 was recorded by the patient of between 33‐66%. Patients were considered as excellent responders when both items improved >66%. Those without improvement of at least one‐third in the two items were considered as nonresponders.Results: We assessed plasma samples from 81 patients with CM and 33 healthy controls. CGRP and VIP levels were significantly increased in CM population vs controls. CGRP and, to a lesser degree, VIP levels were significantly increased in responders vs nonresponders. For CGRP, a threshold of 72 pg/mL positively correlated with 95% of nonresponders. The probability of being a responder to onabotA was 28 times higher in patients with a CGRP level above the threshold of 72 pg/mL. Even though the sensitivity for the calculated threshold for VIP was poor, the probability that CM patients with low CGRP levels will respond to onabotA was significantly higher in those patients with high VIP levels.Conclusions: Interictal CGRP and, to a lesser degree, VIP levels measured in peripheral blood are of great help in predicting response to onabotA.

The diagnosis of primary headache disorders is clinical and based on the diagnostic criteria of the International Headache Society (ICHD-3-beta). However several brain conditions may mimic primary headache disorders and laboratory investigation may be needed. This necessity occurs when the treating physician doubts for the primary origin of headache. Features that represent a warning for a possible underlying disorder causing the headache are new onset headache, change in previously stable headache pattern, headache that abruptly reaches the peak level, headache that changes with posture, headache awakening the patient, or precipitated by physical activity or Valsalva manoeuvre, first onset of headache ≥50 years of age, neurological symptoms or signs, trauma, fever, seizures, history of malignancy, history of HIV or active infections, and prior history of stroke or intracranial bleeding. All national headache societies and the European Headache Alliance invited to review and comment the consensus before the final draft. The consensus recommends brain MRI for the case of migraine with aura that persists on one side or in brainstem aura. Persistent aura without infarction and migrainous infarction require brain MRI, MRA and MRV. Brain MRI with detailed study of the pituitary area and cavernous sinus, is recommended for all TACs. For primary cough headache, exercise headache, headache associated with sexual activity, thunderclap headache and hypnic headache apart from brain MRI additional tests may be required. Because there is little and no good evidence the committee constructed a consensus based on the opinion of experts, and should be treated as imperfect.

Background: OnabotulinumtoxinA (onabotA) has shown its efficacy over placebo in chronic migraine (CM), but clinical trials lasted only up to one year.Objective: The objective of this article is to analyse our experience with onabotA treatment of CM, paying special attention to what happens after one year.Patients and methods: We reviewed the charts of patients with CM on onabotA. Patients were injected quarterly during the first year but the fifth appointment was delayed to the fourth month to explore the need for further injections.Results: We treated 132 CM patients (mean age 47 years; 119 women). A total of 108 (81.8%) showed response during the first year. Adverse events, always transient and mild-moderate, were seen in 19 (14.4%) patients during the first year; two showed frontotemporal muscle atrophy after being treated for more than five years. The mean number of treatments was 7.7 (limits 2–29). Among those 108 patients with treatment longer than one year, 49 (45.4%) worsened prior to the next treatment, which obliged us to return to quarterly injections and injections were stopped in 14: in 10 (9.3%) due to a lack of response and in four due to the disappearance of attacks. In responders, after an average of two years of treatment, consumption of any acute medication was reduced by 53% (62.5% in triptan overusers) and emergency visits decreased 61%.Conclusions: Our results confirm the long-term response to onabotA in three-quarters of CM patients. After one year, lack of response occurs in about one out of 10 patients and injections can be delayed, but not stopped, to four months in around 40% of patients. Except for local muscle atrophy in two cases treated more than five years, adverse events are comparable to those already described in short-term clinical trials.