Characteristics of mood disorders in Japanese patients with medication-overuse headache.

OBJECTIVE The importance of psychiatric comorbidity in migraine has long been recognized. There is a growing body of evidence that these psychiatric comorbidities share diverse epidemiological properties, pathophysiological mechanisms, and treatment response. The prevalence of psychiatric comorbidities is high in patients with medication-overuse headache (MOH). METHODS To understand the characteristics of mood disorders in MOH in Japanese patients, we studied and evaluated the characteristics of psychiatric comorbidities in MOH. RESULTS The results suggested that mood disorders in MOH are similar to those in endogenous depression but different from those of secondary mood disorders associated with other diseases. Suspicion of depression and intervention are essential for providing medical care for patients with MOH. CONCLUSION Affective disorders diagnosed in migraine patients might later progress to MOH. In contrast, migraine patients without MOH and healthy subjects had a similar prevalence of mood disorders.