Review: Delusions in Dementia

Introduction The definition of a delusion is 'a false, unshakeable idea or belief . . . held with extraordinary conviction and subjective certainty' [1]. Delusions are a common symptom of a range of psychiatric illnesses including schizophrenia, depression, bipolar disorder and dementia. The inclusion of dementia in this list is sometimes surprising to both doctors and carers, who restrict the symptoms of dementia to the cognitive domain; yet Alzheimer's first description was of a 51year-old woman with focal cognitive deficits, delusions of jealousy and auditory hallucinations [2]. Considerable research has focused on the neuropathological findings, neuropsychological deficits and genetics of these diseases. It is only more recently that we have begun to untangle the non-cognitive or psychiatric features of the dementias.