When migraine progresses: Transformed or chronic migraine

Migraine may be conceptualized, not just as an episodic disorder, but as a chronic recurrent and sometimes chronic progressive disorder. Transformed migraine, often referred to as chronic migraine is the result of migraine progression. This article will review the clinical features of transformed migraine, highlighting that its phenotype varies according to stage. Early in the process of transformation, attacks with migraine features are very common. As the disease evolves, most attacks lack the migraine features. The risk factors for migraine progression and the mechanisms for progression will be discussed. This review concludes with the prospects for treating transformed migraine and avoiding migraine progression.