Hypnic headache secondary to a growth hormone-secreting pituitary tumour

Hypnic headache (HH) is a rare, benign, chronic headache disorder, usually affecting aged people and characterized by a close relation to sleep. It was first described by Raskin in 1988 (1). Diagnostic criteria for HH have been established, and HH is included in the recent International Headache Society (IHS) classification as a primary form of headache (IHS classification 4.5) (2). At the time of writing, > 100 cases have been reported in the literature (for review see (3)). Furthermore, several patients with this disorder have been described in Italy (4–12). The pathophysiology of HH remains unclear (13). In most instances, even extensive neurological and neuroradiological examinations will be normal (14). However, symptomatic HH has been reported in relation to obstructive sleep apnoea syndrome (15), arterial hypertension (3), pontine stroke (16) and posterior fossa meningioma (17). We report a case of HH in an acromegalic patient with an intrasellar pituitary adenoma.