The journal of headache and pain
-
Review
Provoked versus spontaneous migraine attacks: pathophysiological similarities and differences.
The onset and duration of spontaneous migraine attacks are most often difficult to predict which, in turn, makes it challenging to study the neurobiologic underpinnings of the disease in a controlled experimental setting. To address this challenge, human provocation studies can be used to identify signaling molecules (e.g. calcitonin gene-related peptide, pituitary adenylate cyclase-activating polypeptide) that, upon intravenous or oral administration, induce migraine attacks in people with migraine and mild or no headache in healthy volunteers. This approach has proven to be valid for decades and plays an integral role in mapping signaling pathways underlying migraine pathogenesis and identification of novel drug targets. However, the question arises as to whether the pathogenic mechanisms of provoked and spontaneous migraine attacks differ. In this paper, we provide an opinionated discussion on the similarities and differences between provoked and spontaneous attacks based on the current understanding of migraine pathogenesis. ⋯ People with migraine describe that provoked attacks resemble their spontaneous attacks and can be treated with their usual rescue medication. From a neurobiologic standpoint, provoked and spontaneous migraine attacks appear to be similar, except for the source of migraine-inducing substances (exogenous vs. endogenous source). In addition, provoked attacks can likely not be used to study the events that precede the release of migraine-inducing signaling molecules from sensory afferents and/or parasympathetic efferents during spontaneous attacks.
-
Calcitonin gene-related peptide (CGRP) inhibitors have been developed as options for treatment of chronic and episodic migraine. We present our experience of the use of erenumab in a tertiary headache centre. ⋯ Erenumab was an effective treatment for chronic migraine in this treatment resistant population over 3 months of follow up. Presence of daily headache predicted poorer response but there was still a significant positive response rate in this group.
-
Headache attributed to intracranial endovascular procedures is described in the ICHD-3. Our aim was to study the frequency and characteristics of headache specifically related to thrombectomy in patients with ischemic stroke. ⋯ Almost one-third of patients with ischemic stroke who undergo endovascular thrombectomy experience headache in the first 24 hours, occurring more frequently in patients who had a previous history of headaches regardless of the procedure complexity.
-
Large numbers of people with headache who would benefit are not reached by headache services. Among the causes are poor or disorganized provision of headache services, but reluctance to seek healthcare has frequently been identified as a significant barrier. We conducted a national survey of people with headache to assess the extent of this problem in Denmark, a country with well organized, highly resourced, and readily accessible services. ⋯ Headache disorders continue to be a problem, even in a high-income country with free and easily accessible headache services. Further studies are needed to investigate and clarify why even people with the highest burden are hesitant to seek and make use of widely available headache services.
-
The pathogenesis of migraine chronification remains unclear. Functional and structural magnetic resonance imaging studies have shown impaired functional and structural alterations in the brains of patients with chronic migraine. The cerebellum and periaqueductal gray (PAG) play pivotal roles in the neural circuits of pain conduction and analgesia in migraine. However, few neurotransmitter metabolism studies of these migraine-associated regions have been performed. To explore the pathogenesis of migraine chronification, we measured gamma-aminobutyric acid (GABA) and glutamate/glutamine (Glx) levels in the dentate nucleus (DN) and PAG of patients with episodic and chronic migraine and healthy subjects. ⋯ Neurochemical levels in the DN and PAG may provide evidence of the pathological mechanisms of migraine chronification. Correlations between migraine characteristics and neurochemical levels revealed the pathological mechanisms of the relevant characteristics.