Conversion pseudodementia in an elderly subject

Background

Few cases of conversion pseudodementia in older people have been reported. The term is used to describe a syndrome of cognitive impairment, regression and physical dependency without evidence for an organic dementia. Conversion pseudodementia raises important diagnostic and therapeutic issues.

Materials and methods

We present a case of a 73-year old male with symptomatology compatible with conversion pseudodementia. Differential diagnosis and therapeutic interventions are discussed.

Results

The patient was admitted to our hospital presenting cognitive decline of a rapid onset and progress in 20 days time. Agitation and bursts of anger against his wife characterized his behavior. During the past six years he had been receiving antidepressant medication. Recent CT scan of the brain was normal and the score in MMSE (Mini Mental State Examination), six months ago was 27/30. During his hospitalization no apparent depressive symptoms were detected, but the performance of MMSE revealed a score of 0/30 and poor cooperation. The patient received mirtazapine, at a dose of 60 mg/day. He kept being aggressive towards his wife, on whom he was dependent and sometimes he was wandering in the hospital, being unable to find his way to the ward. The information about his premorbid personality suggested a stubborn person characterized by perfectionistic traits and somatising behavior. The rapid onset of the symptoms of dementia and the clinical observation of this patient suggested the diagnosis of conversion pseudodementia. He was discharged after 35 days. No improvement of his mental state was observed.

Discussion

The incidence of conversion pseudodementia is not known. It is possible that many cases go unrecognized and get a diagnosis of pseudodementia due to depression. This entity has also been reported in younger patients. When present in older subjects it requires careful assessment and may be diagnosed only in the absence of organic dementia or depression. In some cases the diagnosis is confirmed only by long-term follow up.