Page 127 - The clinical aspects and management of chronic migraine Judith Anne Pijpers

Summary and General discussion
Thesis derived perspectives on clinical aspects and management of chronic migraine
This thesis explores various clinical aspects of chronic migraine. Due to the complexity of the underlying processes involved in migraine chronification, this form of migraine is challenging to prevent and treat. This thesis pays attention to modifiable risk factors for chronic migraine, and treatment of chronic migraine by means of withdrawal therapy, Botulinum toxin A and behavioural intervention.
Chapter 1 first describes epidemiology and criteria of (chronic) migraine, and current knowledge on its pathophysiology. Three main component in the pathophysiology are stressed: i) the activation of the trigeminal vascular system (either initiated by cortical events or central generators), causing intracranial hypersensitivity and experience of headache; ii) enhanced pain facilitation of the ascending pain pathway by central sensitisation: hypersensitivity of the trigeminal nuclei in the brainstem and the thalamus, clinically causing cephalic and extracephalic allodynia; and iii) lack of pain inhibition by alterations in the descending pain modulating pathways (See chapter 1, figure 1 and 2). Major risk factors for chronic migraine are medication overuse, psychiatric comorbidity such as depression, and the presence of allodynia. Chronic migraine is a highly disabling and difficult to treat disorder. Since the majority of patients also overuse acute headache medication, the first step in treatment is medication withdrawal. In the Netherlands, withdrawal therapy comprises abrupt cessation of all acute headache medication and caffeine for 12 weeks in an outpatient setting. Since the registration trials in chronic migraine, treatment with botulinum toxin A (before withdrawal of overuse medication) has been a matter of debate.
Chapter 2 elaborates on the psychiatric risk factors for chronic migraine. Symptom dimensions of affective disorders of migraine patients were compared to patients with current and past psychopathology and healthy controls. Migraine patients differ from healthy controls on all three dimensions of affective disorders, with a lack of positive affect (depression specific), a higher negative affect (non-specific) and higher somatic arousal (anxiety specific). The difference is most striking for somatic arousal, for which the scoring is comparable to
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Summary and general discussion
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