Neural hyperactivity in the amygdala induced by chronic treatment of rats with analgesics may elucidate the mechanisms underlying psychiatric comorbidities associated with medication-overuse headache.

BACKGROUND: Patients with medication-overuse headache suffer not only from chronic headache, but often from psychiatric comorbidities, such as anxiety and depression. The mechanisms underlying these comorbidities are unclear, but the amygdala is likely to be involved in their pathogenesis. To investigate the mechanisms underlying the comorbidities we used elevated plus maze and open field tests to assess anxiety-like behavior in rats chronically treated with analgesics. We measured the electrical properties of neurons in the amygdala, and examined the cortical spreading depression (CSD)-evoked expression of Fos in the trigeminal nucleus caudalis (TNC) and amygdala of rats chronically treated with analgesics. CSD, an analog of aura, evokes Fos expression in the TNC of rodents suggesting trigeminal nociception, considered to be a model of migraine. RESULTS: Increased anxiety-like behavior was seen both in elevated plus maze and open field tests in a model of medication overuse produced in male rats by chronic treatment with aspirin or acetaminophen. The time spent in the open arms of the maze by aspirin- or acetaminophen-treated rats (53 ± 36.1 and 37 ± 29.5 s, respectively) was significantly shorter than that spent by saline-treated vehicle control rats (138 ± 22.6 s, P < 0.001). Chronic treatment with the analgesics increased the excitability of neurons in the central nucleus of the amygdala as indicated by their more negative threshold for action potential generation (-54.6 ± 5.01 mV for aspirin-treated, -55.2 ± 0.97 mV for acetaminophen-treated, and -31.50 ± 5.34 mV for saline-treated rats, P < 0.001). Chronic treatment with analgesics increased the CSD-evoked expression of Fos in the TNC and amygdala [18 ± 10.2 Fos-immunoreactive (IR) neurons per slide in the amygdala of rats treated with aspirin, 11 ± 5.4 IR neurons per slide in rats treated with acetaminophen, and 4 ± 3.7 IR neurons per slide in saline-treated control rats, P < 0.001]. CONCLUSIONS: Chronic treatment with analgesics can increase the excitability of neurons in the amygdala, which could underlie the anxiety seen in patients with medication-overuse headache.

Clinical indications for acupuncture in chronic post-traumatic headache management.

Chronic post-traumatic headache (PTH) is one of the most common complaints after mild traumatic brain injury, yet evidence to date is insufficient to direct conventional treatment of headaches with this etiology. Therefore, the current guidelines recommend a symptomatic approach for the three patterns of PTHs: migraine-like, tension-like, and mixed symptomatology. To improve response rates and minimize the potential for polypharmacy, adverse effects, and risk of dependency, effective nonpharmacologic options should be employed to support faster and safer patient rehabilitation. Current evidence shows that acupuncture is at least as effective as drug therapy for migraine prophylaxis and neurovascular and tension-type headaches. Because of its safety, cost-effectiveness, and long-lasting benefits, adjunctive acupuncture should be offered to patients with chronic PTHs and may be a valuable primary treatment alternative for those with contraindications to pharmacotherapy. Future head-to-head, adequately powered, well-controlled randomized clinical trials are needed to investigate acupuncture efficacy for PTHs.

Medication overuse as a cause of chronic headache in shunted hydrocephalus patients.

PURPOSE: To highlight the group of hydrocephalus patients known to have a long history of shunt revisions and refractory chronic headache. When a shunt in perfect working order has no effect on headache, other causes of headache should be investigated. In this paper, patients with medication overuse headache are identified and the positive effect of medication withdrawal are described. MATERIALS AND METHOD: Patients with hydrocephalus and shunt referred from the neurosurgical department to the Danish Headache Centre were identified. In all cases, over- and underdrainage was ruled out prior to referral. Six patients with medication overuse headache were documented and their charts were reviewed retrospectively with specific attention to: shunt revisions, inpatient and outpatient contacts, headache data and medication use before and after withdrawal of analgesic medication overuse. RESULTS: A marked reduction in shunt revisions and inpatient contacts in five out of six patients was found and a reduction in outpatient contacts in four out of six patients. Furthermore, an improvement in headache intensity was found in three out of six patients and a reduction in duration was found in two out of six patients. CONCLUSION: This study indicates that it is important to identify shunt patients with persistent chronic headache from causes other than shunt malfunction. By reducing their analgesic intake, it is possible to reduce headaches, the number of surgical interventions and hospital contacts. Hopefully this will raise awareness and lead to further research on the subject.

Disorders presenting with headache as the sole symptom.

Headache is one of the commonest medical complaints, and ranks high among the reasons why people consult neurologists and general practitioners. Most headache patients are, however, managed suboptimally; and indeed, many neurologists find outpatient headache management one of the least engaging parts of their job. Headache may present as part of a symptom complex or it may present alone. When it is part of a complex, the total presentation of the patient serves as pointer to any underlying disease. When it is the sole symptom however, identifying the specific cause can be more difficult. Even though the diagnosis and management of most cases of headache probably do not require sophisticated neurological skills or investigations, failure to recognise an underlying disorder or an attitude of total neglect can be fatal. In this paper, we briefly review some of the disorders reported to have presented with headache as the sole symptom with the aim of drawing attention to the need for proper attitude to every headache complaint even when it initially appears to be trivial. Two groups of headache are recognised - primary and secondary. More than 90% of headaches seen in practice are of the primary type, which includes migraine, tension and cluster headaches. Secondary headache results from a wide range of disorders which may be intracranial, extracranial or systemic. Intracranial causes of headache include tumours, haematomas, infections, idiopathic intracranial hypertension and vascular disorders. Some of the more common extracranial and systemic causes are shown in Tables 1 and 2 respectively. Recognition of these conditions requires a standardised diagnostic approach to history and examination, wherein the patient's history alerts the physician while the physical examination provides support for the diagnosis.

Migraña en el siglo XXI / Migraine in the XXI century

La cefalea es una de las causas más frecuentes de consulta en los servicios de urgencia, en la atención primaria y por supuesto en la consulta del neurólogo. Es una patología que afecta a la calidad de vida de las personas que la padecen y es una importante causa de ausentismo laboral. Dado lo transversal de esta patología, es que médicos de todas las especialidades nos vemos en la obligación de satisfacer la demanda de nuestros pacientes por un alivio. Este artículo no pretende hacer una revisión extensa sobre el tema, sino que en particular nos enfocaremos sobre algunos aspectos que han sido objeto debate, tales como "migraña y hormonas", "migraña y accidente cerebrovascular" y sobre aquellos aspectos que han tenido importantes avances en el último tiempo, tales como el conocimiento de la fisiopatología de la migraña, así como también el reconocimiento, diagnóstico y manejo de la cefalea crónica diaria.

Migraine is one of the most important reasons that explain emergency calls, general medicine and neurological office consultations. Migraine affects the patients quality of daily life and is a cause of working absenteeism. Therefore, many physicians may be in volved in the management of these patients and all of them must be updated about this prevalent condition.The aim of this review is not to make a thorough analysis of migraine; we will mainly focus on important issues such as migraine and hormones, migraine and stroke, a, advances in the understandig of migraine pathophysiology Finally, we address the appropriate diagno management of the prevalent chronic daily headache.