Use of atypical antipsychotic drugs in old age psychiatry

Antipsychotic drugs are among the most widely prescribed psychotropic medications for elderly people, particularly for the 5–8% of patients who are in institutions. The antipsychotics are indicated for treating psychotic disorders, including schizophrenia, delusional disorder, psychotic symptoms in mood disorders and for a number of organic psychoses. Behavioural and psychological symptoms in dementia (BPSD), such as agitation, aggression and psychosis, occur at some point in over 80% of patients with dementia (Ballard et al, 1995). These symptoms are distressing to patients and troublesome to carers, and often precipitate admission to residential facilities. Currently, antipsychotic drugs remain the only established pharmacological treatment for BPSD. Clearly, elderly patients, particularly those with dementia, have much to gain from the development of antipsychotic drugs with proven efficacy and better tolerability. In younger patients with schizophrenia, the new atypical antipsychotic drugs, which have these properties, have revolutionised treatment. Studies on these patients have shown that new atypicals have an equal or greater efficacy than conventional antipsychotics, provide a greater reduction in negative symptoms and cause significantly lower rates of extrapyramidal side-effects (EPS) and tardive dyskinesia (Beasley et al, 1997; Wahlbeck et al, 1999). But is there any evidence that atypical antipsychotic drugs are effective in treating psychosis related to psychiatric disorders in the elderly? And if there is, what are their distinct advantages over conventional antipsychotic drugs? Is it possible to devise rational guidelines for the use of atypicals in late-life mental disorders, from the growing body of literature? We start with an overview of indications for the use of antipsychotic drugs and the features that make these drugs atypical. We then address special considerations in the use of antipsychotics in the elderly, including pharmacokinetic and pharmacodynamic changes in ageing, medical comorbidity, drug–drug interactions and tolerability. Finally, each atypical antipsychotic is discussed with regard to its specific pharmacological properties, its efficacy and its side-effect profile. We conclude with some general recommendations.