Dementia with Lewy bodies: clinical features and treatment.

Dementia with Lewy bodies (DLB) accounts for 15 to 20% of late-onset dementias. The overlap of cognitive symptoms, neuropsychiatric features, parkinsonism and severe sensitivity to antipsychotic drugs raise a number of key management issues. The neurochemical profile of DLB provides a good theoretical rationale for the potential value of cholinesterase inhibitor therapy, which is supported by clinical evidence from a number of case series and one placebo-controlled double-blind trial. It appears that cholinesterase inhibitor treatment is well tolerated and improves fluctuating confusion, cognition and psychotic symptoms; however, the evidence can still only be considered preliminary and a further double-blind study is imperative. Given the high prevalence of severe sensitivity to antipsychotic drugs in patients with DLB, their role in the treatment of psychiatric symptoms and behavioural problems is uncertain, although a small case report literature indicates that some patients may benefit. On the current balance of evidence, prescription of antipsychotic agents to patients with DLB is not recommended, although further studies focussing on patients with severe and intractable neuropsychiatric symptoms are required. Provisional case series indicate a high degree of motor response to levodopa therapy, although controlled trials are a priority to carefully evaluate the benefits in the context of possible adverse effects, such as the exacerbation of psychosis.