Research and innovation

Dementia patients at risk from antipsychotic drugs

Use of antipsychotic drugs in people with dementia is associated with higher risks of a range of serious health outcomes compared with non-use, according to a study.

White pills and a jar in human hand on a wooden table

Higher rates of stroke, blood clots, heart attack, heart failure, broken bones, pneumonia, and acute kidney injury were seen in dementia patients given the drugs, compared with those who were not, data gathered over two decades suggests.

The risks are highest soon after starting the drugs, underscoring the need for increased caution in the early stages of treatment, the study team says.

Existing concerns

People with dementia commonly experience behavioural and psychological symptoms, such as depression, anxiety, agitation or difficulty with sleeping. Antipsychotic drugs are commonly used to help manage these symptoms but there are a number of safety concerns about them.

Existing regulatory warnings on prescribing antipsychotics for these symptoms were developed based on evidence of increased risks for stroke and death, but evidence of other adverse outcomes was less conclusive amongst people with dementia.

Collaborative study

Researchers from the Universities of Edinburgh, Manchester, Nottingham and Dundee set out to investigate the risks of adverse outcomes, such as strokes, blood clots and pneumonia, potentially associated with antipsychotic use in people with dementia.

Anonymised data on illnesses and deaths in England identified more than 170,000 people diagnosed with dementia between 1998 and 2018, who had not been prescribed an antipsychotic in the year before their diagnosis.

Of these, more than 35,000 were prescribed an antipsychotic on or after the date of their dementia diagnosis

Use of antipsychotic drugs was associated with increased risks for almost all adverse health outcomes.

For almost all of these health effects, risks were highest during the first week of antipsychotic treatment, particularly for pneumonia.

The researchers estimate that over the first six months of treatment, antipsychotic use might be associated with one additional case of pneumonia for every nine patients treated, and one additional heart attack for every 167 patients treated.

Although care was taken to adjust for other possible causes, experts say that because their study was based on data gathered from health records, it is not possible to rule out other causes of the observed harms.  

The study was funded by the National Institute for Health and Care Research and published in The BMJ.

Antipsychotic drugs are commonly used to treat distressing behaviour in people with dementia. This research identifies several important harms of this prescribing. We need to find better ways of managing these symptoms which are less risky than these drugs.

Professor Bruce GuthrieAdvanced Care Research Centre, The University of Edinburgh

In recent years, it has become clear that more people with dementia are being prescribed antipsychotic drugs, despite existing regulatory safety warnings. It is important that any potential benefits of antipsychotic treatment are weighed carefully against the risk of serious harm, and treatment plans need to be regularly reviewed in all health and care settings.

Professor Darren AshcroftThe University of Manchester

Related links

Read the full paper in The BMJ

Advanced Care Research Centre

Image credit: mizar_21984 via Getty Images