Cerebral Amyloid Angiopathy With a Hypomanic Episode Treated With Valproic Acid.

Cerebral amyloid angiopathy (CAA) is a major cause of spontaneous intracerebral hemorrhage in the elderly. There are no reports of CAA causing mania or hypomanic episodes, and the incidence of mania or hypomanic episodes in patients with vascular dementia is generally considered to be rare. Here, we present a case of CAA with hypomania in which valproic acid (VPA) led to improvement in the symptoms of hypomania. An 80-year-old, right-handed Japanese woman with mild cognitive impairment (MCI) presented with a hypomanic episode. Her brain magnetic resonance imaging showed multiple obsolete infarcts and hemorrhages caused by CAA. We diagnosed her as suffering from a hypomanic episode in MCI associated with CAA and started VPA 400 mg/day for seven weeks. Her hypomanic episode gradually improved on VPA. This case indicates that VPA can be useful in the treatment of hypomanic episodes in MCI associated with CAA.