Dementia with Lewy bodies.

OBJECTIVE: The aim of this paper is to summarise recent clinical and research findings with regard to dementia with Lewy bodies (DLB).
METHOD: A literature review (Medline) was carried out, as well as a review of reports of recent DLB symposia of international meetings and of other relevant papers and data known to the authors.
RESULTS: Dementia with Lewy bodies, as the disorder should be known, is the second commonest form of degenerative dementia, accounting for up to 20% cases in the elderly. It is characterised by fluctuating cognitive impairment, spontaneous parkinsonism and recurrent visual hallucinations. Consensus clinical and neuropathological criteria have been published. The clinical criteria have been shown to have high specificity, but may still lack sensitivity. Recognition of DLB is clinically important in view of the high incidence (60%) of adverse and life-threatening reaction to antipsychotics, the difference in prognosis and, possibly, the differential treatment response to cholinergic therapy. Neuroimaging changes have not been well described in DLB but some show promise as potential markers to differentiate DLB from AD. These include relative preservation of temporal lobe structures on magnetic resonance imaging and loss of pre- and postsynaptic dopaminergic markers on single photon emission tomography.
CONCLUSIONS: Dementia with Lewy bodies is a common cause of cognitive impairment in late life which appears to be clinically and neuropathologically distinct from AD. All clinicians should be aware of the typical triad of clinical features (fluctuating cognitive impairment, visual hallucinations and parkinsonism) which characterise the disorder and either avoid antipsychotics or prescribe them with extreme caution in such patients. Further research is likely to result in advances in diagnostic methods and therapeutics in the near future.